Dennis Had Inspire Amps

[FloridaBoy]

[QUOTE=Musica Amantem;846881]Most likely a mistake.

BTW, I came across a paper from Steve Deckert (Decware) which addresses differences between true triodes and pentodes strapped as triodes. Here's a quotation that called my attention:

"In a pentode such as the EL34 where the screens are not tied together internally, it is possible to wire it as a "true triode". It is the only pentode I know of that is. The other ones have internal connections on the screens that can't be changed so you end up with a "Pseudo triode" as I've heard it called."

In my Triode-strapped amp, the KT-77 sounds best. I know this tube is a far relative of the EL34 and its a tetrode, but makes me wonder if anyone has got a better result with the EL34 than with the KT-77 in his Triode-wired Inspire, OTBE. I remember someone mentioning a Mullard EL34, but I cannot tell if that poster had a Triode-wired Inspire amp. I guess the only way to find out is trying one ... There goes my determination to stop chasing down new tubes [/QUOTE]

You are a bad influence/enabler.

MA I don't think you will find an EL34 that betters the GL KT77. I have the JJ KT 77's and 6CA7's that I used in a Triode Corp. TK 3488. Both are nice but the GL 77 has magic in my rig.

[o]

Mystery solved; seller checked tubes and changed ad from 300B to 350C.

[FloridaBoy]

Originally Posted by opnly bafld

Mystery solved; seller checked tubes and changed ad from 300B to 350C.

That is a 6L6 variant.

[Musica Amantem]

FloridaBoy: "MA I don't think you will find an EL34 that betters the GL KT77. I have the JJ KT 77's and 6CA7's that I used in a Triode Corp. TK 3488. Both are nice but the GL 77 has magic in my rig".

You may be right. It's just that the reference of those EL-34's being the best tubes to strap as Triodes, intrigues me. I absolutely agree with your take on the GL KT-77's.

[x3workshop]

[QUOTE=FloridaBoy;846903]

Originally Posted by Musica Amantem

Most likely a mistake.

BTW, I came across a paper from Steve Deckert (Decware) which addresses differences between true triodes and pentodes strapped as triodes. Here's a quotation that called my attention:

"In a pentode such as the EL34 where the screens are not tied together internally, it is possible to wire it as a "true triode". It is the only pentode I know of that is. The other ones have internal connections on the screens that can't be changed so you end up with a "Pseudo triode" as I've heard it called."

In my Triode-strapped amp, the KT-77 sounds best. I know this tube is a far relative of the EL34 and its a tetrode, but makes me wonder if anyone has got a better result with the EL34 than with the KT-77 in his Triode-wired Inspire, OTBE. I remember someone mentioning a Mullard EL34, but I cannot tell if that poster had a Triode-wired Inspire amp. I guess the only way to find out is trying one ... There goes my determination to stop chasing down new tubes [/QUOTE]

You are a bad influence/enabler.

MA I don't think you will find an EL34 that betters the GL KT77. I have the JJ KT 77's and 6CA7's that I used in a Triode Corp. TK 3488. Both are nice but the GL 77 has magic in my rig.

I had been running Amperex EL34's in my triode wired amp. Sweet, sweet midrange and nice upper range with respectable bass response and control. Since I moved my Inspire gear into my new office last week they lacked the low end oomph I wanted because the speakers I'm using are very inefficient - a pair of a/d/s L300C's. They are power hungry little monitors so I dropped in a pair of KT120's. Very nice for moderate listening levels now with these 4ohm monitors.

[Musica Amantem]

Originally Posted by x3workshop

I had been running Amperex EL34's in my triode wired amp. Sweet, sweet midrange and nice upper range with respectable bass response and control. Since I moved my Inspire gear into my new office last week they lacked the low end oomph I wanted because the speakers I'm using are very inefficient - a pair of a/d/s L300C's. They are power hungry little monitors so I dropped in a pair of KT120's. Very nice for moderate listening levels now with these 4ohm monitors.

Thanks for the feedback. I assume you have yet to listen to the GL KT-77, so there's no way to know if the Amperex can equal or beat it. Regarding the KT-120, other than the evident increase in SPL, have you noticed a tradeoff between body of sound and dynamics vs midrange transparency or sweetness relative to the EL34?

[x3workshop]

[QUOTE=Musica Amantem;847628]

Originally Posted by x3workshop

Thanks for the feedback. I assume you have yet to listen to the GL KT-77, so there's no way to know if the Amperex can equal or beat it. Regarding the KT-120, other than the evident increase in SPL, have you noticed a tradeoff between body of sound and dynamics vs midrange transparency or sweetness relative to the EL34?

It would be an apples to oranges comparison in this case because the amp is now in my office with small monitors. No longer at home. Whole new world and it is a less than ideal listening environment. I'm there 16hrs/day and want some decent sounds to keep the stress manageable.

That said, I like the EL34 sound (at home) for certain music (vocal/acoustic) and they don't disappoint. I have used GL KT77's in the amp (at home) and they are somewhat more robust in overall presentation, but I think the EL34's win in that sweet vocal area with a good deal of nuance.

The KT120's are simply more powerful and dynamic with good midrange, but not at the level of the EL34 and perhaps with less finesse of detail. I'm still a fan of the KT150 which is very engaging and has great 'oomph' where it counts.

I think I suffer from too many options. My power tube inventory now covers the gamut in new and vintage of almost every type.

Bottom line; different tubes for different music & mood. Happily, the tube sockets in these amps are very good quality and will take many rounds of rolling.

[FloridaBoy]

[QUOTE=x3workshop;847630]

Originally Posted by Musica Amantem

It would be an apples to oranges comparison in this case because the amp is now in my office with small monitors. No longer at home. Whole new world and it is a less than ideal listening environment. I'm there 16hrs/day and want some decent sounds to keep the stress manageable.

That said, I like the EL34 sound (at home) for certain music (vocal/acoustic) and they don't disappoint. I have used GL KT77's in the amp (at home) and they are somewhat more robust in overall presentation, but I think the EL34's win in that sweet vocal area with a good deal of nuance.

The KT120's are simply more powerful and dynamic with good midrange, but not at the level of the EL34 and perhaps with less finesse of detail. I'm still a fan of the KT150 which is very engaging and has great 'oomph' where it counts.

I think I suffer from too many options. My power tube inventory now covers the gamut in new and vintage of almost every type.

Bottom line; different tubes for different music & mood. Happily, the tube sockets in these amps are very good quality and will take many rounds of rolling.

I have some socket savers coming from a Canadian e*ay seller that were nit expensive. I'll post after they arrive.

Speakers appear to influence power tube preference. The big boys must work better with less efficient speakers. Probably due to woofer control.

[x3workshop]

[QUOTE=FloridaBoy;847655]

Originally Posted by x3workshop

I have some socket savers coming from a Canadian e*ay seller that were nit expensive. I'll post after they arrive.

Speakers appear to influence power tube preference. The big boys must work better with less efficient speakers. Probably due to woofer control.

I think the little a/d/s monitors are 86db/watt @ 4ohm sealed units. Pretty bad. Switching them out with some Acoustic Energy Aegis 1's this week for a better office setup. They're 90db/watt @ 8ohms.

Not a fan of socket savers in amps as the new manufactured ones are poor quality and suffer from voltage leakage. The old pomona and amphenol's are a different story. I do use them in my tube testers. I find some of the tube adapters suffer from the same malady.

[goldhorse]

Hi Everyone!

First time to post here.

I just got the Inspire LP-3a and Hot-Rod last night!
I live in Japan, and it took about 5 days to get here, and another 5 days to free them from the clutches of Customs (first time to import)!

I got the Hot-Rod off Ebay, and when we were exchanging e-mails afterwards, I requested Dennis to build me an LP-3a, and he did just that inside of a week. I voiced concern that the faceplate would look different from the Hot-Rod, and went right ahead and put the black faceplate and red switch cover. These look really mean up close!

They came with these complement of tubes:

LP-3a Preamplifier
Input: 6SN7 (Philco) x 2
Rectifier: 80 (Philco) x 1
Output: CV-181 (Shuguang) x 1

Hot-rod Amplifier
Input: 6SN7 (Unmarked) x 1
Rectifier: 5R4GY (RCA) x 1
Output: KT-66 (Gold Lion) x 2

Although I admit I haven't really read all of the posts in these thread, it has been very informative and it was one of the factor that convinced me to go ahead and get these. Considering these come without any documentation, every shred of information is a gem, and I found a whole mountain of it here. So, Thank You Guys!

I will be hooking these up to my system today so I'm really looking forward to hearing these. I might be asking for advice going forward so TIA.