jamie

Sorry I have been late to respong (long week). It was $125, A good deal but immaterial as never sell it unless I find the balanced version to me these are sort of like collectors items in that really the 90's were sort of an interesting era quality digital audio it was pre-loudness war madness and I don't know I think one day I'll figure out how to hook it to my computer with out the spdif and all the c-mos before the pmd100-pcm63's , I've got an old Audiochemy DAC that I've owned for years also. I will check that. But here is a modern DAC same test setup. Its a NFB-12 with Wolfson 8741's. Now the noise floor is "nicer looking", I guess if Audio-gd does one thing right it is power supply, unfortunately look at how high the harmonic distortion is compared to the Parasound. I can't listen to the NFB-12. Just overwelhming harmonic distortion for my tastes (some may like it.) But I can't help but wonder if I could get the spikey noise floor of the Parasound improved that it would have a little smoother sound. Thanks for the info on the Blackgates, they being stock may be the issue (age). I guess I can try to measure they capacitance left in each of them, maybe I will get lucky and its only one or two that need replaced.

I picked up a Parasound 1100 hd at a thrift shop and found this website searching for info about it, I guess I should have opened it because the manual on the Parasound website is wrong. According to the manual it has 2 PCM63's per channel operating a push-pull output stage. I saw it didn't have balanced outputs but figured the manual was correct. Well it only has a single PCM63K per channel. It has an old high speed video opamp for the current conversion to voltage. I had bought it on the spot vagely remembering an Absolute sound article where they liked it as much as the TOL parasound and as much as any DAC at the time and I have always liked my friends Pass D1 which uses PCM63k's.. It is full of blackgate capacitors, I assume these are stock as it didn't look like anyone had opened it before. Sonically it is good in the midrange, bass a tad cloudy and the treble a bit harsh. I ran RMAA (Asus STX) and it has a nice flat frequency plot and low distortion, but there is an unusual pattern with the noisefloor. It looks like rectifier noise and its harmonics (see picture). Not sure if this is from old rectifiers radiating their noise, lack of filtering from the old electrolytics caps, or poor PSRR capability with the old opamps. Or is it jitter? Anyone have experience refirbishing/upgrading these parasound DAC's have a suggestion where to start ?