I just have been looking at the picture, for me looks like fake : the marking is too far from the recess at pin1 !
You sure will have better result with the one you testimonied above and also the Ti talked in the thread that are crazy good for few bucks. And you will have the best sound by also not playing with opa but also playing on powersupplies and decoupling caps and the main smmothing caps of the power supply. Imho, YMMV...
You sure will have better result with the one you testimonied above and also the Ti talked in the thread that are crazy good for few bucks. And you will have the best sound by also not playing with opa but also playing on powersupplies and decoupling caps and the main smmothing caps of the power supply. Imho, YMMV...
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Has anyone already played with class A biasing in the context of an op amp ruling both the I/V and the buffer in one package as per Miro1360 design ?
Will it lowisch enough the distorsion to be heard or does it not matter cause modern good opa talked in this thread are good enough with very low noise and power supply rejection ?
Especially : is it possible to biass in class A (any interrest?) the opa861 when used as a buffer please ? I'm thinking about what Vunce made with the small form factor discrete opa copied from Pedja Rogic... it could permitt some class A operation on the buffer stage only ?!
Many thanks if any experience there...
Edit : link for illustration Biasing Op-Amps into Class A ; Re: Op Amps running Class A? - Jon Risch - Tweakers' Asylum ;
Will it lowisch enough the distorsion to be heard or does it not matter cause modern good opa talked in this thread are good enough with very low noise and power supply rejection ?
Especially : is it possible to biass in class A (any interrest?) the opa861 when used as a buffer please ? I'm thinking about what Vunce made with the small form factor discrete opa copied from Pedja Rogic... it could permitt some class A operation on the buffer stage only ?!
Many thanks if any experience there...
Edit : link for illustration Biasing Op-Amps into Class A ; Re: Op Amps running Class A? - Jon Risch - Tweakers' Asylum ;
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LME49990 genuine vs. fake
here is mine genuine and mine fake from ebay ... the genuine has a round hemispherical hole (all genuine LME49990 are only with this type of hole) ...
fake is with a flat hole or without a hole ...
there are many versions of china chips
the picture from @wealas, is the hole flat or is it hemispherical? not visible in the picture
another good example:
Fake LME49990 on the market
next example, where both are fake, even the left one is fake:
Fake LME49990 on the market
next example (left original, right is fake)
https://pbs.twimg.com/media/Dz62CMoUcAEIMtQ?format=jpg&name=small
another original:
https://ponpon.txt-nifty.com/.shared/image.html?/photos/uncategorized/2015/05/31/l49990back.png
here is mine genuine and mine fake from ebay ... the genuine has a round hemispherical hole (all genuine LME49990 are only with this type of hole) ...
fake is with a flat hole or without a hole ...
there are many versions of china chips
the picture from @wealas, is the hole flat or is it hemispherical? not visible in the picture
another good example:
Fake LME49990 on the market
next example, where both are fake, even the left one is fake:
Fake LME49990 on the market
next example (left original, right is fake)
https://pbs.twimg.com/media/Dz62CMoUcAEIMtQ?format=jpg&name=small
another original:
https://ponpon.txt-nifty.com/.shared/image.html?/photos/uncategorized/2015/05/31/l49990back.png
Attachments
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Almost forget to ask R10, R11 part of RC filter in BOM it is stated it can be omitted. When I checked on others pictures on all I can see the R10 and R11 is populated with resistor of course it wouldn't work otherwise. But if RC filter is omitted should one use jumper instead of resistor?
thx
thx
diyiggy,
would you please share more details about comparision between Nichicon ES, KZ, KW and Panasonic FR and FC
which specific application are you talking about
All the decouplings.
All are good on that list. The kz are a little difficult towork with and often I remove it after tryings.
The Nichicons but the ES are often given mellow but too much closed sound...lack of overture sometimes but can be a quality of very light clear oaps like the LME for instance...to be benchmark with the Pan FR.
The FC is very good...little hard to use...too much of them is bad, put it where it is working like more rarely the FM then you can get very good result on goids circuitries and layouts. ES is on the same league but I prefer the FC.
Your list is an excelent base to work with but the Kz imho I would replace for an UKA, but the KW are ggod enough imho.An Elna, the violetts or Tonorex are very usefull for main power supplies to test what work best for your whole hifi sound. For instance swap with FC...FR...KW...and Elna...for main smoothing purposes then you will have very different results...one could be better for you related to what you hear at the end.
Then one can adjust with different local decouplings to fine tune.
No universal answers but a long work to tailor your dac haute couture way vis a vis of the rest of your system. It pays off.
Forgott for smoothing...if no Elna on hands, i don t talk about the Silmic 2 that I don t like because capricious like a kz and long to burn in to get its ending result, get some Rubycon Longue life that can calm down a little some too much light but very good aops like 4562 or LME types....
Sirry to talk caps sound, it s a short cut to win time.
Ad 1862 deserves that work to get the best.
All are good on that list. The kz are a little difficult towork with and often I remove it after tryings.
The Nichicons but the ES are often given mellow but too much closed sound...lack of overture sometimes but can be a quality of very light clear oaps like the LME for instance...to be benchmark with the Pan FR.
The FC is very good...little hard to use...too much of them is bad, put it where it is working like more rarely the FM then you can get very good result on goids circuitries and layouts. ES is on the same league but I prefer the FC.
Your list is an excelent base to work with but the Kz imho I would replace for an UKA, but the KW are ggod enough imho.An Elna, the violetts or Tonorex are very usefull for main power supplies to test what work best for your whole hifi sound. For instance swap with FC...FR...KW...and Elna...for main smoothing purposes then you will have very different results...one could be better for you related to what you hear at the end.
Then one can adjust with different local decouplings to fine tune.
No universal answers but a long work to tailor your dac haute couture way vis a vis of the rest of your system. It pays off.
Forgott for smoothing...if no Elna on hands, i don t talk about the Silmic 2 that I don t like because capricious like a kz and long to burn in to get its ending result, get some Rubycon Longue life that can calm down a little some too much light but very good aops like 4562 or LME types....
Sirry to talk caps sound, it s a short cut to win time.
Ad 1862 deserves that work to get the best.
LME49990 is worth a try ... they are very close to each other ... LME49990 is clean, neutral ... AD4627 is clean too and a little deeper but not very much, it is a question of preference because both are good ... my choice over these two is LM6171 for a better dynamics - but again, not that much ... just a small details that everyone can perceive differently ... so try and choose is the way
do you consider Panasonic FR top of the game with FC close
what Is difference and advantage of FR compared to FC
of all mentioned which do you prefer In position of post 1084 / 1963 regulator cap
did you try Nichicon ES as post regulator cap
what Is difference and advantage of FR compared to FC
of all mentioned which do you prefer In position of post 1084 / 1963 regulator cap
did you try Nichicon ES as post regulator cap
This is two caps with I tweak a lot The ES being a non polar, I never use it in PS purposes... sometimes at the end of local decoupling if the system needs some light or opening. someties in // with another one, of course in serie for dc bloxking at the output of a circuitry for dc blocking purpose if needed for a try among many others.
There is no advantage of FR vs FC or the opposit : you need to try to know what is needed in relation to your own system cause what works for me may be not working for you : ater the source there are a lot of devices untill you hear what happen.
When I tweak with caps I'm working with hundred of caps that are sometimes same models but with voltage variations or uF or both inside a same model range for instance.
Often FR are more on mat sound side, FC as the ES on the light/lightning side, choose what you need in relation to your reference then tweak on a second board always cap by cap with a listening test.
Of course more important is the power supplies typology, regulator, power traffo... passive parts are a small part of the whole ... while important enough according to me to make a dac bad or good. Nothing wrong with all the brands we talked about in he thread since the beginning.
There is no advantage of FR vs FC or the opposit : you need to try to know what is needed in relation to your own system cause what works for me may be not working for you : ater the source there are a lot of devices untill you hear what happen.
When I tweak with caps I'm working with hundred of caps that are sometimes same models but with voltage variations or uF or both inside a same model range for instance.
Often FR are more on mat sound side, FC as the ES on the light/lightning side, choose what you need in relation to your reference then tweak on a second board always cap by cap with a listening test.
Of course more important is the power supplies typology, regulator, power traffo... passive parts are a small part of the whole ... while important enough according to me to make a dac bad or good. Nothing wrong with all the brands we talked about in he thread since the beginning.
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Wow Diyiggy!! You’ve got lots of tweaking time
You have the patience of a saint, I’m not so patient
Enjoy your weekend!