What do measurements say about SET’s

[Rensselaer]

A 211-based SET Ongaku tribute from Uesugi Ken (Otomon Laboratory, Japan) that I recently commissioned is finished and will be shipped soon. He sent me the following measurements:

frequency response: 16Hz-45KHz (22 watts/8ohm)
hum level: 0.2mV
THD: 5% at 22W

I am requesting advice from the experts out there. I hear that SET’s sound great because the lack distortion in the upper odd-order harmonics. Some say the distortion makes them sound good, while still others say they sound good despite the distortion.

What do these measurements tell you? To me, the frequency response seems to be very good (however my speakers can’t go that low, and I can’t hear that high), but what about the THD and hum levels, are they acceptable?

 

[Gregm]

The primary objective of that amp is to help you listen to music, so the key question is: do you enjoy the music? If you do, end of story!

Coming to the question about the measurements you posted, no - any well-designed SS will measure far better in the values you have posted above. It remains to be seen how important these values are for your musical enjoyment!

Now, the actual measurements: the FR looks good for an SET (v. good even!), the noise is above average, the THD par for the course.(Again: for an SET. ) The output power (22W) is excellent and allows you to drive a great many speakers out there (mine included).

I for one don't think (even order) distortion makes the amp sound "better" at all; it would probably sound better without it - but you can't have a 211 SET with 0 distortion AND no feedback, and if you're to have distortion it might as well be low order even harmonics...

Presumably the amp sounds good despite the high level of distortion, etc, and that's why people choose to use SETs yourself included!

 

[Rensselaer]

4212 tube amplifier

I preferred the sound of his 4212 tube amps, but can you even find NOS 4212 valves anymore?

 

[Rensselaer]

My amp playing in builders system, not yet mine.
I should have entered this before the above.

 

[DasguteOhr]

My amp playing in builders system, not yet mine.
I should have entered this before the above.

Wireless Speaker..joke.nice amp

 

[Rensselaer]

Wireless Speaker..joke.nice amp

Yea, I already asked, two vids; the sound from one attached to the picture on the other.

 

[Audiohertz2]

A 211-based SET Ongaku tribute from Uesugi Ken (Otomon Laboratory, Japan) that I recently commissioned is finished and will be shipped soon. He sent me the following measurements:

frequency response: 16Hz-45KHz (22 watts/8ohm)
hum level: 0.2mV
THD: 5% at 22W

I am requesting advice from the experts out there. I hear that SET’s sound great because the lack distortion in the upper odd-order harmonics. Some say the distortion makes them sound good, while still others say they sound good despite the distortion.

What do these measurements tell you? To me, the frequency response seems to be very good (however my speakers can’t go that low, and I can’t hear that high), but what about the THD and hum levels, are they acceptable?

Well for starters you need a speaker with a zmin of 8ohm , best when talking SET is distortion numbers @1W , your speakers should be sensitive enuff as to not exceed 1 watt for normal Din ..

So mW levels to 1watt is what you are really interested in when discussing distortion numbers .


Regards

 

[Rensselaer]

Well for starters you need a speaker with a zmin of 8ohm , best when talking SET is distortion numbers @1W , your speakers should be sensitive enuff as to not exceed 1 watt for normal Din ..

So mW levels to 1watt is what you are really interested in when discussing distortion numbers .


Regards

0.3 mW at one watt.

 

[Rensselaer]

0.3 mW at one watt.

Sorry, that’s 0.3% at one watt

 

[Audiohertz2]

Ok those are the numbers you are interested in not the 5% quote to sound powerful . As you can see its a low distortion design in the mW level not high ..


Regards

 

[godofwealth]

I think the only real use for SETs is driving highly efficient horns like my Klipsch La Scalas (105 dB rated efficiency). In such an ideal setting, and considering that my normal average playback levels are in the mid 70 dB with peaks maybe going 10-20 dB, I think the distortion at 1 watt rating matters very little, not to mention the rating at the full output of this Ongaku SET (22 watts). I’d like to see measurements in the tens to hundreds of milliwatts. That’s all the range any of my SETs are likely to produce. I hear no distortion from any of my SETs. The really important measurement for a SET is noise. You’d be surprised how many solid state amplifiers sound very noisy when playing into my La Scalas. Even pentode amplifiers sound too noisy. A well designed SET should be absolutely quiet. It’s hard to make amplifiers that are quiet into a 105 dB efficient loudspeaker. Even turn on or turn off transients can be loud. When you turn on this Ongaku, how quiet is it? It should come on with no noise of any kind and turn off just as gracefully.

 

[sparkie]

am requesting advice from the experts out there. I hear that SET’s sound great because the lack distortion in the upper odd-order harmonics. Some say the distortion makes them sound good, while still others say they sound good despite the distortion.

Distortion meters have little significance in tube amps because they mistake their harmonic reproductions as distortion.
The more important figure would be the hum and noise output voltage (200uV or 0.2mV) at rated output.
so:
V=√(P*R)=√(22*8)=√176=13.266499161V
So at 13.266499V, 0.0002V of that is noise and hum. which is 0.000000005 W

Has a total of signal to noise ratio of 94.24db.

Which would be very good for an amp.

 

[sparkie]

My amp playing in builders system, not yet mine.
I should have entered this before the above.

The video doesn't have the good audio quality. That is why you tube is a bad platform to compare anything. That is why a lot of capacitor comparison videos are bad.

 

[morricab]

A 211-based SET Ongaku tribute from Uesugi Ken (Otomon Laboratory, Japan) that I recently commissioned is finished and will be shipped soon. He sent me the following measurements:

frequency response: 16Hz-45KHz (22 watts/8ohm)
hum level: 0.2mV
THD: 5% at 22W

I am requesting advice from the experts out there. I hear that SET’s sound great because the lack distortion in the upper odd-order harmonics. Some say the distortion makes them sound good, while still others say they sound good despite the distortion.

What do these measurements tell you? To me, the frequency response seems to be very good (however my speakers can’t go that low, and I can’t hear that high), but what about the THD and hum levels, are they acceptable?

Nothing until I see FFT spectra at low, middle and high frequencies, distortion vs. power, power supply noise, IMD spectra and distortion vs. frequency at the very least. Ideally, FFT at various power levels as well to see where the high order distortion starts to climb faster than the low order products.

 

[godofwealth]

I always find it curious that audiophiles obsess over distortion measurements when they are largely immaterial (e.g., DACs, preamps, amps), and almost never worry about them when it matters a great deal (e.g., speakers or rooms).

The greatest source of non linearity in any hifi system are the loudspeakers and your listening room. The room’s distortion dwarfs anything else by orders of magnitude. Measure a loudspeaker on axis and repeat for different locations in a room with varying degrees off the main axis. The result can be many decibels different. Loudspeakers sound utterly different as you walk around a room.

Every WBF member should watch a few of the renowned lectures on acoustics by MIT professor Amar Gopal Bose (yes, the same guy who founded the Bose company and left all his money to MIT when he passed away). He was considered by many undergraduates as one of the best lecturers at that famous institution.

InfiniteMIT | Amar G. Bose: 6.312 Lecture 01

The InfiniteMIT site is a collection of videos that create a vivid portrait of an institution that is continually changing the way we live and work. Interviews with legendary change-makers, historic footage from the MIT Museum collection, unforgettable lectures, commencement speeches, and symposia.

infinite.mit.edu

In one of his brilliant demonstrations he shows that a recording of a loudspeaker played back on the same loudspeaker quickly turns to complete noise if repeated just a few times. In contrast, you could hook up 30 SET amps, one into the next and assuming you set the levels right, the final output would not sound very different. In short, rooms distort far more than any SET ever designed.

Peter Walker who designed Quad electrostatics understood that and spent 20 years designing the Quad 63 to get rid of the problems that rooms pose. No one has yet to solve this problem, but he came pretty close. It’s stunning how a uniform a Quad 63 sounds as you walk around the room. Its sound barely changes. A brilliant masterpiece designed 60 years ago. Still the reference in many respects.

 

[morricab]

I always find it curious that audiophiles obsess over distortion measurements when they are largely immaterial (e.g., DACs, preamps, amps), and almost never worry about them when it matters a great deal (e.g., speakers or rooms).

The greatest source of non linearity in any hifi system are the loudspeakers and your listening room. The room’s distortion dwarfs anything else by orders of magnitude. Measure a loudspeaker on axis and repeat for different locations in a room with varying degrees off the main axis. The result can be many decibels different. Loudspeakers sound utterly different as you walk around a room.

Every WBF member should watch a few of the renowned lectures on acoustics by MIT professor Amar Gopal Bose (yes, the same guy who founded the Bose company and left all his money to MIT when he passed away). He was considered by many undergraduates as one of the best lecturers at that famous institution.

InfiniteMIT | Amar G. Bose: 6.312 Lecture 01

The InfiniteMIT site is a collection of videos that create a vivid portrait of an institution that is continually changing the way we live and work. Interviews with legendary change-makers, historic footage from the MIT Museum collection, unforgettable lectures, commencement speeches, and symposia.

infinite.mit.edu

In one of his brilliant demonstrations he shows that a recording of a loudspeaker played back on the same loudspeaker quickly turns to complete noise if repeated just a few times. In contrast, you could hook up 30 SET amps, one into the next and assuming you set the levels right, the final output would not sound very different. In short, rooms distort far more than any SET ever designed.

Peter Walker who designed Quad electrostatics understood that and spent 20 years designing the Quad 63 to get rid of the problems that rooms pose. No one has yet to solve this problem, but he came pretty close. It’s stunning how a uniform a Quad 63 sounds as you walk around the room. Its sound barely changes. A brilliant masterpiece designed 60 years ago. Still the reference in many respects.

What’s your point actually?

 

[Holmz]

A 211-based SET Ongaku tribute from Uesugi Ken (Otomon Laboratory, Japan) that I recently commissioned is finished and will be shipped soon. He sent me the following measurements:

frequency response: 16Hz-45KHz (22 watts/8ohm)
hum level: 0.2mV
THD: 5% at 22W

^That^ says little without a spectrum of the distortion, or the harmonic content.
understanding it is good, but if you like it, then maybe just enjoy it?

I am requesting advice from the experts out there. I hear that SET’s sound great because the lack distortion in the upper odd-order harmonics. Some say the distortion makes them sound good, while still others say they sound good despite the distortion.

Some 2nd and 4rd order distortion is usually perceived as a worthwhile.
Of course if you want “High Fidelity” then maybe o distortion is better.
But tube amps usually sound good.

What do these measurements tell you? To me, the frequency response seems to be very good (however my speakers can’t go that low, and I can’t hear that high), but what about the THD and hum levels, are they acceptable?

I would suggest getting a sub, and I high pass filtering the signal that goes into the SET.
That should help immensely.

 

[Audiohertz2]

If you take the sound of your favorite SET amp and drive it into the input of a low distortion SS amp , it will sound exactly like the SET but with power ...

A TF will confirm what you hear ...!

 

[morricab]

If you take the sound of your favorite SET amp and drive it into the input of a low distortion SS amp , it will sound exactly like the SET but with power ...

A TF will confirm what you hear ...!

You’ve done this? Musical fidelity had amp boosters called superchargers that claimed the same thing…funny thing…no one uses them…

 

[Superfi]

https://6moons.com/audioreviews/firstwatt6/f4.html

Another one. It's power buffer. Great amp, friend is using with pre with plenty of gain, didn't have opportunity to try with SET.