It's the real elliptical load, regardless of parafeed or not, instead of the usual loadlines people like to draw to find best primary impedance. Phase rotation in LC coupling 2x faster than just LR. That's bad for SE output stage, just look a anode curves a put an ellipse on them and see how easy you can stay in the linear area...no maths needed to see why.
Much higher frequency what? Have you got any experience with this or just reading?
Good SE transformers show no distortion increase above 30Hz. Want an affordable commercial example? Lundahl. That's perfect for use with music.
Even cheaper SE transformers like Edcor are PERFECT in this respect at least from 40Hz....that's not high frequency at all. Instead a lot of parafeed have worse phase rotation a those frequencies if start use caps as small as possible to avoid other tradeoffs. The blanket is always too short....
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Oh, you're talking about the speaker load, not the components inside the amp.
Yes, I would rather have a decent 50H plate choke and a 5K parallel feed output transformer for use with a #45 than any series feed iron Lundahl sells. The less steep the ellipse is, the better the LF performance on a real world load. Parallel feed gives you more control over that, and if you know a great deal about the parameter of the speaker itself, you can make adjust the parallel feed cap accordingly.
Also parallel feed costs more than series feed when all other factors are equal. Having purchased nearly identical series feed/parallel feed iron sets from a couple of vendors, this has always been the case for me.
Yes, I would rather have a decent 50H plate choke and a 5K parallel feed output transformer for use with a #45 than any series feed iron Lundahl sells. The less steep the ellipse is, the better the LF performance on a real world load. Parallel feed gives you more control over that, and if you know a great deal about the parameter of the speaker itself, you can make adjust the parallel feed cap accordingly.
Also parallel feed costs more than series feed when all other factors are equal. Having purchased nearly identical series feed/parallel feed iron sets from a couple of vendors, this has always been the case for me.
I've heard top notch parafeed design amps, and I use them in combination with some of the best "normal" output tube transformers.
I could not easily say whats best, because both can be breathtakingly good.
Btw, can someone recommend an excellent good anode choke manufacturer? I need such a 50H/100H anode choke, preferred sectioned chamber wound.
I could not easily say whats best, because both can be breathtakingly good.
Btw, can someone recommend an excellent good anode choke manufacturer? I need such a 50H/100H anode choke, preferred sectioned chamber wound.
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No. I am talking about the load on the power tube. Everything you put will have his part, capacitor included.
Really? I don't think so if do not compromise on other things....2 posts ago you were already convinced that 3 uF cap is much better than 100....
Blanket is always short. You improve on something at expense of something else and because your circuit is more complicated you will never be able to get the spider out of his hole....
I repeat that if it were really better it would become popular but it has not. Not even for quality purpose, just to make more money...not even that!
I am not really sure that's a rule....
I said I would rather shop for a premium 3uF cap rather than a premium 100uF cap considering that they are both very much in the signal path in series feed vs. parallel feed.
Parallel feed is definitely reserved for those who understand how to work with it, are willing to pay for it, and who are willing to answer the "why is your iron so small" question from customers endlessly. Yes, the reason I believe it's not popular is purely a cosmetic one. Parallel feed iron just doesn't have the look that people are going for. There's nothing dinkier looking than the old Magnequest 2.5K 2A3 parallel feed OT.
Parallel feed is definitely reserved for those who understand how to work with it, are willing to pay for it, and who are willing to answer the "why is your iron so small" question from customers endlessly. Yes, the reason I believe it's not popular is purely a cosmetic one. Parallel feed iron just doesn't have the look that people are going for. There's nothing dinkier looking than the old Magnequest 2.5K 2A3 parallel feed OT.
Discussions need to be technical otherwise it becomes all hot air.
I do not produce anything. I only design some transformers for myself and my friends but also use several good commercial transformers.
I am just saying what I think based on my experience with parafeed too. It's not based on sympathy, empathy or anything similar....
What you do is not my business. I know a lot of people who live in a "barrack" and go around in expensive cars....
And please don't tell me what I understand just because I made you notice that 3 uF is a BIG cap falling in higher loss class. The size of a transformer core instead has no negatives over a smaller one, within reasonable limits, if one can design a good transformer.
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Flatter what? Measure the phase and see....and if you insist I doubt you have ever used a good transformer which is not just the brand and the model but the right transformer for that application.
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>>While I was there, Matt played my (5K) amp through his top of the line system. The sound was just shocking. Honestly, most live concerts I've been to don't sound nearly as good. It was several levels above what I've heard before from recorded music. There was this presence and life that was just spell-binding. The attack of instruments was shocking. Really, recorded music has never demanded that I pay attention to it in the same way before.
We listened to Cannonball Adderley (with Miles Davis)'s Something Else. I felt like I was hearing them play their instruments for the first time. Their individual character really came through like I had never seen it before. Similarly, when we played a copy of Ellington's Masterpieces. I felt like I heard a recorded piano right for the first time, ever (and had never really realized what I was missing before). And when Ellington wanted the players to come in with force, you were jolted out of your seat.
>>
Tube-preamp: Parafeed design.
That counts zero for me. If we have to really look at how people listen to music in their homes with big issues regarding room acoustics only it's just opening a can of worms....
You can't know the circumstances, but this is a private review in an audio forum about a listening session that was done in an acoustically optimized audio dealers room. This may have helped a lot to let this happening.
Your findings are highly subjective and I'm very sure that you haven't even get in touch with the high end of those parafeed tube amp designs.
Their not easy to know and find, they are rare and they are exclusive and expensive. Some of them may not have been auditionable for public since ages. Some are actual designs.
The youth quickly finished with the word difficult to handle like a knife's edge; She takes cheekily from her hot head the measure of things that only judge themselves.
Wallensteins Tod II, 2. (Wallenstein)
Your findings are highly subjective and I'm very sure that you haven't even get in touch with the high end of those parafeed tube amp designs.
Their not easy to know and find, they are rare and they are exclusive and expensive. Some of them may not have been auditionable for public since ages. Some are actual designs.
The youth quickly finished with the word difficult to handle like a knife's edge; She takes cheekily from her hot head the measure of things that only judge themselves.
Wallensteins Tod II, 2. (Wallenstein)
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All parts have - to various extents. In order to mitigate the chronic ferromagnetic syndrome with a wide range of symptoms, such as sharp transients, sorely disordered dipole orientations, hysteresis and saturation, use large amorphous or mu-metal core transformers and block DC from entering the windings.
What with all the parasitics and other physics standing in the way of having an enjoyable listening session at home . . .
Throw away all your Hi Fi Stereos; and only listen to live concerts (with earplugs if it is too loud).
Sorry, but I choose to enjoy listening to what I have right here at home.
(the concerts hear are all shut down).
Throw away all your Hi Fi Stereos; and only listen to live concerts (with earplugs if it is too loud).
Sorry, but I choose to enjoy listening to what I have right here at home.
(the concerts hear are all shut down).
DC current is not a problem at all if not for size which is irrelevant to this this discussion as it has no significant drawbacks on performance. The SE transformer using normal Fe-Si cores IS as linear as exotic materials precisely because it has an AIR gap the MOST linear material! On top of that there is no zero-crossing...that's a sharp (un-necessary and unwanted) transient happening TWICE in parafeed both in the transformer and coupling capacitor and NEVER happening in gapped transformers.
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45,
Agreed.
Thanks!
There is more than one valid topology.
That is why I built a phase inverter to drive a dual channel single ended amp (per mono-block).
I reversed the output transformer B+ and Plate connections on one single ended amp, and then paralleled the Common, 4, 8, and 16 Taps of the 2 output transformers.
That creates a Pseudo Push Pull output that has 2 air gaps, and No zero crossings.
I designed and built it, but then I heard that the French had done that topology years before me.
Agreed.
Thanks!
There is more than one valid topology.
That is why I built a phase inverter to drive a dual channel single ended amp (per mono-block).
I reversed the output transformer B+ and Plate connections on one single ended amp, and then paralleled the Common, 4, 8, and 16 Taps of the 2 output transformers.
That creates a Pseudo Push Pull output that has 2 air gaps, and No zero crossings.
I designed and built it, but then I heard that the French had done that topology years before me.
IPSE DIXIT. I have never seen an optimized room at dealers places....even, or better especially, those who sell outrageously expensive stuff.
Really. Have you written something objective until now? I can't see it.
Hi-end is for believers....
Exactly. Stuff for believers with big wallets...
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