This is a review and detailed measurements of the "Finished Philips hifi forum tenth anniversary TDA1541 DAC Coaxial input L17-53." It was purchased on ebay by a member for $388.
Owner swapped out the fake TDA-1541A for a real one. This was a DAC design created for the tenth anniversary of hifi.net forum (?) and many vendors sell it online.
There are no markings anywhere on the device and only coax input is provided:
TDA-1541A Measurements
The DAC supports both 16 bit and 24-bit inputs even though the TDA-1541A only accepts 16 bits. Let's start with that input depth:
I reduced the input by 2 dB because the nominal output was 2.5 volt which is higher than 2 volt we are used to. It made a corresponding hit to SINAD as it is completely noise dominated. Distortion consists of 2nd harmonic at -102 dB or so which is very good for the era.
Switching to 24 bit input lowers the noise floor but raises distortion due to improper conversion to 16 bits (likely simple truncation):
Using the 16 bit input, the DAC barely escapes our poor category of DACs, ranking 260 out of 260+ DACs tested to date:
As noted, the problem is noise:
IMD test using 16 bit signal shows the same noise penalty but good distortion levels:
Jitter test shows many unwanted tones:
I did run the test with 16 bit signal and found similar level of interference.
Filter is rather slow with poor attenuation:
I could not my Multitone test even when I tried the 44.1 kHz sample rate one.
Conclusion
I was pleasantly surprised by the low level of the distortion in this TDA-1541A implementation. Everything else, especially noise level, is unremarkable to poor. I see nothing that indicates it would perform better than any modern DAC. Considering how much it costs, I can't think of a reason for such a device to exist other than audiophile myths around older DAC chips "sounding better."
Owner swapped out the fake TDA-1541A for a real one. This was a DAC design created for the tenth anniversary of hifi.net forum (?) and many vendors sell it online.
There are no markings anywhere on the device and only coax input is provided:
TDA-1541A Measurements
The DAC supports both 16 bit and 24-bit inputs even though the TDA-1541A only accepts 16 bits. Let's start with that input depth:
I reduced the input by 2 dB because the nominal output was 2.5 volt which is higher than 2 volt we are used to. It made a corresponding hit to SINAD as it is completely noise dominated. Distortion consists of 2nd harmonic at -102 dB or so which is very good for the era.
Switching to 24 bit input lowers the noise floor but raises distortion due to improper conversion to 16 bits (likely simple truncation):
Using the 16 bit input, the DAC barely escapes our poor category of DACs, ranking 260 out of 260+ DACs tested to date:
As noted, the problem is noise:
IMD test using 16 bit signal shows the same noise penalty but good distortion levels:
Jitter test shows many unwanted tones:
I did run the test with 16 bit signal and found similar level of interference.
Filter is rather slow with poor attenuation:
I could not my Multitone test even when I tried the 44.1 kHz sample rate one.
Conclusion
I was pleasantly surprised by the low level of the distortion in this TDA-1541A implementation. Everything else, especially noise level, is unremarkable to poor. I see nothing that indicates it would perform better than any modern DAC. Considering how much it costs, I can't think of a reason for such a device to exist other than audiophile myths around older DAC chips "sounding better."