SE distortion

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:confused:
Are you trying to say that SE amps can't reproduce classic music?
I strongly disagree...

Paul

You can read whatever you want.
Did I say that?
Or that is that you understund.

Once in 1998 i went from Argentina to Miami to look for a lowther speaker (now i live on spain) And knew a man that sales this precious things. This man had many amps, all vacuum tubes, I remember the MC275 and more than twenty similar monsters. This amps full the living monster room but he mentioned that He had there in the "patio" one SE with WE300B, the transformers was builded on japan for a master winder experts, the iron maybe weight 10kg each, This man was maybe a little deaf but he said, that amp is waste. For curiosity I asked for connect it to the same musical program we were listening. I remember Harry Belafonte singing Calypso in a flea market got record. I listened that Mr. Belafonte was there in this room, singing for me. In this moment I recognized a miracle. In this moment I said to me: "I want this and i will spend the enough for get it"
But the time pass and many things happen and got this kind of amp. I listened SE and spend and read and project and listen. Now i say: I can listen classic music with them but Chamber music, tango, jazz, vocal, Soloists and specially music with no big headroom. When I need to listen Symphonic music I need at least biamp and pushpull nor odd neither even harmonics.
An Hifi man need at least five amps in the living room. Some day I awake in the morning and connect my SE, the next week I want to listen spaghetti and feel the needs of connect another taste. And connect my SE to Bruckner for a while I miss a real and alive music. But this is no here, and I miss it.
Maybe you have a SE. Maybe you paid a eye and the other half for it. And now you justify saying is the proper form to listen classic music. ;)
 
Fascinating!

Can you please point me to a reference that shows a measurement of this phenomenon? I would like to see the nonlinearity of the magnetization curve without DC bias.

Thanks!

Somehow I cannot believe that you, of all people, didnt know this...
I knew the theory, and cannot find a flaw in it, but at the same time I am not able to measure or detect any hysteresis based distortion in my Parafeed SE amps. And with parafeed and SE it should be obvious.

What am I missing? You have an explanation?

Paul
 
You can read whatever you want.
Did I say that?
Or that is that you understund.

Once in 1998 i went from Argentina to Miami to look for a lowther speaker (now i live on spain) And knew a man that sales this precious things. This man had many amps, all vacuum tubes, I remember the MC275 and more than twenty similar monsters. This amps full the living monster room but he mentioned that He had there in the "patio" one SE with WE300B, the transformers was builded on japan for a master winder experts, the iron maybe weight 10kg each, This man was maybe a little deaf but he said, that amp is waste. For curiosity I asked for connect it to the same musical program we were listening. I remember Harry Belafonte singing Calypso in a flea market got record. I listened that Mr. Belafonte was there in this room, singing for me. In this moment I recognized a miracle. In this moment I said to me: "I want this and i will spend the enough for get it"
But the time pass and many things happen and got this kind of amp. I listened SE and spend and read and project and listen. Now i say: I can listen classic music with them but Chamber music, tango, jazz, vocal, Soloists and specially music with no big headroom. When I need to listen Symphonic music I need at least biamp and pushpull nor odd neither even harmonics.
An Hifi man need at least five amps in the living room. Some day I awake in the morning and connect my SE, the next week I want to listen spaghetti and feel the needs of connect another taste. And connect my SE to Bruckner for a while I miss a real and alive music. But this is no here, and I miss it.
Maybe you have a SE. Maybe you paid a eye and the other half for it. And now you justify saying is the proper form to listen classic music. ;)

:) I have a SE indeed, but thats not the reason I gave the reply...
I really didnt understand your story, and I thought thats what you meant.

But if you mean that you should use a different amp for all kinds of music, I can understand that. But I also think, that how better the amp, the more "versatile" it gets.
There are SE amps suitable for symphonic. (and hardrock house metal and so on...)

Paul
 
Sorry for my poor English language, I tried to mean that I listen many amps SE, one of the best, and like them so much. In this moment I recognize the timbre of SE and fall in love with it. I mention it for express how I was impressive with SE. Maybe is redundant to say so much. And now I feel a different taste. Probably better because I listen much much music, Rock, jazz, classic, opera and chamber. All across of different equipment and combination of them, Bi triamp, Full range, etc. Horns and multispeakers systems. Some days I love the reproduction in the Solid state Arcam alpha 7 with the cheap and stupid sony loudspeaker I listen in my bedroom, them I going to my official place in the living room and find another whether.
Some days I like to listen many second and even harmonics and I use my SE, another days I want to listen sharp, edgy brillant and with more dynamic range.
Some days i change the feedback to my amp, the another day i put a little more or less, and I like it anyway.
Music across one electronic reproduction system is a subjective experience.
But the real music reproduction is alive.
I hope I could explain better;)
 
No problem:) I understand it a lot better now! I'm always wrestling with the same problem, my native language bleeding through my english...:D

Although I understand it, my wife would kill me before I could put even more amplifiers in the living room. Only thing to do is improve my main amp until it is good enough for all kinds of music!

Paul
 
An Hifi man need at least five amps in the living room.
Not necessarily. SE amp may have issues with producing punchy bass depending on its design and the speakers it's driving but that can be solved with 2 amps, not 5. Solution? Active bi-amp. Mid to high drivers with SE amp and low frequency driver with PP amp. Set up can be tricky but once the user gets over the learning curve, it's golden. Highly recommend it. :up:
 
Hi dady
Nice to see you around here.
Remove from your head the idea that the SE has only second harmonic distortion, look at what it says Pano in post # 5.

If what bothers you of the SE is the low damping factor, put it negative feedback.
I don't like feedback for "ideological reasons" : You can't correct in the past an event of the present, travel into the past is not posible.

If you don't like the subtlety of the 300B, go to a big boy like a 845, I like brute force because of the damping factor.
SE OPT are a real PITA, but not impossible.
I have a double C lamination, NOSS, and I'm preparing to winding say 7000 turns of the primary.

Best regards
Popilín
 
Hi Popilin, always is nice to each other to see people of my so faraway country, but specially you.
I remove the idea of the "only pairs" in SE. Norman Crowst talked about eighty one...
I agree with many of the builders and co-blogers but I listen music again every day, more than one hour. Is impossible to listen symphonic music for my brain and my tinnitus disease further in a theatre with orchestra. But many of this music listening are of symphonic one and I recognize the monster quantity of sound that our equipments build in a freeway form.
Multiamplification is the right sense. At least Biamp for avoid inter modulation that always sum to the rest of "chorizo".
I formerly declare that the liveness of SE give a "you are there" and I feel there and impressed but is not for all.
Music across an electronic device is a subjetive experience , some times I putt more negative feedback and feel more damping and wide sense and punchy bass but two days after I miss the liveness of no NFB.
 
Somehow I cannot believe that you, of all people, didnt know this...
I knew the theory, and cannot find a flaw in it, but at the same time I am not able to measure or detect any hysteresis based distortion in my Parafeed SE amps. And with parafeed and SE it should be obvious.

What am I missing? You have an explanation?

Paul

Magnetic hysteresis is based on the reversal of direction, not crossing some absolute zero magnetization level.

This is exactly borne out in Maxwells equations, specifically Faraday's law.

You should find magnetic hysteresis based distortion at very low signal levels, in both SE and PP output transformers.

I don't find evidence or theory for an additional source of distortion in PP output transformers due to "magnetic zero crossing". What I do see is a general change in permeability due to the SE magnetic gap and DC bias which changes the shape of the B-H curve overall.
 
Paul friend.
Hysteresis means delaying, is a phenomena that always happen because the magnetization of the core is not lineal and the demagnetization is delaying to, if you see the way of rise and the inverse they walk for different parts of the coordinates system and them describe a typical curve that delimiting an area. The more horizontal or vertical tendence depends of the permeability of the core. More force lines more vertical and "visceversa". The distortion produced for this phenomena became for its non linearity, If you inject a positive part of a sinusoid wave in a primary of a transformer a magnetic field rise there, that theoretically going to transfer to the secondary, but the magnetic field suffer an hysteresis (a delaying) And a part of the wave arrived to the secondary but late. Imagine this in going and returning 5000times for second. The hysteresis depend of the size in the grain and the orientation of the molecule in the core.
Sorry for my englpanish that I could understand of this phenomena.
 
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Hi Esteban,

My gut tells me that the hysteresis-distortion should be amplitude based, not time based. But I could be wrong.
I see it like this: in the time the field is reversing direction, until it is in the "straight" part again, coupling isnt ideal. so the amplitude is a little bit smaller as should be, and deformed. But how much influence I dont know; as I said to Michael, I have a parafeed SE with a air gapped transformer, and am unable to measure or "see" such events on the scope or distortion meter. Also it sound at least as good as the same transformers in a "normal" SE configuration.

Paul
 
If you have a parefed you don't need a gap in your transformer. You haven't DC there. You have not magnetization problem. Probably you waste some of the properties in have a gap, What transformer do you have? Maybe you can avoid the capacitor in serie and win a little with this measure. I read about hysteresis for confirm if I were wrong. Look at the the curves at the Popilin post http://www.diyaudio.com/forums/atta...80639d1336193341-se-distortion-hysteresis.gif is typical envelope of this phenomena. For watch this you need a couple of devices but I don't know exactly.
Avoid this problem completely is impossible. You need more big grains in the alloy but with this you lost some of the another advantages you got, Is a compromise solution between frecuency response, magnetization of the core, price, distortion, parasitic capacity, there are not perfect transformer. Why many persons protest against the vacuum tube amplifiers. Why they tried to develop OTLs? How much cost a Tango or a Tamura? Did them sound so different to the rest of well made one?
Some years ago I read Martin Colloms (I thinks is well write) He said that "you can measure amps that actually sound good more distorted than many amps that measure perfect. Why people continuate in listening with those amps with tubes if the technical development made a Solid State with not transformers that show undetectable distortion for our ears?" Is a subjective experience... Some times I like rock with punch and another day pop with mids. Some days i like strident sound with no NFB and another I feel dry music...
Best Regards
 
Hey, Esteban

I know I dont need a gap; I bought the transformers before I knew it would be a parafeed SE:D

I even asked here on DIYaudio if that would be a problem, but other than that it made the transformer a lot larger than needed, it should be OK, they said.
And thats what I found out too; it sound terrific.

The rest of your post is clear to me; but I think there is more to it then it seems.
I believe it should be measureable if an amplifier sounds good, but we keep on measuring the wrong things. THD doesnt say much, higher order distortion at 0.01% is more detectable then 0.1% 2nd harmonic, IMD is more important, and so on....
In the end our ears are the judge!

But regarding transformers: maybe you are right, and is the core material and the hysteresis and permeability very important for the sound and what makes a good or bad transformer.

Oh and you asked what transformer I had: it is from http://www.ae-europe.nl/uitgangstrafo_engels.htm

This one: C-core output transformer:

One step further in refinement is the output transformer with high quality c-core. For some time now we use cores with a lamination thickness of 0,05mm. This is rare in the fabrication of output transformers. But the quality is sublime. These cores have better quality and less losses. Therefor they can be build smaller then an EI-core transformer, without given in on for example a deep bass response. Of course they are winded in multipal sections. The frequency range is unprecedented large. These output transformers will be potted in a fine housing.



Paul
 
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Hi Dady
Nice to see you again.
Very clear your concepts, without wishing to offend you, you look like an electronics engineer, and I do not mean quacks, "opinionologyst" and critics by profession, but a good one !!!

IMO is far more simple than are thought, take a scope, a signal generator and any transformer, put a sinusoidal voltage at any winding, with the scope you can see a sinusoidal voltage, but what about the current? is not sinusoidal.
The effect is more noticeable the more you approach the working conditions of the amplifier (voltage, current, transformer)
Even more, with proper assembly, you can see the curve of the hysteresis loop on the scope.
I've seen many times in the lab, children watch with wonder the scope.
I can not believe that anyone, at least in this thread, what ever did.

Sinusoidal voltage and non-sinusoidal current means distortion, AFAIK.
I do not understand people who full with a lot of iron their amps.
Kondo San was so clever, he put only the indispensable.

Best regards
Popilín
 
Hi Popilin,

I am not a electronics engineer, neither am I a critic or opinionologyst; only a hobbyist.
But I am trying to learn from everyone, and help some people here and there.

Do I have it correct that you mean this:
Put a sinusoidal voltage on the primary of a transformer, put a 1 ohm resistor in series so I can measure and see the current(shape) on a scope, and put a resistor on the secondary so I can do the same there.

I will try this, and put results here; I am all for experimenting. Theory is nice, but seeing is believing.

Popilin, i'm not trying to offend you, but maybe you could show a little bit more respect for your fellow DIY-ists. We all have to discover or own thruth!:D
 
Hi pauldune
Forgive me if I offended you, it was not my intention, I don't mean you.

My story in the forum is that every time I say something with the best intentions, always I am fiercely attacked.

Do not know if I am or do not like my flag.
Dady know who they are quacks, "opinionologyst" and critics by profession.

Just when it appeared your post was to praise your transformers.
BTW, the assembly you use depends on signal generator, transformer, scope, etc. 1ohm looks too small, but make your own science.


Best regards
Johann
 
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Why is single ended distortion so high? In looking at tube data it seems SE distortion specs for tubes is much higher than for push pull. If that is the case why would anyone build an SE amp in the first place? Is it mostly 2nd order?


In typical SE design, most of the noise from the power supply is impressed on the primary of the output transformer. The quality of output transformer does come into play as DC idle current is present ( how well the transformer is gapped and winding interleave).

When I build an SE amp, I make my power supply have less than 5mV of noise at idle (no signal applied) measured from the output of the power supply.
 
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