NOS pre´s

[bentium]

i used one at V1 in my DC5 for a few months, and i liked it. I had slightly more hiss in my sound, but overal sound was more creamy and mellow, what i liked

 

[merendina]

IMHO tele's 12ax7 are too much "Hi Fi" for a guitar amplifier.

If you like smooth sound old mullard can to be your coice. But try also 12ax7 amperex/philips or rca..

These are the best for the mark series IMO

 

[phyrexia]

just got to watch yourself with combos. I killed a couple nice tubes in my Mark III. Maybe they were bad tubes or maybe it was because my speaker was 1/4" from some of the tubes.

 

[edward]

I use a NOS Mullard ax7 in the V1 of my DC5 combo. No issue whatever. Moreover, it nipped out the brittle highs, smoothing both the Lead and Clean channels' top end a bit. A definite worthwhile change. OTOH, it didn't seem to make much of a diff in my MKIII's V1 though, ...go figure

Edward

 

[MrMarkIII]

All 12AX7s have the same basic gain, although some claim to sell "high-gain kits".
It may be better to use "short-plate" tubes in combo amps to avoid microphonics.
The older tubes, like Mullards, were made with better materials and QC, which is why they command high prices.

 

[phyrexia]

All 12AX7s have the same basic gain, although some claim to sell "high-gain kits".
It may be better to use "short-plate" tubes in combo amps to avoid microphonics.
The older tubes, like Mullards, were made with better materials and QC, which is why they command high prices.

Not all current 12AX7s have the same gain. They are generally 15 to 20% less gain than what the 12AX7 spec calls for. NOS tubes are usually full gain with regard to the 12ax7 spec.

 

[stokes]

just got to watch yourself with combos. I killed a couple nice tubes in my Mark III. Maybe they were bad tubes or maybe it was because my speaker was 1/4" from some of the tubes.

That combo paranoia is just that,tubes,especially NOS tubes were made tough as nails.The military depended on them back in the day for use in things like radios in a B-17.Do you really think the speaker in your combo can give it more punishment than a B-17 flying thru a field of flak? Current production tubes may fall to the vibration an amp kicks,they are built like crap compared to the old ones.I have an Ampeg combo that has the same preamp tubes from the '60's,and throughout the '70's and the early eighties the amp was used by my bass player,cant shake a combo any harder than that,those Bugle Boys are still going strong.As a matter of fact,I have never seen a tube die a premature death because of using it in a combo.

 

[phyrexia]

That combo paranoia is just that,tubes,especially NOS tubes were made tough as nails.The military depended on them back in the day for use in things like radios in a B-17.Do you really think the speaker in your combo can give it more punishment than a B-17 flying thru a field of flak? Current production tubes may fall to the vibration an amp kicks,they are built like crap compared to the old ones.I have an Ampeg combo that has the same preamp tubes from the '60's,and throughout the '70's and the early eighties the amp was used by my bass player,cant shake a combo any harder than that,those Bugle Boys are still going strong.As a matter of fact,I have never seen a tube die a premature death because of using it in a combo.

Well, I know that, but I've blown more "NOS" tubes than real ones. I've killed a GE, a Mullard, and a JAN Philips 5751, all in different positions, and all when I had the amp up to about halfway on the master (read: l-l-loud). The only new tube I've had go bad on me was a Ruby that went dead within 15 minutes of use.