SET amps.............

[kev313]

"Set amplifiers are adversely effected by wild impedance swings..."

Where do you think that magic midrange comes from?

 

Here we go again......

 

eh...whatta expect from a guy who uses a diagram of a ****** for an avatar. (Is there really a speaker in there?) : -)

[seti]

I think I do have someone in Arkansas.

If they are up for auditions or plan to attend any audio events I would really love to hear them sometime. They come in at a whopping 55lbs zowee man. The easy bias is also very cool.

What are your favorite KT88 tubes?

Are you close to El Dorado? I like the tubes we ship it with - the EH KT-88. The Valve Art was nice too. Yeah, they took take some space and a sturdy shelf!

El Dorado is down close to the Louisiana border. The roads down that way are fairly crappy. It is about a 3 hour drive. Wish I knew more people in that part of the state.

[SWL]

If you get down to Chicago, let me know. I don't have any Klipsch in the house (feel free to bring yours!), but you can hear some Wright Sound 2a3 SET amps on single driver speakers (PHY-hp based).

I'm in the NW burbs almost every weekend and check out Saturday's Audio pretty frequently. Thanks much for the invite.........I would definitely like to get a listen.[]

In fact, I will be attending the AK (tube) fest next Saturday in Northbrook. I'm bringing my JM Peach, other members are bringing tube pre's, tube cdp's, tube amps and various speakers. I'm curious to check out the Dynaco ST-70..........seems like they're everywhere.

[seti]

I listened to my 8wpc SET on Cornwall and Heresy. They never sound as good as on my Belles. I think the increased sensitivity is a big help imo and another important factor is preamp selection. When I listened to my 8wpc SET on my Belles with preamps with low to average gain it just sounded ok. The George Wright preamp had a high gain switch and the difference was apparent. This was just from my observations with my equipment. I could be totally off but it seems like a correct assumption to me.

[Marvel]

If you get down to Chicago, let me know. I don't have any Klipsch in the house (feel free to bring yours!), but you can hear some Wright Sound 2a3 SET amps on single driver speakers (PHY-hp based).

I'm in the NW burbs almost every weekend and check out Saturday's Audio pretty frequently. Thanks much for the invite.........I would definitely like to get a listen.

In fact, I will be attending the AK (tube) fest next Saturday in Northbrook. I'm bringing my JM Peach, other members are bringing tube pre's, tube cdp's, tube amps and various speakers. I'm curious to check out the Dynaco ST-70..........seems like they're everywhere.

Kev, I'm curious how you would compare the Wright's with your Moondogs. Maybe you wish you hadn't passed them on to someone else?

Bruce

[Deang]

"...whatta expect from a guy who uses a diagram of a ****** for an avatar..."

If I squint really hard I can almost see a uterus -- no ****** in sight though.

[oldtimer]

Push! Pull! Push Pull! Oh baby just keep doin that you know where it's at..

[Deang]

http://www.stereophile.com/integratedamps/398/index4.html

[Marvel]

Dean, the second reviewer puts rocks on top of his gear to stop resonance.... That is REAL Voodoo!

[seti]

http://www.stereophile.com/integratedamps/398/index4.html

For all you guys buying your amps based on spec sheets, Dean's link is a must read and will spare you from buying the wrong amp!

However, for the people who LISTEN to actual music on their speakers, here's what THAT review had to say about the amp during LISTENING tests.

Quote: " After some critical listening evaluations—and many more hours of sheer musical magic—I've become convinced that single-ended tube amplifiers sound fabulous in spite of their distortion, not because of it."

Quote:" It was unmistakable, however, that the 300SEI communicated the music in a way I'd never experienced before. There were an immediacy and a palpability to the sound that were breathtaking. I don't mean a sonic immediacy, such as a forward character, but a musical immediacy that riveted my attention on the music. On the superb new classical-guitar duo Baroque Inventions (Dorian DOR-90209), for example, I had the distinct impression of sitting in front of the two guitarists in the Troy Savings Bank Music Hall. The 300SEI benefited from the low playback level called for by the instrumentation, producing a realistic level with this small-scale music."

Quote:"This liquidity and lack of electronic artifact produced a relaxation and intimacy with the music that made me want to play records and CDs long into the night. In fact, I spent night after night totally immersed in the musical experience provided by the 300SEI and the Compositions."

Quote: "Instrumental timbre sounded astonishingly real—a quality most apparent on violin. When you hear violins in a concert hall, they're never shrill, screechy, or strident. So it was with the 300SEI, which reproduced solo and massed violins with a warmth and beauty unmatched by any electronics I've had in my system. Similarly, the 300SEI's rendering of the human voice was glorious. The amplifier restored the human quality to vocals, making them more lifelike, present, palpable, and expressive. Listen to Doug MacLeod's Come to Find (AudioQuest AQ-CD1027) through the 300SEI to hear this presence and directness of expression I'm describing. The 300SEI's portrayal of the harmonic structure of instruments and voices just sounded more like the real thing, with less of the mechanical, synthetic sound we've assumed has been inherent in music reproduction."

I think it's fair to say, he liked the sound of it.

Oh god I hate reading equipment reviews. I don't read reviews but speaker wire reviews can be worth a couple giggles.

I really would like to hear some high powered high quality 211 or 845 based amps. Has anyone on the forum listened to a pair of AirTight amps.

[oldtimer]

everyone please put voodoo chile on the tt or cd if you must, crank it and enjoy.

[seti]

I listened a lot to the AudioNote 211s and a very nice 845 - both with Audio Note speakers. I was not as taken as I thought I should have been, or might have been. There is an ominous "visual" expectation when you see that monster oraange glow, and you really have to be careful not to get sucked into the visual association. Anyway, a very nice SET sound, but definitely not more exquisite than many 2A3 designs, although obviously more powerful. I would imagine if you had 90dB speakers and just had to have SET, those amps at 25W or 30W might be the right choice. In short, I think they have more power, but no great increase in clarity or transparency that I could tell.

That is very interesting but I would want to hear them on my Belles or Khorns in order to compare. The Audio Note gear looks very nice. It is hard for me to listen to gear and try to think how that would sound on my speakers in my room. I just can't do it my ears and brain just don't work like that not to mention I would need a couple weeks of listening. I've only heard the 45 and 2a3 tubes a couple of times and they are nice but I love the 300Bs a tad more. Perhaps I should start reviewing gear so I can listen to more of whats
available. Ah hell that would never work as I'm a crap writer.

[oldtimer]

crap writing is the only kind that sells seti.

[Erik Mandaville]

I've compared the Wright and Welborne 2A3 amps with both Klipschorns and Heresies. While they are both 'good' enough to provide, for me, long term listening enjoyment with either speaker, I ultimately preferred the Wright to the stock Moondog. Being very familiar with the circuits of both, I think there are some concrete reasons behind why the Wright 2A3s were not only quieter in terms of AC related filament hum, but also seemingly a little more extended at the frequency extremes.

The Moth Audio Si 2A3, however, has come to be my favorite of any SET amp I have had or heard, including parallel-feed output topologies; however I am quite sure that I liked the parafeed output to both the Wright and the Welborne amps. My Welborne lab monoblocks are very far from stock however, and the changes made in the input/driver stage, as well as modifications for 300B use on the output (thanks again Jim!) have made for a really wonderful sounding amplifier with both Klipschorns and Heresies.

When we got the Moth, though, they were no longer being produced by Moth Audio. I bought it in the form of parts and an accompanying schematic. It's direct-coupled (not a single coupling capacitor), and provides a very clear and open sound that is somehow more powerful or large, maybe, than other SET amps I've used and also enjoyed.

It's nice to see some positive discussion about this kind of amplifier. I don't use mine for HT and movies, though, preferring the bigger horsepower of push-pull El-34s for that.

Try for yourself, you might like them. I agree with all that has been said about simplicity of crossover design with such low power.

Erik

[Deang]

"When you hear violins in a concert hall, they're never shrill, screechy, or strident."

Yeah, right -- has this guy ever heard a violin?

I find that if like the way somethings sounds, then find out it measures badly -- it doesn't sound so good anymore. I conclude that my ears have been tricked -- and that truth in reproduction lies in a different direction.

It wasn't my intent to stir things up or ruin the thread. I probably should have PM'd my comment to Craig.

[Deang]

I said, "measures badly", with an emphasis on "badly" -- and I sure as hell never said I "ruled hearing out". Now, what is "silly and disengenous" is to call yourself an "Engineer" and flippantly discount the impact of high output impedance on the frequency response of an amplifier with a loudspeaker load. Red Herring indeed. It's only a Red Herring if you like or build amplifiers with limited bandwidth and can't deliver flat response except with a dummy resistor. Let's get real here, that Cary amplifier is basically a 40lb. equalizer that will "change its settings" with every speaker you connect it to. Earlier in the thread you shared the design goals of the pCat, and I'm sure those goals were met without one iota of concern regarding the output impedance.

[Erland]

I just like to show you my new DIY Borderpatrol 300B with the massive psu's to go with them.

You have not heard SET before you have heard this!

The two cabinets in the center are the valve rectified powersupplies with choke filters

The cabinets on the side are the amps itself. The round, rather large "pot's" are the Hørning" torroid output transformers.

This may be the ultimate way to "feed" a Khorn.

Anyone on this forum passing through Norway, are welcome to drop by and experience Khorn as I think it should be!

[Tarheel]

Very nice equipment and set up Erland. I will take you up on your offer if I ever get to Norway but by then it would all be vintage gear......still good just older[]

[kev313]

http://www.stereophile.com/integratedamps/398/index4.html

 

 For all you guys buying your amps based on spec sheets, Dean's link is a must read and will spare you from buying the wrong amp! 

However, for the people who LISTEN to actual music on their speakers, here's what THAT review had to say about the amp during LISTENING tests.

Quote: " After some critical listening evaluationsand many more hours of sheer musical magicI've become convinced that single-ended tube amplifiers sound fabulous in spite of their distortion, not because of it."

Quote:" It was unmistakable, however, that the 300SEI communicated the music in a way I'd never experienced before. There were an immediacy and a palpability to the sound that were breathtaking. I don't mean a sonic immediacy, such as a forward character, but a musical immediacy that riveted my attention on the music. On the superb new classical-guitar duo Baroque Inventions (Dorian DOR-90209), for example, I had the distinct impression of sitting in front of the two guitarists in the Troy Savings Bank Music Hall. The 300SEI benefited from the low playback level called for by the instrumentation, producing a realistic level with this small-scale music."

Quote:"This liquidity and lack of electronic artifact produced a relaxation and intimacy with the music that made me want to play records and CDs long into the night. In fact, I spent night after night totally immersed in the musical experience provided by the 300SEI and the Compositions."

Quote: "Instrumental timbre sounded astonishingly reala quality most apparent on violin. When you hear violins in a concert hall, they're never shrill, screechy, or strident. So it was with the 300SEI, which reproduced solo and massed violins with a warmth and beauty unmatched by any electronics I've had in my system. Similarly, the 300SEI's rendering of the human voice was glorious. The amplifier restored the human quality to vocals, making them more lifelike, present, palpable, and expressive. Listen to Doug MacLeod's Come to Find (AudioQuest AQ-CD1027) through the 300SEI to hear this presence and directness of expression I'm describing. The 300SEI's portrayal of the harmonic structure of instruments and voices just sounded more like the real thing, with less of the mechanical, synthetic sound we've assumed has been inherent in music reproduction."

I think it's fair to say, he liked the sound of it.

The conclusion of the measurements section: I can easily imagine the non-listening audio-engineering community looking at these measurement results and laughing at audiophiles who must "like the sound of distortion." But after close critical scrutinyboth in the listening room and the test labI'm convinced that the 300SEI doesn't harm the signal in some of the ways push-pull amplifiers do, and that what the 300SEI does right is beyond the ability of today's traditional measurements to quantify. Further, I didn't enjoy the 300SEI so much musically merely because it introduced frequency-response deviations and added lots of low-order harmonic distortion. Instead, the 300SEI's fundamental musical rightness overcame its limitations.Robert Harley

[seti]

I listened a lot to the AudioNote 211s and a very nice 845 - both with Audio Note speakers. I was not as taken as I thought I should have been, or might have been. There is an ominous "visual" expectation when you see that monster oraange glow, and you really have to be careful not to get sucked into the visual association. Anyway, a very nice SET sound, but definitely not more exquisite than many 2A3 designs, although obviously more powerful. I would imagine if you had 90dB speakers and just had to have SET, those amps at 25W or 30W might be the right choice. In short, I think they have more power, but no great increase in clarity or transparency that I could tell.

That is very interesting but I would want to hear them on my Belles or Khorns in order to compare. The Audio Note gear looks very nice. It is hard for me to listen to gear and try to think how that would sound on my speakers in my room. I just can't do it my ears and brain just don't work like that not to mention I would need a couple weeks of listening. I've only heard the 45 and 2a3 tubes a couple of times and they are nice but I love the 300Bs a tad more. Perhaps I should start reviewing gear so I can listen to more of whats
available. Ah hell that would never work as I'm a crap writer.

Absolutely correct. Do what our friend Thuper did over in Norway!

Yeah you mean collect them all I wish I could.