hi all,
I have been looking for a decent but very cheap ADC solution for a while with limited success. What I need basically is analog to optical and/or coax.
- I know the Beis kit but 150eur+box+... gets a bit off budget
- Used interfaces? Firewire or too big or too expensive....
Before I surrender and end up buying one of those aliexpress 5 euros black little boxes (figuratively and literaly) wanted to ask you guys...
Does anybody know any of these?
Analog to fiber coaxial ADC sound signal to spdif Fiber coaxial digital signal to decoder|Personal Care Appliance Parts| - AliExpress
(They even share some measurements!! But not much more)
Analog Audio to SPDIF/Coaxial/Optical Fiber Output Board|Air Conditioner Parts| - AliExpress
What do you guys think? Any other suggestions?
Thanks a lot in advance!
I have been looking for a decent but very cheap ADC solution for a while with limited success. What I need basically is analog to optical and/or coax.
- I know the Beis kit but 150eur+box+... gets a bit off budget
- Used interfaces? Firewire or too big or too expensive....
Before I surrender and end up buying one of those aliexpress 5 euros black little boxes (figuratively and literaly) wanted to ask you guys...
Does anybody know any of these?
Analog to fiber coaxial ADC sound signal to spdif Fiber coaxial digital signal to decoder|Personal Care Appliance Parts| - AliExpress
(They even share some measurements!! But not much more)
Analog Audio to SPDIF/Coaxial/Optical Fiber Output Board|Air Conditioner Parts| - AliExpress
What do you guys think? Any other suggestions?
Thanks a lot in advance!
For the second one, you can see it uses a PCM1801U, so the PCM1801U datasheet should give you a pretty good idea how well it works.
The only cheap ADCs I have experience with were in little black boxes. They had a quite decent ADC chip, but the external anti-aliasing filter and driver circuit recommended in the ADC chip datasheet was nowhere to be found. At least the PCM1801U doesn't require an external anti-aliasing filter and driver circuit, so you can't have that problem.
The only cheap ADCs I have experience with were in little black boxes. They had a quite decent ADC chip, but the external anti-aliasing filter and driver circuit recommended in the ADC chip datasheet was nowhere to be found. At least the PCM1801U doesn't require an external anti-aliasing filter and driver circuit, so you can't have that problem.
Thanks Marcel,
Managed to find more pics of the first one, and with a very cool small black box, but doesn't really help to identify much on the board:
模擬轉光纖同軸 ADC 音頻訊號轉成spdif光纖同軸數字訊號到解碼器
Managed to find more pics of the first one, and with a very cool small black box, but doesn't really help to identify much on the board:
模擬轉光纖同軸 ADC 音頻訊號轉成spdif光纖同軸數字訊號到解碼器
I've used this one kebidu Analog to Digital ADC Converter Optical Coax RCA Toslink Audio Sound Adapter SPDIF Adaptor for Apple TV for Xbox 360 DVD|analog to digital|rca toslinkdigital to analog - AliExpress which uses the PCM1802. I thought it was pretty transparent.
The little black box with missing anti-aliasing filter and input buffer I wrote about looked just the same, but it had a CS5340 (and a CS8427 S/PDIF interface). The inputs of the CS5340 were just AC coupled to the cinch connectors through cheap and very nonlinear ceramic class 2 capacitors.
It was used at the local radio station here to digitize a signal coming from a DAC - which is inelegant, of course, but for some reason we couldn't just keep the signal in the digital domain. We got a soft but clearly audible tone due to a clock harmonic at the DAC output aliasing into the audio band. I ended up constructing my own filter and buffer circuit and then it worked fine.
It was used at the local radio station here to digitize a signal coming from a DAC - which is inelegant, of course, but for some reason we couldn't just keep the signal in the digital domain. We got a soft but clearly audible tone due to a clock harmonic at the DAC output aliasing into the audio band. I ended up constructing my own filter and buffer circuit and then it worked fine.
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So superior chip (I reckon) for 1/4 of the price of the 1801u board..... Hmmmm...
Is such a modification something a newbie like me could do if necessary? (already assuming all the little boxes are the same, that might not be the case but they all look so similar...) do you know where I could find any related info/instructions? Thanks a lot!
Is such a modification something a newbie like me could do if necessary? (already assuming all the little boxes are the same, that might not be the case but they all look so similar...) do you know where I could find any related info/instructions? Thanks a lot!
Apparently they are different, as Foxx510's little black box has a PCM1802 and the one I looked at had a CS5340.
It's a matter of screwing open the box, check what ADC IC is inside, comparing the circuitry between the cinch connectors and the inputs with what's recommended in the ADC IC's datasheet and modifying it as recommended in the datasheet. For a PCM1802, that would probably boil down to replacing the input coupling capacitors or doing nothing, depending on what you find in the box. For the CS5340, it's a matter of adding an op-amp and a few resistors and capacitors per channel.
It's a matter of screwing open the box, check what ADC IC is inside, comparing the circuitry between the cinch connectors and the inputs with what's recommended in the ADC IC's datasheet and modifying it as recommended in the datasheet. For a PCM1802, that would probably boil down to replacing the input coupling capacitors or doing nothing, depending on what you find in the box. For the CS5340, it's a matter of adding an op-amp and a few resistors and capacitors per channel.
Just in case anyone is messing with these cheap ADC boards, they output 96k SPDIF, not 48k as stated in the ads. If you need 48k I can confirm that changing the crystal to a 12.288MHZ sets it to 48k. The crystal in it was actually incorrect, a 24MHZ that should have been 24.576MHZ. The latest one of these I purchased has a knockoff CS5340 in it and what I'm guessing is a knockoff CS8406 SPDIF transmitter labelled NX8406.