Dennis Had Inspire Amps

[oldominion]

I got a NOS RCA 6bx7 today from seller lowtechelec on Etsy and it's really cleaned up a lot of the hum, interestingly. I guess it makes sense, as the lowest mu (gain) of the 6sn7/6sl7 family.

All of my troubles started when my 6bx7 started going south and I began swapping in 6sn7/6sl7 into the buffer position. Anyhow, glad to be back to somewhat normal!

I'm intrigued by Dennis's 45 amp. I've got a Waamamp 2a3/45 that's been my only real introduction to the 45 tube. I borrowed a pair of Emission Mesh GLobe 45's that do sound wonderful, just not a grand wonderful.

Last, has anyone rolled any 6bl7's into the buffer stage of their 3.1 preamp?

[pechelman]

Been radio silent for the past few days, sorry to leave anyone hanging as I truly appreciate everyone's willingness to help me fix the problems. Dennis also did reach out with an offer for me to return the preamp for a checkout.

In the end, I got connected with someone locally who is also in the tube amplifier business who offered to take a look for me. Figured it couldnt hurt and would save everyone a lot of time and shipping costs. Anyway, he poked around a bit and was able to reduce the 60 and 120hz noise pretty substantially. The preamp is now hooked back up in the 45 Firebottle chain and it sounds great as before, with the same DNA that Dennis put in there, but now without any audible hum or buzz at my listening position. Have to be within an inch of the speaker to hear anything. It's wonderfully quiet, alive, and dynamic. Separation and staging are still fantastic. The resolution seems highly improved from the extra black background.

Did a quick overlay of the before and after from the measurements this person. It's a little hard to see, but the after is the slightly more faint line. The 60Hz peak went from -71db to -92db. With the previous noise floor, this was giving me about 3mV DC at my speaker terminals. Now it's around .2mV.

If I was happy before with Dennis' preamp + amp combo I'm not sure what I am now. Very happy?

[bwilson51]

What did he do to the preamp

[pechelman]

The grounding methodology was reworked to be a bit more conventional. There was also a good bit of noise getting into the signal from the AC heater wires. Dennis packs a lot of goodies into his nice compact chassis, but it got a little close to the selection knob.

[straitwire]

I leave my preamps on more than my amps.
The sound is better when the preamp is warmed up(hot power transformer), and to my ears it seems to make more of a difference than a warmed up amp.
But I don't leave my preamps on 24/7 like I used to.
And you should always turn your preamp on before you turn on your amp or you'll hear the tubes coming up.

[Jprod]

Hello. New to forum. Just ordered one of Dennis’ kt88 sep Amps. I never had a tube amp before. System now is vpi prime turntable , ps audio stellar phono pre, wyred4sound stpse preamp parasound a21 amp and soon to get spatial Audio x5 speakers. I can’t wait to try it in my system. Had my parasound now for 5 years and looking forward to what I hope will be a step up in sound!

[straitwire]

Hey Jprod, welcome to the club!
If you have any tube amp questions just ask, these guys are very knowledgeable and always happy to help a fellow Inspire owner...straitwire...

[Jprod]

Thank you sir. I do have a general question - how do I sneak in a tube amp past the wife without her noticing ?��

[decooney]

Originally Posted by Jprod

Hello. New to forum. Just ordered one of Dennis’ kt88 sep Amps. I never had a tube amp before. System now is vpi prime turntable , ps audio stellar phono pre, wyred4sound stpse preamp parasound a21 amp and soon to get spatial Audio x5 speakers. I can’t wait to try it in my system. Had my parasound now for 5 years and looking forward to what I hope will be a step up in sound!

Should be fun to try with the X5s. I ran a similar type of speaker config. A midrange-woofer and AMT configuration + lower stereo subs similar to X5 - with my Inspire. Your X5s have even better efficiency at 97db. Compared to your A21 you should hear more depth and dimension, and nice midrange with the AMT section. Congrats!

[Masterlu]

Originally Posted by Jprod

Thank you sir. I do have a general question - how do I sneak in a tube amp past the wife without her noticing ?��

Just tell her;

“I really can’t believe how long it took for this to get repaired; I’m just glad to finally get it back in my system.”