@ Royville
In this thread we discuss mostly the P3A as a circuit give or take as was. I would like to stay focused on that ...secondly recommendation about parallel input capacitors is based on what ??? listening tests ??/ then your listening test is under question ....
""treble is a little recessed."" next to what ?? again this is a listening result with your source and your speakers ??? then again your listening test is under question ...
What i am trying to point out here is that measuring results and circuit analysis could add something to the thread but listening tests will only confuse people since if you are working with Z speakers and X sources there is going to be way to many variables ...
Kind regards
Sakis
In this thread we discuss mostly the P3A as a circuit give or take as was. I would like to stay focused on that ...secondly recommendation about parallel input capacitors is based on what ??? listening tests ??/ then your listening test is under question ....
""treble is a little recessed."" next to what ?? again this is a listening result with your source and your speakers ??? then again your listening test is under question ...
What i am trying to point out here is that measuring results and circuit analysis could add something to the thread but listening tests will only confuse people since if you are working with Z speakers and X sources there is going to be way to many variables ...
Kind regards
Sakis
Mr Sakis,
I wasn't offering any recommendations about anything ! - only questions, and I don't have any test equipment as such to test with - only my ears!
Any way, point taken, apologies offered, and I will refrain from any future posts.
Kind regards
Roy.
I wasn't offering any recommendations about anything ! - only questions, and I don't have any test equipment as such to test with - only my ears!
Any way, point taken, apologies offered, and I will refrain from any future posts.
Kind regards
Roy.
royville,
ultrasonic input filter in P3A is mild and can not cause any subjective deficit of HF in audio band. I can not hear HF deficit in it, and not even in amps that have 1k/1000pF combination (like for instance Alesis RA150), let alone 1k/100pF! The cause of your problem lies somewhere else.
ultrasonic input filter in P3A is mild and can not cause any subjective deficit of HF in audio band. I can not hear HF deficit in it, and not even in amps that have 1k/1000pF combination (like for instance Alesis RA150), let alone 1k/100pF! The cause of your problem lies somewhere else.
Here is another CFP with another approach to join the list
The NAD C315BEE that uses a CFP output stage uses common heatsink( separated ) for the drivers and the Vbe multiplier While a second Vbe is attached on the main heatsink and both of them work parallel .
It seems to me that the issue has troubled many people and there should be some juice there after all .
yet again in the near feature i will approach a P3A input stage with an Alchemist forseti output stage .
Kind regards
Sakis
The NAD C315BEE that uses a CFP output stage uses common heatsink( separated ) for the drivers and the Vbe multiplier While a second Vbe is attached on the main heatsink and both of them work parallel .
It seems to me that the issue has troubled many people and there should be some juice there after all .
yet again in the near feature i will approach a P3A input stage with an Alchemist forseti output stage .
Kind regards
Sakis
HEGEN H1 knocked me off my chair .... i was jaw dropped by its sound didnt made comparison tests but yes from the first click this machine can play very well .
Hi Sakis, have you got a schematic for H1? Would be interesting to see. It looks cool inside, lots of SMD parts. Although, transformer in the corner makes it a bit "phisically" unbalanced 🙂
Valery no ...not yet i will get it within a few days
The circuit and the design is extremely simple and very conventional alike many we have seen in the past
There is something made different in the feedback ...It is described with "words" in the company brochure and inside the amp exists a piggy board with packed pcb that includes that . It is named sound engine i think and i expect that even if i manage to get a schematic still this pcb will be a black box
It says something like no feedback and if some needed this is broken in smaller areas /stage of the amp and works only if needed
I will have to study this a bit more
The circuit and the design is extremely simple and very conventional alike many we have seen in the past
There is something made different in the feedback ...It is described with "words" in the company brochure and inside the amp exists a piggy board with packed pcb that includes that . It is named sound engine i think and i expect that even if i manage to get a schematic still this pcb will be a black box
It says something like no feedback and if some needed this is broken in smaller areas /stage of the amp and works only if needed
I will have to study this a bit more
HI there Sakis. Any new tales of repair and comparison adventures? I always enjoyed your posts about your amp servicing ....I miss them. 🙂
Well thank you for your kind words I enjoy my self the hifi porno mistakes and fun that i find inside audio amplifiers ...
Point is that so far the P3A remains my favorite amplifier of all times on its class and i haven find any other to replace it with better results , even though the growth of my repair business is that big that i may tell you that 1000 audio devices per year pass now days from my shop while the 65% of them is amplifiers .
So comparison in a local level has been extended to extreme levels and while the results are of no importance or similar to the ones posted before i don't see the point ...
Too much work and happy listening resulted to no more comparisons ....From now on i will only put under test only amplifiers that have a potential against the P3A combo ( like the Hegel )
There is plenty of fun reading in out web page East Electronics But i cannot promise how well the Google translate will work there .
Will see .. still i am open to any discussion related to the P3A .
I may also post some upgrades in the feature but i cannot promise when this is going to happen ...
Kind regards
Sakis
Point is that so far the P3A remains my favorite amplifier of all times on its class and i haven find any other to replace it with better results , even though the growth of my repair business is that big that i may tell you that 1000 audio devices per year pass now days from my shop while the 65% of them is amplifiers .
So comparison in a local level has been extended to extreme levels and while the results are of no importance or similar to the ones posted before i don't see the point ...
Too much work and happy listening resulted to no more comparisons ....From now on i will only put under test only amplifiers that have a potential against the P3A combo ( like the Hegel )
There is plenty of fun reading in out web page East Electronics But i cannot promise how well the Google translate will work there .
Will see .. still i am open to any discussion related to the P3A .
I may also post some upgrades in the feature but i cannot promise when this is going to happen ...
Kind regards
Sakis
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'hifi porno'...........made me laugh 🙂
No problems Sakis....understood.
One day I really must treat myself to a P3A and comb your posts for clues about any mods that may have slipped in.
Your site is much slicker than when I last looked at it some years ago. Looks great. I tried to do a bit of a google translate, but google keeps reporting back that it is 'already in English'! But it's not a problem.
Glad to hear that your business is humming along and that there is a good news story from your beautiful country. I spent a month or more there as a young backpacker way way back in '82 and I have very fond memories of the kindness and extreme generosity of all your countrymen I met. It made me humble.
Warm regards,
Kim
No problems Sakis....understood.
One day I really must treat myself to a P3A and comb your posts for clues about any mods that may have slipped in.
Your site is much slicker than when I last looked at it some years ago. Looks great. I tried to do a bit of a google translate, but google keeps reporting back that it is 'already in English'! But it's not a problem.
Glad to hear that your business is humming along and that there is a good news story from your beautiful country. I spent a month or more there as a young backpacker way way back in '82 and I have very fond memories of the kindness and extreme generosity of all your countrymen I met. It made me humble.
Warm regards,
Kim
You should try to translate articles from the site as text not the all site
Yes site is much better and working well .Proud to say that as we speak we have 20GB "download" per month .
Nice to hear that you visited once ...i wish i could say the same
Yes Greeks have a thing with kindness and generosity though many things have changed since 82 Some for the best and others for the worst .
I think Greeks have too much contact with technology that now days obviously need ...minor adjustments !!!
Kind regards
Sakis
Yes site is much better and working well .Proud to say that as we speak we have 20GB "download" per month .
Nice to hear that you visited once ...i wish i could say the same
Yes Greeks have a thing with kindness and generosity though many things have changed since 82 Some for the best and others for the worst .
I think Greeks have too much contact with technology that now days obviously need ...minor adjustments !!!
Kind regards
Sakis
We are having capital controls so my time is limited Just a quick question
I am 100% against capacitor less input on the P3A In general i am against it in any amplifier
Though i am working on an application that the P3A will be implemented as an integrated amplifier with a pre that includes capacitor in the output so safe there to proceed
The question though is that also in this specific application a 47K logger is going to be located between pre and amp
is there a DC issue involved in the wiper ? Do i expect something to go wrong there ?
Thank you
Kind regards
Sakis
I am 100% against capacitor less input on the P3A In general i am against it in any amplifier
Though i am working on an application that the P3A will be implemented as an integrated amplifier with a pre that includes capacitor in the output so safe there to proceed
The question though is that also in this specific application a 47K logger is going to be located between pre and amp
is there a DC issue involved in the wiper ? Do i expect something to go wrong there ?
Thank you
Kind regards
Sakis
Hi Sakis,
As long as the P3a doesn't present a DC offset between the wiper of the potentiometer and ground, I do not envisage a problem. Otherwise, you might end up with a noisy control over time.
That's good sequence of building blocks that guarantee there won't be DC problem at the wiper: Pre with output cap, pot (which replaces resistor to ground), P3A (without input high pass filter.
Removing the resistor to ground at the P3A input is not advisable. This would mean relying on the volume control's wiper connection for the signal ground which is used as a DC reference for the +ve input to the amplifier LTP (base of Q1 on the ESP web page). Potentiometers do age and become dirty over time, which could potentially have a catastrophic effect on the DC stability.
Leaving R2 intact also offers the possibility of using a 100K linear potentiometer to give a logarithmic control curve. See here: Potentiometers (Beginners' Guide to Pots)
yeap!! now i am confused also with that ...Obviously there is no intention on removing the resistor to ground from the LTP since this will bring it out of balance
Exactly. I didn't imagine that was ever your intention, but felt it worth mentioning to ivanlukic. Regarding your proposed integrated set up, you would need to ensure that there is no risk of anyone bypassing the pre-amplifier and connecting (unknown) sources directly to the P3A input stage. I don't believe DC offsets will be an issue in your proposal as the inverting input to the LTP is already AC coupled to ground via C3.