Dennis Had Inspire Amps

[decooney]

Originally Posted by straitwire

That is the first production PSE with gas regulation.
It uses three VR75/0A3's as regulators.
I have been listening to my proto with metal 6L6's and 6F6's...

Are there any notable differences with the sound of these earlier version PSE amps?

[FloridaBoy]

Originally Posted by decooney

Are there any notable differences with the sound of these earlier version PSE amps?

I believe the gas regulators beef up the power supply and the amp sounds more powerful. I could be wrong.

[Analog Addict]

The voltage regulator tubes have at least a couple of benefits. Of course, they regulate the voltage, but in doing so, help to eliminate a subtle form of distortion that occurs without voltage regulation. In addition, the VR tubes are quieter than Zener diodes, decreasing the background noise. There are probably other reasons as well, but I remember Dennis specifically talking about these

[straitwire]

I watched an interesting video on you tube titled...zener diode vs tube regulation and more, it's a long video but if you start watching at 26 minutes 52 seconds you see two comparisons of zener vs tube...stability and temperature coefficient...but honestly, I like them because they are so cool looking, but as it turns out they are also slightly better than zeners in some ways...which is nice too

[Tyson]

Just switched from Westinghouse 6SN7GTB, RCA 6L6GC grey glass and CBS Hytron 5Y3GT to the Psvane CV-181 grey glass, Gold Lion KT66 and Gold Lion GZ34 tubes.

Well even not burned in the newer tubes are a lot more forward and punchier than the prior tubes. We'll see how things play out over the next week or 2 after burn in.

[Tyson]

Also, to the Psvane tubes "really" take 300 hours to burn in like I've heard some people claim?

[Bombadil]

Switching from a 5Y3GT to a GZ34 should make for a punchier / more powerful sound on its own. That is a big increase in current to the output tubes, along with a lot less sag / voltage drop. The 5Y3GT is about the weakest rectifier you can run.

[Tyson]

I also found some nice Holland made Mullard EL34 tubes with DD getters and some original Tung Sol 6550 (USA made) tubes. Man, so many tubes to try out!!

With some of the "premium" new tubes like Psvane, Emission Labs, Elrog, etc being so expensive, it just makes sense to buy NOS when possible. Of course I have a bunch of Electro-Harmonix and new production Tung Sol and new production Mullard, Sovtek, etc... but it's so much easier to justify a little more $$ for NOS when it's just a pair of output tubes needed. My old amps took a quad (or more), so I was way more price sensitive before.

Although $230 for a pair of NOS Tung Sol 6550s (branded Sylvania) is about the upper limit of what I'm willing to pay. Although, at the rate I swap tubes, theoretically the various tubes I have might actually last me the rest of my life :P

[FloridaBoy]

Originally Posted by Tyson

I also found some nice Holland made Mullard EL34 tubes with DD getters and some original Tung Sol 6550 (USA made) tubes. Man, so many tubes to try out!!

With some of the "premium" new tubes like Psvane, Emission Labs, Elrog, etc being so expensive, it just makes sense to buy NOS when possible. Of course I have a bunch of Electro-Harmonix and new production Tung Sol and new production Mullard, Sovtek, etc... but it's so much easier to justify a little more $$ for NOS when it's just a pair of output tubes needed. My old amps took a quad (or more), so I was way more price sensitive before.

Although $230 for a pair of NOS Tung Sol 6550s (branded Sylvania) is about the upper limit of what I'm willing to pay. Although, at the rate I swap tubes, theoretically the various tubes I have might actually last me the rest of my life :P

FWIW, I have found that most of the new production power tubes better sounding than old production. There are some exceptions. YMMV.

The Shuguang and Psvane CV-181's do take some hours to settle in.

[Tyson]

Originally Posted by FloridaBoy

FWIW, I have found that most of the new production power tubes better sounding than old production. There are some exceptions. YMMV.

The Shuguang and Psvane CV-181's do take some hours to settle in.

I do have Gold Lion KT88s, Black Treasure KT88s, Penta Labs KT88s and Sovtek KT88s that it'll be fun to compare the NOS Tung Sol 6550s to.

The Gold Lion KT77s that everyone seems to love I just can't agree. I've listened to it a fair bit in a few different amps now, and to me its always a bit hard/flat sounding vs other tubes. Even the Gold Lion KT66 sounds better to me. Although the Shuguang KT88 Black Treasure is probably my favorite modern pentode/tetrode tube so far.