Dennis Had Inspire Amps

[pstrisik]

Originally Posted by nhparrot

Yes the KT77's and KT88's are both current production Genalex Gold Lions.

Thanks for the heads up on the Visseaux's. Happy New Year.

Glenn

Happy New Year! Well, speaking of Visseaux, I found a pair of older Visseaux 6V6G (ST bottle). A guitar player in France. The only pair he has. The only pair of these I have ever seen. Will be a couple of weeks before I get them though. I think we are really seeing the last of decent old stock on many tubes. I'm grateful I have the chance to experience the vintage tube phenom before it is totally out of reach.

@everyone......

And, whether influenced by Dennis' power of suggestion or not, I am liking the 5U4G (RCA and GEC/British). Opened the midrange more without affecting highs or harshness. Not assessing bass however, as I currently have high pass at 90hz to the amp.

Anyone have any thoughts to share after reading Dennis' comments?

[Musica Amantem]

I thought it would be useful for the discussion to show my subjective tube-rolling results so far. The first group is the inventory of tubes I currently have, followed by my perceived relative results.

The first three columns of the configuration below relate to the preamp (LP-27a) and the rest are the amp's (SET), following the order: Input, Rectifier and Output tube in each case:

Output Tubes

NOS Russian 6L6 GT
NOS RCA 6V6 G ST
NOS RCA 6V6 GT
NOS TungSol 6AR6WA w/Adptr
Genalex Gold Lion KT-88
NOS Philco Globe-Type 27
NOS Philco 27
NOS RCA 27
NOS Sylvertone Globe-Type 56
NOS RCA-Radiotron 56

Rectifier Tubes

Sophia Electric 274-B, Octal
NOS RCA Radiotron 80
NOS Sylvania 80
NOS RCA Victor 80
NOS RCA Cunningham 80
NOS Sylvania JAN 80
NOS RAD-TEL 5Z3 (4-Pin)
NOS RCA 5Z3 (4-Pin)
NOS Brimar 5Z4 (Octal)
NOS Westinghouse-Holland 5AR4

Input Tubes

NOS RCA 6SN7 GT
NOS Sylvania 6SN7 G/B
NOS Sylvania 6SN7 GTA
NOS Super Radiotron 6SN7 GTA
NOS GE 6SL7 GT
Tung-Sol 6SL7 GT
NOS Sylvania 6SL7 GT
NOS Phillips JAN 6SL7 WGT
NOS Tung-Sol 6SL7 GT
NOS GE 6BX7 GT (got only one)

With these subjective assessment results:

6BX7 80 56 6SL7 274 B KT88 9.0 Great sound!
6BX7 80 56 6SL7 5Z3/Adpt KT88 9.0 Great sound!
6BX7 80 56 6SL7 5Z4 KT88 9.0 Great sound!
6BX7 80 56 6SL7 5AR4 KT88 8.0 Somewhat thick-sounding
6BX7 80 27 6SL7 5Z3/Adpt KT88 9.5 Great sound!
6BX7 80 27 6SL7 5Z4 KT88 10.0 Best sound!
6BX7 80 56 6SL7 274 B 6V6 GT 7.0 Lacking weight & body
6BX7 80 56 6SL7 5Z3/Adpt 6V6 GT 9.0 Great sound!
6BX7 80 56 6SL7 5Z4 6V6 GT 9.0 Great sound!
6BX7 80 56 6SL7 80/Adpt 6V6 GT 7.0 Lacking weight & body
6BX7 80 56 6SL7 5AR4 6V6 GT 9.0 Great sound!
6BX7 80 27 6SL7 5Z3/Adpt 6V6 GT 9.0 Great sound!
6BX7 80 27 6SL7 5Z4 6V6 GT 9.5 Great sound!
6BX7 80 56 6SL7 274 B 6AR6 6.0 Not neat. Lacks soundstage
6BX7 80 56 6SL7 5AR4 6AR6 7.0 Narrow soundstage
6BX7 80 27 6SL7 5Z3/Adpt 6AR6 9.0 Great sound!
6BX7 80 27 6SL7 5Z4 6AR6 7.0 Not neat. Lacks SPL
6BX7 80 56 6SL7 80/Adpt 6V6 GST 9.0 Great sound!
6BX7 80 27 6SL7 80/Adpt 6V6 GST 9.0 Great sound!
6BX7 80 56 6SL7 274 B 6L6 GT 8.0 Slightly less bass
6BX7 80 27 6SL7 5Z3/Adpt 6L6 GT 9.0 Great sound!
6BX7 80 27 6SL7 5Z4 6L6 GT 9.0 Great sound!
6BX7 80 27 6SL7 5AR4 6L6 GT 9.0 Great sound!

Obviously YMMV, and I still need to confirm some of the values again, but so far this combination of Dennis's preamp/amp is phenomenal as most everything in it sounds great.

I'll revise the suggested combinations from Dennis concerning the 5U4 (5Z3) & 6V6's vs 5AR4 & KT88's. Any suggestions/comments are welcome. My speakers are Tekton Lore 2.0's and I use a Yggdrasil DAC coupled to my laptop and Foobar as a player.

[FloridaBoy]

Originally Posted by Musica Amantem

I thought it would be useful for the discussion to show my subjective tube-rolling results so far. The first group is the inventory of tubes I currently have, followed by my perceived relative results.

The first three columns of the configuration below relate to the preamp (LP-27a) and the rest are the amp's (SET), following the order: Input, Rectifier and Output tube in each case:

Output Tubes

NOS Russian 6L6 GT
NOS RCA 6V6 G ST
NOS RCA 6V6 GT
NOS TungSol 6AR6WA w/Adptr
Genalex Gold Lion KT-88
NOS Philco Globe-Type 27
NOS Philco 27
NOS RCA 27
NOS Sylvertone Globe-Type 56
NOS RCA-Radiotron 56

Rectifier Tubes

Sophia Electric 274-B, Octal
NOS RCA Radiotron 80
NOS Sylvania 80
NOS RCA Victor 80
NOS RCA Cunningham 80
NOS Sylvania JAN 80
NOS RAD-TEL 5Z3 (4-Pin)
NOS RCA 5Z3 (4-Pin)
NOS Brimar 5Z4 (Octal)
NOS Westinghouse-Holland 5AR4

Input Tubes

NOS RCA 6SN7 GT
NOS Sylvania 6SN7 G/B
NOS Sylvania 6SN7 GTA
NOS Super Radiotron 6SN7 GTA
NOS GE 6SL7 GT
Tung-Sol 6SL7 GT
NOS Sylvania 6SL7 GT
NOS Phillips JAN 6SL7 WGT
NOS Tung-Sol 6SL7 GT
NOS GE 6BX7 GT (got only one)

With these subjective assessment results:

6BX7 80 56 6SL7 274 B KT88 9.0 Great sound!
6BX7 80 56 6SL7 5Z3/Adpt KT88 9.0 Great sound!
6BX7 80 56 6SL7 5Z4 KT88 9.0 Great sound!
6BX7 80 56 6SL7 5AR4 KT88 8.0 Somewhat thick-sounding
6BX7 80 27 6SL7 5Z3/Adpt KT88 9.5 Great sound!
6BX7 80 27 6SL7 5Z4 KT88 10.0 Best sound!
6BX7 80 56 6SL7 274 B 6V6 GT 7.0 Lacking weight & body
6BX7 80 56 6SL7 5Z3/Adpt 6V6 GT 9.0 Great sound!
6BX7 80 56 6SL7 5Z4 6V6 GT 9.0 Great sound!
6BX7 80 56 6SL7 80/Adpt 6V6 GT 7.0 Lacking weight & body
6BX7 80 56 6SL7 5AR4 6V6 GT 9.0 Great sound!
6BX7 80 27 6SL7 5Z3/Adpt 6V6 GT 9.0 Great sound!
6BX7 80 27 6SL7 5Z4 6V6 GT 9.5 Great sound!
6BX7 80 56 6SL7 274 B 6AR6 6.0 Not neat. Lacks soundstage
6BX7 80 56 6SL7 5AR4 6AR6 7.0 Narrow soundstage
6BX7 80 27 6SL7 5Z3/Adpt 6AR6 9.0 Great sound!
6BX7 80 27 6SL7 5Z4 6AR6 7.0 Not neat. Lacks SPL
6BX7 80 56 6SL7 80/Adpt 6V6 GST 9.0 Great sound!
6BX7 80 27 6SL7 80/Adpt 6V6 GST 9.0 Great sound!
6BX7 80 56 6SL7 274 B 6L6 GT 8.0 Slightly less bass
6BX7 80 27 6SL7 5Z3/Adpt 6L6 GT 9.0 Great sound!
6BX7 80 27 6SL7 5Z4 6L6 GT 9.0 Great sound!
6BX7 80 27 6SL7 5AR4 6L6 GT 9.0 Great sound!

Obviously YMMV, and I still need to confirm some of the values again, but so far this combination of Dennis's preamp/amp is phenomenal as most everything in it sounds great.

I'll revise the suggested combinations from Dennis concerning the 5U4 (5Z3) & 6V6's vs 5AR4 & KT88's. Any suggestions/comments are welcome. My speakers are Tekton Lore 2.0's and I use a Yggdrasil DAC coupled to my laptop and Foobar as a player.

Howdy Pilgrim...I knew you would get here eventually.

[FloridaBoy]

Originally Posted by robert_kc

Thanks for making me aware of Great Plains Audio. Do you own any of their products?

I see the following statement on their website, however there has been no update in more than 3 years: “Great Plains Audio is in the process of designing a whole new generation of complete loudspeaker systems for home and professional use. Watch for announcements about these exciting new systems in our GPA NEWS page.” Do they manufacture complete home hi-fi speaker systems, or just Altec drivers?

I’ve spent a little time “googling” GPA – are they still a “one man operation”?

No, I don't have any of their offerings. They are former Altec engineers that produce classic speakers. They make drivers. The enclosures can be produced locally.

[Coltrane1]

Hi all!

After spending two days revamping my room from the short wall to the long wall, big job, I took the liberty of setting up a pair of ML Theos with the following audio chain:

Dennis Had Inspire Fire Bottle KT88 SET amp - 12 watt SET amp featuring Sophia Electric Princess 274B mesh tube rectifier
Dennis Had Inspire LP2 preamp featuring same rectifier as above
Martin Logan Theos
Martin Logan Depth i sub
PS Audio PerfectWave DAC II, sampling music via iTunes attended to by Channel D's Pure Music 3

As you can observe, preamp volume setting is only at 10 o'clock, and even at that there's far more volume than I'm accustomed to for my normal listening level.

Before trying this experiment today I suspected the amp would drive the 4 ohm impedance Martin Logan Theos adequately, as years ago I did a similar experiment driving a pair of ML CLSiiz's with an 8 watt SET integrated. Crazy I know. But tube power rules.

Small watt tube amps and ML's work for jazz...I've never conducted a sampling of rock...so ymmv...same goes for demands presented by home theater listening...but keep an open mind. Tubes and 'stats have always been a match made in heaven.

I'd acquired this Inspire pre/amp combo 2 years ago and they've been collecting dust as I'd only bought them to drive a pair of Cain&Cain Abby single source drivers...the blonde pair in the video...which have their own sub, known as a "Bailey."

My apologies for the messy room...between Xmas, and revamping a wall full of gear from one wall to another it's been a big job...The video was quickly done via an iPhone. I'll do a proper video later when I've finished the room setup. I wanted Dennis to know that his amp effortlessly drives a pair of electrostat's to more than adequate listening levels. The sensitivity rating of the Theos is 90dB. Maybe this wouldn't work for HT, but for 2 channel audio it's more than enough volume for my modestly sized room.

[ame="https://www.youtube.com/watch?v=jlR9B22kOiM"]https://www.youtube.com/watch?v=jlR9B22kOiM[/ame]

[Musica Amantem]

Howdy FB, nice to be here! Thanks for your always timely and accurate support in putting together this great sounding gear.

[FloridaBoy]

[QUOTE=pstrisik;749919]Happy New Year! Well, speaking of Visseaux, I found a pair of older Visseaux 6V6G (ST bottle). A guitar player in France. The only pair he has. The only pair of these I have ever seen. Will be a couple of weeks before I get them though. I think we are really seeing the last of decent old stock on many tubes. I'm grateful I have the chance to experience the vintage tube phenom before it is totally out of reach.

@everyone......

And, whether influenced by Dennis' power of suggestion or not, I am liking the 5U4G (RCA and GEC/British). Opened the midrange more without affecting highs or harshness. Not assessing bass however, as I currently have high pass at 90hz to the amp.

Anyone have any thoughts to share after reading Dennis' comments?QUOTE]

1) Using different rectifiers does not change the sound of the input tube.
2) The same rectifier and power tube combination will sound different with different speakers.
3) The low voltage drop rectifiers should NOT be used unless you are sure the power tube can handle the increased voltage to the plates.

[FloridaBoy]

Originally Posted by robert_kc

I recently spent about 30 minutes auditioning the DeVore O/93 speakers with an Audio Research tube amp that was not equipped with tone controls. (I think it was a VSi60.) The O/93 speakers put out a lot of sound for a speaker with 2 drivers – however the high frequencies were too “bright” for my taste. The highs sounded “separate from” the music. My attention was constantly drawn to the high frequencies vs. the music. I never “got lost in the music” when listening to the DeVore O/93 - I was always aware that I was listening to speakers. (The fact that there were no grill covers may have contributed to my attention being constantly drawn to the high frequency drivers.)

I auditioned the O/93s listening to classical music. My reference is live classical music in a world-class symphony hall. Of course the DeVores have received some very favorable reviews, and you might like their sound.

I wonder if I might like the sound of one of the DeVore speakers if paired with the right amp – perhaps equipped with tone controls so that I could attenuate the treble. I’ve not heard the new DeVore “gibbon X”, and I’m curious about how it sounds.

Have you heard Klipsch RF-7 II speakers paired with a tube amp? As I mentioned earlier my Inspire SE Stereo Tube Amplifier HO (when equipped with 6DJ8, 5AR4, and GT-6L6-GE) delivers excellent sound quality with the Klipsch, with plenty of deep bass. With some amps I need tone controls to tame the RF-7’s high frequencies, but not with the Inspire SET amp. For big band music there is plenty of “punch” (i.e., dynamics). And for opera there is plenty of clean high frequency power to handle a soprano’s voice. (Actually I have one RF-7 on one channel, and an RF-7 II on the other. It’s a long story – I merged 2 separate mono systems into one stereo system.)
I have limited opportunities to audition speakers, because there are few retailers with demo rooms where I live. I wish that I could hear the Tannoy Kensington GR. Has anyone heard it?

Klipsch & tubes are excellent...especially the Heritage series. Horns cannot be beat for scale and dynamics. The Inspire gear is a great match. I brought my amp & pre to a friends house and he was amazed with them driving highly modified, Volti kit, Belle Klipsch a dressed up La Scala...so was I. Dead quiet on 104db speakers.

Klipsch Upgrades by Volti Audio is a good place to start.

Me? I'm driving Heresy III's because they are a good fit for my room. I had La Scalas for 23 years.

[robert_kc]

Originally Posted by FloridaBoy

Klipsch & tubes are excellent...especially the Heritage series. Horns cannot be beat for scale and dynamics. The Inspire gear is a great match. I brought my amp & pre to a friends house and he was amazed with them driving highly modified, Volti kit, Belle Klipsch a dressed up La Scala...so was I. Dead quiet on 104db speakers.

Klipsch Upgrades by Volti Audio is a good place to start.

Me? I'm driving Heresy III's because they are a good fit for my room. I had La Scalas for 23 years.

I’ve never heard the LaScala, Belle or Klipschorn (or Altec 19, etc). I’d like to hear them someday – driven by tubes, and playing classical music. (I did briefly own a Cornwall, but didn’t care for the sound – IIRC the bass sounded “muddy”.) Does anyone use these traditional horn-loaded speakers for classical music? If so, I’d like to hear your comments.

I’m also aware that some small companies manufacture up-grades to these classic speakers, and some manufacture entire speaker systems that they claim are superior to the originals. Again, I wish that I could hear them.

And some people say that the speakers to own are the Klipsch Jubilee.

Unfortunately I can’t accommodate speakers that are more than 2 feet wide (or in the case of Jubilee more than 3 feet wide) into my listening rooms, except perhaps in my basement (which is where my Klipsch RF-7s reside). I think that a lot of people are in the same boat, which is why tower speakers are so popular.

Maybe someday I’ll get to hear one of these classics …

[Coltrane1]

Originally Posted by pstrisik

Fellow Inspirerers:

Dennis generously described some about his design thoughts, particularly with relevance to the current rectifier thread of conversation here.

I'm digging back a ways and giving an old RCA 5U4G a try after reading what he says.

Hi Peter! Thanks for posting Dennis' thoughts. So is the 5Y3 "GT" an acceptable rectifier option one could consider for the 'fire bottle KT88'? I'm seeing a lot of NOS pairs on the 'bay.

Happy New Year!

Greg