No, it is the other way around.
http://www.diyaudio.com/forums/tubes-valves/250752-psu-choke-loftin-white-2a3-4.html#post4886833
Magnetic hysteresis is material dependent, it has nothing to do with a particular geometry, nevertheless, there is a trick to make the hysteresis loop thinner, i.e. more linear, the trick is called air gap...oops...we are talking about SE transformers.
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Nice scope. I worked at Tektronix (about 33 years). Nice output transformer.
I design and build both Push Pull and Single Ended Amplifiers.
And I enjoy listening to them. My designs are not perfect.
Some others also enjoy listening to my amps when we have an “Audio Crawl”. That is where about 15 club members split up into 3 groups, and serially go round-robin to 3 host homes (A, B, C) and listen to their audio systems. The hosts play some of their favorite recorded music, and the guests also bring CDs or records. Then we all gather afterwards at a restaurant for food and drink.
After 4 or 5 “Audio Crawls” over a couple of years time, we have enjoyed listening to each other’s audio system. Lots of fun. And we “discover” some music that we like but have not heard before.
Of course, an “Audio Crawl” has also been described as a gathering where someone brings a record or CD that brings the host’s audio system to its knees … like the 6 Hz cannon on the Telarc recording of Mr. T’s 1812 Overture. No, actually we are not that mean, and not that serious.
You may have an audio club in your area. Try getting them to have an “Audio “Crawl”.
(I stole the idea from the “Progressive Dinner” idea; and our club adopted it).
Now as to some items of amplifier theory and others.
Oh boy, that nasty air gap (I believe you were saying that with your tongue in your cheek).
No, not nasty. First of all, there are lots of very good and affordable SE transformers out there.
They do not have magnetic zero crossings (push pull transformers do).
SE Xformers have more bandwidth than my Pro Ac loudspeakers.
SE Xformers have lower distortion than my Pro Ac loudspeakers.
My Pro Ac loudspeakers have amorphous core crossover coils which do have magnetic
zero crossings. I did measure the loss of the woofer coil to be more than just the DCR of the wire. I need to do the same for the tweeter coil.
I am wanting to replace them with Air Core Inductors.
I once built a Push Pull amp, and then replaced the Push Pull output transformer with a pair of
SE transformers. It sounded very good, and very detailed. In that configuration, there were
no magnetic zero crossings.
If you have a “new idea” or favorite old idea, try it and see if you like it. The sound might surprise you.
I design and build both Push Pull and Single Ended Amplifiers.
And I enjoy listening to them. My designs are not perfect.
Some others also enjoy listening to my amps when we have an “Audio Crawl”. That is where about 15 club members split up into 3 groups, and serially go round-robin to 3 host homes (A, B, C) and listen to their audio systems. The hosts play some of their favorite recorded music, and the guests also bring CDs or records. Then we all gather afterwards at a restaurant for food and drink.
After 4 or 5 “Audio Crawls” over a couple of years time, we have enjoyed listening to each other’s audio system. Lots of fun. And we “discover” some music that we like but have not heard before.
Of course, an “Audio Crawl” has also been described as a gathering where someone brings a record or CD that brings the host’s audio system to its knees … like the 6 Hz cannon on the Telarc recording of Mr. T’s 1812 Overture. No, actually we are not that mean, and not that serious.
You may have an audio club in your area. Try getting them to have an “Audio “Crawl”.
(I stole the idea from the “Progressive Dinner” idea; and our club adopted it).
Now as to some items of amplifier theory and others.
Oh boy, that nasty air gap (I believe you were saying that with your tongue in your cheek).
No, not nasty. First of all, there are lots of very good and affordable SE transformers out there.
They do not have magnetic zero crossings (push pull transformers do).
SE Xformers have more bandwidth than my Pro Ac loudspeakers.
SE Xformers have lower distortion than my Pro Ac loudspeakers.
My Pro Ac loudspeakers have amorphous core crossover coils which do have magnetic
zero crossings. I did measure the loss of the woofer coil to be more than just the DCR of the wire. I need to do the same for the tweeter coil.
I am wanting to replace them with Air Core Inductors.
I once built a Push Pull amp, and then replaced the Push Pull output transformer with a pair of
SE transformers. It sounded very good, and very detailed. In that configuration, there were
no magnetic zero crossings.
If you have a “new idea” or favorite old idea, try it and see if you like it. The sound might surprise you.
Yes, very nice isn't it? Unfortunately they are not mine, I took the picture from the web.
Me too, and I design and build my own transformers too.
That's the key, you got it.
To see correctly the inter-modulation effects you need at least a 192kbps 24bit ADC which will show you the artifacts of feedback.
This scope is useless to get anywhere at optimizing any amplifier which has under arbitrary 0.5% distortion. Tecktronics are cheap junk if you want my own appreciation of changing them in instrumentation where they always break and are unreliable.
and yes, if you check math formula as you increase the perimeter of the transformer mass the hysteresis curve grows. It is more than only material dependent.
Solid state amplifiers are the best for micro-details. S.e.t. are claimed to be good at it but people confuse harmonics with micro-details. Again it is only personal experience.
EvenHarmonics you can believe whatever you want. I owned an expensive 845 s.e.t. amplifiers for a year and listend to it extensively and with some parts modification on all kinds of speakers. Micro-details where lacking because of the type of amplifier.
You cannot have micro-details in a soup of distortion and harmonics and a passive power supply, it is impossible... Micro-details are the first things gone in a poor amplification or poor audio system. You can hear micro-details when the sound is clear and clean and true to the source. S.e.t give you a romanticized version of the music. It is good for old opera recordings, old jazz records and background music.
s.e.t. distort so much that you can take the signal from a good solid state amplifier, feed it back into a solid state pre amp, back into the integrated s.e.t and you cannot hear any difference.
This scope is useless to get anywhere at optimizing any amplifier which has under arbitrary 0.5% distortion. Tecktronics are cheap junk if you want my own appreciation of changing them in instrumentation where they always break and are unreliable.
and yes, if you check math formula as you increase the perimeter of the transformer mass the hysteresis curve grows. It is more than only material dependent.
Solid state amplifiers are the best for micro-details. S.e.t. are claimed to be good at it but people confuse harmonics with micro-details. Again it is only personal experience.
EvenHarmonics you can believe whatever you want. I owned an expensive 845 s.e.t. amplifiers for a year and listend to it extensively and with some parts modification on all kinds of speakers. Micro-details where lacking because of the type of amplifier.
You cannot have micro-details in a soup of distortion and harmonics and a passive power supply, it is impossible... Micro-details are the first things gone in a poor amplification or poor audio system. You can hear micro-details when the sound is clear and clean and true to the source. S.e.t give you a romanticized version of the music. It is good for old opera recordings, old jazz records and background music.
s.e.t. distort so much that you can take the signal from a good solid state amplifier, feed it back into a solid state pre amp, back into the integrated s.e.t and you cannot hear any difference.
From simple equations to make transformers
Np = (Uac x 10⁸) / [√2 π fo S Bac(max)]
Rearranging terms
Bac(max) = (Uac x 10⁸) / [√2 π fo S Np]
Supposing the same magnetic material, for a bigger core, S will be bigger, and then Bac(max) is reduced, it follows that magnetic hysteresis curve B(H) is reduced too.
It is more than only material dependent, it is field dependent too.
Just because you had one bad experience you cannot jump to general conclusions. That's a typical mistake of people seeking for reassurance and immediate results, not really interested into experimenting and understanding.
In fact you seem to be a bit confused on how a transformer works.
If your 845 amplifier was bad it doesn't mean that all 845 amplifiers, or more in general SET amplifiers, are the same. Actually as these more often don't use feedback and are very sensitive to power supply quality there are large variations in performance. Another typical mistake is not considering how they work. A speaker that has been designed for solid state amps might not be good at all for a tube amp. And even if designed for it a speaker can generate much more easily artificial micro-details than a SET amplifier. Let's not speak of other things that generate more artificial micro-details that are not present on the recording and are very common among audiophiles. Spikes, for example, under every piece of equipment. That's probably the worst accessory ever introduced in HiFi!
Anyway the same impossibility of generalisation is true for any kind of amplifier.
That's true but the artificial micro-details I was writing about are generated by vibrations which depend on the their construction and the way the speakers are coupled to the "external world". Spikes under speakers are the best micro-details generators!
Glad that you wrote this. "Thd opinion wars" should include whole audio chain. Probably some winners, would be losers overnight.
I happened to find this interesting thread, and I'm surprised to see OP is me. I completely forgot about this thread.
After 4 years, I'm wondering the same thing again. I'm currently building a large choke loaded SS SE amp and it has LF THD bump, which was not really my intention, but it would have been the result of my subconsciousness...
I now have Hypex nCore, and it is super duper clean and detailed. I don't have any reason to make another amp if I'm completely happy with Hypex. I'm looking forward to comparing Hypex vs my own design.
https://www.diyaudio.com/forums/pass-labs/357180-sit-50w-single-amp-beta-4.html#post6296943
After 4 years, I'm wondering the same thing again. I'm currently building a large choke loaded SS SE amp and it has LF THD bump, which was not really my intention, but it would have been the result of my subconsciousness...
I now have Hypex nCore, and it is super duper clean and detailed. I don't have any reason to make another amp if I'm completely happy with Hypex. I'm looking forward to comparing Hypex vs my own design.
https://www.diyaudio.com/forums/pass-labs/357180-sit-50w-single-amp-beta-4.html#post6296943
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