QA-550 SD card 16/44.1 WAV transport

intresting

i really enjoyed all the posts on this little player.ia m expecting one in a couple of days.i use a tda1541dac with a double crown chip.i also use a marantz94 modded as transport.cd94 is old but such a great transport so i am in search for a replacement before my cd94 dies.i will post my thoughts on this player.
has anybody used a 12v battery power supply with it?
 
i really enjoyed all the posts on this little player.ia m expecting one in a couple of days.i use a tda1541dac with a double crown chip.i also use a marantz94 modded as transport.cd94 is old but such a great transport so i am in search for a replacement before my cd94 dies.i will post my thoughts on this player.
has anybody used a 12v battery power supply with it?

Yes I've used a 12V battery - seems fine to me.
I2S direct from the player to your dac will very likely give the best result.
 
its good

well i got it and its playing.with the standard power supply.not as good as mycd94.however their is pottential here.out comes the soldering iron.i removed two sanyo oscons and put in dubelier oil filled caps 8uf.why?
i wanted more weight and body too much whiteness on my systems stock.
more changes latter.12v car battery big inprovement to sound.its also out of its case.i will do a follow up as i play around with it more.12s is next.
 

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Hi Friends,

Sorry for my bad English.
I've bought this nice player and I've noticed good improvement with Pb-gel battery too ( I'm using it with a PCM1794 dac, dual mono, battery powered).

I've compared it with my CDpro2 ( reclocked with Tent's X0) and the difference is in favor of CD pro.
I would say at the moment ;)
QA 550 in my opinion seems to me to have more stable image, but has less clarity, also bass seems to have less energy in respect to cdpro.

Searching for the reason, I've noticed in my old scope that the BCK / SLCK signals seem "dirty", expecially in the low level ( the I2s output of my cdpro2 is perfect)

Someone had the chance to evauluate the I2S coming from QA 550 with a good scope?.

To make a fair comparison I think I need to substitute X0 with a Tent's unit and reclock I2S


Bye



PS: I've had also a little problem interfacing my unit with my dac. I2S signal in my unit was weak (expecially LRCK ) , and to interface it correctly with 1794 I hat to buffer each I2S signal.
 
here is my mod to this SD card player. the mod includes audio-gd's ICAC SPDIF module and 2 shunt regulated power supply boards, supplying power rails +/-15V for the ICAC module and +5V for the player ( removed internal 7805 regulator) and independant +3.3V for the clock inside the QA550 player.

now it sounds 10 times better it was and also better than a lot of CDP’s i have heard.

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Hello again Gidu

Correction to the above: I think I may have had your problem once!
What program are you using to extract the audio to wav? I remember that when I used Max with the Mac I had a similar problem to yours, but I now use xACT and it's fine.

John
 
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Hello !
On my QA-550, i have a big noise, like a "clic", just before the beginning of each track !Gidu

WAV file without extention will have 44 bytes headder.
So easy programming method is just jump 44 bytes - then play the bytes.
If WAV file has extended header, there are some non zero data, after 44 bytes. QA-550 looks like just jump in to 45 byte, and here is not 0x0000.

look into your WAV file, by some Binary(HEX) editor.
 
Hello again Gidu

Correction to the above: I think I may have had your problem once!
What program are you using to extract the audio to wav? I remember that when I used Max with the Mac I had a similar problem to yours, but I now use xACT and it's fine.

John

Hello John !

I was using Max on my iMac ... I will try xACT !

Thank you for your answer !

PS : yesterday, i send an email to Clark Chen and he answered me that he will send to me a new firmware in a few days witch will probably correct my problem ... so, i have to wait for it !

Gidu
 
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WAV file without extention will have 44 bytes headder.
So easy programming method is just jump 44 bytes - then play the bytes.
If WAV file has extended header, there are some non zero data, after 44 bytes. QA-550 looks like just jump in to 45 byte, and here is not 0x0000.

look into your WAV file, by some Binary(HEX) editor.

Hello KOON3876 !

All my files have .wav extension. And what's the solution ?

Gidu
 
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