Dennis Had Inspire Amps

[FloridaBoy]

Got it.

[x3workshop]

Originally Posted by Analog Addict

The 6L6 is a wonderful sounding tube in it's many configurations. My particular favorites are the 6L6G, 6L6GA, and the 6L6GAY. Of the 6L6GC versions, I like the GEs the best. The guitar amp guys tend to gravitate towards the RCA 6L6GC black plates, which command premium prices. So much so, I couldn't resist liquidating a quad last week. But to my surprise, they went to an audio guy. I have a lot of 6L6WGBs, 5881s, etc, but the gem of my 6L6 stash is a NOS quad of WWII vintage Sylvania JAN 6L6GAs with the U.S. anchor printed on the base. I'm saving them for when I build a PSE beam tetrode amp....

Guilty as charged! I'm running an octet of RCA blackplates in a pair of monoblocked MC240s driving Martin Logan ESL's and they are awesome sounding! C100A preamp, all digital sources.

I like the GE's as well, but I'll admit to a BP fetish in this setup. GE's sound better in my MC30's.

[timeout59]

How do I tell if my amp is "triode-strapped"? It's one of the higher output versions but I don't think it has the 20 watt trannies I've seen mentioned.

I've used:

JJ KT88s with a variety of NOS 6SN7s, JJ GZ34

Pope 6V6GTs with Psvane CV-181-T II, RCA 5U4G or a British CV1863 / 5Z4GY

Both combinations sound great to me, slightly different.

[Bombadil]

I believe all of the Inspire amps are single ended pentode, unless you specifically order a triode configuration. If it is triode-configured then it will produce about half the power of a pentode amp. Thus an Inspire SE KT88 HO advertised as producing 12 watts per channel with KT88 tubes, is a pentode. If it were triode, then maximum output would be 6 watts per channel.

Some amps come with a switch, enabling the user to switch between triode and pentode (or ultralinear). I've never seen an Inspire amp with this option.

[Bombadil]

When using a 2.0V source component and an amp with a 1.5V input sensitivity, it can be problematic to use a passive preamp. This would require one to turn the volume level on the passive pretty high. And if a CD's or LP's recording level is on the low side, it is possible that even with the passive turned to maximum, the amp will not reach full power. If one were going to use a passive with an Inspire, I'd want the Inspire's input sensitivity set to 1.0V.

My Inspire SE EL84 amp's sensitivity feels like it is closer to 2.5V than 1.5V. I have to jack my active preamp's to fairly high volume level settings to get much output. And I can't get to full output with my passive.

There's also a matter of matching impedances. Which usually isn't a problem with tube amps, as they have high input impedances.

Cabling can be an issue with a passive too, as an interconnect with high capacitance and longer length, can roll off high frequencies.

[timeout59]

Mine is single ended pentode then.

[FloridaBoy]

[QUOTE=Bombadil;844250]I believe all of the Inspire amps are single ended pentode, unless you specifically order a triode configuration. If it is triode-configured then it will produce about half the power of a pentode amp. Thus an Inspire SE KT88 HO advertised as producing 12 watts per channel with KT88 tubes, is a pentode. If it were triode, then maximum output would be 6 watts per channel.

Some amps come with a switch, enabling the user to switch between triode and pentode (or ultralinear). I've never seen an Inspire amp with this option.QUOTE] I've seen one and it appeared to be an early one.

MA, Twanny and I have triode strapped amps built on the 45 chassis with 20 watt transformers. 8-10 watts with KT 88's depending on the rectifier used. 5-7 watts with a 6L6. Plenty for my on paper 99db speakers.

Dennis said that I had to get this amp he was just finishing up...so I did.

[FloridaBoy]

Originally Posted by timeout59

How do I tell if my amp is "triode-strapped"? It's one of the higher output versions but I don't think it has the 20 watt trannies I've seen mentioned.

I've used:

JJ KT88s with a variety of NOS 6SN7s, JJ GZ34

Pope 6V6GTs with Psvane CV-181-T II, RCA 5U4G or a British CV1863 / 5Z4GY

Both combinations sound great to me, slightly different.

Have you tried the Pope's with a 5Y3/80 rectifier? Lower power but very sweet. You can use any rectifier with them. Kevin Deal ran them with 450 volts on the plates. No issues.

[FloridaBoy]

Originally Posted by Analog Addict

The 6L6 is a wonderful sounding tube in it's many configurations. My particular favorites are the 6L6G, 6L6GA, and the 6L6GAY. Of the 6L6GC versions, I like the GEs the best. The guitar amp guys tend to gravitate towards the RCA 6L6GC black plates, which command premium prices. So much so, I couldn't resist liquidating a quad last week. But to my surprise, they went to an audio guy. I have a lot of 6L6WGBs, 5881s, etc, but the gem of my 6L6 stash is a NOS quad of WWII vintage Sylvania JAN 6L6GAs with the U.S. anchor printed on the base. I'm saving them for when I build a PSE beam tetrode amp....

The Shuguang KT66z is an excellent tube too. *I* prefer it to the new TS 6L6G. AA what is the other forum you post on?

[timeout59]

"Have you tried the Pope's with a 5Y3/80 rectifier? Lower power but very sweet. You can use any rectifier with them. Kevin Deal ran them with 450 volts on the plates. No issues."


I haven't tried the Pope 6V6GT with an 80 rectifier but will. Didn't know an 80 was even a possibility in the amp.