SET amp owners thread

christoph

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I have two systems. One is Vintage based on Tannoy Autograph with Allnic T-1610 SE and the Pre Amp is Allnic L-8000. I have two phono amps, one is Allnic H-5000. All Allnic amps were deeply modified. The second phono eq is the original EMT-139ST integrated on EMT-927 TT.
The second system is based on Wilson Alexx with Krell Evo-1 and Evo-2. Both systems share analog sources.
It is possible, I'd like your opinion between KR and Lamm powers.
Nice systems :cool:
As much as I like the Lamms for more demanding Speakers like the Acoustats and the Apogee Scintilla (a match in heaven with the 1 Ohm Scintilla and the Lamm hybrid monos), I do prefer SETs on my horn speakers and my Apogee Studio Grands ;):D
 
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Dante Choi

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Nice systems :cool:
As much as I like the Lamms for more demanding Speakers like the Acoustats and the Apogee Scintilla (a match in heaven with the 1 Ohm Scintilla and the Lamm hybrid monos), I do prefer SETs on my horn speakers and my Apogee Studio Grands ;):D
I never experienced Lamm and really now I'm very curious about these electronics specially for my Wilson Alexx. These speakers are with relatively high efficiency (91db) but complicated impedance in 3000hz with 1.5ohm... very difficult for low powered valves... Several years I ago I used Apogee Studio Grand bi-amplified with Krell and ML. How you are using it?? Amplified with SE?? I can't belived!
 
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chaccone

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I replaced my Yamamoto A08s (EML 45 and 80) with the Thoress 845 monoblocks. While I have read the reviews from Wojciech Pacula(url below), it wasn't quite prepared for how well and closely he described the sound of the Thoress. At the right volume and with the right recordings, the following 2 paras really resonate with how I felt listening to the system with Thoress in place.

"It was fascinating how deep was the interaction between the instrument's box and the acoustics. It was an unusual harmony, air was vibrating, as if it was inseparable from the instrument itself - even though it was imaged precisely, without the blurring of its edges."

"It presents a great space, building it in the form of a "bubble", also around us. It energizes the air in the room with ease, including it in the created musical world."

The Thoress is really quite special in how it creates this 'bubble' of sound around the listener. Something that I have not experienced before in my own system with the Yamamoto or my other amps like Dynacos, MCcormack DNA1, audio note kit 1; and other more expensive systems I heard at shops.

It's a pity that I couldn't find more people sharing and talking this amp.

http://highfidelity.pl/@main-793&lang=en
 

christoph

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Several years I ago I used Apogee Studio Grand bi-amplified with Krell and ML. How you are using it?? Amplified with SE?? I can't belived!
I use either a 30 watt KR Audio VA350 SET or a 50 watt KR Audio Kronzilla SX SET for my Studio Grands.
I haven't tried the 30 watt Ayon Crossfire 3 SET though (yet).

I also used Musical Fidelity KW750 and Krell KSA100 MK2 (both SS) as well as Lamm M1.1 and Sphinx Audio PJ14 (both hybrid) on the Studio Grands but I prefer the SET Sound of my KR Audio SETs

Do you still have your Studio Grands?
I really love them :cool:
 
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morricab

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I use either a 30 watt KR Audio VA350 SET or a 50 watt KR Audio Kronzilla SX SET for my Studio Grands.

I also used Musical Fidelity KW750 and Krell KSA100 MK2 (both SS) as well as Lamm M1.1 and Sphinx Audio PJ14 (both hybrid) on the Studio Grands but I prefer the SET Sound of my KR Audio SETs

Do you still have your Studio Grands?
I really love them :cool:
Yep, planars and SETs can sound magical! I loved my SET amps with both ribbon and electrostats :D
 
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cjfrbw

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My Bohlender 75 inch midrange ribbons 300 hz-7 kHz are so efficient I can play 45 and 2a3 tubes for the first time in my main system. They sound lovely and uncompromised in that range at the efficiency of these ribbons, while the lower four octaves have the heavy lifting done by a Yamaha B2 VFET and subwoofers. It is the first time I have had ribbons efficient enough to do that. I can pick up the amp with one hand, and looking at the small tubes and the sound coming out of the speakers is a complete intuitive disconnect. The efficient ribbon makes me think I am getting the better of two worlds now: horn efficiency with ribbon performance.

Every audiophile needs to hear a 45 tube system with efficient setup at least once to recalibrate what amplification means. I have heard them at shows with the big horns. The sound is raw, but alluring, and makes you feel as close the signal as you can get. 45 tube upper midrange is dynamically open, splashy, and makes the upper midrange of even highly touted amps seem compressed and crumpled by comparison.

A jaw dropping performance from an ordinary 45 tube makes me wonder about the common audiophile promotion of toe stubbing monolithic amps weighing hundreds of pounds ‘because you need to rescue the elusive 120db micro transient, or your amplification is deficient’.

‘Rescue the micro transient’ attitude is also promoted by the audio *cough* critics *cough* salesmen, who try to make you believe that certain audio qualities can only be attained with hundreds of watts, with overhead of a thousand or so at least.

The ‘you can hear the hundreds of empty watts’ meme seems to be one of the few memes that is shared by both a segment of the subjectivist audio community as well as the hard core objectivist community.

I think it comes down to a wry statement that audiophiles ‘just like heavy stuff’.
 

morricab

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My Bohlender 75 inch midrange ribbons 300 hz-7 kHz are so efficient I can play 45 and 2a3 tubes for the first time in my main system. They sound lovely and uncompromised in that range at the efficiency of these ribbons, while the lower four octaves have the heavy lifting done by a Yamaha B2 VFET and subwoofers. It is the first time I have had ribbons efficient enough to do that. I can pick up the amp with one hand, and looking at the small tubes and the sound coming out of the speakers is a complete intuitive disconnect. The efficient ribbon makes me think I am getting the better of two worlds now: horn efficiency with ribbon performance.

Every audiophile needs to hear a 45 tube system with efficient setup at least once to recalibrate what amplification means. I have heard them at shows with the big horns. The sound is raw, but alluring, and makes you feel as close the signal as you can get. 45 tube upper midrange is dynamically open, splashy, and makes the upper midrange of even highly touted amps seem compressed and crumpled by comparison.

A jaw dropping performance from an ordinary 45 tube makes me wonder about the common audiophile promotion of toe stubbing monolithic amps weighing hundreds of pounds ‘because you need to rescue the elusive 120db micro transient, or your amplification is deficient’.

‘Rescue the micro transient’ attitude is also promoted by the audio *cough* critics *cough* salesmen, who try to make you believe that certain audio qualities can only be attained with hundreds of watts, with overhead of a thousand or so at least.

The ‘you can hear the hundreds of empty watts’ meme seems to be one of the few memes that is shared by both a segment of the subjectivist audio community as well as the hard core objectivist community.

I think it comes down to a wry statement that audiophiles ‘just like heavy stuff’.
You can drive the 87db/watt RD75 driver with 1.5 watt amp? The lowest I tried my RD28.1 drivers was 30 watt SET.
 

cjfrbw

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You can drive the 87db/watt RD75 driver with 1.5 watt amp? The lowest I tried my RD28.1 drivers was 30 watt SET.
Yes, when researching these ribbons all indications were that they were in the high 80's in efficiency. I bought these from a guy who got them on close out from the BG factory when they went out of business in Nevada. There is only so much information on the internet about the RD75. The fascia of these I have is similar to the fascia of the ribbons used in the Gryphon Pendragon, which is cited to be 89 db with a passive crossover @ 200 Hz or so. The passive crossover could knock off a couple of db of efficiency, but I think the ones I have are even more efficient than that.

The most I could glean was that when Bohlender went with Wisdom Audio, he intended a new, improved ribbon that would be easier to drive and would not need the notch filter for glare at 5 khz.

The pair I have on hand is reputedly NOS having been stored for a project that never came into being. It must be a more efficient model that was made later. It is VERY efficient in my room, and does not require a high current amp. I had to repair one of them to establish electrical contact back again.

They kept getting louder as they broke in and I had to keep dialing them down relative to the other frequency ranges. I am estimating the effective 'raw ribbon' efficiency at about 94 db, for whatever reason. That could be a combination of raw efficiency and it's line array dipole projection into the room. I presume the magnets must be stronger and this was just an unexpected bonus from an anonymous pair of these ribbons. I sit with them about 30 degrees off axis about 9 feet away. Room is 13.5x19 in main area, with high slanted ceiling and a dogleg on one side adding more space.

45/2a3 tube from a little amp made by an amp cobbler on ebay sounds great with both 45 and 2a3 using it in the active crossover range of 300 Hz to 7 Khz. That takes the burden off of it in the lower four octaves and the upper octave and a half. Even so, it would have to be efficient to work with 1.5 watts at all. 45 can even handle classical music torture test at high volume, and 2a3 seems to have ample headroom.

This 300 hz to 7 khz range is the major localize-able midrange, which is where the SET does it's best work.

The unexpected efficiency was a pleasant bonus. If somebody told me several months ago that I would have a broad midrange ribbon that would play loud and well with a 45 or 2a3 tube, I would have thought they were crazy.
 
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christoph

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Dante Choi

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I use either a 30 watt KR Audio VA350 SET or a 50 watt KR Audio Kronzilla SX SET for my Studio Grands.
I haven't tried the 30 watt Ayon Crossfire 3 SET though (yet).

I also used Musical Fidelity KW750 and Krell KSA100 MK2 (both SS) as well as Lamm M1.1 and Sphinx Audio PJ14 (both hybrid) on the Studio Grands but I prefer the SET Sound of my KR Audio SETs

Do you still have your Studio Grands?
I really love them :cool:
Sorry for my late reply. Already sold Apogee Grand. Now I am using WIlson Alexx and Tannoy Autograph with Silver Monitors. Congratulation for your system.
 
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cjfrbw

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Since I have this efficient BG 75 ribbon for the midrange 300Hz - 7Khz crossover points, and I have used flea powered amps to rather wondrous effect (45/2A3/300b), i was wondering what a SEP(single end pentode) would sound like.

Nelson Pass made an offhand comment that his SIT amps (SIT-1 and SIT-2) sounded nearly exactly like an EL34 single ended amp that he had (of course, this is after his SIT amps were already sold out, since you can get an EL34 single ended chassis with tube rectification for a couple hundred dollars on eBay and the SIT amps were 5k for single chassis and 10k for two mono blocks). He also said his SIT amps were the sound “of a single transistor clapping”, since the single SIT device operated for both voltage and current amplification in a single device to produce about 10 watts per channel single ended.

I didn’t want another large chassis, but this little mini watt amp seems to have been creating a ground swell for it’s great sound at modest cost. 3.5 watts using a tube called a ‘compactron’ which is a pentode driving a tetrode power tube in a single tube (sound of a single tube clapping), which is as simple as things get.

Gemtune APPJ PA1501A mini tube amplifier with 6AD10 tube (black)
Amazon.com: Gemtune APPJ PA1501A mini tube amplifier with 6AD10 tube (black): Electronics

Chinese made for budget market: repulsive, check.

Switching rather than linear power supply: abhorrent blasphemy, check

Tiny Japanese EL84 output transformers: obnoxious, possibly even evil, check

Flea power @ 3.5 watts per channel: laughable, check

Using it on 75 inch BG 75 ribbons for midrange from 300-7000 Hz crossovers: Idiotic, if not insane: check

With various Amazon incentives and credits, the amp was delivered with GE five star Compactron (I love that name) tubes for a grand total of $123 delivered.

How’s it sound? FANTASTIC!

I think Pass was right (at least about the concept of one device clapping).

How’s it sound compared to equally powerful 2A3? If the DHT is the master of musical grammar, then the SEP is the master of musical punctuation. SEP is perhaps slightly on the compressive side, whereas DHT is on the dynamic range expansive side. SEP is more energetic, with great transitions and just the suggestion of crunch, grind and snap (as you would expect from pentode) without losing detail or significant spatiality. Very cool sound, and this thing isn’t even broken in yet. It’s also quiet without any pentode tube rush or hiss that I can detect. It is definitely in the rotation of amps for this midrange ribbon. It has plenty of gain. I don’t even have it turned up all the way, and needs no other gain stage to fit right into the system. Above 95db efficiency likely required for reasonable performance.
lrbwmK4ZS7GlFs0LN%cusA_thumb_b34.jpg
Here it is sitting on top of the 50 watt Wavac.
 
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morricab

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Since I have this efficient BG 75 ribbon for the midrange 300Hz - 7Khz crossover points, and I have used flea powered amps to rather wondrous effect (45/2A3/300b), i was wondering what a SEP(single end pentode) would sound like.

Nelson Pass made an offhand comment that his SIT amps (SIT-1 and SIT-2) sounded nearly exactly like an EL34 single ended amp that he had (of course, this is after his SIT amps were already sold out, since you can get an EL34 single ended chassis with tube rectification for a couple hundred dollars on eBay and the SIT amps were 5k for single chassis and 10k for two mono blocks). He also said his SIT amps were the sound “of a single transistor clapping”, since the single SIT device operated for booth voltage and current amplification in a single device to produce about 10 watts per channel single ended.

I didn’t want another large chassis, but this little mini watt amp seems to have been creating a ground swell for it’s great sound at modest cost. 3.5 watts using a tube called a ‘compactron’ which is a pentode driving a tetrode power tube in a single tube (sound of a single tube clapping), which is as simple as things get.

Gemtune APPJ PA1501A mini tube amplifier with 6AD10 tube (black)
Amazon.com: Gemtune APPJ PA1501A mini tube amplifier with 6AD10 tube (black): Electronics

Chinese made for budget market: repulsive, check.

Switching rather than linear power supply: abhorrent blasphemy, check

Tiny Japanese EL84 output transformers: obnoxious, possibly even evil, check

Flea power @ 3.5 watts per channel: laughable, check

Using it on 75 inch BG 75 ribbons for midrange from 300-7000 Hz crossovers: Idiotic, if not insane: check

With various Amazon incentives and credits, the amp was delivered with GE five star Compactron (I love that name) tubes for a grand total of $123 delivered.

How’s it sound? FANTASTIC!

I think Pass was right (at least about the concept of one device clapping).

How’s it sound compared to equally powerful 2A3? If the DHT is the master of musical grammar, then the SEP is the master of musical punctuation. SEP is perhaps slightly on the compressive side, whereas DHT is on the dynamic range expansive side. SEP is more energetic, with great transitions and just the suggestion of crunch, grind and snap (as you would expect from pentode) without losing detail or significant spatiality. Very cool sound, and this thing isn’t even broken in yet. It’s also quiet without any pentode tube rush or hiss that I can detect. It is definitely in the rotation of amps for this midrange ribbon. It has plenty of gain. I don’t even have it turned up all the way, and needs no other gain stage to fit right into the system. Above 95db efficiency likely required for reasonable performance.
View attachment 60143
Here it is sitting on top of the 50 watt Wavac.
I have an 11 watt SEP from Mastersound, it is peppy and open but not the same level of natural tone as my AC Genus. No surprise give the design limits of both. Still a quite pleasant surprise for low (not as low as yours though) money.
 

dcc

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Any plans to tube roll?

Yes but not immediately.

When I auditioned several amps with the loudspeakers I had selected (Cube Audio Bliss C), the Line Magnetic was shining against the Octave V40 SE and the Luxman L-550 AX II. I had anyway selected the loudspeakers with a SET amp in mind. The comparative listening session just confirmed my initial choice.

I first need to finish the room where the secondary system will go and I am still waiting for the audio rack that will arrive in late January. In the coming days, I will test the secondary system in the main room against the main system.

Once I am fully acquainted with the sound in the room, I will consider some tube rolling.
 

adamaley

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Yes but not immediately.

When I auditioned several amps with the loudspeakers I had selected (Cube Audio Bliss C), the Line Magnetic was shining against the Octave V40 SE and the Luxman L-550 AX II. I had anyway selected the loudspeakers with a SET amp in mind. The comparative listening session just confirmed my initial choice.

I first need to finish the room where the secondary system will go and I am still waiting for the audio rack that will arrive in late January. In the coming days, I will test the secondary system in the main room against the main system.

Once I am fully acquainted with the sound in the room, I will consider some tube rolling.

You're in for a treat - tube rolling transforms the amp.
 

the sound of Tao

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I just got this little boy for my secondary system:

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.
 

cjfrbw

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I have an 11 watt SEP from Mastersound, it is peppy and open but not the same level of natural tone as my AC Genus. No surprise give the design limits of both. Still a quite pleasant surprise for low (not as low as yours though) money.
You know from scientific instrumentation that you can often get the first 90 percent economically, but the next 10 percent in precision and materials goes up in cost exponentially. The last couple of percent can really cost. Audio can be the same.

When the single ended 2A3 performed so well on these BG 75 ribbons, I had a bit of a disconnect that they were actually flea powered.

The bass panels on my Analysis Epsilon speakers perform as excellent full range drivers @ 87-89db efficiency or so, and any of my plus 20 watt class A amps drive them cleanly louder than I can stand.

I hooked up the 2A3 to them full range, and it was a dismal failure. I had to juice up the gain by 8db just to get minimal volume, and the sound shredded and fell apart with any suggestion of lower midrange or bass like a cheap console radio with a paper cone that had lost it's surround. The more restricted 300 to 7 Khz signal was a bit better because of lower energy demand, but still could clip and sounded dull and lifeless.

The same 2A3 on the efficient BG 75 @ 300 to 7Khz opens up wide, deep, airy, immaculate transients, layered etc. etc.

This little SEP sounds REALLY good in the midrange. It captures all the 'hairy caterpillars' of transient textures like grinds, bleets, slaps, hums, grits, buzzes, twangs, etc. in amplified instruments. Perhaps that is because many amplified instruments( and/or microphones), especially guitars, are already weaponized by pentodes and it takes a pentode to reveal a pentode?. Buckethead's various guitars all come through beautifully. The little SEP took a great leap in gain and smoothness after about 24 hours of burn in, which I attribute to cathode burn in. The sound stage also increased in width and depth.

I think this unanticipated adventure with flea powers shows that tubes still have unique and desirable properties that are as yet un-emulated by non-tube amps (and I really like my couple of solid state'ers).
 
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Exlibris

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You know from scientific instrumentation that you can often get the first 90 percent economically, but the next 10 percent in precision and materials goes up in cost exponentially. The last couple of percent can really cost. Audio can be the same.

When the single ended 2A3 performed so well on these BG 75 ribbons, I had a bit of a disconnect that they were actually flea powered.

The bass panels on my Analysis Epsilon speakers perform as excellent full range drivers @ 87-89db efficiency or so, and any of my plus 20 watt class A amps drive them cleanly louder than I can stand.

I hooked up the 2A3 to them full range, and it was a dismal failure. I had to juice up the gain by 8db just to get minimal volume, and the sound shredded and fell apart with any suggestion of lower midrange or bass like a cheap console radio with a paper cone that had lost it's surround. The more restricted 300 to 7 Khz signal was a bit better because of lower energy demand, but still could clip and sounded dull and lifeless.

The same 2A3 on the efficient BG 75 @ 300 to 7Khz opens up wide, deep, airy, immaculate transients, layered etc. etc.

This little SEP sounds REALLY good in the midrange. It captures all the 'hairy caterpillars' of transient textures like grinds, bleets, slaps, hums, grits, buzzes, twangs, etc. in amplified instruments. Perhaps that is because many amplified instruments( and/or microphones), especially guitars, are already weaponized by pentodes and it takes a pentode to reveal a pentode?. Buckethead's various guitars all come through beautifully. The little SEP took a great leap in gain and smoothness after about 24 hours of burn in, which I attribute to cathode burn in. The sound stage also increased in width and depth.

I think this unanticipated adventure with flea powers shows that tubes still have unique and desirable properties that are as yet un-emulated by non-tube amps (and I really like my couple of solid state'ers).
Are there powerful pentodes like the triodes (211, 845, 813, etc.)?
 

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