Mesa Mark V:25 Tube Rolling

aamefford

The (should be) Committed
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Specifically using a higher grade tube in V1, and lower gain 12AT7’s in V2 and V6. There are some older threads on the Mesa forum and telecaster forums about it. I just thought I’d check in here to see if anyone has done some or all of these tube swaps? It seems like the V6 phase inverter location might allow a bit more movement of the master volumes before it goes from almost loud enough to loud AF. The V2 seems like it might tame the gain a little, especially on channel 2. I’d put a Mesa SPAX7 into V1, which is basically just a 12 AX7 screened for low microphinics.

I’ve finally got all the tubes, so I’ll experiment. I’m just asking in advance, as my skill in playing and dialing in the kinda finicky mkv25 is not particularly great yet. TIA and all!
 
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Whut? Huh?
Ok, I fixed the typos I could find. My post might make more sense now. Probably not enough to change your response though.

Others chime in. Otherwise, I’ll report back as to whether it turns out to be an interesting change, or internet fueled dumbassery.
 
Ok, I fixed the typos I could find. My post might make more sense now. Probably not enough to change your response though.

Others chime in. Otherwise, I’ll report back as to whether it turns out to be an interesting change, or internet fueled dumbassery.
Dude! You did it!!! You just made Bogner's post actually be correctly capitalized for the first time in recent memory. You, sir, are a CHAMPION!
 
p.s. I did a little messing around with that when I had my V25. I loved that amp when I first got it and "really liked it" when I sold it. I thought it was really close, but lacked the "weight" that comes with bigger glass/iron. I was still going to keep it as my "versatile small amp head" but after getting the Archon I just couldn't justify it. Then I sold it and the guy I sold it to said "I thought you said the tubes were good. I put new power tubes in it and it sounds MUCH better now! Sadly, I had already purchased new Mesa power tubes, but when I decided to sell it didn't put them in. Who knows if it really had "lost" something and maybe I would have kept it if I heard it with new tubes.
 
Ok, so I did the following:
1) Mesa SPAX12AX7 or whatever it’s called in V1. Supposedly a well screened against microphonics 12AX7. This one seems a no brainer.
2) 12AT7 in V2 and V6.

I did it all at once. The end result seems to be a little less gain in channel 1, and the crunch still sounds pretty decent. Channel 2 IIc mode has a really nice crunch as well. It seems like the gain can still be cranked, and it still gets pretty saturated, but it seems to have a more classic rock tone. It also seems to have a (tiny) bit more travel in the masters between ok and way to F’n loud.

Or it’s all in my head. I’ll leave it like this for a bit. I suspect I’ll go back to stock though.
 
Ok, so I did the following:
1) Mesa SPAX12AX7 or whatever it’s called in V1. Supposedly a well screened against microphonics 12AX7. This one seems a no brainer.
2) 12AT7 in V2 and V6.

I did it all at once. The end result seems to be a little less gain in channel 1, and the crunch still sounds pretty decent. Channel 2 IIc mode has a really nice crunch as well. It seems like the gain can still be cranked, and it still gets pretty saturated, but it seems to have a more classic rock tone. It also seems to have a (tiny) bit more travel in the masters between ok and way to F’n loud.

Or it’s all in my head. I’ll leave it like this for a bit. I suspect I’ll go back to stock though.
So.....Was The Juice Worth The Squeeze?
 
So.....Was The Juice Worth The Squeeze?
The jury is deliberating. I’m leaning towards no, other than as a learning experiment. I do like the crunchy tone on ch2 IIc mode though. Was 90’s “metal,” now more like 70’s / 80’s crunch. It kinda frees up ch1 for a fat clean. Big picture, I think all of that is there without messing around with tube swapping.
 
The jury is deliberating. I’m leaning towards no, other than as a learning experiment. I do like the crunchy tone on ch2 IIc mode though. Was 90’s “metal,” now more like 70’s / 80’s crunch. It kinda frees up ch1 for a fat clean. Big picture, I think all of that is there without messing around with tube swapping.
Maybe Your Mark Amps Are Different Than Mine? If I Want Them To Sound Different I Can Turn My Amp Controls Clockwise AND Counter Clockwise And Get Different Sounds. Those Slider Thingies Do Something Too! I Am Not Sure What Though. I Think They Might Could Help. I Haven't Tried Them. ;)

Kidding...

Tube Rolling (In My Experience) Can Be Helpful If You Have A Stash Of Tubes At Your Disposal And Time To Spend. The Problem Is Ear Fatigue And Being Able To Genuinely Remember What The Sound Differences Were (If Any). I Have Made Some Changes That Were Positive When Played Loud Or Quiet And Vice Versa. If A Person Doesn't Have A Tube Stash (Especially With Today's Prices) I Would Refrain From Messing Around Much With Them And Experiment When It Comes Time To Replace Tubes. On Amps That Bias Can Be Adjusted, I Would Always Start There And See What The Amp Is Biased At First. Often Times, They Are Biased Cold And Getting Them In Proper Range Can Make A Huge Difference As Well. I Have Never Been Able To Change Tubes (Power or Pre) On An Amp I Didn't Like And All Of A Sudden Like It From The Tube Changes. I Have Been Able To Sometimes Get A Little Something Somewhere I Liked By Swapping Tubes But In he Majority Of Instances (For Me) It Wasn't Ever A Massive Difference. I Would Say A Few % At Best. I Will Also Admit I Am Primarily On The High Gain Side Of The Tonal Spectrum. In My Experience I Find Being On The Crunch And Definitely The Cleaner Side Sonically I Was Able To Tell More Differences In Rolling Tubes In All Positions. For The Brutals, Most Of The Time It Is V1, Bias The Power Tubes In The Proper Range And Chug. :) YMMV
 
p.s. I did a little messing around with that when I had my V25. I loved that amp when I first got it and "really liked it" when I sold it. I thought it was really close, but lacked the "weight" that comes with bigger glass/iron. I was still going to keep it as my "versatile small amp head" but after getting the Archon I just couldn't justify it. Then I sold it and the guy I sold it to said "I thought you said the tubes were good. I put new power tubes in it and it sounds MUCH better now! Sadly, I had already purchased new Mesa power tubes, but when I decided to sell it didn't put them in. Who knows if it really had "lost" something and maybe I would have kept it if I heard it with new tubes.
I forget - you have a 50 watt US Archon head? I’m thinking I’ll eventually get something with a good clean channel that goes from crystal clean to a bit past EOB, and a good dirt channel that goes from “some” to “Lots” of dirt, with bonus points for coping something close to 70’s and 80’s Marshall, and more bonus points for going to way over the the top levels of gain. That’s kinda what the little Mesa does, but it’s kind of a PIA to dial in.
 
Maybe Your Mark Amps Are Different Than Mine? If I Want Them To Sound Different I Can Turn My Amp Controls Clockwise AND Counter Clockwise And Get Different Sounds. Those Slider Thingies Do Something Too! I Am Not Sure What Though. I Think They Might Could Help. I Haven't Tried Them. ;)

Kidding...

Tube Rolling (In My Experience) Can Be Helpful If You Have A Stash Of Tubes At Your Disposal And Time To Spend. The Problem Is Ear Fatigue And Being Able To Genuinely Remember What The Sound Differences Were (If Any). I Have Made Some Changes That Were Positive When Played Loud Or Quiet And Vice Versa. If A Person Doesn't Have A Tube Stash (Especially With Today's Prices) I Would Refrain From Messing Around Much With Them And Experiment When It Comes Time To Replace Tubes. On Amps That Bias Can Be Adjusted, I Would Always Start There And See What The Amp Is Biased At First. Often Times, They Are Biased Cold And Getting Them In Proper Range Can Make A Huge Difference As Well. I Have Never Been Able To Change Tubes (Power or Pre) On An Amp I Didn't Like And All Of A Sudden Like It From The Tube Changes. I Have Been Able To Sometimes Get A Little Something Somewhere I Liked By Swapping Tubes But In he Majority Of Instances (For Me) It Wasn't Ever A Massive Difference. I Would Say A Few % At Best. I Will Also Admit I Am Primarily On The High Gain Side Of The Tonal Spectrum. In My Experience I Find Being On The Crunch And Definitely The Cleaner Side Sonically I Was Able To Tell More Differences In Rolling Tubes In All Positions. For The Brutals, Most Of The Time It Is V1, Bias The Power Tubes In The Proper Range And Chug. :) YMMV
I can not disagree with word you’ve said. My goals are 1) to make the little Mesa a little more towards crunch, and less chug, and 2) to play quietly a little easier, so maybe I can forego the power station. Definite maybe on 1, pretty much no joy on 2. Regarding 1, your teasing about knob turning is pretty much on point. I don’t think tube juggling accomplished anything more than knob turning. I’ll leave it alone for a bit, then switch back.
 
I can not disagree with word you’ve said. My goals are 1) to make the little Mesa a little more towards crunch, and less chug, and 2) to play quietly a little easier, so maybe I can forego the power station. Definite maybe on 1, pretty much no joy on 2. Regarding 1, your teasing about knob turning is pretty much on point. I don’t think tube juggling accomplished anything more than knob turning. I’ll leave it alone for a bit, then switch back.
I Hope I Am Wrong Here With What I Am About To Say But Experience Is Causing Me To Say It In Hopes It May Help You. Nothing Is Easy About Marks And Getting Vastly Different Tones Quickly Unless You really Have A Ton Of Time On The Amp And Most Of Us Don't Have That Kind Of Time (Experience) With One Amp. The Controls Work In Odd Ways At Times And Interact With Other Controls As You Most Likely Know. When You Add Or Subtract Volume, Everything Changes Again And A Lot Of Settings We May Gravitate To (Visually) On Other Amps Simply Will Not Work On Mesa Mark Series Amps. I Hope You Can Get What You Want From The Amp. When You Go From Quiet To Loud All The Settings Will Likely Be Off And You Will Have To Start Tweaking Again At That Volume To Get It To Your Liking. There Are Awesome Ones In There For Sure! Finding Them Is Often Times More Time Consuming And Frustrating That We Are Used To Our Wanting Them To Be.

You Mentioned The Archon. I Own The US 50 And 100 And Have Nothing But Praise For Them. Great Amps! If You Want Simplicity, Versatility And Quality Tones From Clean To Crunch To High Gain, It Is A Tough Amp To Beat For An All In One Option.
 
I Hope I Am Wrong Here With What I Am About To Say But Experience Is Causing Me To Say It In Hopes It May Help You. Nothing Is Easy About Marks And Getting Vastly Different Tones Quickly Unless You really Have A Ton Of Time On The Amp And Most Of Us Don't Have That Kind Of Time (Experience) With One Amp. The Controls Work In Odd Ways At Times And Interact With Other Controls As You Most Likely Know. When You Add Or Subtract Volume, Everything Changes Again And A Lot Of Settings We May Gravitate To (Visually) On Other Amps Simply Will Not Work On Mesa Mark Series Amps. I Hope You Can Get What You Want From The Amp. When You Go From Quiet To Loud All The Settings Will Likely Be Off And You Will Have To Start Tweaking Again At That Volume To Get It To Your Liking. There Are Awesome Ones In There For Sure! Finding Them Is Often Times More Time Consuming And Frustrating That We Are Used To Our Wanting Them To Be.

You Mentioned The Archon. I Own The US 50 And 100 And Have Nothing But Praise For Them. Great Amps! If You Want Simplicity, Versatility And Quality Tones From Clean To Crunch To High Gain, It Is A Tough Amp To Beat For An All In One Option.
Yeah, that’s kind of been my experience with the little mark as well. It seems to not be an isolated sentiment. I’ll have to keep my eyes peeled for a good deal on an Archon one day. They seem to be a good option, and not as popular. Mean time, the little mark is doing a fine, if occasionally tedious job.
 
I’ve had a lot of Boogies, though not the one you have. Good tubes help them shine. It’s really hard to tell the effect a tube (or pair, etc) has if you change more than one at a time.

The Mesa SPA12AX7 is a screened tube, as you mention, but doesn’t sound different from their normal 12AX7… still, I always put one into V1 just because that location multiplies the problems a microphonic tube can cause. It’s a solid move.

The 12AT7 is a lower output tube often used to tame overly aggressive amps where a channel or gain stage has less usable headroom than needed, or the specific use doesn’t require as much power. It’s about 40% (roughly, you know how tubes are) lower powered than the 12AX7. Personally, I’ve never liked the effect of replacing a 12AX7 with a 12AT7. The effect always seems weak, but then another player who plays a lot of clean styles or uses only pedals for distortion tones might really dig it. It’s all in the use. You’ll often find the 12AT7 in other tube slots though, like a reverb driver, etc.

You could even go all the way down to a 12AU7, but I can’t image that ever being useful or needed. But it is a direct swap, like the AT, and has much less power than even the AT has.

In my experience, a good V1 and some nice power tubes have gained the most ground for me. With the fixed bias, it‘ll be a bit of a crap shoot if you get NOS power tubes, but most places like The Tube Store or Watford Valves (depending on your side of the Atlantic) can match the Mesa standards. Old or worn power tubes sound dull and a bit 2D, so a fresh set can open an amp up like new strings on a guitar. Good luck!
 
If you can swing NOS, an RCA or GE 12AX7 in V1 is pretty darn nice.

As Rick says, the Mesa SPA tubes are simply selected and heat-shrink-wrapped standard tubes. They don't sound different. However, I find they work well and last a long time in the Phase Inverter position.

However, they're simply rebranded Chinese current production tubes.

What transformed both my Lone Star and Fillmore from 'very good' to 'great' amps I'd probably never sell was putting US and European NOS in all the preamp tube positions.

In the Lone Star I have NOS RCA in v1, NOS GE in v2-4, and an NOS Siemens in v5. The amp became a keeper when I did that.

In the Fillmore, I have all NOS GE preamp tubes.

The HXDA and DG30 are 100% NOS including power tubes.

In both amps I have Telefunken-branded 6L6s that are cryo-treated (yeah I know, tweaky, but it's an industrial process designed to stiffen metal, and you don't get tube rattle. They also sound very good, close to NOS for a fraction of the price. They're made by JJ and hand picked before the cryo treatment.

Telefunken (the resurrected company) makes very high end microphones that sound absolutely great - their main business isn't tubes.

Here's what I've found over the years with NOS: It's not that the amps sound OMG night and day different - it's more subtle than that; it's that they are way more satisfying in the long term. The depth of their tone is just...I dunno...what you hoped for when you bought the amp. Satisfying. The amp goes from a "should I keep this or try something else" to a keeper.
 
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