I do not think that any bigger company nowadays is interested to buy any linear audio power amp design. You are some decades too late with your invention.
How could that be possible? Please tell me why by pointing out what is catastrophic in schematics. There will be some compromise in a commercial product but I wouldn't call that catastrophic. What is not catastrophic by your standard I wonder. If you mean some few watt output diy ones that cannot drive a modern speaker, I think that's more catastrophic. Why not use tubes in the first place.
I totally believe what you are saying. I want to build a bigger speaker long ago, but just cannot find a tweeter have both astonishing transparency and low enough frequency to work with big woofer in 2 way setup. But I find a cheap planar pulled out from GM vehicles makes it possible now.
You can try to hear some youtube recordings with planar headphones easily tells the difference. Many of them are recorded with dedicate mics. But it is just hard to get a confirmed result. Becaus they usually play different songs for different amp. But I still can tell the difference, not to mention many mediocre amps they are really grainy and dull when you just listen to them for several seconds no matter what song is playing. But be sure to compare videos from same youtubers.
And by no means I what them to let go, I haven't found any non vfet amp I love more
Man whats u are saying is mind blowing to me, I can understand most of them but I didn't catch up the topology thing drain to drain thing. I will learn something to understand what you are telling me, thanks for the information. Have you heard ta-8650 or 8550?
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Come on don't be so mean. Besides that is not true. the lowest distortion amp that beat AudioScienceReview's reference amp is topping la90 from china which is a class ab linear amp.
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Are your amplifiers restored...(I do not mean recapped)?
Also, be aware that you might hear reviews in the internet from "influencers" that know nothing or very little about these amps. My suggestion is to try for yourself, keep the amps you like and let go of those you don't.
Also, going back to my first question: you are refencing here amplifiers that are pushing 50 years of service. While that is a high benchmark for any amp in terms of longevity, it is also a give you a reason to scrutinize any review from "influencers" and ask if the units they review were properly restored. Otherwise, what you are comparing is the aging of one amp compared to the other.
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Have you tried this tweeter? Its designed for 2way.
https://essspeakers.store/products/the-original-great-ess-heil-amt-air-motion-transformer™
I haven't but I have a small AMT tweeter I don't love, This one looks good tough, but I want to try out that Harman-kardon $15 planar full-range at first. They shouldn't be bad at all considering they even work well as headphones, did u open the thread for that speaker there are teardown photos inside. Thanks your suggestion, just put that ESS later sometimes.
Rumors say sonys is more musical than yamahas but you don't love the old commercial ones anyway. But I think none is true: The vfet is not at it best in complex circuits nor Vfet is at best in simple circuits. Most of the sound characteristic comes from circuits working preciple itself those BJT mosfet DIY ones is sweet sound too, so a sweet vfet amp is sweet not only thanks to that vfet. But they lack power, hard to judge which is at best use of vfet. This sansui ba-1000 looks simpler but I haven't find a schematic to learn. I haven't tried any DIY V-fet amp yet. I heard form some friends bought some low power diy vet amp and let go for cheaper because it couldn't drive his speaker.
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Yeah I looked into Ta-8650 schematic, the source are connected why is that makes a different, I am not that deep into electronics could u explain? Sound like I should looking for Ta-5650 instead of ta-8650?
No they all haven't been restored, I am not capable to restore them for now. just checked the idle current. I fact which I am worried the most is the Yamaha b-1. Working great so far, even 50 years passed they still sound the best, I should look into restoration, that should bring more transparency I love. Maybe I should get a cheap and not rare one to start with. I have some experience fabricating tube amps with success but I don't dare to touch these precious vfets for now. And I trust an average repair guy no more than myself.
and did you hear it as it was in original condition 30-40 years old?
what about the complexity? can we get a one stage amp to put out 200W and sound any decent?
Simplified circuits, single stage or two stage amps no-NFB are excellent at low output listening levels. But they also typically require a serious preamp in most cases, so is a sense some of the work a high gain multi-stage amp does, is offloaded to the preamp instead in the case of simplified low gain amplifier. In reality we are talking about apples an oranges when comparing the simplified circuit v-fet amps we build here or even some of the commercial products such as the FW, with the larger v-fet siblings from the 70s. What I can assure you is that with proper TLC the 70s amps are a high standard to match, at low listening levels and all the way into 100W+
BTW, Most of the complexity of these older v-fet amps is concentrated in the protection circuit. That is why the are still clapping after close to 50 years 😉
Taking a look at the B-1 circuit as an example, where every power supply is regulated, I could see the good fit of Nelson's statement where he wittingly said (paraphrasing): "it looks like they got paid by part" 🙂...but again, there are a lot of B-1s around that are 50 years old and still work. Get one restored and in your system, and you are in for a pleasant surprised.
yes, you are rightfully worried about the B-1. Unfortunately, the B-1 is the most complex rebuild and most difficult to source main filter caps for. Yamaha chose a dual-cap for filter caps and those are difficult to replace. Sony did too, for the TA-8650 and for the big dog, TAN-8550, but Sony uses a single dual-cap for main filter / PSU and the B-1 has two of them..so also a more expensive replacement.
Your B-2 also has a difficult issue to address (and still keep all functionalities of the unit), which is the front selector assembly.
The Sansui has a fairly simplified circuit and parts that are easy to replace. With the Sansui, a good old recap will get you 90% to where the amp will sound as good as new. That is a sweet sounding amp.
As far as the Sony v-fet amps sounding better, that is something you must decide for yourself and not get influenced by the internet.
BTW, I do have the amps you have and very much every v-fet amp made in the 70s, and many miles under the tires listening to them....in different restored conditions.
"I try to sell it then, AD, TI, name it." These are the global players, not some small company like topping. Telling the truth is mean?!😕
I am not believed a "simple" diy amp could be an all-rounder. Sure they are good in a few applications but not all. I found out none of my or others low power simple diy project competes to top-tier vintage vfet amp. It all comes down what is personal liking, low power with full-range, lacks impact, and transparency, or modern philosophy lacks some "hi-fi" salt. What I love about vintage vfet amps is that they are the best compromise.
After all, sound is a perception in the brain, and we don't need to argue or choose one to live with, we can have them all, luckily.
After all, sound is a perception in the brain, and we don't need to argue or choose one to live with, we can have them all, luckily.
Oh seems these small companys occupied the most market, espacially for younger age.
Why do you think he is mean? I'd say he only speaks the truth. If the big semi companies were interested in linear audio devices, they would make much more of those devices. However, this is not where the money is for them.
You are mixing up things here. A low distortion amp can be made with pretty much any type of transistor or tube. That's not what VFETs are about.
Have you looked at the distortion of the recent VFET amps (Pass designs and follow ups)? They are terrible by the ASR standards. Still, many people like them for their good sound.
Perceived sound quality and distortion measurements are not well correlated (if THD is below 1% or so).
with multiple components to replace one transistors you certainly thought of the likely added parasitic elements??
Also, I am thinking that the low thermal runaway characteristics of the v-fet were also considered??
I look forward to hear more about your device.
BTW, I am sensing that you might have already looked into Sonys hybrid output stage used for TA-N7 and TA-F7. Any influence from that with your design?
YMMV when it comes to how they interact with different speakers. 0.001% THD could sound worse than 0.1% (or dare I suggest 1%) if the interaction with the speaker is poor. If for instance the tweeter has low sensitivity and can't be padded down with series resistance, the low distortion amp may sound worse due its relatively low output resistance at high frequencies.
Or, for instance, class B may look great on paper, but your 100dB efficient wave-guided tweeters bring out all the low-level grit that would otherwise be inaudible. Just an example.
Or, for instance, class B may look great on paper, but your 100dB efficient wave-guided tweeters bring out all the low-level grit that would otherwise be inaudible. Just an example.