SET amp owners thread

[bonzo75]

To pass judgement on SETs after listening to them on apogees is like passing judgement on Indian food after trying it in Brick lane, London

 

[awsmone]

OCD Mikey has produced a series of vids with the NAT triode amp with big ribbon panels

 

[awsmone]

 

[spiritofmusic]

Marc did you hear the 60 or the 120 watts on the analysis?

120W I believe...that's Transmitter rating.

 

[spiritofmusic]

To pass judgement on SETs after listening to them on apogees is like passing judgement on Indian food after trying it in Brick lane, London

I always told those guys my last meal at the rival next door was just the pits.

 

[marslo]

A fraught subject of controversy, so I wouldn't state anything outside of personal preferences.

In that context, I would say it makes it better. The power proposition is better as stated, because bypassing a passive crossover automatically makes for better power distribution to the speaker elements. You also get the 'direct report' over the selected frequency range from the amp without passive crossover elements.

Power is precious with most SET amps, and, of course, they might never work well on truly current hungry speakers, but they worked great with the Apogee Stage (and the Analysis Epsilon that I presently own).

SET amps also have most of their distortion in the lower frequencies, so using one on the midband from 200 Hz to upper midrange can give you the 'magic' without the problems of relying on the SET for bass.

I currently use solid state amps for the lower three and a half octaves and SET for the broader midrange, and the effect is magical.

A benefit of passive crossovers could be that they make the sound more uniform across the entire bandwidth through some kind of averaging process, but that single feature doesn't really sell me in exchange for the loss of efficiency.

I will now cover my head to get stomped by enraged passive crossover fans.

This is exactly the way my Duo Mezzo XD work with Crossfire SET , I adjusted the crossover at 220 Hz with -24 or -12 dB slope, depending on the preset of the DSP, the built-in amps of the subwoofer satelites are 2x500 W class D.
Funny thing - bass reproduction changes with different external amps which should theoretically influence only the bandwith above 220 Hz.

 

[morricab]

To pass judgement on SETs after listening to them on apogees is like passing judgement on Indian food after trying it in Brick lane, London

It should have favored the higher powered PP amp... it didn’t. That said this Apogee was an easy , flat 6 ohm impedance and not as insensitive as early Apogees.

 

[Tbzc]

I was a bit irritated by spiritofmusic’s comment that NAT Transmitter was a bit glassy. So I reconnected today mine and all I can say is: not at all. At least in my system. Very natural tone. Lots of SET qualities I easily recognize since I have owned 2 SETs and 1 PSET. Certainly less dark than VTL, I would say airy, but not thin or bright. Not at all. Still warm sound. Also good bass but presented a bit different than VTL which also presents stage less forward. But I do remember that it made a hughe improvement when I changed 6n6 tube to 6h30. For me, much better. Although I have read somewhere that 6n6 is smoother. In my system on contrary.

And I would also say that SET sound is not an unambiguous description of sound. It differs how the concept is implemented and which tubes are used. I have heard SET amps which are less natural - more glassy - than Transimitter. So, for me, Transmitter is much closer to my perception of SET sound ideal than some other SET amps I have heard.

 

[morricab]

To pass judgement on SETs after listening to them on apogees is like passing judgement on Indian food after trying it in Brick lane, London

Nonsense

 

[spiritofmusic]

Tbzc, no need to be irritated by my comment. Tbh, it was on a spkr I think isn't suited to it. I've also heard it on more forgiving box spkrs and it was way more organic.

Maybe another example of triodes-spkrs being the critical assessment, not just triodes on their own.

 

[bonzo75]

Agreed, if everything is done right, including the recordings. But a good deal of equipment is voiced for a preference. Classic tube sound is mid forward, or rather treble/bass stepped back, or at least treble recessed, which gives the impression of immediacy as the reflection/ambient cues are diminished. My VAC amp is somewhat classic in this regard. As such it is a situational role player, but a pleasant one. My LTA Ultralinear is ruler flat, fast, resolved. It presents as somewhat recessed as it was voiced for high efficiency speakers. I'm looking for one amp that combines the best virtues of both, along with the grunt of my old Pass amp. Three amps in one. Shouldn't be too hard to come up with, right?

My Lampi GG1 was rather forward, the GG2 iteration somewhat less forward as the HF extension was better. The Pacific I'd say is a little forward. All tube set dependent. I found it curious that you preferred your GG1 when Classical/Symphonic is your preference. But yours was set up differently - caps and tubes, engine?

I don't listen to classical much, but when I do, it's center row L, in the hall, not at home.

Forgot to mention here. When classic tube sound with an amp is mid forward, bass and treble stepped back, it is a problem with the transformer usually, or possibly something in the circuit, or under driven speaker. One of the reasons that 300b amps sound mid centric is that they don't have sufficient transformer oomph. If you get sub 10 watts 300b amp with a good transformer designed by someone who knows how, it will give complete linearity. As will 2 watt tubes if they drive 110 db straight 8 ohm impedance speakers

 

[cjfrbw]

One more for the road:
Clarinet Thing Echoes of Harlem Agony Pipes and Misery Sticks
6b4g amplifier tubes @ 4 watts BG 75 ribbons 300Hz-7Khz, digital 360kps FLAC( Svetlana DHT instead of Sylvania 6b5g indirectly heated triode)

digital instead of vinyl so no clicks or pops

 

[denimhunter]

Forgot to mention here. When classic tube sound with an amp is mid forward, bass and treble stepped back, it is a problem with the transformer usually, or possibly something in the circuit, or under driven speaker. One of the reasons that 300b amps sound mid centric is that they don't have sufficient transformer oomph. If you get sub 10 watts 300b amp with a good transformer designed by someone who knows how, it will give complete linearity. As will 2 watt tubes if they drive 110 db straight 8 ohm impedance speakers

So true but not often understood. With single ended amps, good transformer is crucial.

 

[spiritofmusic]

DH, it's a big reason Nat triodes sound so good. Twin traffos per mono...BIG Iron!

 

[bonzo75]

One more for the road:
Clarinet Thing Echoes of Harlem Agony Pipes and Misery Sticks
6b4g amplifier tubes @ 4 watts BG 75 ribbons 300Hz-7Khz, digital 360kps FLAC( Svetlana DHT instead of Sylvania 6b5g indirectly heated triode)

digital instead of vinyl so no clicks or pops

Can you do some with the mobile in the sweet spot? It makes a difference where you keep the mobile

 

[morricab]

Forgot to mention here. When classic tube sound with an amp is mid forward, bass and treble stepped back, it is a problem with the transformer usually, or possibly something in the circuit, or under driven speaker. One of the reasons that 300b amps sound mid centric is that they don't have sufficient transformer oomph. If you get sub 10 watts 300b amp with a good transformer designed by someone who knows how, it will give complete linearity. As will 2 watt tubes if they drive 110 db straight 8 ohm impedance speakers

Poor transformers, typically they are too small for SET, leads to high distortion in the bass. This has an impact on both the bass (sounds flabby and weak) and the midrange, which gets thick and less transparent. People used to PP amps will not realize how much bigger an output transformer needs to be for a SET of much lower power. Winding is also then critical as it impacts clarity and HF extension. Core material and geometry are interesting and impact the sound quite strongly as well. It is more art than science.

 

[Rob181]

Poor transformers, typically they are too small for SET, leads to high distortion in the bass. It is more art than science.

No it is both & why I have some sensational transformers...

 

[bonzo75]

No it is both & why I have some sensational transformers...

Which ones do you have?

 

[Rob181]

Just one example I bought - No 1 on the hit parade

 

[bonzo75]

Interesting, 5 digit tango. What's the difference with the tamura