Mark VII's Tubes - Not Too Shabby!

[László]

When I ordered the Mark VII I figured that the first order of business would be to install NOS tubes. It's what circumstances usually compel me to do.

However, I'm liking how the amp sounds with the stock tubes, and at least for now, I'm going to wait to decide whether the expense of NOS will be necessary. There's excellent clarity and surprisingly good tonal balance that I'm hearing from this amp, without the 'zing' and ring of what Mesa used to install in the amps I got previously. They're a little brighter than my usual NOS, but not unacceptably so.

I'm confident the tubes they're currently installing are JJs.

They have high build quality. The parts and wiring appear to be properly installed and upright; there are vintage style fingers on the Mica spacers to reduce tube rattle; the same upper-bottle inner shaping on the preamp tubes, and high quality in the output tubes. Comparing them side by side with JJs, they appear the same.

Seems Mesa made a good choice here. I can put the money for NOS into other things I need. I've felt that JJs were the closest to NOS I've found so far, and that conclusion's holding up pretty well.

 

[texhex]

Ain’t nothin wrong with Mesa tubes. Rolled a bunch and landed on the Mesas more than once. They are high quality JJs.

 

[EOengineer]

I’m not sure Mesa is using JJ power tubes anymore. Ive had outstanding results with JJ 6L6s in my Mark III though. I’ll likely be retubing a simul 2:90 with them soon.

 

[László]

Glad I'm not the only one who thinks they're very good!

 

[paisleywookiee]

I'm confident the tubes they're currently installing are JJs.

Nope. PS Vane, unless you got a weird one. The only amps using JJ’s are Cali Tweed 6V6’s, as far as I know.

 

[László]

Nope. PS Vane, unless you got a weird one. The only amps using JJ’s are Cali Tweed 6V6’s, as far as I know.

Maybe I have a weird one! The output tubes are 100% the JJs.

I think the preamp tubes are, too. But I can check one more time. I've been known to be wrong occasionally - last time was in the Pleistocene.!

However the important point is that whatever these tubes are, they sound very good in the amp.

 

[paisleywookiee]

Maybe I have a weird one! The output tubes are 100% the JJs.

I think the preamp tubes are, too. But I can check one more time. I've been known to be wrong occasionally - last time was in the Pleistocene.!

However the important point is that whatever these tubes are, they sound very good in the amp.

Interesting. They may have switched again.

 

[László]

Interesting. They may have switched again.

Beats me. The preamp tubes look like the ones in the Mesa pic, and appear to be what they're putting into all their amps, and are also what the retailers like Sweetwater and others have pictured on their websites.

In the pics below they're shown at a different angle but are exactly the same as the JJs. The Psvanes are in the ones next to their box; you can see that the getter superstructure is different, the plates are a bit longer, and the mica spacer on the JJ doesn't have holes like the Psvane.

The question is whether the Mesa pic is out of date (it does mention their V-Twin pedal, but also has the CA warning and I'm guessing they simply used the old paragraph to describe the tubes).

It's also possible I didn't look carefully enough and have no idea what I'm talking about!

Or, it might be a situation like the old Fender factory; they'd put in whatever they had on hand that day, RCA, GE, Raytheon...didn't much matter to them, they weren't sniffing corks like I do!

 

[paisleywookiee]

Beats me. The preamp tubes look like the ones in the Mesa pic, and appear to be what they're putting into all their amps, and are also what the retailers like Sweetwater and others have pictured on their websites.

In the pics below they're shown at a different angle but are exactly the same as the JJs. The Psvanes are in the ones next to their box; you can see that the getter superstructure is different, the plates are a bit longer, and the mica spacer on the JJ doesn't have holes like the Psvane.

The question is whether the Mesa pic is out of date (it does mention their V-Twin pedal, but also has the CA warning and I'm guessing they simply used the old paragraph to describe the tubes).

It's also possible I didn't look carefully enough and have no idea what I'm talking about!

Or, it might be a situation like the old Fender factory; they'd put in whatever they had on hand that day, RCA, GE, Raytheon...didn't much matter to them, they weren't sniffing corks like I do!

my buddy's shop has a bunch of amps coming in soon. So it'll be interesting to see what they'll have. We were told earlier this year by Mesa "oh yeah, PS Vane is what we're using mostly, going forward". But who knows. Tubes are weird.

 

[László]

my buddy's shop has a bunch of amps coming in soon. So it'll be interesting to see what they'll have. We were told earlier this year by Mesa "oh yeah, PS Vane is what we're using mostly, going forward". But who knows. Tubes are weird.

For all I know you're 100 percent right! I could have missed something in my cursory look.

The Psvane is supposed to be a very good tube, however, according to the audiophile community. So I'm not sure it really matters all that much.

The only Psvane 6L6s I've seen anywhere are their 5881s (6L6 GB). The Mesa 6L6s are 6L6 GC, which isn't the same thing. The ones I have I think are the STR 445s; those are identical to the JJs, and to the Telefunken branded 6L6GCs (select JJs) I installed in my Fillmore 50; the Telefunkens are cryogenically-treated, which sounds like snake oil, but was actually developed at a local university (Wayne State University in Detroit) to stiffen metals for the auto and other industries, and seems to help with tube rattle - it appears to change the molecular structure of the metals in some way that I don't remember, but a set of Telefunkens did stop the annoying rattle in my combo Lone Star. I did switch to NOS EL34s in that amp, and they don't rattle, even though they aren't cryogenically treated.

 

[paisleywookiee]

The Psvane is supposed to be a very good tube, however, according to the audiophile community. So I'm not sure it really matters all that much.

They are good, but you're also right; it doesn't matter too much, as long as the tube is quality, not microphonic, etc.

I'm definitely checking all the amps tonight though, for fun.

 

[laxu]

I still declare the JJ ECC83S is the worst sounding production preamp tube on the market. JJ ECC803S and ECC83MG are far better.

 

[metropolis_4]

I still declare the JJ ECC83S is the worst sounding production preamp tube on the market. JJ ECC803S and ECC83MG are far better.

I tried a set of ECC803Ss in my AC30 on your recommendation and I’ve been very happy with them!

Agreed on the ECC83S. I hate that tube

 

[EOengineer]

I’ll fight anyone that the jj803 might be the best V1 modern production 12ax7. Been using them for years over the 83s and it’s not a small difference. I should note I have a healthy pile of NOS 12ax7s to compare against.

 

[László]

I’ll fight anyone that the jj803 might be the best V1 modern production 12ax7.

No need to fight, I agree with you!