sap15n sap15p thermaltrack pair was used heavily in both touring(acive speaker behringer) and audiophile (arcam diva p85-who's thermal management isn't trivial) equipment but for some unknown reason i never saw them stocked with the usual retaillers.There are lots of good sanken parts used by big manufacturers that rarely get on the market... datasheet SAP15P
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I read somewhere that to have the emitter resistor embedded is not a good design choice ? it gets hot and can cause issues ?
Musical Fidelity has used them in some amps. Do they really allow for simpler schematics ? 🙄
But i have to reiterate that to get better sound (and maybe even better measurements) taking out components for me is really mindbowling 😱
Anyway .... i will try, if i find it, to change some values in my bride of zen line preamp attempt in order to be able to use it with a 48VDC smps from Meanwell. I have already suggested that most of its noise is out of the audio range and i am curious to listen.
From what i have gathered the BOZ project is very useful to check the quality of a PSU having very low PSRR .... therefore all the noise reaching the mosfet will be presented at the output
Next one i would like to try a Sziklai pair. I understand it was very popular in the '70s and early '80s ?
I guess it is very difficult to think to more minimalist active line stages ... speaking of solid state.
Musical Fidelity has used them in some amps. Do they really allow for simpler schematics ? 🙄
But i have to reiterate that to get better sound (and maybe even better measurements) taking out components for me is really mindbowling 😱
Anyway .... i will try, if i find it, to change some values in my bride of zen line preamp attempt in order to be able to use it with a 48VDC smps from Meanwell. I have already suggested that most of its noise is out of the audio range and i am curious to listen.
From what i have gathered the BOZ project is very useful to check the quality of a PSU having very low PSRR .... therefore all the noise reaching the mosfet will be presented at the output
Next one i would like to try a Sziklai pair. I understand it was very popular in the '70s and early '80s ?
I guess it is very difficult to think to more minimalist active line stages ... speaking of solid state.
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This is nonsense, do you think engineers design a circuit then play a game of jenga to make improvements, that's not how engineers design anything.
Hi ! so you say that given a commercial unit it is not possible to improve its performance both at the lab bench and at the listening test ?
As i said above there was a talent guy who was improving the sound of Denon dvd players by-passing some parts and replacing others.
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there was an old amplifier design where they reduced VAS feedback cap until it just didnt oscillate.
after it was put into production some oscillated due to spread in components.
they had to increase the cap a bit more to cover all possibilities.
this is the difference between design theory and practice.
after it was put into production some oscillated due to spread in components.
they had to increase the cap a bit more to cover all possibilities.
this is the difference between design theory and practice.
back in the day I had a kenwood model 600 from the late 70s or early 80s, it was the best sounding amp I've ever had.....does anyone have a schematic or a understanding of what they might have done to do it?
I do remember kenwood advertising of simple circuits for the best sound.
I do remember kenwood advertising of simple circuits for the best sound.
10...15 years ago I had a CRT LG Tv set who's chassis was version A.There were other two versions for the same chassis, , heavily stripped out of components.My LG never got any problem although we had some heavy ligtning activity in the summertime and the mains all over up to 380v ac .I used to fix countless from the other versions with blown components.
It seems to me that two 'laws' operate in design.
Rather like the curves in Raoult's Law, one going up and the other down on the graph, there is a desire to improve, which results in designers increasing complexity to improve performance, and another desire to reduce complexity because we know that more components suggests more to contribute error, and also proneness to failure.
Rather like the curves in Raoult's Law, one going up and the other down on the graph, there is a desire to improve, which results in designers increasing complexity to improve performance, and another desire to reduce complexity because we know that more components suggests more to contribute error, and also proneness to failure.
I never knew there was actually a name for such behavior. Muntzing strikes me as an misapplication/misconstruing of Einstein's famous dictum; "Everything should be made as simple as possible, but no simpler.”
Earl Muntz was a legend in his own time.
The guy's design principal cracks me up even today.
He's go around the lab, leaning over his techs, and started clipping out parts until the set barely worked.
The guy's design principal cracks me up even today.
He's go around the lab, leaning over his techs, and started clipping out parts until the set barely worked.
He worked with valves which are more resilient to supply transients output and input overload.You can't do the same with silicon...Reliability is more important than performance.On the other hand using an op-amp instead of a bunch of discretes is often more reliable and technically better too as many Muntzing like guys made that op-amp ...
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Hi ! thank you so much indeed 🙂 these are nice clean and simple i think
The fact that they sound good it is also very interesting.
This could be a very good option for a low power integrated i guess 🙄
I have also another curiosity ... there is another schematic that i love ... the diamond buffer (maybe because it is symmetrical ?)
The question is ... what is a typical PSRR for this topology ? i mean, can it be powered with an unregulated power supply or it really need a regulated one ? i think i have to ask in a specific thread about diamond buffer ... i am doing this
Thanks a lot again.
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"I have also another curiosity ... there is another schematic that i love ... the diamond buffer (maybe because it is symmetrical ?)
The question is ... what is a typical PSRR for this topology ? i mean, can it be powered with an unregulated power supply or it really need a regulated one ? i think i have to ask in a specific thread about diamond buffer ... i am doing this"
Do you use Google or are you expecting people to copy-paste the whole internat database for you??
Why might a diamond buffer sound better? - diyAudio
Andrea Ciuffoli - Home Page 5 - DOCUMENTATION
D400_Manual_Schem.pdf - Audio Research
PIONEER A-09 SM Service Manual download, schematics, eeprom, repair info for electronics experts
The question is ... what is a typical PSRR for this topology ? i mean, can it be powered with an unregulated power supply or it really need a regulated one ? i think i have to ask in a specific thread about diamond buffer ... i am doing this"
Do you use Google or are you expecting people to copy-paste the whole internat database for you??
Why might a diamond buffer sound better? - diyAudio
Andrea Ciuffoli - Home Page 5 - DOCUMENTATION
D400_Manual_Schem.pdf - Audio Research
PIONEER A-09 SM Service Manual download, schematics, eeprom, repair info for electronics experts
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Thank you !!! 🙂 sincerely i have searched around but i did not find this very interesting posts ... and blogs. This is exactly the kind of info i am looking for.
Extremely interesting here ...
Even if when he says
may i answer would be clearly no ... what kind of difference can provide 6dB less noise ? no one.
So i really think that the output stage must be inside the feedback loop and correct by it.
I start to think that FB is a godgift ... the only question remaining is there an optimum amount of FB for not only great sound but also great measurements ?
I guess that zero feedback and low distortion are impossible to get at the same time. FB is really needed.
Moreover i am pretty sure that my future line stage will be just a buffer.
Lately i have always had to fight with too high gain ...
i do not need gain at all before amps. I have already seen one very interesting in the Pioneer A09 schematic ... if it is good for maybe the best Pioneer integrated ever it could be good also for me.
I will have to learn to use google really ... it is impressive the amount of info available really.
Thank you sincerely again. 🙂
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you missed the Pioneer's output diamond buffer which has no global feedback but has a different approach for that matter to keep distortions low enough, not very low though...
Audio research has another diamond output too
For the input buffer you might like to read this Tektronix manual who's bufferes were used by harman kardon in some designs i think .
https://www.davmar.org/TE/TekConcepts/TekVertAmpCircuits.pdf
Audio research has another diamond output too
For the input buffer you might like to read this Tektronix manual who's bufferes were used by harman kardon in some designs i think .
https://www.davmar.org/TE/TekConcepts/TekVertAmpCircuits.pdf
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I didn't say it was impossible, but putting things into perspective consumer products are typically made to a price point and last a period of time that is acceptable to the consumer by in which time the product is obsolete or is uneconomical to repair, so the consumer simply buys a new one and we repeat the cycle.
In this case it maybe possible to make improvements, but you need to determine what are you trying to achieve by doing so, because it maybe the case that the improvements are so minor that its uneconomical.
Do you mean this thread - my dvd denon 2900 mod dazzz style 🙂
I wouldn't say talented although he may appear to be to those who lack sufficient electronics education. There are so many things wrong with the modifications that it is a tall ask to say they were improvements. Any improvements were simply a statement of replacing components therefore it must be better. I trust the guys at Denon.
There's no correlation between complexity and failure. Industrial, automotive and aerospace electronics are examples.
This is so obviously wrong, I don' t understand one can think of such a thing.
Have a look at how a MTBF is calculated ?