Dennis Had Inspire Amps

[Musica Amantem]

At the moment, I slightly prefer the Psvane CV-181 T-II gray coat with the Shu Guang KT-66z. It has slightly better bass control and presence over the black glass CV-181. I'll be testing the KT-77 with the Psvane CV-181 T-II gray coat momentarily hoping it may improve what is already an outstanding sound. Like I said earlier, both CV-181's are great with these Kinkless Tetrodes, their perceived differences probably stemming from taste preferences.

[FloridaBoy]

Originally Posted by Musica Amantem

At the moment, I slightly prefer the Psvane CV-181 T-II gray coat with the Shu Guang KT-66z. It has slightly better bass control and presence over the black glass CV-181. I'll be testing the KT-77 with the Psvane CV-181 T-II gray coat momentarily hoping it may improve what is already an outstanding sound. Like I said earlier, both CV-181's are great with these Kinkless Tetrodes, their perceived differences probably stemming from taste preferences.

System differences too.

Listening to GE 6V6GT's with the black CV-181 and a Pope/Philips 80. Nice!

[FloridaBoy]

Search: 6V6G IEC Mullard (RCA MADE) Matched Pair Vacuum Tube NOS NIB Tested Strong

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[pstrisik]

Here's my weekend update (with apologies to Chevy Chase).... still feels preliminary though.

Two areas: 1- Russian GL KT-77 and 2- 6CG7 drivers in my 6922/6DJ8 based Inspire.

KT-77 -

Let them run in for thirty hours before listening, but still found them slightly harsh on the top compared to the Mullard EL-34 reissue and the =C= EL-34 which, newly tried, is quite nice. I will give them another 30 hours before seriously listening again to see if they mellow any.

6CG7 -

Quite an interesting experiment. I haven't fully decided about them. I've tried the RCA "clear top" 6CG7 and again tried Sylvania "chrome dome" 6SN7 with adapter. Both sound similar in my system. On the one hand, they seem to offer more transparency and depth. Sometimes they seem thin though. When I go back to a 6922 type, the sound is fuller and maybe more natural. It's the kind of difference that I need to sit with for some time to really see how it feels. My guess is that my previous sense that "something was off" may still apply, though not as pronounced with the IIPS mod (which seems to help everything to sound better!).

Meanwhile, I thought it worthwhile to order another example and have a Mazda 6CG7 on the way from Upscale Audio (who has mercifully started to use the USPS so I don't have to pay a fortune for shipping from them any longer).

"That's the news. Goodnight, and have a pleasant tomorrow."

[Musica Amantem]

The jury is still out on the differences between both CV-181's (Shu Guang and Psvane) in relation to the GL KT-77. More testing to come.

Peter, I'm sorry it has not yet worked for you (GL K-77), but I guess my impressions are more related to the Triode configuration, and it is probable that the EL-34 will sound transparent in my case but slightly underwhelming in terms of body of sound and bass. We'll see.

My system's preferences:

Output tubes:

GL KT-77 / Shu Guang KT-66z (tie)
VA 6550 / GL KT-88 (tie)
6P3S-E
VA 350B
Svetlana KT-88
RCA 6V6 G ST black plate
JJ 6V6
Reflektor 6V6 GT
TungSol 6AR6WA w/Adptr

Input tubes:

Psvane CV-181 T-II / Shu Guang CV-181 black glass (tie)
Super-Radiotron 6SN7 GTA
... the rest

Rectifiers:

Sophia Electric (mesh plate) 274B / Westinghouse-labeled Amperex (Holland) 5AR4 (tie, depending on output tube)
Brimar 5Z4
... the rest

Still working on VA's 350B and 6550, and comparing CV-181's with the GL KT-77. Eventually trying Mesa 6550 and some other EL-34 / 6CA7 type. Finally, I'll be trying to replace Caps in both units (no rush though).

[FloridaBoy]

Originally Posted by Musica Amantem

The jury is still out on the differences between both CV-181's (Shu Guang and Psvane) in relation to the GL KT-77. More testing to come.

Peter, I'm sorry it has not yet worked for you (GL K-77), but I guess my impressions are more related to the Triode configuration, and it is probable that the EL-34 will sound transparent in my case but slightly underwhelming in terms of body of sound and bass. We'll see.

My system's preferences:

Output tubes:

GL KT-77 / Shu Guang KT-66z (tie)
VA 6550 / GL KT-88 (tie)
6P3S-E
VA 350B
Svetlana KT-88
RCA 6V6 G ST black plate
JJ 6V6
Reflektor 6V6 GT
TungSol 6AR6WA w/Adptr

Input tubes:

Psvane CV-181 T-II / Shu Guang CV-181 black glass (tie)
Super-Radiotron 6SN7 GTA
... the rest

Rectifiers:

Sophia Electric (mesh plate) 274B / Westinghouse-labeled Amperex (Holland) 5AR4 (tie, depending on output tube)
Brimar 5Z4
... the rest

Still working on VA's 350B and 6550, and comparing CV-181's with the GL KT-77. Eventually trying Mesa 6550 and some other EL-34 / 6CA7 type. Finally, I'll be trying to replace Caps in both units (no rush though).

MA, I put the Penta Labs KT88's with the 274 in and still prefer the 6V6/6L6 GLKT77. Could be my room and speakers of simply personal preference.

Peter, the GL KT77's either need more time or they are simply not for you in your rig.

[Musica Amantem]

Originally Posted by FloridaBoy

MA, I put the Penta Labs KT88's with the 274 in and still prefer the 6V6/6L6 GLKT77. Could be my room and speakers of simply personal preference.

Peter, the GL KT77's either need more time or they are simply not for you in your rig.

I believe KT-88 is a great tube, but not the best in Triode mode. The 6L6 / KT-66 and KT-77 are better fits for that topology, at least in my rig. Big difference between us is the 6V6 alternative. My three 6V6 samples are anemic and lack presence, sounding overall mediocre. It must be system-dependent, but the 6V6 performance in my rig is part of the reason behind my hypothesis of a correlation of max plate current spec range in Triode. In the 6V6 case, it is too low (40+ mA compared to 60+ mA of the 6L6 and more for larger tubes)

[x3workshop]

All of your rolling is very informative, especially your analysis MA. Lots of data for thought.

[Musica Amantem]

Just observation, and a need to narrow the potential upgrade paths. Thanks for the kind words.

[FloridaBoy]

Originally Posted by Musica Amantem

I believe KT-88 is a great tube, but not the best in Triode mode. The 6L6 / KT-66 and KT-77 are better fits for that topology, at least in my rig. Big difference between us is the 6V6 alternative. My three 6V6 samples are anemic and lack presence, sounding overall mediocre. It must be system-dependent, but the 6V6 performance in my rig is part of the reason behind my hypothesis of a correlation of max plate current spec range in Triode. In the 6V6 case, it is too low (40+ mA compared to 60+ mA of the 6L6 and more for larger tubes)

As always, it's trust your ears.