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Rolling power amp input valves - worth it?

Thetiminator

Painfully virile
Hi everyone

I’m new to valve amplifiers having just got myself a pair of Transcendent Sound Pinnacle OTL amps - which are truly superb by the way. A dealer friend of mine sent me a very expensive Kondo 300B amplifier to test but the Pinnacles spanked the Kondo’s bottom in every area.

Anyhoo, there are 2 x JJ 803’s and one JJ802’s in each amp driving 4 x EH Gold Grid 300B’s. Question is how much do they input valves contribute to the sound and would it be worth trying a couple of different brands?
 
I’ve found that changing the driver or line stage valves make more of a difference than the power ones.

Give Genalex gold lions a try, I’ve been very impressed with them recently and they are quite cheap.
 
On my mcintosh the pre tubes mad quite a change, the drivers a bit (stil worth it). On my Radford STA it's all in the driver tube (EL34), and unfortunatly i like the telefunken best.
On my Rogue cronus tube amp it was a mixture. Smal tubes did a difference, but with Siemens EL34 it was fantastic ( it's a bargen amp if you ask me )
 
As you're new to valves and have just acquired a really nice pair of amplifiers I'd get some serious listening time in first before you start tube rolling etc. It can take several months or more to become fully acquainted with new kit.
 
Thanks guys. I wasn’t sure how much they attributed to the SQ in a power amp. I had a valve head amp where they did make a large difference. I’ll let the amps settle a bit too as they probably only have c.50 hours on them and then have a play.
 
JJ are bog standard tubes ( like many EH ) , most of which are reliable yet unengaging . Often found in cheap guitar amps .
Go on Tubedepot and The Tube Store and check around for alternatives .
On the power tube front , differences are less , but noticeable nevertheless . Re-issue Western Electric are instantly way better than EH .
The prices you can pay for a quad of many 300B can be quite high though .
 
They should be taking preorders for the new WE 300b in a few weeks, prices don't seem to be massively horrendous.
 
Including VAT I'd say around £1200 per matched pair.
 
Are these the single ended amps or push pull?

Recently took delivery of the Pinnacle kit, I’m going to build mine with some mods.
 
Are these the single ended amps or push pull?

Recently took delivery of the Pinnacle kit, I’m going to build mine with some mods.

The SE Pinnacles. Just had mine built by David Coe, they are superb. Better, or certainly no worse, than a £40k Kondo I had here.

David did a few mods but nothing really major...some caps and had to uprate some fuses. There were some missing diodes and screws missing in the kit but no biggie.
The earth was a bit of a problem but sorted as best we could. Fine on 96db Tannoys but very noticeable on my 106db horns.

Only other thing is the plastic front cover for the amps, it seems like the screw holes are a mil or 2 too close together so the panel bows out a bit...
 
Have heard a highly modded SE pair, best sound I’ve ever heard from an amp. Shame the SE is no longer available. At least the PP gives you a wider choice of speakers
 
My tuppence worth. In my Audiopax 88s, The 12 AT7s can alter the sound dramatically, the KT 88s, not so much. Strangely it seems hard on the driver valves but the power valves last for ages?
 
The SE Pinnacles. Just had mine built by David Coe, they are superb. Better, or certainly no worse, than a £40k Kondo I had here.

David did a few mods but nothing really major...some caps and had to uprate some fuses. There were some missing diodes and screws missing in the kit but no biggie.
The earth was a bit of a problem but sorted as best we could. Fine on 96db Tannoys but very noticeable on my 106db horns.

Only other thing is the plastic front cover for the amps, it seems like the screw holes are a mil or 2 too close together so the panel bows out a bit...

You can see the story of the build here https://adaudioconsultants.wordpress.com/2018/11/14/transcendent-audio-the-pinnacle-2/
 


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