mwl168

Maybe that’s just the right-rear speaker of the surround-sound system.

My recommendation is to phase-in the changes. The safety resistors should be considered a must-do and replace all the capacitors as you have already did. I consider these 2 steps phase 1. I would then listen to the amp with the existing transistors for a while before moving to phase 2 - replacing transistors. I would take a few measurements of the working amp prior to changing the transistors and I may do it one channel at a time so you can reference between the two in case something does not work right. I would further break down transistors update into multiple sub-phases. This way, if something does not go as planned it’s easier to isolate the causes and trouble shoot. Also, preserve and keep the old transistors in case you need to put them back in. They are likely obsolete and unobtainable.

I think any good quality film capacitor, including the one in your link, should do fine.

Those 4.7uf are power supply bypass capacitors. The 4.7uf paralleled the 100uf electrolytic caps. I use some WIMA PP caps with appropriate voltage rating. And I used multiplayer ceramic caps for the .1uf.

Hi Chris: For my universal PSU (GRLV + GRHV), I use a Galaxy 3U chassis which comfortably accommodates the 680uf/550V capacitors. The chassis has no true finned heatsink, it has what the vendor calls the "quasi heatsink". I use this PSU to power my Carbon, Blue Hawaii, Grounded Grid and the CFA. I bolted the transistors of the GRHV to a L angle which is then bolted to the "quasi heatsink". Even powering the Blue Hawaii, which draws much more current than the Carbon does, the "quasi heatsink" only glows warm to the touch. I believe even if you just bolt the GRHV transistors to the bottom aluminum plate it should be fine - this is exactly what I did with my Megatron PSU which draws even higher current I believe.

None of the attachment seems to be working for me. Do others experience the same issue?

Happy Birthday!

This is probably stating the obvious, I would also position the input connectors to the opposite side of where the mains AC connector is and route the input signal wires along the chassis wall, far away from the transformers.

Don’t forget Kevin’s electrostatic CFA amp.

Looks good to me counselor. No need to appear!

Photos, we need photos, lots of photos!

What a disastrous qualification Ferrari had at Monza earlier today! Enzo is turning over in his grave.

Apologize if you already ruled this out - could it be the cable instead of the driver that actually died?

Did you check if the values are in stock with other brands like KOA, Xicon, etc.?

You have not idea how relieved I am to hear this. Thank you Santa!

May be better to post a picture to be sure but if the 8N80C you have are encapsulated then there is no need to use an insulator/plastic washer when mounting to the heatsink.

Happy Birthday Soren!

Thanks everyone for your patience. I did not realize so many of you have yet to receive the package. I sent the packages out in a few batches and usually 6 - 7 at a time. I am at a loss making sense why some of the packages arrived so much later than others.

The sad thing is that it appears that the Mouser delivery to me in USA takes longer than the delivery to a different continent.

@hhobeika The secondaries spec should be fine. You can dial back the current on the 15vac, 100mA ought to be enough for the Carbon front end which draws less than 20mA IIRC. B+/ B- draws around 80 mA both channel combined. 250mA should provide ample headroom. Where are you located? If you are in USA, you can check out Antek transformers which are well built, reasonably priced and sized.

Since I started trying different tubes on my SRX Plus I've noticed that, while the amp is dead quiet with some tubes, some tubes will result in audible hum with no input signal present. After some reading and experiment I decided the hum is most likely caused by leakage current between the heater and cathode of the input tubes. I decided to elevate the input tube AC filament supply. The photo below shows the filament elevation circuit I added this morning. The 12.6vac filament is elevated to about + 56VDC reference to ground. The amp with the same set of tubes went from a bothersome hum to dead silent (knock on woods)!

A very nice, different take of "The boys of the summer". Well recorded too.

Cut all the round holes myself with a table drill. The AC socket hole and the ventilating slots came standard on the chassis.

Cased my SRX Plus last weekend at long last. Finally got down to adjust and test it last night. The PSU inside is the Kerry design from the recent GB with a high tension supply timed delay.

I was warned by the USPS about possible delays when I sent the packages but did not expect the delay to be so extensive. Thanks for letting me know guys! I'll sleep a little better tonight.