![]() Output ports: 2 x Analogue Phono Ports (Left & Right).Input ports: 1 x TosLink (Optical Fibre), 1 x Digital Coaxial (Phono).The biggest issue was when I swept the digital input tone:This product has been discontinued and replaced by Part No 70468. Jitter disturbances are quite low but that is likely due to very high noise floor hiding them: Intermodulation distortion vs level shows that it does do better at max volume than a typical (low performance) phone headphone dongle: Low level linearity is lost due to noise: ![]() Someone forgot to enable the output filter (or implement one): ![]() Noise floor is high by our standards but good enough for the target application: This definitely impacts any headphone listening and makes it less compatible with devices out there. This puts the unit solidly in the "poor" category of all DACs tested: I hoped for 96 dB but got 85 dB SINAD (relative sum of noise+distortion). I would think if it is just a rebranded generic DAC, it would have come from China.Īs usual, we start with our Dashboard, feeding the DAC a 1 kHz digital tone: It is interesting to see full regulatory certification and manufacturing in Vietnam: As noted there are dual inputs (NO USB - USB is for power only):Īn RCA to 3.5mm adapter cable is included presumably for headphone use. I purchased it on member suggestion and costs US $14.Ĭan't expect more given the price and functionality. This is a review and detailed measurements of the Amazon Basics "192 kHz" Toslink optical and Coax input DAC. This one probably wouldn't pass muster as providing the true, magical 'NOS' sound, but frankly I find it difficult to care. Of course retro-tech audiophiles tend to go all-in on their obsession with obsolete technology, and most these days would insist that a 'NOS' DAC has to be R2R as well. ![]() A sigma-delta DAC that doesn't have a proper oversampling/shaped filter will display quantisation noise rising at 6dB/octave, which seems very close to what Amir showed here, so I suspect they're doing something similar. Obviously oversampling is happening further down the line, but it replicates the conceptual basis, though it's only interesting as a demonstration. There's a DAC design on DIYAudio that implements a 'NOS' DAC using a delta-sigma chip by bypassing the integrated first-stage filter. But the SAA7220 had a lot of problems with jitter due to coupling between the clock and filter supplies and some designers stumbled on the bright idea of ripping it out completely. The venerable TDA1541 that pops up is so many 'NOS' designs was actually designed to be used with the SAA7220 digital filter, which oversampled to 176kHz. In terms of the history of digital audio, such oversampling was introduced very early with R2R DACs. It's the first oversampling block that performs the alias-rejection filtering (and typically some noise-shaping). are welcome.Īny donations are much appreciated using : As such, I cannot recommend it.Īs always, questions, comments, recommendations, etc. In this site, my goal is to find best in class product and sadly, the Amazon Basics DAC is not it. No doubt it spits out sound though so as a "throw away" product, it works. Sadly they did not know to specify other important bits related to fidelity, resulting in a device that clearly could have been better but is not. I am sure that was part of the product requirement doc (PRD) Amazon gave to whoever designed this. There are some signs of quality here given the regulatory certifications and such. ![]() The DAC chip no doubt supports 192 kHz but there is no way to feed it such a digital signal. The mention of that in the product name is therefore improper. I tried to run the Multitone test which is at 192 kHz but could not get the unit to accept that over either Coax or Toslink. They have the room here to do a good job but obviously they did not to hit a cost target or didn't know better. SINAD drops to 50 at 20 Hz! Usually this is caused by poor power supply design. So we could "forgive" that but not the rise in low frequency distortion. The lack of filtering is the reason at high frequencies the graph goes off the chart (the green line at 96 kHz sampling reduces this impact). ![]()
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