Dennis Had Inspire Amps

[pstrisik]

Originally Posted by timeout59

I'd like to try some Tung-Sol NOS 6AR6 tubes in my Inspire. Back in posts #894 and #898 they were reported as sounding fantastic. What kind of adapter do I need?

timeout... I've got the adapters and tubes if you want to contact me. you can PM me at Audiocircle - same screen name.

[Bombadil]

I've read good things about the 6AR6 tube, with a caveat. Many amps need to be modified to run them, as they do not like more than 300V on their screens. Many 6L6 and EL34 amps run hotter than this. I have no idea what the Inspire amps are spec'ed at on the screens. It is said that the 6AR6 lifespan will be short if run at 350V or higher. They also are said to sound their best with a screen voltage of 275V to 300V. So it may need more than a tube adapter.

Same is true for the Bendix 6384 tubes, which don't like more than 325V on their screens.

By comparison, a KT88 can handle up to 600V.

[pstrisik]

Originally Posted by Bombadil

I've read good things about the 6AR6 tube, with a caveat. Many amps need to be modified to run them, as they do not like more than 300V on their screens. Many 6L6 and EL34 amps run hotter than this. I have no idea what the Inspire amps are spec'ed at on the screens. It is said that the 6AR6 lifespan will be short if run at 350V or higher. They also are said to sound their best with a screen voltage of 275V to 300V. So it may need more than a tube adapter.

Back when we were trying them (I think Florida Boy introduced them here), Dennis thought they were fine to run in the SEP amps. He even designed an amp around the tube. (edit: here it is along with his comments..... https://www.audioaficionado.org/show...081#post718081)

I remember being very impressed with them. But memory fades. Keep trying new tubes, on and on... . There are many combos that are great, though different from each other.

[Bombadil]

Reads to me like he had to make design changes to his standard amp in order to use 6AR6 or 6384 tubes. His quote, "Oh, I might mention ...
the 6AR6 and especially the 6384 ain't no 6L6 sub ... the sonic merits along
with the plate impedance in the triode mode is completely different along
with the sonic merits." says to me that there were significant differences.

It would surprise me if SEP amps designed to use a KT88 as their optimal tube (which many Inspire amps are) would be perfectly optimized to also use a 6AR6. Such very different tubes, which require much more than simply changing the bias. Surely he isn't running the screen voltages on a KT88 amp at just 300V.

From what I've read on the 6AR6, it sounds like an amp optimized to use them might sound very, very good.

Perhaps if one used a much lower output rectifier, like a 5Y3, it could drop voltages down closer to what the 6AR6 likes.

[Analog Addict]

Over at the candy store playing. Now to see if I can get Flickr to work...

[Analog Addict]

https://flic.kr/p/G8XEEn

https://flic.kr/p/215A7QD

[Musica Amantem]

In my Triode-configured KT88 Inspire amp, the 6AR6 (w/adapters) did not sound anywhere near my liking, so I never plugged them again. I may try to have them burn-in for a while and then listen to them again, one of these days.

[david45]

Originally Posted by Analog Addict

Over at the candy store playing. Now to see if I can get Flickr to work...

Please do tell us more!


By the way I could land in Raleigh on Dec. 12th around 2.00 or 3.00 in the afternoon and spend the rest of the day or evening in Cary. Would my visit to the candy store work with your schedule? I have yet to get a full reply from DH but it will come

David (same username on audio circle)

[Analog Addict]

Originally Posted by david45

Please do tell us more!


By the way I could land in Raleigh on Dec. 12th around 2.00 or 3.00 in the afternoon and spend the rest of the day or evening in Cary. Would my visit to the candy store work with your schedule? I have yet to get a full reply from DH but it will come

David (same username on audio circle)

I would be able to attend, and could bring my toys. Of course, I don't hold the keys to the candy store, so stay tuned....

[IMG]Untitled by Analog Addict, on Flickr[/IMG]

Dennis' PSE with 6V6s, A just completed SET(P) with KT-77s, and Tony's SEP with EL34's. We switched Tony's from pentode to strapped triode, and made a big improvement to my ears. Also changed the KT-77s out for KT88s on the middle unit.

Tony's personal LP-3 with one off remote volume control and LED volume knob...

Untitled by Analog Addict, on Flickr

[david45]

Thanks for giving additional information, Allan.

For some reason I was under the impression that Tony's amp was already wired as triode... Memory is a faculty which forgets they say

Hopefully DH can have a similar amp in house for December!

Would you say the mid range 'lusciousness' is getting closer to what you are used to with your personal amp or is it simply a bit of an improvement over the regular PSE design?