Chinese pcb, 16 euros shipped from Hong Kong.
Replaced power capacitors (with tantalum caps) and coupling caps (with WIMA mks).
Case from an useless (here in Italy) power supply with UK plug.
I did new holes for 3.5 jack and usb.
I've also added a blue led light and four rubber feet.
http://recyclingaudio.blogspot.com/
Replaced power capacitors (with tantalum caps) and coupling caps (with WIMA mks).
Case from an useless (here in Italy) power supply with UK plug.
I did new holes for 3.5 jack and usb.
I've also added a blue led light and four rubber feet.
http://recyclingaudio.blogspot.com/
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Scarry view of those 230-240V prongs sticking out from your DAC
Oh yes I know but don't panic, we have no holes for that plug here in Italy
Hi,
I'm interested in such designs, I'm looking forward to an USB dac able to drive my earphones to listen at work (that onboard soundcard is not very good) .
Do you think this board can drive a 32 ohm headphone ? Or I will need to add an opamp to give it more juice ?
Thank you !
Thank you
I'm interested in such designs, I'm looking forward to an USB dac able to drive my earphones to listen at work (that onboard soundcard is not very good) .
Do you think this board can drive a 32 ohm headphone ? Or I will need to add an opamp to give it more juice ?
Thank you !
Thank you
According to the spec sheet of the pcm270x series chips, it can drive 32 ohm headphones.
Thanks I've missed the chip ref to google it for datasheet !
Ordered one this morning eBay | MINI PCM2704 HI-FI USB DAC DIGITAL BOARD SOUND CARD-XD , hope it will works great
Hi all,
Received it last week, with good packaging and wrapping.
It works as expected on windows 7 pro, the driver is automatically downloaded and installed.
It sounds ok but I'm a bit disapointed mine as some little but quite audible background noise (even with volume at 0 on windows). I guess it can come through the usb power line, or the cheap caps on it. I found people replacing power supply section with a less noisy one like this guy making USB DAC -- VICS USB Audio Kit(PCM2704) --
As for the capacity to power 32R earphones I'm assured it can be, output volume is very loud (at least on USB power mode, its rated 5vdc instead of 3.3 in case of a dedicated PS)
Does your present the same noise ? did you notice improvement after replacing the caps ?
Received it last week, with good packaging and wrapping.
It works as expected on windows 7 pro, the driver is automatically downloaded and installed.
It sounds ok but I'm a bit disapointed mine as some little but quite audible background noise (even with volume at 0 on windows). I guess it can come through the usb power line, or the cheap caps on it. I found people replacing power supply section with a less noisy one like this guy making USB DAC -- VICS USB Audio Kit(PCM2704) --
As for the capacity to power 32R earphones I'm assured it can be, output volume is very loud (at least on USB power mode, its rated 5vdc instead of 3.3 in case of a dedicated PS)
Does your present the same noise ? did you notice improvement after replacing the caps ?
Thanks for your reply.
I since try with a less sensitive headphone and the noise level is much more acceptable. The volume too, I can reach 10/15% on windows it isn't too loud.
I read these chips were originally made to drive power amps, and the line level may not be adapted to earphones (although output caps are).
Next I'll try to adapt output resistors to see if there's any improvement.
I since try with a less sensitive headphone and the noise level is much more acceptable. The volume too, I can reach 10/15% on windows it isn't too loud.
I read these chips were originally made to drive power amps, and the line level may not be adapted to earphones (although output caps are).
Next I'll try to adapt output resistors to see if there's any improvement.
I have the same USB mini DAC and to be honest, I expected a better sound. It is better than the onboard sound card but not what I expected. I need to replace the capacitors and put it in a box.
At the same time I ordered DAC with many inputs (USB, Optical, regular digital) and headphone amp called "Topping D2", and the improvement in sound is AMAZING. The instruments are very detailed and the music becomes addictive. The "Topping" cost me $138 shipped in 2 weeks from China to US. I connected it to USB and even 192 kbps MP3s sounded wonderful. I saw this "Topping" DAC for $123 once on ebay.
And this is how it looks from the front and from the back.
At the same time I ordered DAC with many inputs (USB, Optical, regular digital) and headphone amp called "Topping D2", and the improvement in sound is AMAZING. The instruments are very detailed and the music becomes addictive. The "Topping" cost me $138 shipped in 2 weeks from China to US. I connected it to USB and even 192 kbps MP3s sounded wonderful. I saw this "Topping" DAC for $123 once on ebay.
And this is how it looks from the front and from the back.
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