SET amp owners thread

Kingrex

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A Line Magnetic Lm508ia (with either a Microzotl preamp or Shindo pre) into Pureaudioproject Pap horns or Harbeth 40.2s but not Magnepan 20.7s, well not yet at any rate... indecision is clearly a strong point here. I may yet modify the Pap horns, I would love to maybe modify the 20.7s with neodymium magnets, I wouldn’t change a thing on the Harbeth 40.2s...

I have done loads to my horns. The best 2 mods are remote mount the crossover and use good wire to lace the drivers to the crossover. The second is I put my speakers on 50 lb blocks of engineered laminate wood, 9 inch tall. I put compressed insulation board under the block to protect my floor's. Holy cow. The bass is far far better. The horn more inline with the ear. I think reflection off the floor reduced. Putting them on the blocks was a big improvement. Cables and remote crossover removed all the fatigue.

I still wonder about a better horn driver.
 

Kingrex

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I have done loads to my horns. The best 2 mods are remote mount the crossover and use good wire to lace the drivers to the crossover. The second is I put my speakers on 50 lb blocks of engineered laminate wood, 9 inch tall. I put compressed insulation board under the block to protect my floor's. Holy cow. The bass is far far better. The horn more inline with the ear. I think reflection off the floor reduced. Putting them on the blocks was a big improvement. Cables and remote crossover removed all the fatigue.

I still wonder about a better horn driver.
PAP trio 15 horn
 

the sound of Tao

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I have done loads to my horns. The best 2 mods are remote mount the crossover and use good wire to lace the drivers to the crossover. The second is I put my speakers on 50 lb blocks of engineered laminate wood, 9 inch tall. I put compressed insulation board under the block to protect my floor's. Holy cow. The bass is far far better. The horn more inline with the ear. I think reflection off the floor reduced. Putting them on the blocks was a big improvement. Cables and remote crossover removed all the fatigue.

I still wonder about a better horn driver.
I’m just very happy with the paps now, don’t want to spoil the magic. So I will play at another horn but use the Paps as they are as my benchmark. External crossover on the paps was also a really great move for me. Great to hear you are enjoying yours.
 

advanced101

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My speakers are 98 db/m, pretty efficient. I have easily run them with the LM 219ia. What SETs should I be looking at? The LM 845 monos look interesting, Kronzilla SX, Allnic 311M, etc. I haven’t been a fan of 300b, at least ones I have found. Someday I may go horns, the hORNS Universum look interesting, I will try and find a pair to audition.
 

spiritofmusic

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I would recommend Nat. Models ranging from 70W, to 130W and 170W. Hugely impressive sound, weighty and textured, but with a very natural delivery. Not the euphonic wamth I hear in BAT or the slightly lightweight sound of Audion.

My 70W Nats power my 101dB Zus in a 150 cubic m room to a really saturated presentation at moderate volume levels.
 
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bonzo75

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My speakers are 98 db/m, pretty efficient. I have easily run them with the LM 219ia. What SETs should I be looking at? The LM 845 monos look interesting, Kronzilla SX, Allnic 311M, etc. I haven’t been a fan of 300b, at least ones I have found. Someday I may go horns, the hORNS Universum look interesting, I will try and find a pair to audition.

You can audition the universum near Birmingham with analog. In fact my videos have Allnic 7000v playing in that system during those videos with only an AT33. The Allnic 300b and kronzilla are both very good. Just different. But how many watts is your LM?
 

advanced101

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The LM219 was 22 watts. Thought it was good, but lacked that last little bit off bass that my EAR amps have. I now run subs, so bass isn't an issue. I have heard of people successfully running my speakers with 10 wpc. Btw, Birmingham, in the US or elsewhere?
 
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Kingrex

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How does a 2A3 - 4 to 6 watt Whammerdyne amp make good bass with my Pure Audio Project trio 15 horns. I hear the PAP shows with the amp, and a rep from PAP says they are the best of the best with my speakers. I get musical, but what about some meat on the bones. I currently use a 50 or so watt KT88 pentode amp. Is there really no comparison. I have Transition Audio Altec 1570 B with 811A tubes. Thats 140 or so watts. Much thicker sound than the KT88 pentode. Altec is not as clean and clear. Not as accurate to there real instrument.

I want great recreation of real instrument sound. Fast. I don't want mud, but I do want depth and richness. Not lean and clean. Warm and clean and accurate. Truthful to the source.
 

213Cobra

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I've been using SET amps for over 20 years but didn't originate my interest via the SET cult community. My speakers are 101db/w/m, so several db more efficient than PAP (which I've heard), depending on which version and vintage of the Trio 15 you have. It's true that a competently-designed and built 2a3 SET amp can produce truly excellent bass character and with Joourney-to-the-Center-of-the-Earth excavating depth. It's easier to get uncompromised deep bass out of a 2a3 than from a 300B design, generally. But when people say that 4-6 watts of triode power is perfect for a 90-96 db/w/m/ speaker, you have to start querying their true listening habits, particularly for how much they value dynamic life in their music listening, and then actually indulging in it. I don't know where you are, but for example, a Tokyo-dwelling SET / hi-eff speaker listener espousing the perfection of 2w 45 SET amps or 4w 2a3 sound, has to be inferred considering his or her context. They may have much different priorities than you.

In other words, a great 2a3 SET amp can qualitatively deliver convincing bass through your PAP trio 15s, but will it be musically-convincing if you value dynamic life in your music, and sense a looming ceiling on headroom? That depends on you, your room, your habits and expectations.

I stopped trying to get rich sound out of KT88 tubes 20 years ago. There is just something there that puts a little grit and gloss in sound that doesn't belong there. KT66 is more interesting and musical, along with its 6L6 counterpart, and of course the venerable EL34 when you can find good ones. I am not surprised you find your 811 amp too thick. I think for your speakers (what are your room dimensions?) a better combination of power and single-ended incisiveness is likely called for. You mention you don't want "lean and clean," but instead "warm and clean and accurate; truthful to the source." But isn't there a contradiction in that wish? "Warm" is almost never truly accurate, but it is euphonic. Can "warm" be truthful to the source if the source is "cold" or "lean and clean?"

I find that a well designed 2a3 push-pull amp can really help here. You'll get about 13 w, bass can be phenomenal, and if the design is simple, it will be absent the subtle grit of crossover notch distortion. But if you want that 4w purity with more oomph, you can have a 2a3 PSET amp built for roughly the same output. You need the amp to have an oversize power supply and simplicity for fast, agile, communicative sound. You'll get enough warmth without the bloat common in many (not all) 300B implementations.

845 amps provide another path for SET with much more shove. Not long ago, most 845 tube options brought anywhere from a little to a lot of thickness with them. That's been changing. Psavane, Elrog and KR have exotic (and expensive) options. But Tube Amp Doctor has the relatively new Shuguang 845C Iron Plate 845 built for 95w dissipation rating. The earlier 70w dissipation 845C metal plate had a bright, fleet-footed voicing but many 845 amps had to be re-biased for it lest it cherry with short life. The new iron plate has higher heat dissipation and can be dropped into almost any 845 amp. It is noticeably quicker than the 845B and other graphite tubes, and when combined with an intrinsically fast and transparent design like the Audion Black Shadow, it delivers a particularly objective sound.

Another option is something I haven't seen on the market yet but which I am thinking about commissioning. The KT150 tube is the best sounding of the modern production kinkless tetrode tube designs I've heard. A single-ended tetrode amp using the KT-150 should yield a solid 25w. Paralleled, you can get to 40-50w. Push-pull, 60 - 75w. Single-ended pentode-and tetrode amps can resolve the conflict between SET purity and pentode/tetrode push-pull compromise. And you get some interesting alternatives aside from KT66, EL34, 6L6. The NOS German EL156 and F2a are particularly interesting for their combination of bandwidth, linear performance and exceptionally long life for power tubes.

But I fully understand if you want to stick with SET. Before you commit to 4-6 watts via 2a3 SET, understand the priorities of the person recommending that, and find a way to listen to your system, in your room, on music that is vital to you, to determine whether it works for you. For me, on 101db/w/m speakers and a 21'x14'x8.5' only partially bounded space, a 4w 2a3 SET amp is one tool in the shed. But most of the time it would be benched, because the headroom ceiling is palpable on highly dynamic music.

Phil
 
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bonzo75

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The LM219 was 22 watts. Thought it was good, but lacked that last little bit off bass that my EAR amps have. I now run subs, so bass isn't an issue. I have heard of people successfully running my speakers with 10 wpc. Btw, Birmingham, in the US or elsewhere?

I meant Birmingham UK and travel is now closed so I doubt you will get a chance to audition. Strange that people are getting it with 10w and you are not getting enough bass with 22. Must be difference in LM power supply or transformer.

Kronzilla bass is excellent, and drive. Silvercore 833c is more nuanced than kronzilla and good drive but not same level and not same bass

Lower wattage amps have more nuance but except for very few speakers, they lack drive and headroom. Then you really have to get into a good match.

The Allnic A6000 is very musical, again sufficient power and drive for a horn. It will be more musical than kronzilla, we have directly compared and used price is good, but you will need 8 Elrog or KR 300b tubes.
 

bonzo75

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How does a 2A3 - 4 to 6 watt Whammerdyne amp make good bass with my Pure Audio Project trio 15 horns. I hear the PAP shows with the amp, and a rep from PAP says they are the best of the best with my speakers. I get musical, but what about some meat on the bones. I currently use a 50 or so watt KT88 pentode amp. Is there really no comparison. I have Transition Audio Altec 1570 B with 811A tubes. Thats 140 or so watts. Much thicker sound than the KT88 pentode. Altec is not as clean and clear. Not as accurate to there real instrument.

I want great recreation of real instrument sound. Fast. I don't want mud, but I do want depth and richness. Not lean and clean. Warm and clean and accurate. Truthful to the source.

2a3 is fast clean sound in the highs, but issue with open baffles like PAP is Midbass and below. That's usually their weakest link and if you sorted that out fine. This is where horn loaded cabinets kick ass
 
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Kingrex

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I'm not going back to my speaker. I will stick with finding the right amp for the speaker. I like the sound from my speaker. It's good enough.

My room is 18x20x9 and has open boundries to the rest of the house. I probably listen in the mid 80 db range. I don't play loud. Would rather the magic happen at lower volumes. In the 70dbs.

At 54, I still have exceptional hearing. When I got my kt88 amp I was shocked at how much more accurate and real the tone was. It gave me a better understanding of what could be obtained. How close to live sound could be.

I want to keep my $ at say $6k. Happy to get used. Warranty don't usually mean much. Ampsandsound wanted me to spend $600 to ship my amps back (for a second time in 1.5 years) because the bios cap had failed. I had a local guy swap the cap. Justin the owner said he would never service my amp again. I guess he did not like my feedback. His amp hums pretty loud. When the local power gets bad at night it roars. Hard to relax in front of tv when in idle as the hum is so loud. So, any new amp needs a good regulated power supply that can deal with dc and spurious voltage that gets between the neutral and ground. Otherwise I'm jumping out of a pot.

I mention Whammerdyne as Pat says his amp is built as such and dead quiet. Its power supply can handle the utility noise. Of course any noise via my preamp or sources will only be amplified. I get that.
 

shadowlight

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I’ve had a LM508IA for the Pap horns for the last year and now just taken delivery of a LM805ia to now drive the Harbeth 40.2s. These amps are impossibly good if given a good pre. Possibly my favourite amp ever... do love them. They are awesome. Enjoy.

I thought both those were integrated amps? Are you saying the built in preamp section is not as good. I also have PAP Horn setup and was looking at LM integrated as an option. So your experience and feedback is greatly appreciated.
 
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shadowlight

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I'm not going back to my speaker. I will stick with finding the right amp for the speaker. I like the sound from my speaker. It's good enough.

My room is 18x20x9 and has open boundries to the rest of the house. I probably listen in the mid 80 db range. I don't play loud. Would rather the magic happen at lower volumes. In the 70dbs.

At 54, I still have exceptional hearing. When I got my kt88 amp I was shocked at how much more accurate and real the tone was. It gave me a better understanding of what could be obtained. How close to live sound could be.

I want to keep my $ at say $6k. Happy to get used. Warranty don't usually mean much. Ampsandsound wanted me to spend $600 to ship my amps back (for a second time in 1.5 years) because the bios cap had failed. I had a local guy swap the cap. Justin the owner said he would never service my amp again. I guess he did not like my feedback. His amp hums pretty loud. When the local power gets bad at night it roars. Hard to relax in front of tv when in idle as the hum is so loud. So, any new amp needs a good regulated power supply that can deal with dc and spurious voltage that gets between the neutral and ground. Otherwise I'm jumping out of a pot.

I mention Whammerdyne as Pat says his amp is built as such and dead quiet. Its power supply can handle the utility noise. Of course any noise via my preamp or sources will only be amplified. I get that.

I currently use Triode Labs 2a3 Classic amp with my Quintet15 and the sound is wonderful, but always wondering what additional watts would provide.
 

213Cobra

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I'm not going back to my speaker. I will stick with finding the right amp for the speaker. I like the sound from my speaker. It's good enough.

My room is 18x20x9 and has open boundries to the rest of the house. I probably listen in the mid 80 db range. I don't play loud. Would rather the magic happen at lower volumes. In the 70dbs.

At 54, I still have exceptional hearing. When I got my kt88 amp I was shocked at how much more accurate and real the tone was. It gave me a better understanding of what could be obtained. How close to live sound could be.

I want to keep my $ at say $6k. Happy to get used. Warranty don't usually mean much. Ampsandsound wanted me to spend $600 to ship my amps back (for a second time in 1.5 years) because the bios cap had failed. I had a local guy swap the cap. Justin the owner said he would never service my amp again. I guess he did not like my feedback. His amp hums pretty loud. When the local power gets bad at night it roars. Hard to relax in front of tv when in idle as the hum is so loud. So, any new amp needs a good regulated power supply that can deal with dc and spurious voltage that gets between the neutral and ground. Otherwise I'm jumping out of a pot.

I mention Whammerdyne as Pat says his amp is built as such and dead quiet. Its power supply can handle the utility noise. Of course any noise via my preamp or sources will only be amplified. I get that.
You seem a good candidate for Whammerdyne. I've heard one amp once and was impressed. Design approach and engineering are first rate. The amps are built with substantial power supplies with close to 3db of clean dynamic headroom and they are very quiet. They have one amp under $6000. Because of your room size and it being unbounded, finding a way to stretch for the $8500 DAM2 monos (or finding a pair used -- difficult -- for less) would I think remove any risk of sensing insufficient power, given your listening habits and preferences. Given your power problems, an isolation transformer might be in your future.

Phil
 

Kingrex

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Whats up Shadowlight. Didn't you get me Qobuz a year ago. Been a while. You also put on a PAP show at your house? I love my PAP. I put mine on 9" tall super dense engineered beam. Depth and output of bass is much greater. Less smear from first reflection off floor. I have been telling Thomas they should offer a base attachment that lifts the speaker 9" is a option. I told him how to build it. Super simple and light. Easy to ship. He ignores me on that topic.

He said the Whammerdyne sound as good as it gets. But he is really a SS fan as far as I know. He says the Pass has way more umph and bass power. The Whammerdyne is more truthful.
 

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Kingrex

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. Given your power problems, an isolation transformer might be in your future.

Phil[/QUOTE]
Isolation transformer sound horrible. I have tried a few. They do knock noise down. But you hear them all. I believe it is better to get gear built to handle the noise. My other equipment does not seem that sensitive to it.

I just bought a new fluke meter. Been working with an engineer on how to rid spurious voltage that builds between the ground and neutral. You know, the voltage that just happens when you put 2 wires next to each other and pass current through them (inductance). I have been able to knock it down from 70 volts to 52 volts at a friend house. I need to do some more work to get it under 20 volts.

Harmonics off the utility are more a problem I cant solve without physical equipment. Physical equipment always seems to change the sound. It's just not as musical. So far. Great minds are still working on ways to solve the issue.

But I'm degressing. I do see a few of those Black Shaddow show up used. They appear to be 92 db quiet. Hmmmmm. The Whammerdyne says they are 115 db quiet. That's a big difference. I wish I know what my amps were to have a baseline.
 

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