Mark V 90 watt tube rolling

[bandit2013]

Not all Mesa amps follow the same rules when it comes to the cascade. Most do where V1 is the very first stage. Amps that do not follow the topography: Stiletto, Royal Atlantic, Triple Crown, and probably some others. However the Mark V90 has the basic cascade but with some differences to its predecessors.

Once you break it down into the three channels, it may help understand or confuse the concept.
I will note each triode and if any functions reside or follow it will be mentioned.

Signal chain for CH1:

• FX loop Active: V1A -> tone stack and gain -> V1B -> (reverb signal out/in) -> V3A -> V3B (channel master) -> GEQ circuits -> (fx send) => (fx return) V6B (output volume /solo boost) -> V7 (phase inverter) [ch1 presence]--->> power section.
• FX loop full bypass: V1A -> tone stack and gain -> V1B -> (reverb signal out/in) -> V3A -> V3B (channel master) -> GEQ circuits -> V7 (phase inverter) [ch1 presence]--->> power section.

Notes: V1A plate resistor is 100k, Gain circuit has a few relays to alter gain circuit from clean, fat, tweed. Reverb network has different changes to it based on clean,fat, tweed. V3B has a change in grid stopper value for bold. V3B voltage divider following stage is added (tweed mode only).

Signal chain for CH2:

• FX loop Active: V1A -> gain -> V2A (tone stack) -> V1B -> (reverb signal out/in) -> V3A (channel master) -> GEQ circuits -> (fx send) => (fx return) V6B (output volume /solo boost) -> V7 (phase inverter) [ch2 presence]--->> power section.
• FX loop full bypass: V1A -> gain -> V2A (tone stack) -> V1B -> (reverb signal out/in) -> V3A (channel master) -> GEQ circuits -> V7 (phase inverter) [ch2 presence]--->> power section.

Notes, V1A plate resistor is 100k for crunch/Mark 1), changes to 147k for edge. Edge mode introduces a brightness bypass cap on gain circuit. Mark 1 mode revoices the V2A with large cathode bypass cap(15uF). The tone stack has many manipulations with relays to alter its characteristics for the edge, crunch, mark1 voice. V1B drops the 15uF cathode bypass capacitor for edge mode. V3A has some alterations on the channel master based on edge, crunch, mark 1, There are some JFETS that can pull in a combination of several cathode bypass caps.


Signal chain for CH3:

• FX loop Active: V1A -> tone stack -> V1B -> (gain) -V5A ->V4B-> V3A -> (reverb signal out/in) -> V6A (channel master) -> GEQ circuits -> (fx send) => (fx return) V6B (output volume /solo boost) -> V7 (phase inverter) [ch3 presence]--->> power section.
• FX loop full bypass: V1A -> tone stack -> V1B -> (gain) -V5A ->V4B-> V3A -> (reverb signal out/in) -> V6A (channel master) -> GEQ circuits -> V7 (phase inverter) [ch3 presence]--->> power section.

Notes: V1A plate resistor is 150k, V4B bright switch disconnects cathode bypass cap. V6A, several changes to voice gain characteristics per voicing. Mark IV bypasses grid resistor. IIC+ changes cathode bypass capacitance from 15uF to 4.4uF, Extreme adds in additional capacitance to alter negative feedback of the presence function.

It has been a while since I fired up my Mark V90. I wanted to experiment with different power tubes to hear what sounds best. SED=C= 6L6GC were the pinnacle of greatness but worked best with the JAN/Philips 12AT7 in V4 as the =C= has no reserve on the top end. The STR440 were similar in some respects but more flat sounding. =C= were the only tubes that gave me that 3D sound. Anyhow, since they are very hard to find, I wanted to leave them as reserve or back up tubes. Since I converted my V90 from a head to combo, I needed to swap out the speaker from what I had in there. OTR G12F that has some high frequency roll off. I chose to use the EVM12L Classic instead as I had one of those installed in a widebody open back 112 extension cab.

Installed the EVM12L Classic but left chassis out so I can tune the preamp first.

I loaded the preamp with the following:

V1 (stock Mesa 12AX7), V2 (stock Mesa 12AX7) V3 (Mullard CV4004) V4 (stock Mesa 12AX7) V5 (Mullard CV4004), V6 (Mullard CV4004) and V7 (Mullard 12AX7A long plate reissue). I used to have a Sovtek LPS but it is the same tube as the Mullard Long plate reissue but of lesser quality. I did try the JAN/Phillisp 12AT7 and it made no difference at all. That was new. Even tried an RFT 12AT7, a bit darker tone but again, not much of a difference. Tung Sol 12AT7 I pulled from my Bass TT800 was bright as hell. I did not want to open up that cabinet to get the JAN/Phillips 12AT7 out. The other JAN 12AT7 I stuffed into the TC amps. The Mullard CV4004 do have a nice gain characteristic over the broad frequency range. I did have all Mesa 12AX7A tubes in the amp before. Odd that the 12AT7 did not provide the saturation effect like it did before. It may have been a bad tube. Since it made no difference I just left the preamp loaded as I listed it. Started with the STR440, then tried the STR443, STR448 and finally to what I felt sounded the best STR441.

STR448, not bad, just blah sounding. As if it was swamped with too much low end. Those tubes are much better in the Badlander or the JP2C.

What sounded the best, but not as good as the SED=C=6L6GC tubes were the STR441. Before those, I could not stand the Mark V90 through any V30 loaded cab. STR441 actually made the vert 212 sound good for a change. I still prefer the EV speaker with this amp. Edge actually sounded more usable. Ran through all voices on all channels. Overall, the STR441 complemented each channel very well.

When I was finally satisfied with the tubes and such, finished it off with chassis install and ran through the amp voices again, all power modes, etc. Before changing to the different preamp tubes and power tubes. The only time I preferred edge was with a 7 string guitar. Other than that it was useless. Now it sounds better, almost similar to the low gain voice on the Triple Crown only thinner in tone. However, the STR441 did not favor the 7 string as much as the STR440 or =C= 6L6GC tubes. I may have to try a mix of different 6L6GC tubes in the class A positions. Not sure what effect the 10W power mode will have on that. For now I finally felt like I can run with this as I did not get the typical ear fatigue and give up as the midrange content would drill into my head. Now that character is gone. STR441 for the win, except for use with the 7string. Will look into that again this weekend. I guess I will not be dragging this amp out to the curbside just yet. I still favor my other amps though, Badlander, JP3C, Royal Atlantic are on my top lists. MWDR, Roadster, Triple Crown sort of sit in the middle and the Mark V was last. It actually sounds great for a change.

 

[user 83127]

Wow...thai is some work and goes a little way to explaining the unexplainable way this amp acts...it is an ENGINEERING ABORTIUON...not sleek or refined...just a jumbled ******* mess of compromise and fallacy...THEY SHOULD HA?E STUCK WITH THE 2C+ design!!!) (I have looke dat Mesa amps for years and the one thing I have always found...they are REALLY poorly engineered...the Mark 2c+ was an ACCIDENT...they had a basically cvlean amp and TACKED A HIGHJ GAIN CHANNEL ONTO IT...not elegant at all ...more a quick fix...and a happy ACCIDENT...the rest is just Mr. Mesa guy ( I truly am blankling on his name righ tnow) TRYING to FIX the engineering DISASTER he made with the first amp and make it ELEGANT...he did not...he ****** it ROYALLY...I would make a bet that the Mark 7 does not have that convoluted **** (YET it is STILL and amp of compromise...go BACK TO THE HAPPY ACCIDENT!!!!) My guess is the Mark 6 didnt happen BECAUSE Gibson brought A REAL ENGINEER and pointed this out to him, so they made it a DUMBED down yet probably correctly engineered amp. I miss the older amp and will probably spend my life looking for an affordable one!

 

[bandit2013]

I admire Mesa products. Perhaps the Mark V was not to my expectations like the previous versions I used to have. It is different. Perhaps it would be a better amp if they did not attempt to make it into a novelty product. Not sure how close the Mark I voice is to the real deal. Why even choose that as a descriptive label. No one complains about crunch sounding like a crunch (so what model is that supposed to be? ). It is just a label on a panel that describes what it sounds like I suppose. Obviously IIC+ and IV do no justice the actual amps as identified by using a descriptive label do define the voice characteristics. Sounds nothing like a IIC+ or IV. It is just an amp, nothing more.

I would be surprised if the Mark VII had a label on it that said Mark V. So what would that indicate?
Considering a IIC+ is somewhat like a Mark III, well, what is the assumed setup on the amp that the V emulates. Well obviously the circuitry of the Mark V is nothing like its predecessors. Interesting in design but not my favorite amp.

What is epic to me, though others will ***** and complain and say: may as well buy a Marshall. Go ahead. I like my Badlanders, and Royal Atlantic RA100s. And I do have a Marshall, it is ok.

You either like it or you don't. Not all amps are for everyone. Sometimes you like it, and sometimes you don't.

Sure, there are those who criticized the JP2C. It sounds nothing like a IIC+. Well, which IIC+ are we talking about? HRG, DRG, what? I will say it does not sound like them only for one reason. It is not shipped out with the proper power tubes. Then again there are some IIC+ models out there that will only work with specific power tubes due to the power transformer and associated plate voltages. Sure at that time, those tubes were still in production. Now, they are not. I do not mind that my JP2C is different than that of the bygone era. I can make use of it with many power tubes that would just get fried in an original IIC+. However, If I had to base my judgement on the amp with the power tubes it was so equipped with, I would say it gets close. At least the STR440 power tubes do the job. When that company had to close shop and no more STR440 out there, that tends to become a challenge to find a power tube that works well. The STR443 is not the best for the JP2C. I tried them and lost interest in the amp . Then came along the TAD red-base 6L6GCM-STR tube aka STR448. Well that was a surprise, they sound f-ing great in the JP2C. Those same tubes sound epic in the Badlander. I tried them in every mesa amp I have. STR448 is good for JP2C and Badlander but they suck in the other amps. Same would apply to the STR441, really good in the Mark V but sound mediocre in the other amps. At this point, I can clarify that the JP2C does sound as close to the IIC+ amps I have heard in videos or recordings. You just need the right tubes. Sylvania STR415. I bought them from Mesa and they arrived a few days after I got the STR448. I would say the 415 and 448 sounds similar but yet different in the JP2C. As for the STR415, I will not use them in any other amp as they found a home in the JP2C. The STR448 are going to be used in the Badlander, waiting on the second set I ordered to install into the other Badlander.

I am one to admit that the Mark V90 is not for me, at least the one I wound up with. I have played a few others that were way better back in 2012. That was around the time Guitar Center stopped carrying the Mesa product. Now it is back due to Gibson. I may have been on a tone quest for the past 10 years. I doubt that will ever end. Will I stick with Mesa or go elsewhere? Depends on what is next. For now, I can pick and choose what I want. I do not have to go very far to get the sound I am after, just a few steps and there it is, packed up in the hallway waiting for some attention. This is just some of it, I have too many to line up in the same room as it will not fit. (Badlanders, MWDR, Cali-tweed are not shown.) I should get one of the Royals out as it has been at least a month since I played through them last.

So if Mesa is all that bad, what is your preference. I gave up on the forums for a while, mostly the Mark V forums. I had no praise for the amp. There was no point in making that clear. It is not all that bad, it just does not live up to my expectations. I still have it. Not ready to sell it just yet.

 

[user 83127]

I used to admire them...when I was young in the 90's...when Petrucci was the man and when i thought that you buy a Mesa product..you know what sound you are getting...The Mark 1 had MANY sounds...the worst was chosen to be represented on the Mark V...crunch is what JP says crunch is...that is what that means. And when I say iI used to admire them...it was because they had unparallelled customer service and if you had an issue...and issue...they would fix it (even tone)...THEY HAVE NOT BEEN THAT COMPANY SINCE THE EARLY 2000's. That is fact. And when you say that the earlier Mark V's had THE sound you would expect...YOU ARE DEAD RIGHT...they made a change..are denying it and anyone the right to revert to the original Mark V circuit (because they are just TOO fuckig lazy to even bother to try and work on their OWN OVER COMPLICATED DESIGN...what does that tell you...they they are a company worthy of admiration... (I WOPULD TRAHTER ADMIRE SOLDAN>>>he hasnt given up his Design philosophy or desire to put out a great product...or at least he never di when he owned the company...I dont know if he sold it by now...so many do) and you have something against Marshall..they are THE SAME as Boogie basically...just further along and with a different sound...I have a TSL that I modded and it
KIOC}KS ***...but I had to mod it because it sucked...at least there are mods and people that will talk about it...MEsa (this sire had several that tried to mod it (including you if I remember) .and Mesa blanked those pages completely...so dont tell me what a great company they are...sorry...not you ...not mad at you...just venting frustration and you gave me an in with your surprising fan boy rant...I though you are smarter than that.
And finally..for the record...I ''LOVE the boogie sound...LOVED the Mark sound...Mesa proved that they KNEW what the mark sound was because when they issued the MArk V it truly had the sound of Boogie....they changed it...they ****** it up...they REFUSE to admit they did it....call us crazy for even suggesting it and REFUSE to work on the amp they made under any circumstances except catastrophic failure and even then they will encourage you to take it elsewhere,...they are not longer a company that I even want to do business with except maybe for used parts (I will never buy another new or newish Boogie product AGAIN..PERIOD.) and you talk like a boogie engineer..is it werent for the fact i dont think anyone could keep your personna up for a s long as you have without being outed I would swear you were (you KNOW THEM and you DEFEND them like an employee)...maybe they should court you to work on them...new enthusiastic blood to show the Gibson guys how to do it!!!!! (that is a compliment)...I have an odd way of expressing myself but that long winded rant WAS a compliment to YOU.

 

[bandit2013]

I appreciate the complement. However, I am not a Mesa Boogie or Gibson employee. Would be nice to be on their payroll as a design engineer. I never worked for the company or any of its competitors. I can appreciate your comments and despair as I have been there myself. Yes, I can agree that the customer service is not what it used to be. If you call in, you have to leave a message and you may get a return but the call comes out of Nashville, not Petaluma. Emails do get through to the respective people at Mesa. That is how I secured my purchase of the STR415 tubes. The customer service tech who called me back out of Nashville tried his best, but at the Gibson perspective, if the parts are not listed in catalog or website, they do not exist. Did not matter if I shared the email communications I had with the Mesa person. I was able to work it out and got the power tubes in question. They still have these tubes but at limited quantities. Not inexpensive either but reasonable compared to the NOS market place for similar tubes.

Every amp, guitar, effects and such, I paid for out of my pocket. I worked hard and struggled at times to get it. I have no affiliation with any musical group, nor do I get any free samples. I am a nobody in the musical industry and I would rather it be left that way. I do not do any side jobs for others and have refused becoming a moderator of these forums or any other forums. I do not work for free but the time I spend here I do it out of my enjoyment for the hobby. Yes, music is my hobby and not a career path. I would rave about Tama just as much as the StarClassic is one of my favorite drum sets. God does that thing sound so good. I am not a guitarist, drummer or bassist. I just enjoy playing while I still can. If something gets discovered by chance, I will make note of it.

My name is Eric Hokanson. I have spent my entire career as an electrical engineer in the HVAC industry. Started out fresh from college and worked for a small company in PA that is now closed, designed many products for that industry for almost 2 decades before getting laid off in 2009.

Landed a job in North Carolina called Field Controls. It is a bit different than what I used to do but far more complex in some respects, so it has been a rewarding change as I am always challenged. Almost like getting diamonds out of an orange. I would have said getting blood from a stone was difficult, but of you throw it hard enough and hit someone in the head, you will get blood very easily. I am not in the practice of throwing rocks or stone. I am just making a point on challenges that get keep me thinking and how to be innovative to get the job done. With that being said, I will work hard at understanding what I do not know and will do the research to improve my knowledge of such. My personal skills may be lacking. Verbally, I probably speak my mind and may use plenty of colorful four letter words. That is unless I am responding to a customer call for customer service which is not often. If the techs cannot handle the issue or concerns, they pull me in to resolve it. Our other engineers will also take charge and go to great lengths to support our customers. I always found it helpful to get a customers perspective as it sometimes gives you a heads up some changes are needed.

https://www.fieldcontrols.com/
I am the only electrical engineer they have. I also do firmware development for the products I create as well as the mechanical design for projects I am assigned to work on. At the time I started at that facility, I only had a Mark III combo (blue stripe) and a Mark IVb combo. Both have been sold off at least 10 year ago.

I started out playing with a Fender Deluxe Reverb and moved on to a Marshall MOSFET100 (not worth buying). I could not afford a Marshall tube amp at that time. Never heard of Mesa boogie at that time. But a year after getting the Marshall, that is what replaced it. Mark III combo. This was the same time I formed a band back in 1989. I needed an amp that would keep up with bass and a drums.

Those amps served me well and have always been a desired amp for me. Due to some life changing event, loss of my wife in 2012, I made a promise to her I would take up playing the guitar again as she heard me playing for the first time when I was prepping the Mark III for sale to a friend. I wanted to make sure it still worked as it was 24 years old. I had quit playing guitar after ripping tendons in my left arm while shoveling snow in PA following one of the blizzards. Left arm was useless for nearly 8 years. Since there was this void in my life, I filled it with music. Since I sold the Mark III, I wanted to get a Roadster. When I tried it out, could not figure it out, tried a Mark V90 and it seemed familiar to dial in. I should have taken the one I tried but opted for the clean one in the corner. Well that amp was a disaster. Red plate every power tube, Chassis would get so hot it would burn you. I could have sent it in for service but no. I decided to look it over myself. Found a resource full of schematics, mostly old version and the Mark V was not complete as it did not have the content for the switch gear. Dated as 2009 so it was the first release of the amp. It was changed in 2010 (modified tone stack) as I was informed by others in the forums of this change. However, the 2009 schematics were of use and much of what is on the preamp is accurate. So I spent some time digging into tube triode circuits, power tube circuit design and basic theory. The Mark V90 was one of the worse Mesa amps I ever bought. When it was not red plating power tubes, all I could get from the third channel was ice pick tones. Edge was garbage, tweed was just as bad and the entire clean channel has a low frequency hum I cannot eliminate. Yep, you guessed it, I started making hard mods to the Mark V90 in hopes to fix the ***** tones, and shrillness. Most of this started during the "saturation mod" thread.

I never said I hated Marshall Amps. I have one and love it. I had thought about getting another one. Comparing construction of that to the Royal Atlantic, the RA is of better quality. Sounds amazing. I believe the closest amp to the Marshall Silver Jubilee 2555x is the TC-100. Not sure why some believe the hype on the TC as having the most gain. It does not or at least not in a preamp triode gain stage perspective. Considering the op-amps used in the hi/lo gain stages following the tone stack I can see that having more gain on paper. That is one reason why you cannot tune the amp with different preamp tubes, it will always sound the same as it is over compensated with active filtering. The RA is not in terms of the hi/lo preamp section. That one can be tuned. I wish I had the schematics for the RA as it will help me better understand it.

I even have an EVH 5150 as I was on an EL34 kick decided to get the EL34 100W model.

Perhaps my preference is for Mesa as it was a more affordable boutique amp company. Not much anymore as prices have gone up. I did consider a Dynamo amp at one time: Home | Dynamo Amplification

I had thought they have gone out of business, but they are still around. I see they have some new bass gear. Will have to look into that.

As for me, I dig into the amp and not just its sound characteristics, I want to better understand what is going on inside. Can I mod it or not?

Why I stopped contributing some time ago, it was my stance on some amps. I was negative on the Triple Crown, Negative on the Mark V. I took a step back and realized this negativity was not appreciated. I also had to consider others opinions and I know how much these amps cost even used. That is a lot of money especially when living on a budget. I am doing ok but have been there struggling to make ends meet (for the first 40 years of my life). I try to respect other's opinions. Sometimes just staying out of the forums was the way to go. I am back with a different frame of mind.

 

[shawnohio]

Not all Mesa amps follow the same rules when it comes to the cascade. Most do where V1 is the very first stage. Amps that do not follow the topography: Stiletto, Royal Atlantic, Triple Crown, and probably some others. However the Mark V90 has the basic cascade but with some differences to its predecessors.

Once you break it down into the three channels, it may help understand or confuse the concept.
I will note each triode and if any functions reside or follow it will be mentioned.

Signal chain for CH1:

• FX loop Active: V1A -> tone stack and gain -> V1B -> (reverb signal out/in) -> V3A -> V3B (channel master) -> GEQ circuits -> (fx send) => (fx return) V6B (output volume /solo boost) -> V7 (phase inverter) [ch1 presence]--->> power section.
• FX loop full bypass: V1A -> tone stack and gain -> V1B -> (reverb signal out/in) -> V3A -> V3B (channel master) -> GEQ circuits -> V7 (phase inverter) [ch1 presence]--->> power section.

Notes: V1A plate resistor is 100k, Gain circuit has a few relays to alter gain circuit from clean, fat, tweed. Reverb network has different changes to it based on clean,fat, tweed. V3B has a change in grid stopper value for bold. V3B voltage divider following stage is added (tweed mode only).

Signal chain for CH2:

• FX loop Active: V1A -> gain -> V2A (tone stack) -> V1B -> (reverb signal out/in) -> V3A (channel master) -> GEQ circuits -> (fx send) => (fx return) V6B (output volume /solo boost) -> V7 (phase inverter) [ch2 presence]--->> power section.
• FX loop full bypass: V1A -> gain -> V2A (tone stack) -> V1B -> (reverb signal out/in) -> V3A (channel master) -> GEQ circuits -> V7 (phase inverter) [ch2 presence]--->> power section.

Notes, V1A plate resistor is 100k for crunch/Mark 1), changes to 147k for edge. Edge mode introduces a brightness bypass cap on gain circuit. Mark 1 mode revoices the V2A with large cathode bypass cap(15uF). The tone stack has many manipulations with relays to alter its characteristics for the edge, crunch, mark1 voice. V1B drops the 15uF cathode bypass capacitor for edge mode. V3A has some alterations on the channel master based on edge, crunch, mark 1, There are some JFETS that can pull in a combination of several cathode bypass caps.


Signal chain for CH3:

• FX loop Active: V1A -> tone stack -> V1B -> (gain) -V5A ->V4B-> V3A -> (reverb signal out/in) -> V6A (channel master) -> GEQ circuits -> (fx send) => (fx return) V6B (output volume /solo boost) -> V7 (phase inverter) [ch3 presence]--->> power section.
• FX loop full bypass: V1A -> tone stack -> V1B -> (gain) -V5A ->V4B-> V3A -> (reverb signal out/in) -> V6A (channel master) -> GEQ circuits -> V7 (phase inverter) [ch3 presence]--->> power section.

Notes: V1A plate resistor is 150k, V4B bright switch disconnects cathode bypass cap. V6A, several changes to voice gain characteristics per voicing. Mark IV bypasses grid resistor. IIC+ changes cathode bypass capacitance from 15uF to 4.4uF, Extreme adds in additional capacitance to alter negative feedback of the presence function.

It has been a while since I fired up my Mark V90. I wanted to experiment with different power tubes to hear what sounds best. SED=C= 6L6GC were the pinnacle of greatness but worked best with the JAN/Philips 12AT7 in V4 as the =C= has no reserve on the top end. The STR440 were similar in some respects but more flat sounding. =C= were the only tubes that gave me that 3D sound. Anyhow, since they are very hard to find, I wanted to leave them as reserve or back up tubes. Since I converted my V90 from a head to combo, I needed to swap out the speaker from what I had in there. OTR G12F that has some high frequency roll off. I chose to use the EVM12L Classic instead as I had one of those installed in a widebody open back 112 extension cab.

View attachment 1685

Installed the EVM12L Classic but left chassis out so I can tune the preamp first.

View attachment 1686

View attachment 1687

I loaded the preamp with the following:

V1 (stock Mesa 12AX7), V2 (stock Mesa 12AX7) V3 (Mullard CV4004) V4 (stock Mesa 12AX7) V5 (Mullard CV4004), V6 (Mullard CV4004) and V7 (Mullard 12AX7A long plate reissue). I used to have a Sovtek LPS but it is the same tube as the Mullard Long plate reissue but of lesser quality. I did try the JAN/Phillisp 12AT7 and it made no difference at all. That was new. Even tried an RFT 12AT7, a bit darker tone but again, not much of a difference. Tung Sol 12AT7 I pulled from my Bass TT800 was bright as hell. I did not want to open up that cabinet to get the JAN/Phillips 12AT7 out. The other JAN 12AT7 I stuffed into the TC amps. The Mullard CV4004 do have a nice gain characteristic over the broad frequency range. I did have all Mesa 12AX7A tubes in the amp before. Odd that the 12AT7 did not provide the saturation effect like it did before. It may have been a bad tube. Since it made no difference I just left the preamp loaded as I listed it. Started with the STR440, then tried the STR443, STR448 and finally to what I felt sounded the best STR441.

STR448, not bad, just blah sounding. As if it was swamped with too much low end. Those tubes are much better in the Badlander or the JP2C.

View attachment 1688

What sounded the best, but not as good as the SED=C=6L6GC tubes were the STR441. Before those, I could not stand the Mark V90 through any V30 loaded cab. STR441 actually made the vert 212 sound good for a change. I still prefer the EV speaker with this amp. Edge actually sounded more usable. Ran through all voices on all channels. Overall, the STR441 complemented each channel very well.

View attachment 1689

When I was finally satisfied with the tubes and such, finished it off with chassis install and ran through the amp voices again, all power modes, etc. Before changing to the different preamp tubes and power tubes. The only time I preferred edge was with a 7 string guitar. Other than that it was useless. Now it sounds better, almost similar to the low gain voice on the Triple Crown only thinner in tone. However, the STR441 did not favor the 7 string as much as the STR440 or =C= 6L6GC tubes. I may have to try a mix of different 6L6GC tubes in the class A positions. Not sure what effect the 10W power mode will have on that. For now I finally felt like I can run with this as I did not get the typical ear fatigue and give up as the midrange content would drill into my head. Now that character is gone. STR441 for the win, except for use with the 7string. Will look into that again this weekend. I guess I will not be dragging this amp out to the curbside just yet. I still favor my other amps though, Badlander, JP3C, Royal Atlantic are on my top lists. MWDR, Roadster, Triple Crown sort of sit in the middle and the Mark V was last. It actually sounds great for a change.

View attachment 1690

Great setup. I have an express 5/50 original, with an extra evm12L it turns into a whole nother thing. I lean toward classic rock and I get a wide range of sounds out of it. Most of the preamp tubes are mesa, there seems to be no intuitive way to tube it though. You have to experiment. I got a matched pair of vintage 6l6gc tong-sol before the fiascos they sound great! Look for them on eBay, they pop up at a good price

 

[bandit2013]

Great setup. I have an express 5/50 original, with an extra evm12L it turns into a whole nother thing. I lean toward classic rock and I get a wide range of sounds out of it. Most of the preamp tubes are mesa, there seems to be no intuitive way to tube it though. You have to experiment. I got a matched pair of vintage 6l6gc tong-sol before the fiascos they sound great! Look for them on eBay, they pop up at a good price

Sometimes the EV speaker can sound sterile. Depends on the amp in most respects. It will sound very boxy with the Triple Crown or a British voiced amp. Not sure if I like the Black Label or the Classic better. They are not exactly identical but very close. I did run my Roadster with a rebuilt OS Recto 412. Did not care much for the 70W V30s that were in it. I still have them in boxes the EV speakers came in since I barely used that 412 cab when I bought it back in 1999/2000. All of that soft weather stripping was necessary as the grill would vibrate and make some serious noise. I ended up having to screw the grill down from the front as the wood in the frame got stripped out from removal too many times. Now that I got the JP2C up and sounding great, I should dig the cab out of storage and become overwhelmed. To my surprise, it actually worked good with the Roadster. As of late something odd is up with that amp, Makes me wonder if I got a hanging relay on the feeback circuit as it is now super bright. I can still alter the tone on the presence in control when using modern, it did not matter what channel I used, it is just now too bright. I will take a closer look at it some other time.

 

[user 83127]

Bandit..you have to know that I have been following you in an I look for your posts because they have the most sense and tell me something since I bought mine first Mark style amp and hit the forum and saw you posting. That being said (not in a weird way..no some freak here) my name is Timothy (read Tim) Martin and I live in upstate New York. I have grown up here in various places including my ancestral home of Willsboro New York and Plattsburgh (where i spent my formative years)...that is until I moved to North Carolina to be near other family and lived for 16 years before moving back here to beautiful Brownville New York (next to shiny happy Lake Ontario...where boating is about all there is to do...lmao)(Lake Champlain was prettier in my youth and there was Champ!!!)...I begged people to teach me to play guitar as a youth (several aunts and uncles and all said the same thing..."its too hard...you wont stick with it)...so when a chance to learn and instrument came up in the fifth grade I CHOSE THE ONLY ONE COOL ENOUGH>>>DRUMS!!! I was pretty good or so I thought...I learned from a trumpet teacher so what did i know. He taught me well enough that at 12 I got a standing ovation for a rendition of Rock Around The Clock from the senior class and parents performances. I was a hot head and quit there, then when I transferred to another school where they wouldnt teach you unless you had your own set (but they had a master Jazz teacher...I wanted to learn from him so bad...No one in my life would buy a set for me so I gave up the dream until I got to North Carolina...MY mother bought me one of my all time personal favorite sets for sound (Tama are amazing!!!)... a Ludwig Chrome 7 piece single kick with avedis zildian all around.)..I attempted to teach myself well enough to apply at the North Carolina School of the arts and found out WHAT A REAL DRUMMER SOUNDED LIKE (I auditioned opposite someone that learned from one of BB kings drimmers...AMAZING..the whole school stopped classes to hear him warm up (he started warming up and the WHOLE SHOOL CAME IN TO SEE..it was incredible...****oy and Peart level...not Buddy Rich...but he was 19)...so I got seriously demoralized and sold my drums and went into construction work where I lived most of my life (actually a short stint in the Navy where I learned basic electronics)..construction and BLOWN BACK (actually working for the government on a temporary basis one winter)...NO MORE DRUMMING...I picked up a guitar out of boredom (a 12 string Madiera by Guild) and have been playing since,,,Totally self taught...I now have my Les Paul (Gibson Studio 1994 ebony fret board) My Jackson (MIJ 2004 DKMG emg 81/85 changed to Dimarzio SD neck and Duncan Full shred bridge..custom wiring for push/pull configuration and 3 way dpdt giving coil tap...coil selection...phase reversal and kill switch functions...al with 50;s wioring because I LIKE IT!!!)..I actually invented this mix..or came up with it myself..maybe invent is not the word...I got my first tube amp JCM900 6l6 (5100...I LOVE EM<...was killing my ears..wayy too loud..sold it to buy a Mesa Studio Pre that was busted to hell...I fixed that and sold it to buy my Mark V...bought a TSL on a deal (the guy thought it had the bias drift..it didnt..it had other issues..but he TOTALLY screwed up the repair (left paper tags laying on the board and they were actually shorting connections and you would get things like a pot would work...but BACKWARDS..so i fixed that and all the cold solder joints and had a working but ****** sounding TSL...then the transformers burned up (the power...the 12 volt rail went up in smoke)..so I fixed that and added a new PT and choke to the circuit...obviously learning all this time about the amp...then embarked on a modification phase where I tried literally every mod out there/..Europa mod et all hated all of them but had done some changes incrementally so was REALLY beginning to understand what made the amp tick and realized they had oversized one resistor in the "Fat " circuit...dropped it appropriately...took out those little switches that engage that terrible bright mode on the red channel and viola...I have one screaming unique Marshall TSL(in North Carolina the winters afford you time off so there were temp jobs where I actually soldered stained glass and circuit boards up for months at a atime...so I get my soldering skill naturally...i am a MAD solderer//I can rework ANY circuit board (rework WAS my job)...
so...56..self taught in every way with electronic and musicianship...Wish Mesa was the company they used to be (and I was speaking of the company at the end...NOT GIBSON....I actually was pretty pissed off over an interaction i had with them in 2014 buying parts and then in 2016 attempting to get this Mark V decent,,they were no help...I spent 200 sending it across country,,,they soaked it for 24 hours and told me I was out of my mind and they didnt warrant voicing AND they would do NO mods no matter how badly I begged (not the company I heard they were AT ALL)...i so never even gave Gibson/Mesa a look. I now have a Triaxis V2 non phat..the MArk V...the TSL and a 6505 MH...i pump these through Marshall 1960 A and B cabs original speakers (2004 and 1998) with a 31 band stereo EQ and a TC G Force (various pedals and whatnot)..i play a mean guitar...am at present forming a writing partnership with a local musician who has no desire to our either (bars and schmuicks not my thing..but creating very much is) and am VERY long winded....a 146 IQ all knowing fountain of useless knowledge is what they have at times called me!!!LOL...try not to be abrasive while at times not caring with a 4 letter vocab that DEFINATELY get s me in trouble...i dont care if we disagree...i dont care if you just do not know..but t l;east keep an open mind and dont just fly off and call me ignorant..cause the person saying that is USUALLY the one in the wrong AND is usually showing GREAT IGNORANCE...so i get myself in trouble...but thoroughly enjoy good conversation and exchanging ideas...and THIS IS ENJOYABLE...even if people think we are stroking ourselves!!!! Smart people are hard to find and they make good conversation and wWE seem to have one heel of a lot of overlap in experience...I am actually not surprised to find this!! The commonality to get this deep comes from somewhere because most people would say we are just guilty of verbal diarrhea (been told that enough)

 

[Darkstar2]

Hi Bandit — I too have a new JP2C and would lov3 a quad of Mesa 415s. If you don’t mind me asking, what did you have to give for a set of 4?

 

[bandit2013]

Tim, it is all good. I respect your comments. Thanks for sharing the drumming story. I am there now. I am not a drummer but play the drums in what I would call an old-fart group of engineers who think they are musicians. All three of us have played nothing but guitar for god knows how long. 30-40+ years. Everyone was self taught. The guitar player in the group did have an advantage as his mother was a professional musician. Growing up I was forced to learn piano and hated every second of it. That only lasted a short while. Was not allowed to get a guitar, end of story. However, my sister bought one, and guess what, I found where she hid it and taught myself how to play. There was a point in time, one of my friends suggested I seek out taking lessons. I tried such, and the person providing the lessons (supposed to have been an independent musician that said he used to play with Eddie Rabbit). He said on the second or third lesson that he cannot teach me, you are holding the instrument wrong, your fingers are too short and you lack the ability and have no talent whatsoever. F-Y was my response to that but not to his face. What a prick. That never stopped me and I did eventually form a band as the lead guitarist back in 1989. Now we get to this point in time, some 30 years later I got a digital multitrack recorder (modern but old school compared to using a PC). I started experimenting and learning how to play drums and bass at the same time. Perhaps I don't have any talent. I don't care. All that matters is having fun right? So the old-fart group was working out ok but noticed the guitar player would get lost. We would start the song out correctly then he jumps into some unrelated solo and forgets what we were playing in the first place. I stopped recording any of our other jam sessions as they were getting progressively worse. Not sure if it was intentional because I was recording or if it was something else at play. The guitar player recently said sorry if I messed up the recording just a few days ago. What recording? was my response. I stopped doing that a 2 years ago. So here is a what I could salvage from a 4-5 hour jam session as it was the at that point to stop anyway. We started off playing Pink Floyd - Run like hell and got lost in translation. I have to say he was using a Badlander, I let the guitar player dial in the amp. He also added some front end pedals that have seen better days, some control knobs were broken off. Not really sure it was working. Note that the Badlander does not normally sound so sh!tty. The bass player (who is learning the instrument) was also getting bored. I figured I would try to focus my drumming (lack there of) with the bass player. I am not a musician mind you. But I will take any comments good or bad. This is the only recording I have on my soundcloud where I did not play all of the instruments. my apologies up front for calling this music.



This was my seat for the evening: Note the bass rig is not in the picture as this picture was taken before I got the Mesa TT800. I have some old recordings of the Mark Bass JB Player amp I used. So it is a first for getting the Mesa TT800 into digital playback. Note that I have been playing drums for at least 7 years. I suck. I do not practice though. I only man the drums when we jam. I spend the rest of my time playing guitar.

Love it or hate it.

If it was not for the Mark V90, I probably would have not bothered to research the old tech on triode circuits and such. I would have to say I learned a lot in doing so and making mods to the V.

You got me thinking on the V90 Subject. Most of the shrill (assuming you have such issue) is with the preamp and not the power sections. I tried slaving into the Roadster and had the same terrible sound. At least that way I was able to isolate the power section to some extent. Then again, the Mark V does not have a good FX send circuit so some of the brittleness could be attributed to the front end of the GEQ circuit which is all transistor driven. Note this is only due to the shrill character of the amp when any distortion is created (CH1 tweed, CH2 edge, all of CH3). Even when you turn off the GEQ, the signal still passes through the complete GEQ circuit. It never gets pulled out or bypassed completely. Based on the schematic, the GEQ off just places a 1M ohm resistor to ground. When it is turn on, that 1M ohm resistor gets shorted out by a JFET.

There was a post by Mesa rep, Theresa on tube color codes and if you can mix and match them. I was curious what the posters were talking about and then it came to reality on the Mark V. Here is the link

https://boogieforum.com/threads/mesa-color-code-plate-current-values-420-vs-440.86620/#post-534638
Keep in mind since the Mark V90 is a Simul-class amp, it is by design that the Class A circuits run on the hot side. This results in power amp saturation. the Class A/B sockets are just like the MWDR, just coasting and providing some enhancement. You were on the right track with the short tubes in the outer sockets and the longer ones in the inside. If they are mesa branded tubes, look at the color codes. Reds or Yellows will have more overhead and least likely to clip as much. If those are in the center pair, it would help reduce the power amp saturation effect. What you use in the outer pair may not make much of a difference. I will have to take a closer look at the STR441 I tossed in the V and see what the color codes are. I do have some survivors left from the V when it was red plating tubes. I will see if they test ok and try them in the V. I am now curious to hear how that sounds.

I have tried many different Mesa branded power tubes. Mostly marked as Green, or Grays as I was seeking a resolve for the JP2C. I do have some yellows on reserve for the Roadster as that amp sounds like crap with hotter power tubes. At least the Simul-Class amps you can swap in power tubes of different color codes, or variants of the 6L6 so it will not dominate the overall tone. I should have kept the Mark IV as that one was great when blending different power tubes or doing the integrated quad (mix of 6L6 and EL34). They did make changes to the extended Class A portion so the bias voltage will not be where it needs to be to run EL34s. It may work though. I had been tempted to try it. decided not to as the bias circuit in my V is messed up to start with. Probably one reason why I will not try the STR415 tubes in that amp.

 

[bandit2013]

Hi Bandit — I too have a new JP2C and would lov3 a quad of Mesa 415s. If you don’t mind me asking, what did you have to give for a set of 4?

I sent you a PM for the details. In addition to what I left out, I forgot I had to donate my left kidney and a few toes. LOL.

 

[Darkstar2]

Thank you very much for the info and candid reviews / thoughts on Mesa tubes, Bandit! I may need to give those redbase TAD tubes a try in the JP2C as the JJ’s are just OK. I have about 100 hours on those tubes and they are … kind of underwhelming.

I also play Tama’s, Artstar Custom ES’s from the late 90s. Jam on brother!

 

[mace]

Thanks for the info on the Mark V:90 gain stages for each channel.

Still curious how the VII compares to the V for clean, crunch and IIc+ and IV! Seems a lot of the initial hype on the VII has died down now.

 

[bandit2013]

Thank you very much for the info and candid reviews / thoughts on Mesa tubes, Bandit! I may need to give those redbase TAD tubes a try in the JP2C as the JJ’s are just OK. I have about 100 hours on those tubes and they are … kind of underwhelming.

I also play Tama’s, Artstar Custom ES’s from the late 90s. Jam on brother!

This is a bit off topic but...

You are using the STR445 tubes? Never considered those in the JP2C. I did order a quad just to try them out (MWDR). I also see they are using those in the Mark VII.

We are living in some tough times for getting tubes. Sort of reminds me of the early 90s when you could not get any tubes except for Sovtek or GT. No way to get power or preamp tubes unless it was in stock at a local shop or not local shop as I have driven about 200 miles to buy tubes before back in those days. I will not do that anymore.

 

[bandit2013]

Thanks for the info on the Mark V:90 gain stages for each channel.

Still curious how the VII compares to the V for clean, crunch and IIc+ and IV! Seems a lot of the initial hype on the VII has died down now.

You are not the only one on that camp. I never had an opportunity to try one. The only way I can where I live is to order it from Sweetwater. I do not have much faith in the small GC that is 100 miles one way from me on having one. If it does not have Fender brand on it, or made in China on the back of the amp, it is very difficult to find anything of quality where I live. Nobody wants to invest in their inventory for high cost items. They always say we can order it, I will need your money. WTF? Much easier to buy from Sweetwater than else where. Perhaps I will seek out other places if in a pinch.

 

[Darkstar2]

My August 2022 built JP2C (Schumacher transformers) came with STR 443. I will order a set of those STR 448’s (blu) from Mesa in the morning and report back my impressions after I get 10 or so hours of burn-in.

 

[bandit2013]

My August 2022 built JP2C (Schumacher transformers) came with STR 443. I will order a set of those STR 448’s (blu) from Mesa in the morning and report back my impressions after I get 10 or so hours of burn-in.

Blue is on the hot side. I mine were Grays which are the next step in towards the middle.
It should be good after the first thermal cycle (running the amp with the tubes for at least 20 minutes). The STR415 took a bit longer to blossom probably due to age. I only ran the STR448 for a few days though, the STR415s came in and well, you get the idea. Those were tested and marked as green. I believe that is the tube they base their standard on. However, the gray codes on the STR448 may have been to rich for the other amps I tried them in, except for the Badlander. I guess Blue would be ok. I have yet to see that on a 6L6 tube.

 

[Darkstar2]

Do you think I should go with a different color when ordering the STR448's? Grey, like you say, is the next step cooler. I think I can go with another color up or down safely, yes?

 

[bandit2013]

So some may like the V, some may hate it. or some may have a love/hate thing with the Mark V90. I fall into one of those categories (love/hate). I do admire the engineering behind it after digesting the schematics. I thought it was clever how the 10W power mode was handles.

A typical Mark amp historically only has 5 preamp tubes. Topography of the amp design has not changed much from the IIC+ through to the Mark IV. V5 was the phase inverter. V1 was tone stack, V2 was associated with the Send/Return FX loop and V3 and V4 were the lead drive circuits and used for reverb. Along comes the Mar V, things are quite different here. The lead drive circuit is the same but there are some extra gain stages added in before the send level is created (by the GEQ circuit and not derived by voltage divider off of the last gain stage). Generally what is placed in as a form of negative feedback around the lead drive is also different in the V compared to early models. Not sure if any of this contributes to its overall tone, or desired/undesired characteristics.

At least the Mark VII only has 5 preamp tubes, just like the amps before the Mark V. Not sure exactly what is packed in there but would not doubt that the traditional circuit from the IIC+ and IV are present. From what I gathered by those that have the VII, the FX loop appears to be in front of the GEQ so that may indicate it is back to a traditional circuit. I do plan on getting one of the VII but waiting for one that will match my one V212 cab. Creme/Black jute face plate.

 

[user 83127]

Tim, it is all good. I respect your comments. Thanks for sharing the drumming story. I am there now. I am not a drummer but play the drums in what I would call an old-fart group of engineers who think they are musicians. All three of us have played nothing but guitar for god knows how long. 30-40+ years. Everyone was self taught. The guitar player in the group did have an advantage as his mother was a professional musician. Growing up I was forced to learn piano and hated every second of it. That only lasted a short while. Was not allowed to get a guitar, end of story. However, my sister bought one, and guess what, I found where she hid it and taught myself how to play. There was a point in time, one of my friends suggested I seek out taking lessons. I tried such, and the person providing the lessons (supposed to have been an independent musician that said he used to play with Eddie Rabbit). He said on the second or third lesson that he cannot teach me, you are holding the instrument wrong, your fingers are too short and you lack the ability and have no talent whatsoever. F-Y was my response to that but not to his face. What a prick. That never stopped me and I did eventually form a band as the lead guitarist back in 1989. Now we get to this point in time, some 30 years later I got a digital multitrack recorder (modern but old school compared to using a PC). I started experimenting and learning how to play drums and bass at the same time. Perhaps I don't have any talent. I don't care. All that matters is having fun right? So the old-fart group was working out ok but noticed the guitar player would get lost. We would start the song out correctly then he jumps into some unrelated solo and forgets what we were playing in the first place. I stopped recording any of our other jam sessions as they were getting progressively worse. Not sure if it was intentional because I was recording or if it was something else at play. The guitar player recently said sorry if I messed up the recording just a few days ago. What recording? was my response. I stopped doing that a 2 years ago. So here is a what I could salvage from a 4-5 hour jam session as it was the at that point to stop anyway. We started off playing Pink Floyd - Run like hell and got lost in translation. I have to say he was using a Badlander, I let the guitar player dial in the amp. He also added some front end pedals that have seen better days, some control knobs were broken off. Not really sure it was working. Note that the Badlander does not normally sound so sh!tty. The bass player (who is learning the instrument) was also getting bored. I figured I would try to focus my drumming (lack there of) with the bass player. I am not a musician mind you. But I will take any comments good or bad. This is the only recording I have on my soundcloud where I did not play all of the instruments. my apologies up front for calling this music.



This was my seat for the evening: Note the bass rig is not in the picture as this picture was taken before I got the Mesa TT800. I have some old recordings of the Mark Bass JB Player amp I used. So it is a first for getting the Mesa TT800 into digital playback. Note that I have been playing drums for at least 7 years. I suck. I do not practice though. I only man the drums when we jam. I spend the rest of my time playing guitar.

View attachment 1706

Love it or hate it.

If it was not for the Mark V90, I probably would have not bothered to research the old tech on triode circuits and such. I would have to say I learned a lot in doing so and making mods to the V.

You got me thinking on the V90 Subject. Most of the shrill (assuming you have such issue) is with the preamp and not the power sections. I tried slaving into the Roadster and had the same terrible sound. At least that way I was able to isolate the power section to some extent. Then again, the Mark V does not have a good FX send circuit so some of the brittleness could be attributed to the front end of the GEQ circuit which is all transistor driven. Note this is only due to the shrill character of the amp when any distortion is created (CH1 tweed, CH2 edge, all of CH3). Even when you turn off the GEQ, the signal still passes through the complete GEQ circuit. It never gets pulled out or bypassed completely. Based on the schematic, the GEQ off just places a 1M ohm resistor to ground. When it is turn on, that 1M ohm resistor gets shorted out by a JFET.

There was a post by Mesa rep, Theresa on tube color codes and if you can mix and match them. I was curious what the posters were talking about and then it came to reality on the Mark V. Here is the link

https://boogieforum.com/threads/mesa-color-code-plate-current-values-420-vs-440.86620/#post-534638
Keep in mind since the Mark V90 is a Simul-class amp, it is by design that the Class A circuits run on the hot side. This results in power amp saturation. the Class A/B sockets are just like the MWDR, just coasting and providing some enhancement. You were on the right track with the short tubes in the outer sockets and the longer ones in the inside. If they are mesa branded tubes, look at the color codes. Reds or Yellows will have more overhead and least likely to clip as much. If those are in the center pair, it would help reduce the power amp saturation effect. What you use in the outer pair may not make much of a difference. I will have to take a closer look at the STR441 I tossed in the V and see what the color codes are. I do have some survivors left from the V when it was red plating tubes. I will see if they test ok and try them in the V. I am now curious to hear how that sounds.

I have tried many different Mesa branded power tubes. Mostly marked as Green, or Grays as I was seeking a resolve for the JP2C. I do have some yellows on reserve for the Roadster as that amp sounds like crap with hotter power tubes. At least the Simul-Class amps you can swap in power tubes of different color codes, or variants of the 6L6 so it will not dominate the overall tone. I should have kept the Mark IV as that one was great when blending different power tubes or doing the integrated quad (mix of 6L6 and EL34). They did make changes to the extended Class A portion so the bias voltage will not be where it needs to be to run EL34s. It may work though. I had been tempted to try it. decided not to as the bias circuit in my V is messed up to start with. Probably one reason why I will not try the STR415 tubes in that amp.

I did not have any issues with my V as far a bias is concerned and I HAVE a later model so no icepick either (I wish I had an earlier one...I had a Studio Pre and they icepick....I can use an eq an get rid of it...something in the tone when it does that that is missing when it doesnt. Too bad too. My power amp tubes were a complete accident...I like the short bottle 441's better and had them in ...it came from the guy I got it from with the 440's in (recto tube I think)...anyway...one of my 441' blew and through trial and error I got to this and it sounded WAYYY better than any power tube configuration( it is hard to describe....as loud as I turned it up, the amp sounded like it wouldnt be heard...WEIRD..(hollow funny no ***?).and it does not sound like that at all now...in fact it has as good a power section as any amp I have owned (and I use it as a power amp...you can turn the amp to channel three when using the loop to take an external power amp...turn the amp to extreme mode and turn the negative feedback OFF...REALLY neat trick when hooked to a Marshall or my Triaxis (extreme modes whole thing is the negative feedback is removed from the circuit...this happens post loop so you get the benefit when using just the power amp section. )...also I am beginning to think the WHOLE issue is the EQ and tone stack !!!.. My Studio pre had a tone stack that worked...not like a Marshall...but the tone stack gave you differences (not the Mark V one) as a result...and you know this,...the channel will sound different(the studio pre actually sounded REALLY good without the EQ...the MArk V is a MIDDY MESS without the eq)...they are dependent highly on what tone stack is even present...also I am convinced (I use an outboard EQ) that the setting on the Mark V eq are correct as far as placement...but the Q (or bandwidth of each frequency) is SIGNIJFICANTLY different than the Studio pre...give me the tone stack of studio pre with the eq Q of same in the V and I bet I would ne happy at least!! (I use an outboard eq and it makes a difference...I am not so sure the loop is the issue...you get volume drop but it is a master volume circuit and that is the point!! (And WE really do seem to come from VERY similar backgrounds in odd ways!!!LOL)...when you related your story it made me think that it was similar in enough ways that it would make you appreciate mine!!