Something I have been tinkering with for a while. This is basically your everyday TDA1543 NOS DAC except I put an inverter on the data line which flips the output phase. By using one chip inverted, I ended up with a differential pair. In hindsight, an Xor splitter might work slightly better, but this does the job.
In order to drive some headphones or long cables, I used a differential mosfet pairs and transformer coupled the whole thing. Since both sides are biased up the same amount (accomplished by carefully matching the mosfets, and then adjusting Vref a tad), no DC flows across the transformer. I also breadboarded a version without the mosfets using higher impedance transformers (Lundahl LL1930's) and even used as step-up devices, it worked pretty well with short cables.
There is also an ASRC. With these chips, this only seems to work at 44.1KHz, so I am just using the recovered clock from the receiver chip into the ASRC as a bit of a jitter reducer. Trying it with and without the chip, it does seem to help.
In order to drive some headphones or long cables, I used a differential mosfet pairs and transformer coupled the whole thing. Since both sides are biased up the same amount (accomplished by carefully matching the mosfets, and then adjusting Vref a tad), no DC flows across the transformer. I also breadboarded a version without the mosfets using higher impedance transformers (Lundahl LL1930's) and even used as step-up devices, it worked pretty well with short cables.
There is also an ASRC. With these chips, this only seems to work at 44.1KHz, so I am just using the recovered clock from the receiver chip into the ASRC as a bit of a jitter reducer. Trying it with and without the chip, it does seem to help.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
