Mark V, Celestion Cream Alnico 90W

[bandit2013]

The speaker came last week.

I did open the box to inspect the new speaker. First thing I did was tapped the cone to hear the paper. I have seen a video regarding speaker resonance regarding the cone vs frame and the subject was focused on the Celestion Cream Alnico. In the video the one speaker in a 2x12 had a distinctive deep sounding thud vs the other which had a much higher pitch (the one with the higher pitch was causing issues). All sounded good with the cone, also wanted to look at the dust cap and forming of the paper cone relative to what I am used to seeing with the V30, G12H75 Creamback and the C90. Cone forming is very similar to the G12H75 Creamback or V30, take your pick. The dust cap also seems to have a different elliptical shape vs the soft dome shape.

I was not ready to install it yet as I was not done with the Jensen Jet Blackbird and was waiting for new tubes to arrive so I can get some good recordings. Oh well, the new tubes did not make that much of a difference in character except that the power tubes seemed to have a late distortion as it was too easy to clean up the CH2 with high gain settings by rolling off the volume on the guitar. Not sure I was liking that. The change in tubes did make a difference on the bass response and when pushed it sounded just as great as it did with the old SED =C= 6L6GC. Much tighter response and no more barking. I was not sure I was going to install the Celestion as I was enjoying the Jensen too much. Then I noticed a bit of fuzz and at lower volume and a G note on the low E caused a buzz that was bothering me. Was not sure if it was Tube related or what. Pulled the RA100 Combo close to the Mark V and connected to the RA speaker. Not tube related noise. I was also holding the tubes (at the end where it is not superheated) also removed the tube cage to eliminate sources of rattle. I could not put my finger on it, also I was planning on tube rolling by removing the chassis for better access to the preamp tubes (just did not want to remove the power tubes over and over again). I was able to narrow down the source of the buzz. It was the ALNICO puck (actually the steal endcap on the magnet). Enough reason to swap speakers.

I was not overly impressed with the Celestion Cream Alnico 90W at first. I was really interested how the RA100 would sound through it so I channeled the RA to the Celestion Cream with a modified extension speaker cable I made just for that purpose. So the first notes rung out though the speaker came from the RA100. It sounded a bit thin but that could be the RA100 or the fact that the Mark V chassis was not installed at that time and the cabinet was completely open. I wanted to tube roll the Mark V before installing it back into the shell. Wound up with all stock tubes again except the PI. Figured, at least that is a good benchmark to start with. Also wound up removing the new power tubes since I rather burn up some old ones while breaking in a new speaker. For a green speaker, it sounds great. bottom end is much tighter than the Jensen and the top end has more precence but not overly bright which to me is good as I do not like ice pick. Having all stock tubes (power tubes included) except for the PI (sovtek LPS) I am impressed with the overall tone. Actually this has to be the first time I actually cared for a Mesa power tube in the Mark V as I find them to be overly dark. There are some similarities of the Celection Cream Alnico 90 to the Jensen Jet Blackbird with the CH2 and CH3 with mild to moderate gain settings. They almost sound identical except that the Celestion has a bit more presence in the midrange. I felt that the Blackbird was more forward with pick attack than the Cream. Well, I am comparing a green speaker to one that was almost broken in. The huge difference is with the clean channel. The Blackbird really shined here with piano like tones (depends on what guitar I am using). The Celestion Cream was a bit glassy (not brittle by any means but more so in terms of feel than sound). How about liquid vs dry. I will contradict myself here, liquid in terms of the top end, dry at the bottom. Hard to describe it actually. Perhaps woody may be a better term as the character is similar to that of a vintage speaker with a paper voice coil. I do like the Celestion Cream Alnico 90W as it seems to be a better fit for the Mark V (as if this was the intention of Celestion) also fits my music style more so than the Blackbird. Sooner or later I will get to some recording of this new paper doughnut.

 

[bandit2013]

What is similar about the Celestion Cream Alnico 90W to the Jensen Jet Blackbird as well as the EVM12L is the speaker gasket. Made of layered paper so it is hard material. Celestion did make a slight difference such that the top layer of the gasket is coated with wax or some other form of slippery material. I was hoping for a rubber like cork or closed cell foam like the other Celestion speakers utilize.

It does sound really good with the Mark V. I am a bit surprised how pronounced the bottom end is with the smaller voice coil, the Jensen took some time for the bass to blossom especially with higher gain settings. There does not seem to be any compression in tone with the Cream Alnico as there is with the G12H75 creamback speaker. So far, the Celestion Cream Alnico 90W speaker has not been a disappointment but I am sure to find out sooner or later if there is something to discover why I usually prefer speakers that have a higher power rating than the amp output. In comparison to the C90, almost similar but not exactly the same tone. I did have the master (using the FXloop enabled) at about 11am which seems to be a sweet spot in getting the power tubes to saturate with the right amount of grunt. Yeah my pant leg was moving from the air pressure. One other thing I notices with this expensive paper weight is how I really liked the amp in 45W mode on CH2 with the Tube rectifier. I actually had to check as it did not seem weak in output as it usually seems to drop a few dB with the tube rectifier vs the silicon diode.

I will try to get some recording of this speaker in the Mark V combo this weekend. Too bad I do not have an MC90 for a reference to record as a benchmark (recorded music usually does not sound exactly the same due to some losses and tonal influences from the mic).

 

[bandit2013]

I was able to manage something of a recording. I was not quite ready to do this.... :roll: I am surprised the tube rattle did not make it into the mix which is good to know. I have been battling the tube rattle issue with the Jensen Blackbird as well. The new tube I did get were silent in terms of mechanical noise but they had too much headroom for that power tube gain grunt that is desirable and I did not want to push the amp too hard as the speaker is still green and not broken in yet. Come to think of it, the Celestion Cream ALNICO 90W would work well if paired with the Jensen Jet Blackbird. They are similar on tonal character with some mild differences. Too bad I was too lazy to get out the condenser mic as that would have produced a more accurate recording than the SHURE SM57. I did have to tailor the tone a bit so it matches closely to the real deal. The SM57 seems to color the tone a bit but not much. What I do like about the Celestion Cream ALNICO is the added warmth of the midrange that enhances a mahogany guitar. It is not as dramatic as say a V30. If the speaker holds up to the Mark V I will be very happy. I was not sure what to play so I just threw something together that I thought would at least give you an idea of its tonal range and gain handling characteristic.


https://soundcloud.com/user-353100000/mkvcrm90alnicomkivwav

 

[bandit2013]

I think I like the Jensen Jet Blackbird a bit more than the Celestion Cream (hard to compare a broken in speaker to a green one). I might put this in my other practice amp for a while just to get a feel what it sounds like with EL84 power tubes. I did not like the Jensen with that particular amp. In either case, I actually prefer V30 or the G12H75 Creambacks with the RA100 head or Combo. The Celestion Cream ALNICO is quite similar to the Jensen Blackbird ALNICO with some subtle differences, such that I prefer the Jensen over the Celestion. Either way you go, they are both great speakers worthy of trying. One speaker I have tried that is quite similar was the WGS BlackHawk HP 100. It sounded really good when it was green, but the Mark IVB did it in during the break-in period. The smell of burning phenolic resins was the giveaway that I over powered the voice coil with an 85Watt combo. For some reason or another, the Mark IVb was hard on speakers compared to my other amps.

 

[bandit2013]

After swapping the Celestion Cream with the Jensen, they almost sound so close it is hard to tell them apart. Actually they are not that close. Not sure which one I like better... I am tired of chasing the speaker balloon.

 

[bandit2013]

Things are not going so well. Played the Jensen for a bit, installed the new power tubes and figured I would give the Celestion more time and it did not sound as good with the new tubes( came close to the tone of the WGS Black Hawk HP100, HONKY or too much midrange to be desired. Mesa branded tubed on the other hand sounded great with this speaker, they were not too bad with the Jensen. Went to put the Jensen back in and shoved one of the mounting bolts through the cone when the speaker shifted out of place. It is only a small hole an probably would not cause any concern. By the time I placed 7 of the 8 bolts I changed my mind and decided to go back to the EVM12L speaker. What sounded sterile before sounds really good. New tubes do make a difference.

As for the Celestion Cream, I will install it in my practice amp and see how it sounds with EL84 tubes.

Oh well, No more speakers for me.... Well at least the Celestion G12H75 Creambacks were a good fit with the RA100 Combo. I did try the Celestion Cream with the RA100 combo with extension cable, thought the speaker sounded too dark with that amp. I may end up selling the Mark V for a JP-2C head, would love to see that in a 2x12 combo version.

 

[Nicklotsaguitars]

I'm currently re-thinking my opinion of the C90. It doesn't work with the MkV for me, that much is clear. Yesterday before setting off to a gig that had some very nice Blackstar backline provided. I took my modded KK head and plugged it into my MkV combo to test it. I'd recently got it back from a band I'd lent it to while their guitarists old 900 was getting fixed.
It sounded godlike through that openback 1x12.
Why does it work with that an so well with not the MkV?

 

[bandit2013]

That is a good question, I have always wondered the same thing about the MC90. It is a good speaker and actually preferred this with my V3M combo amp. All I have left of the MC90 is the magnet which is the only part I decided to keep when I tossed it in the trash. I would not throw away a good speaker, but the one I had that came with the Mark V combo shell had some defects (deformed cone due to bent frame and separation of the dust cap, attempted repair but could not get a good sound out of it). Even the Jensen I put a hole in on the side of the suspension is still a good speaker that can be repaired.

The MC90 has a better response with different power tubes vs the Mesa branded Ruby 6L6GC-MSTR. The converse can be stated about the Celestion Cream ALNICO 90W, this speaker excelled with the Mesa 6L6GC STR 440 tubes. However, with different power tubes that have a bit more headroom and require much more to bring into saturation, the low end will dominate (which is typically the issue with most amps) and the mids may become more apparent in the mix of signals ringing out in the paper cone. The Jensen on the other hand definitely had an endless bottom and if the power tubes were weak or lacking the low signal drive (which usually consumes more power than higher frequencies) it will bark out some notes that are defined but yet unexpected. I found the Jensen to be more forward with pick attack and with that the bottom end would pop out a note when saturated while palm muting. Too precise for me as my technique is not that great. The Celestion Cream 90W alnico was a bit more forgiving. I was impressed how dark the speaker was, but it is also bright too, much brighter than the Jensen. Usually where I like to push the Mark V is somewhat hard on most speakers. MC90 would breakup and not provide the tight thug for palm muting. The Celestion Cream was great and delivered what I wanted with the Mesa power tubes, but did not seem flexible for others. I will say one thing, the Cream Alnico remained tight in an open back cabinet. It did not fart out like the V30 if applied in the same combo amp. I went back to the EVM12L black label speaker as I can push the tubes into saturation and not get any break up, mush or barking. Either way, it is all about what you like, so it is all relative. In some regards, the Celestion Crème is similar to the MC90 but seems to retain its composure at elevated volume levels. Also it was a bit too warm for clean (not exactly dry the way I like it) but it did have its merits in sound quality. I am going to give it a try in an EL84 based amp just to hear how it will compare to what I have in there now.

 

[bandit2013]

One thing is difficult to do is select a speaker that will fit the amp in terms of sound quality. I keep gravitating to the EV for the Mark V. Another amp that comes to mind that would probable suit the EV is the Stiletto Deuce. I had one of those for a short time (less than one week) and only had an EV mounted in a 1x12 cabinet. Why I have been trying to move away from EV speakers, well, it does not work with RA100, Sounds great with the Roadster but wanted more midrange in my tone (recently modified my old recto cab with two EV mixed with V30 as this seemed to work out much better than all 4 EV or 4 V30). The EV speaker is much heavier than the others, magnet size is very large and makes for tight fit and ease of tube replacement. But for the Mark V combo, I just cannot get a better speaker that fits my needs. I generally play loud and want something that will hold up, provide the tonal qualities and harmonic content. I really thought the Jensen was it, but was a loose on the bottom end, not much as the notes were well defined. Perhaps the forward pick attack was the why I liked it and disliked it (especially with palm muting). The Celestion Cream sounded spectacular with the Mesa tubes but seemed a bit mid focused with other tubes like TAD 6L6GC-STR (I am using the Preferred series tube which is similar). With the SED 6L6GC (=c=), excellent with the Jensen and EV, and still retained that Mark grunt with the Celestion (too bad the tubes were used up). I did not select the Jensen or Celestion speaker because they were similar in tone to the EV, it just happened that way (note that the Cream is just similar but with more mid content). As for Edge mode on CH2, nothing really sounds good with this voice, but the EV is not as tin like as it was with the Celestion or thin and weak as it was with the Jensen. Perhaps I just have not discovered how to set up for that voice. I spend most of my time with the Crunch maxed out or in Mark I mode when I use CH2.

They are all good speakers, however I think the EV will hold up much longer than the others with a 90W simul-class amp. If this combo was a 2x12, I am sure I would have found something else that sounds good. EV is not the best either as some like it, and some do not. I just prefer to have what I remember was in my Mark III (never had to change the speaker in that one, and sold it with the original still intact and working as it did the day I bought it 24 years ago. Too bad the tubes did not last that long).

 

[bandit2013]

I was playing the RA100 combo for a while today. This reminded me why I have been chasing the speaker balloon with the Mark V. I got the bug when I swapped the two V30s with Celestion G12H75 creambacks and was blown away on how different that amps sounded, especially with Mullard reissue EL34's that poured out gobs of gooey midrange with just enough bass and treble that I would have to force myself to stop playing. If you have not been down this road you may not understand the frustration or reward one can have finding that right speaker for your amp. I may have pulled the Celestion Cream Alnico 90W out of the Mark V but that does not mean I am done with it. The Cream is similar to the V30, C90 and EVM12L as if it was all rolled up into a final speaker hybrid, which is what it really is. It does have a vintage flavor to it but yet sounds modern depending on power tubes in use. Shoulda, woulda, coulda tried it with EL34s :shock: I did not thing of that actually. The Mark V has its own distinct primary tone and it does not matter what channel you use as you can clearly hear it, perhaps it is the different bias on the class A power tubes and the colder bias on the A/B simul-class design. Unfortunately, I do not believe the Celestion Cream Alnico 90W was the best choice for the flagship Mark series amp as I like to have flexibility in what tubes I install. If I could find a quad of Mesa tubes that did not rattle I would be happy with the Cream 90W speaker. Not just a mechanical noise due to the speaker vibration but tube sing at low volumes where the plates in innards of the tubes would vibrate due to the change in signal current and associated electromagnetic fields. At low volume I could hear the tubes singing away louder than the speaker was outputting. When I am playing a rich clean channel I do not want to hear that. It will not make it on a recording unless you mike from the rear of the amp. One thing to note about the Celestion Cream is that it sounded great, no flub, no buzzy sounds at low volume and it worked very well in an open cabinet (combo in my case). The Jensen is similar in that regard but I did notice a bit of buzz when using the 10W settings, could be due to steel frame resonance as the back side of the frame has more suface area compared to the Celestion. I would definitely recommend the Celestion Cream Alnico 90W or the Jensen Jet Blackbird Alnico 100W as a replacement speaker.
My next task with the Celestion is to try it in an EL84 based amp (sorry it is not a Mesa) but I may report about it just for kicks.

I may return to the Celestion Cream installed in the Mark V when I get my hands on some EL34 tubes that are not noisy. Unfortunately I cannot use the Mullards RI EL34 in the Mark V, (tubes nearly red plated on me 5 seconds after switching the standby swtich). The Celestion Cream or the Jensen did not win me over with the RA100 channeled into it. I was hoping it would expecially with the Celestion.

 

[bandit2013]

Well, um, not exactly done with the Celestion Cream Alnico 90W and the Mark V. I never got around to installing the speaker into the other amp. Instead, I changed my mind and put it back into the Mark V after I discovered the new tubes were not as good as I first thought them to be. Also, moving from the EV back to the Celestion made me appreciate it that much more. I was also able to match up 4 good Mesa 6L6 tubes ( I had some extra tubes I had forgotten about that matched the color code of the quad I already had so that was good in some way...no more rattle noise, at least for now :roll: )

I could have put the Jensen back (even though I punched a screw though the webbing it would not be noticed, this can also be repaired). However, I liked the bass response with the Celestion speaker much better as it seems to be tighter than the Jensen (I believe the Jensen has a lower frequency response than the EV - assumed or perceived) Also palm muting is more desired with the Celestion than the other speakers. Open chords they all sound about the same. So the story continues and hopefully it will be a good one and not a complaint or discussion why you should not do this at home, etc....

 

[Grundletaint]

Is there a weight difference vs the stock speaker?

 

[bandit2013]

The Celestion Cream Alnico 90W weighs 9.3lbs. It differs in weight by 1 lb. Not exactly sure what the MC90 weighs since I no longer have it (similar to V30 10.4lbs) and compared to the EVM12L at 16lbs (not a stock speaker). So the overall weight of the Mark V combo would weigh in at 64lbs, not much of a difference there to be noticed.

I am still uncertain how it will hold up to the 90W power of the Mark V. Thing about combo amps is the tendency to raise the volume up considerably since there is less air movement than say a 412 cabinet so the perceived overall volume is less. I am actually enjoying the speaker for what it is worth and I hope it can last a long time. I have to keep reminding myself that this is still a green speaker and not broken in yet. It just sounds so good that I keep turning up the volume for more. I may have stated previously that I thought the Jensen Blackbird sounded better on the clean channel, that is subjective at best. The Celestion seems to have a more vintage tone with the clean channel (more of a fluid bluesy tone with some bell like chime that rings out but subtle not dramatic) such that I am actually liking it more I play on the clean channel. Sounds really good on CH2 and CH3 and it does not seem to matter how much gain you throw at it. So far it stays very tight and tracks the bass quite well. I have not been able to get the mud in there which is good, a V30 under the same circumstances (open back enclosure) would get muddy and loose its composure which is the issue I had with the RA100 Combo and reason for changing speakers to the G12H75 Cream backs. However, I did not like the Celestion Cream Alnico 90W driven by the RA100 (at 50W) as it seemed a bit too bold on the bottom end of the spectrum. I will have to give it another try after I break in the speaker. Also have not tried to run the Roadster through it yet either. Tempting but uncertain how the speaker would perform in a sealed cab, may be a good choice to mix with V30 in a 412, or just have 4 of the Cream 90W but not ready to spend that amount of coin yet.

 

[bandit2013]

I am thinking on getting two more of these for my 412 and mix them with the V30's. Right now I have a pair of EVM12L I the 412 as that helps tighten up the cab when I use the Roadster. I believe the Celestion Cream would be a better fit than the EV. Before I jump on that expense, will have to hear the Roadster through it first. I did plug in to the RA100 combo for a bit, then returned back to the G12H75 Creamback. Not sure which one I like better. Also wonder what the Celestion Cream will sound like in a sealed 412, if the 1x12 wins me over with the Roadster as it did the Mark V, may have to get 4 of them instead....

 

[bandit2013]

The Celestion Cream Alnico 90W did not win me over with the Roadster. It does sound really good so not compliant there. I like it better with the Mark V as a single 1x12 combo. Perhaps another in a decent extension cab would be good too. I have not used the Roadster that much since I have been playing the Mark V with the different speakers, as well as the RA100 Combo. I did spend more time with the Roadster head on top of the RA combo and compared the Celestion Cream Alnico 90W to the two G12H75 Creambacks. The winner goes to the G12H75 Creambacks. Adding two of those to the 412 cab in an x patterd with two V30 would sound killer. I did not realize a change in preamp tubes would make that much of a difference in the Roadster. It was great before but now sounds even better and the G12H75 Creamback can deliver that throaty punch perfect for Heavy stuff and yet can still dish out some great clean sounding tone, may not be as spectacular as the Jensen Blackbird or the Celestion Cream in an open cab. Aside from tone, the Creambacks are a bit more affordable than the Celestion Alnico Cream to load up a 412 with. I am more on that quest to find what works with each amp (and I can always hook any of them up to one or two 412 cabs.)

 

[bandit2013]

I have been playing the Mark V religiously since March 24 with the Celestion Cream Alnico 90W and have yet wanted to remove it. It is similar in character to the Jensen but tames the bottom end more as it remains tight vs loose. As for tonal qualities, it has improved considerably after break-in. At this point in time, I think I am done with chasing speakers as I am very pleased with the Alnico Cream. It holds up quite well with the Mark V as I normally use full power at 90W when I play. To date, this speaker has yet to break up or reveal any abnormalities that would result from driving it near its capacity. The Jensen would begin to bark at elevated volume levels such that I was not convinced it was tube related (at first I thought it may be weak power tubes and it was not). The love affair with the Mark V is still going strong with the Celestion and so far the honeymoon has not ended like it did with the Jensen. Note: the barking noise I was getting was reason for the getting the Celestion as I had not had this issue with same tubes with the other speakers. I did find a good home for the Jensen so no waist on paper cones and magnets. Note: the Celestion has more mass to it than the Jensen despite the large bell. Not sure how big the puck is as I do not want to remove the bell on the Celestion speaker. Now I can focus on playing and enjoying the Mark V for once without wanting to change something.

 

[bandit2013]

After 6 months of hard use, all it took was a hook up to the JP-2C just to hear it, sounded okay but not best choice for a JP-2C.
Was playing for a bit with the Mark V as I was comparing it to the new amp. I started smelling that unwanted scent of burning resin, no smoke or anything of that nature, not as strong a phenolic resin of a resistor body overheating but the odor was familiar as I have encountered this before with other speakers.
I believe the voice coil has overheated, can only smell it with strong low chords. Went to feel the bell, hotter than hell. Also notice the tone was getting darker too. I am afraid this may be the end for the Celestion Cream 90W Alnico speaker. Such is life. Not exactly sure if it was the Mark V or JP-2C that did it in (swore that I used 60W mode but perhaps it pushes a little more than that at its peak as the OT on the JP-2C is probably the largest I have seen shoehorned into such a small cabinet. I did not compare case sizes between the two but the one in the Mark V is much smaller.

I guess I have to install the EV and be done with it. :evil: Speaker still works and sound great after letting it cool down, still has the burnt voice coil smell when I play it. It very well could be something else too, failure in the amp somewhere as the odor seems stronger near the 5 band EQ where the grill meets the chassis. first time I found the bell to get hot on this speaker. That happened with the WGS BlackHawk HP100 when I had it in the Mark IV for a short while. Perhaps it is too early to tell if the speaker was toasted or not. If I get the same smell with the EV installed, probably something else.

 

[bandit2013]

Perhaps the Cream Alnico is not damaged after all, It is something in the amp that is running hot, so what I smelled was not the speaker but what? If I burned the voice coil I would be able to smell it though the dust cap. I was also getting poor performance through the EV speaker too. Though the 412 cab, the amp never sounded better? Interesting...

 

[bandit2013]

I put the Celestion through its paces again....I played for two hours without any problems. CH3 (all settings) no issue. Bell remained cold. Clean channel, no issue either. It does get warm when using the CH2 but have not noticed the hot smell. Thermal changes may be in part due to heat from the tubes since the bell is close to the power tubes. I found that the Jensen Blackbird would get warmer as the bell is much larger on that speaker than the Celestion Cream. Still sounds great so I will use it until it dies or something fails. The EV speaker I reinstalled after the first problem did not sound very good, for some reason it needed higher volume settings. Could it be the OT? My bet it is the power tubes since I changed all the tubes to stock so I can compare out of box tone to the new amp (IP-2C). If the speaker does fail, I would probably get another to replace it or sell the Mark V Combo as this amp sounds great with this speaker. Either that or get another head shell and abandon the combo format.

My bias mod was not done in terms of using a current probe on the tubes, that I need to address and will have to get a bias probe just for ensuring tubes I am using will work with the amp or my other amps. The Roadster, I keep stock tubes in that. Tried some different power tubes to get a good idea how it sounds, the Mesa STR440 work the best in that amp. However, with the same in the Mark V, it sounds more like the RA100 in tone, almost like you were running some early gain EL34 in RA100, in other words the Mesa STR440 seem to annunciate more of the midrange frequencies. Back to what I did to the Mark V, since I was having issue running the Mesa STR440 tubes in the amp, (tip of red plating on the center pair) I took a gamble after reviewing the schematics and decided to raise the bias voltage based on the calculations and printed voltages. I replaced the 82k resistor with a 1% 100k resistor. That allowed me to run the Mesa 6L6GC STR440 in both power modes (full power or variac) and 90W or 45W (45W was a sure kill for this type of tube). I did realize this may cause the outer pair to run colder which is not a good thing... Yesterday I took the amp into work to replace the bias resistor to one much closer to the 82k value. I could easily install a pot to make it adjustable but not what I want to do at the moment as I prefer the fixed bias since that will not drift as much (resistors do change value due to heat, not much but depends on component 100ppm/C or better as most are usually much higher than this and will have more drift). Most pots have lousy tolerances and much higher ppm/C. The new resistor 91k was an improvement as the bass response became tighter that it did with the 100k, also the amp is not brittle in tone either. The 82k bias resistor just made the amp unusable, if the tubes did not red plate, the amp was so terribly brittle even with all the treble dialed at its lowest position, presence basically off, and the gain set to lower values (if set above noon on either CH2 or CH3 it sounded terrible). I have much better control of the GEQ and can dial in treble and set overall tone with the presence control. Why am I writing this..... The Celestion Cream Alnico 90W speaker is why I am keeping the Mark V as it sounds so good with this amp. I did compare the revised biased configuration though the 412 cab loaded with V30 and though it made a huge improvement, actually sounded really good so if the Celestion craps out the alternative would be to go back to a head format. I wish I never sold the head shell :x as I knew this time would come eventually. I would not recommend you to alter your amp. I am sure most of the Mark V amps sound really good. If you have red plating issues or sounds so brittle and unusable above bedroom levels, I would recommend you take your amp into service for inspection and repair. I am not against fixed bias amps by any means, but there may be some out there such that the sum of the parts do not equate to ideal operating conditions. Yeah, need to get some bias probes or kit so I can at least see where this amp is running at, is it too cold or too hot? or both. Considering I have owned 7 different Mesa Boogie amps (includes the Mark V) and never had this type of issue as I do the with the V. Most enjoyable amps : JP-2C , Roadster, RA100 head/combo, including what I sold Mark III combo blue stripe, Mark IVB combo. Yeah I have red plated many tubes in the Mark III but that was relative to its use as I was in a band for a while. After that was over, never had an issue with the MKIII. As of late, I finally got the Mark V sounding almost as good as my other amps (sometimes I think it even sounds better after the last change).

 

[bandit2013]

I have my reasons why I love the Celestion Cream 90W Alnico speaker. For one it sounds like a blend of EV and V30 if you can imagine that, has similar traits to the MC90, but yet I feel it replicates the complexity of tone and character I get from the V30 loaded 412 cab but without flub or overly iced top end. It does have a vintage tone to it but yet excels when the gain goes up, and to make it even better I can get all of this with a 1x12 open combo. If I do get another Celestion Cream 90W Alnico speaker it would replace the one in the Mark V combo, and the other one end up in a 1x12 wide body cab. I may just buy one and use the MC90 in it to get a feel how that would combine. The MC90 that came with the Mark V combo Shell that I bought from someone had some issues, flub and just not a good fit but I am sure it has seen better days before I got it. I had it in my Carvin V3MC for a while and then decided to install it into the Mark V combo as I was tired of the EV. The Dust cap became partially separated so I re-glued it back on. Unfortunate for that speaker it sounded like a damaged voice coil. I did save the magnet though but wanted to see for myself if there were any thermal signs on the voice coil. Nope, actually looked good. Before I took it apart, I did put it back into the V3MC only getting the same results of scratch ugly sounds. Jensen Blackbird is also a great speaker but seemed too dark or similar to the EV for my taste. It fit into the V3MC without need to remove the bell cover so there it will remain. (oh I ended up poking a screw though the web of the speaker when I was swapping that with the Celestion. Perhaps not for a blind comparison but for a blind install as it were, ooops... which is a kind and gentle description what I really said when that happened. No fear about the Celestion, as I already paid for it, curious though to see how long it lasts. A characteristic of ALNICO drivers as they will heat up due to change in magnetic field as I recall reading somewhere if it is so true. Seems the more bass laden tone of CH2 does make it warm, it will get hot if the send level is maxed out. When I had the chassis out I did look at the visible components for signs of thermal stress where the odor was coming from (area around the 5BEQ). Too bad the Celestion Crème 90W alnico is not rated for 100W to 150W. But so far still operating and sounding great despite what I though may have been the onset of EOL of the speaker, not sure if this is EOL of the amp as I have had many issues with it over the years and would not surprise me. Too bad as I am really loving it at the moment. So if an when the speaker finally fails I will resurrect this thread and make the announcement.