Mezmerize B1 Buffer Preamp

Hi Salas, I have a blue Mez board built up with 10R current setting resistors and wanted to briefly test the PSU section before soldering in the 4 matched fets...can I get away with not sinking the IRFP's for this test? Or will they heat quite quickly?
 
10K Log is not a bad choice. Personally I found it more on the contrast side than on the coherence side, at least with those pots I tested values back then.

Its not only about value but also what kind of pot material, total system synergy, preference. The available source equipment must feel OK on 10K loading is one other valid consideration.
 
Salas, just finished my Mezmerize B1. I want to thank you for all the help you gave me. It is replacing a regular B1 driving a F5. I was not prepared for this level of transparency and front to back depth. Just blown away!!! Thanks again, great work i appreciate your effort.
 
I'm guessing that I have done something wrong if the 2 x 5 groups of LEDs are not lit.
 

Attachments

  • DSC_0190.jpg
    DSC_0190.jpg
    985 KB · Views: 344
Last edited:
Even only one wrongly oriented or grilled during soldering is enough to break the chain. Fortunately you can test them before desoldering anything. A DMM that has enough voltage to turn on an LED in diode test mode or a 9V battery with two wires to briefly touch their pins at the bottom layer and see which ones light up and in what direction.

Also given the opportunity since you will lift the board, check again that the MOSFETS are the right types at the right sides as printed on the board near each one's pads.
 
Are the two MOSFETS near the lit triplets mildly warm? There should also be voltage drop already across the 18Ω resistor pairs at the sides of the reservoir caps. By the way, recheck that the BC550 is not a BC560 and vice versa while you are at it.

Good luck and let us know.