Bernhard said:
I actually bulid cmoy headphones amplifier,connected to my modded Rotel 991 with just PCM63p-k ,and was able to hear so much details,and I can say PCM63p-k really don't need to be piggy backed, or modded other way. It is extremely hi-res chip and all my other equipment (Rotel 1055 ,JM Lab 816S) have not enough resolution to play all details.
AnthonyAsh said:
How true, usuallly speakers are the weakest part of the chain and it is questionable to look for the last 0.05% of improvement of the DAC if speakers need to improved another 50%.
But I have tested PCM 63 J and K2 and found harmonics, I don`t think it is first choice.
Also there are so many traps in judging sound...
I always used to compare DACs with headphones plugged directly to the CDP.
Now I found it sounds wrong, maybe because the headphone amps are all bad or because my headphones present a strange load to the poor op amps, those are electret condenser type, very rare, never have seen them on ebay...
But I have tested PCM 63 J and K2 and found harmonics, I don`t think it is first choice.
Hello ,tell me please which DAC doesn't have garmonics?
.May be quantum amplifier from future.
I heard from dac dyi amateurs,the best DACs for CD is pcm63p-k, ad1862 ,ad1865-k .Do you have other suggestions?
SincerelyA
Hello ,tell me please which DAC doesn't have garmonics?
.May be quantum amplifier from future.I heard from dac dyi amateurs,the best DACs for CD is pcm63p-k, ad1862 ,ad1865-k .Do you have other suggestions?
SincerelyA
I Have been following this discussion for some time now and really thought this is chasing a very small mod with very little gain......well I thought I might give it a try since I had a spare set of PCM63 laying around . At first I had problems doing the correct connections, since one has to search through all the info on the site.
Conclusion. SIMPLY AWESOME (and I wasn't even using K's. simple garden variety P's). focusing is much better, sound staging is bigger and more accurate. ever heard of bass focusing? Dr H (Ryan) heard it and was surprised. Tonality is neutral without any artifacts. Just neutral
So how is it done?
First try and use a 28-pin socket and mount that on top of the original chip (then remove the following pins 1, 3, 4, 9, 10, 23, 24, 25 this way you do not mess up your beautiful PCM63) the next part is very important. Mount a 10uf 25Vcap between pin 1 and pin 28 negative will point to pin 28. Then mount two more caps of the same value on pin 3 and 4 with negative to ground (pin 7) all these caps will fit into the socket area so you will not have caps sticking out all over the show referencing ground
Try this mod. It is truly worth-it
Conclusion. SIMPLY AWESOME (and I wasn't even using K's. simple garden variety P's). focusing is much better, sound staging is bigger and more accurate. ever heard of bass focusing? Dr H (Ryan) heard it and was surprised. Tonality is neutral without any artifacts. Just neutral
So how is it done?
First try and use a 28-pin socket and mount that on top of the original chip (then remove the following pins 1, 3, 4, 9, 10, 23, 24, 25 this way you do not mess up your beautiful PCM63) the next part is very important. Mount a 10uf 25Vcap between pin 1 and pin 28 negative will point to pin 28. Then mount two more caps of the same value on pin 3 and 4 with negative to ground (pin 7) all these caps will fit into the socket area so you will not have caps sticking out all over the show referencing ground
Try this mod. It is truly worth-it
Sorry ...
You are piggy-packing a 28pin IC-Socket with removed pins 1, 3, 4, 9, 10, 23, 24, 25 to the PCM63. After that you are connect a capacitor to (separated) pin 1 in this socket ? That's nonsense.
It's even nonsense to disconnect these pins of the PCM from the Board, especially pins 9 & 10 (if they in use).
I understand, that you are paralleling up decoupling capacitors, but for that you don't need to disconnect pins. That you can do easily on the bottom of the Board.
Regards
Jobstens
You are piggy-packing a 28pin IC-Socket with removed pins 1, 3, 4, 9, 10, 23, 24, 25 to the PCM63. After that you are connect a capacitor to (separated) pin 1 in this socket ? That's nonsense.
It's even nonsense to disconnect these pins of the PCM from the Board, especially pins 9 & 10 (if they in use).
I understand, that you are paralleling up decoupling capacitors, but for that you don't need to disconnect pins. That you can do easily on the bottom of the Board.
Regards
Jobstens
What don't you understand
Jobstens I think you have a completely the wrong idea of what I have done, maybe you should read my message again
First. You keep the original PCM 63 in place. Then you mount a 28 pin socket on top of it with the mentioned pins removed. (Read the other threads and you might see that they are NOT required.) For neatness. You can mount the decoupling caps inside the socket area. (If you feel that you want caps sticking out all over the show. is my guest. I like the neatness of my arrangement). Once you have connected pin 1 with pin 28 via a cap and 3 and for to ground. Stick the second chip into the sockets. (we are not piggy backing a 28 pin chip on the chip)
we are using it as a method to make the installation neat and tidy so you can re-use the chip if you feel like this mod does not work for you
Try it for yourself if you are so sceptical
Rudi
Jobstens I think you have a completely the wrong idea of what I have done, maybe you should read my message again
First. You keep the original PCM 63 in place. Then you mount a 28 pin socket on top of it with the mentioned pins removed. (Read the other threads and you might see that they are NOT required.) For neatness. You can mount the decoupling caps inside the socket area. (If you feel that you want caps sticking out all over the show. is my guest. I like the neatness of my arrangement). Once you have connected pin 1 with pin 28 via a cap and 3 and for to ground. Stick the second chip into the sockets. (we are not piggy backing a 28 pin chip on the chip)
we are using it as a method to make the installation neat and tidy so you can re-use the chip if you feel like this mod does not work for you Try it for yourself if you are so sceptical
Rudi
TJ said:
Hi TJ
I use the DF1700 in my DAC and it drives the 4 chips just fine. but regarding the push pull. i doubt that you are going to be able to do that mod easily. you would need a complete re-design as far as i know. do the mod i described and you will be rewarded in a big way. but that also depend on the rest of your system.
regards
Rudi
Just wanna throw in another measurement.
Compared low level performance of PCM53 one for both channels with PCM63J made in USA.
Upper is PCM53 K7 = noise = -62,9dB
Lower is PCM63J K7 = -47,5 dB
Those PCM63 USA are from Pioneer PD8500 and the worst PCM63 I have seen yet. PCM63 Japan from another PD8500 was much better but still mediocre. Same with K and K2 I got from Forum members.
Still it is possible that performance is degraded by OS chip, this is SM5813 in PD8500.
I know that TDA1541A performs very different depending on A/B version of SAA7220.
Compared low level performance of PCM53 one for both channels with PCM63J made in USA.
Upper is PCM53 K7 = noise = -62,9dB
Lower is PCM63J K7 = -47,5 dB
Those PCM63 USA are from Pioneer PD8500 and the worst PCM63 I have seen yet. PCM63 Japan from another PD8500 was much better but still mediocre. Same with K and K2 I got from Forum members.
Still it is possible that performance is degraded by OS chip, this is SM5813 in PD8500.
I know that TDA1541A performs very different depending on A/B version of SAA7220.
TJ said:
TJ , unfortuneately i do not have a answer for you. but i doubt that more than 2 is going to make that much difference. but having said that. i will try a third just to put my mind at ease.
but one mod that would pay off for you is to get rid of the stock valves ( they are really crap) and replace it with Siemens CCA (gold pin - if you can find them) this will give you a much better improvement than a stack of chips (non digital stuff but for the benefit of TJ)
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