Jadis defy 7 adventures

If there is anyone besides me on this forum that is using a Jadis Defy 7 amp and needs to know how to bias this amp, let me know. Good information on how to peform the bias procedure for this amp is hard to find.

I was able to fix my Defy 7. I had 8 blown cathode fuses and 1 open cathode resistor. I replaced the cathode fuses and the cathode resistor and installed a new set of GL KT-88 tubes. The bias is set as perfect as you can get with a Defy 7 which only has one bias pot for each bank of 4 tubes and you are shooting for an average of 4v across the 3 tubes in each bank. You can bet that I will be keeping a close eye on the bias by checking it regularly even though it is somewhat of a pain in the ass even if you know what you are doing. You also need a good DVM and a pair of 4 ohm 100 watt dummy load resistors.

The good news is that my Jadis is singing again and the GL KT-88 tubes sound great. I bought the tubes from Kevin Deal at Upscale Audio. They did a really good job of matching 11 out of 12 tubes but I had one tube that was "wacky" in comparison to the other 2 tubes in the bank of 3. I contacted Upscale Audio and they apologized and sent me a replacement tube that better matched to the other 2 tubes in that bank. The new tube arrived Friday and it is installed and all is well. I know some people complain about Kevin Deal, but I personally have had zero problems with him. Maybe because I always start my conversation by saying "I need to place an order for some tubes."

For some reason, Kevin seems to be a polarizing figure. I think he doesn't cotton to audiophile idiots that he perceives are wasting his time. Some people can get wacky with wanting a certain color label placed in just a certain spot on the tube and they want all tubes to have the same label facing the same way and on and on.

Sadly, it probably is.

Thanks guys. I actually had it up and running since June 18. I just had the one wacky tube that prevented me from optimally biasing the one bank of 3 but it still sounded fine. The replacement tube arrived on June 24 and now everything is really fine. I just hope it stays that way. When you are dealing with 50+ tubes in your system, there is always going to be something going on. For the here and now, my system is sounding great (to me at least). Sounds even better since I bought my Big Daddy pimp chair last Saturday.

Mark

Satch-I am lucky that I have a really good HVAC system. My room stays plenty cool in the heat of the summer and nice and warm when it is freezing outside. My brother usually wants a sweater on in the summertime in my room. Bottom line, I don't have to worry about the heat load from the tubes.

Mark