Good to see a DH-101 preamp and thumbs up on your fixes. I built the Hafler follow-on DH-110 preamp kit and Hafler eliminated the turn on thump by using J-FETs in the output circuit to mute the turn on/turn off thump.
Thanks so Much for your kind words and taking the time to share your experience with the DH110. I do have an upgraded DH101 that I may test at some point...
For those 4 gang, concentric shaft pots, what I've done a couple of times is to completely remove it from the unit, take it all apart (very carefully) then polish the spring wiper points with writing paper and thoroughly clean the carbon traces with alcohol. It's tedious work but it usually does get the thing back up and working.
You have a lot more patience than I do with regards to that kind of repair. I would only do that as a very last resort when there were no other options, just because I would be afraid that i would make things much worse. I was very happy with the results and solution I came up with. It was not until this week that I actually was happy to have a balance control for one of my systems.....
@@vintageaudioreview Your solution was just fine. If your friend is happy, then we should all be happy for him. I generally do have a ton of patience for this kind of restoration work. But no client would ever pay me for the time spent, so it's mostly for my own stuff. The last one of these I did was 10 years ago and (IIRC) took about 5 hours... would have cost a client about $200.
How do you test the RIAA compensation of the phono stage? You show a freq responce plot that is virtually flat. Does the QuantAsylum have a RIAA compensation built into it?
Thanks for the question and I am glad you asked one I can answer- yes, the QuantaAsylum has weightings you can apply, such as the RIAA, which makes it pretty easy to evaluate a phono stages frequency response. It also has A weighting, and you have the ability to add your own weighting file.
Good to see a DH-101 preamp and thumbs up on your fixes. I built the Hafler follow-on DH-110 preamp kit and Hafler eliminated the turn on thump by using J-FETs in the output circuit to mute the turn on/turn off thump.
Thanks so Much for your kind words and taking the time to share your experience with the DH110. I do have an upgraded DH101 that I may test at some point...
For those 4 gang, concentric shaft pots, what I've done a couple of times is to completely remove it from the unit, take it all apart (very carefully) then polish the spring wiper points with writing paper and thoroughly clean the carbon traces with alcohol. It's tedious work but it usually does get the thing back up and working.
You have a lot more patience than I do with regards to that kind of repair. I would only do that as a very last resort when there were no other options, just because I would be afraid that i would make things much worse. I was very happy with the results and solution I came up with. It was not until this week that I actually was happy to have a balance control for one of my systems.....
@@vintageaudioreview
Your solution was just fine. If your friend is happy, then we should all be happy for him.
I generally do have a ton of patience for this kind of restoration work. But no client would ever pay me for the time spent, so it's mostly for my own stuff. The last one of these I did was 10 years ago and (IIRC) took about 5 hours... would have cost a client about $200.
@@Douglas_Blake_579 But at the end of 5hrs, once it was installed and shown to work, you probably had a great feeling of satisfaction 😆
@@vintageaudioreview
Satisfying indeed ... but not profitable.
How do you test the RIAA compensation of the phono stage? You show a freq responce plot that is virtually flat. Does the QuantAsylum have a RIAA compensation built into it?
Thanks for the question and I am glad you asked one I can answer- yes, the QuantaAsylum has weightings you can apply, such as the RIAA, which makes it pretty easy to evaluate a phono stages frequency response. It also has A weighting, and you have the ability to add your own weighting file.