Mesa MarkV / Saturation 'mod'

[Jfriley]

This thread is like an early Christmas present! I was literally test driving a JP-2C yesterday as a possible upgrade to my Mark V:35, but I think I MUST try this before letting go of close to three grand. I’ve read through this thread, watched the YouTube videos associated with the ideas here, and corresponded with a couple of people, but I still wanted to make sure I’m getting the basic concept of this down.

I know a bunch of you have tried this on the V25 and V35 models. Is the difference really THAT noticeable? From what I understand the 12AT7 tube will go into the V2 slot of the 35 (V4 slot on the 90 watts). This is all I need, correct?

https://www.sweetwater.com/store/search.php?s=12AT7&Go=Search

If I read this thread correctly, the AT7 is lower gain than the 12AX7, but somehow that opens the tone wide open and allows for the overall higher saturation sound?

As far as actual installation, do I have to take the whole thing apart or can this be swapped out by hand?
Sorry for the silly questions, I’ve just never messed around with the tubes before.

 

[Markageddon]

This thread is like an early Christmas present! I was literally test driving a JP-2C yesterday as a possible upgrade to my Mark V:35, but I think I MUST try this before letting go of close to three grand. I’ve read through this thread, watched the YouTube videos associated with the ideas here, and corresponded with a couple of people, but I still wanted to make sure I’m getting the basic concept of this down.

I know a bunch of you have tried this on the V25 and V35 models. Is the difference really THAT noticeable? From what I understand the 12AT7 tube will go into the V2 slot of the 35 (V4 slot on the 90 watts). This is all I need, correct?

https://www.sweetwater.com/store/search.php?s=12AT7&Go=Search

If I read this thread correctly, the AT7 is lower gain than the 12AX7, but somehow that opens the tone wide open and allows for the overall higher saturation sound?

As far as actual installation, do I have to take the whole thing apart or can this be swapped out by hand?
Sorry for the silly questions, I’ve just never messed around with the tubes before.

Straight, regular tube swap.
4 main bolts on top of the unit off, Chassis out, find V2, take out the 12Ax7 in there, and bring out your 12AT7... The pins on the mesa ones i've used are slightly angled inwards when you get them, but take care in lining it up with the holes and gently rocking it in to position and it'll ease its way in. After that you're gold. Just slide the chassis back in, and line up the bolts with the holes, drop 'em in, screw em back up. And you should be good to go.
No cuts, snips or solders involved, minimum hassle..

More small amp install specifics here:
https://forum.grailtone.com/viewtopic.php?f=33&t=68808&start=45

And yep thats the dynamic alright, like I said...!

And Merry Xmas

 

[Jfriley]

Ordered! A little VERY last minute Christmas present to myself. I'll let you know how it goes.

 

[Markageddon]

Ordered! A little VERY last minute Christmas present to myself. I'll let you know how it goes.

Excellent.... congrats...!
Very very smart move for the festive season.

 

[bandit2013]

Wayno, Very glad to see you got your amp back in working order. Cheers to you and Merry Christmas a few days late...

 

[Wayno]

Wayno, Very glad to see you got your amp back in working order. Cheers to you and Merry Christmas a few days late...

Cheers, merry Christmas and a rockin new year.

 

[Lkdog]

Have been chatting with Bandit about this.

I bought a used MARK V unit and it had a Jan/Phillips 12AT7 in the V6 slot.

It sounded good, but he encouraged me to try it in V4.
Have to say it makes quite a change for the better at least to my ears.
Smoother, punchier, and improved in all three modes in Channel 3.

Great tip. :mrgreen: :mrgreen:

 

[bandit2013]

If you just got the amp, you have a lot of exploring to do. The 12AT7 in V4 does revitalize the distortion characteristics of CH3. If you have a spare 12AX7 tube, stick it into V4 and see what happens. All depends on production year the amp was made. I have played though newer version of the Mark V and thought that sounded really good compared to my 2012. (my opinion on my Mark V is bipolar at best, perhaps boarder-line manic depression / :x ) Perhaps the 12AT7 was the Valium I needed to cure my Mark V woes. At best, I think my Mark V has Encephalopathy (a much easier word to spell than to pronounce, also try saying it while holding your tongue. :roll: (I did not sleep well last night, my apology for the odd post).

 

[bandit2013]

I have listened to some recordings of the Mark V:35, not really sure why one would want to use a 12AT7 in that amp. If my Mark V sounded like that I would have left it alone. I thought it sounded great as is. I only see this thread relative to the older model Mark V (which is long overdue for some upgrades).

 

[Boogie Monster]

Hello all, I’m new here but have been following for a few years. Lurking is done now. My New Year’s Resolution is to engage in the forums I look at. So here goes

I’m so glad that I found this thread! I’m a big fan of the 12at7 in v6. I have only tried the experiment with a Groove Tube at7 not the Jan yet. For this particular tube, I like it more in v6, not v4. It seems to get along better with my set up better for my ears.

The biggest reason that I like it in v6 is that I really like the response I get when flipping back and forth on the pentode and triode option. I have never gotten along well with the Triode setting but I’ve been reinvigorated with this as of late. I absolutely love it. To me, it is the aggression and clarity I want and just slightly smoothed out. Especially at volume. It drastically changed the feel of my amp and I wanted you guys to know about it!

Thanks!

 

[Wayno]

Hello all, I’m new here but have been following for a few years. Lurking is done now. My New Year’s Resolution is to engage in the forums I look at. So here goes

I’m so glad that I found this thread! I’m a big fan of the 12at7 in v6. I have only tried the experiment with a Groove Tube at7 not the Jan yet. For this particular tube, I like it more in v6, not v4. It seems to get along better with my set up better for my ears.

The biggest reason that I like it in v6 is that I really like the response I get when flipping back and forth on the pentode and triode option. I have never gotten along well with the Triode setting but I’ve been reinvigorated with this as of late. I absolutely love it. To me, it is the aggression and clarity I want and just slightly smoothed out. Especially at volume. It drastically changed the feel of my amp and I wanted you guys to know about it!

Thanks!

Welcome on-board. Glad this thread helped you along. Keep on rockin. What sort of tone have you got dialed in?

 

[Markageddon]

I have listened to some recordings of the Mark V:35, not really sure why one would want to use a 12AT7 in that amp. If my Mark V sounded like that I would have left it alone. I thought it sounded great as is. I only see this thread relative to the older model Mark V (which is long overdue for some upgrades).

The 35 definitely felt and dialled differently to my friend who has one. He has a very discerning ear and feel gauging perception too. He loves it vs stock..

 

[Boogie Monster]

Welcome on-board. Glad this thread helped you along. Keep on rockin. What sort of tone have you got dialed in?

Thank you for the welcome!

I am loving the heavy tones I’ve gotten. I think the triode setting, for me is a real option now.

We are at the end of our vacation and back home to Michigan by Wednesday evening. I have a pentode/triode clip that I can share. I don’t want to mislead with words, I will post that for us

 

[Wayno]

Excuse the really sloppy playing, the sloppy phone mic sound that cuts both the top and bottom frequencies out, the sloppy tuning etc. Just a quick example of how aggressive ch3 extreme is now! Really could do with more poweramp volume to get the blanket off but that would just distort the phone mic. Will get round to recording something properly sooner or later, just was too cold in my garage after jamming to CD's for an hour and just wanted to get something quick before my fingers gave up completely. Just to give a quick impression of how angry she can sound now :twisted: :twisted: :twisted:

https://drive.google.com/open?id=1_3Y9N_w3_GGZJZaicn2Wrre55jSn1Hsz

 

[Markageddon]

Whats that?!? Is that the sound of the recto 2x12 calling you....?

Sounding meaty through the combo...

 

[bandit2013]

I would agree... Sounds dark and sinister. What were your settings? and is that an MC90 in the cab? Also do you have a 12AT7 in V6?
Things will get even better if you had a 1x12 extension cab to go with it. The amp does take on a slightly different character using the 4 ohm jacks when running two speakers. Heck you can even do that with the one speaker in the combo if you wanted too. (That is in the manual by the way). Good to hear the amp is up and grinding away

 

[Wayno]

I would agree... Sounds dark and sinister. What were your settings? and is that an MC90 in the cab? Also do you have a 12AT7 in V6?
Things will get even better if you had a 1x12 extension cab to go with it. The amp does take on a slightly different character using the 4 ohm jacks when running two speakers. Heck you can even do that with the one speaker in the combo if you wanted too. (That is in the manual by the way). Good to hear the amp is up and grinding away

Off the top of my head settings where;

Extreme mode / bright on / 90w / triode
gain: 3 o'clock
treble: 2
Mids: 9
bass: 10
presence: 11
Ch master: 9
output: 9
Pretty standard V on the EQ.
Schecter with EMG's.

I believe these are the settings, maybe a bit wrong in the tone controls but switches are defo accurate. MC90 speaker and Jan/GE AT7 in both V4 and V6. V1 Tungsol, V2 Mesa JJ, V3 Sylvania, V4 Jan/GE AT7, V5 Sylvania, V6 Jan/GE AT7, V7 Sovtek LPS, JJ EL34ii power. C39 mod. Gonna have to re-audition the V4 and V6 dilemma now with the C39 Mod. Agree the clip does sound dark, darker than it did in the room, phone mic knocking off the high end i believe. Very aggressive sounding though which was absolutely what i was going for in the freezing confines of my garage haha. Looking forward to getting together with the band soon and hook her up to my 2x12V. Gonna have a play around with iV mode next opportunity, hopefully settle on a tone i like then experiment with V4/6. Then, with a little luck, i'll be set with a great clean tone, a great rock tone and a great metal tone. Happy days.

 

[mace]

Thanks for the sound sample. On a side note, you‘d maybe be surprised at what the iPhone‘s mic can take. It really takes a lot to make it clip (at least the 4S or newer). So, let it rip!

I‘ve been enjoying the V4 AT mod. I need to remove it and see what it sounds like again, since I‘ve had the Jan AT in V4 there for many months now. But, I need to make some good recording, maybe with a looper as input, and A/B it and flip modes etc. I‘ve also had the SEND level at about 10:30 or 11:00 for several months now as this is more compatible with the FlashBack X4 delay.

A couple of weeks ago I made two changes outside of the amp. I finally got a pedal board and some longer cables for the effects loop. Before, I used 6‘ of cable for two pedals in the loop, and usually about 24‘ total out front with the wah and tube sceamer. Now, with all the pedals on the board (which is something I should have done years ago), I am running 5 pedals in front of the amp and 3 in the loop. There is also now about 50‘ of cable in the loop (just to practice with what I will likely gig with) and 40‘ in front of the amp. So, more cable now and more pedals, more signal loss. But, the funny thing is, I‘d swear the amp sounds a bit warmer and can be dialed more open (more presence and a touch more treble) without being piercing at loud volumes. So, maybe another „saturation mod“ is to add more cable length to nip the highs a bit. haha

At any rate, time to put together some recordings to A/B. The difference may all be in my head. I‘m always suspcious of psychoacoustic effects.

 

[Wayno]

No iPhone here, can't stand em. Horrible things. Sony Expedia, great phone, crap mic unfortunately.

Long cable runs = higher cable capacitance. I.E loss of top end. A good quality buffer in your first peddle then true bypass after that before the amp will help. Shouldn't be too much of a problem with the high level of the loop. Maybe lose a little "air" off the top end I would think. I'd be more worried about noise than anything else with long loop runs. Someone correct me if I'm wrong here. Either way, whatever sounds good IS good right! Looking forward to hearing your rig Mace.

 

[APEMAN]

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