Laowei

Very nice!

From the experience on my past tube amps, by habit on my KGST build, I tightly twisted all paired wires. The result is it is dead quiet operation. Now I am wondering how best to dress the wires between amp PCBs outputs to the Stax jack. Not sure what is best practice driving e-stats. Right now on my build they are twisted too, which would minimize capacitance in the pair. Scatter wired pairs would maximize capacitance. Maybe paralleled wires like the Stax cord would be the theoretical best?

Just wondering if you noticed a change in SQ when using the Stax extention.

http://www.mouser.com/Search/ProductDetail.aspx?R=T93YA105KT20virtualkey61330000virtualkey72-T93YA-1M T93YA is what you need. Trim screw on top, and pins in a row on the bottom.

Built it to 350V like you did. It settles in at +349 and -358. The non symmetry does not bother me as the tubes cathodes are sitting around 23V off the negative rail anyway.

ATM long term temperature monitoring mine while listening. The heatsinks opposite side of the CCS are running 130-134F. I'll probably go with a cutout in the top plate and screen mesh insert above the tubes and heatsinks and see how that works out. Agree that the KGST is a very special amp. Can't turn it off if I start listening. Many thanks again to Kevin and Birgir for the original design and development. And to Geoff for the PCB group buy.

Congrats on the nice build, Insanity!

Please post a link here.

Try Mouser. http://www.mouser.com/ProductDetail/Kycon/KUSBX-BP-KIT-SC/?qs=sGAEpiMZZMulM8LPOQ%252bykzAp4yt8IxVbGCTGRemOe8Q%3d

Then I must have a pumpkin head. On my recently purchased 009s, over several days I had to bend the fuck out of the arc to get them to do proper bass. They now are sitting very light on my head and ears, especially since I am coming from LCD-3s. The 009s are playing wonderfully with my KGST now.

Yeah, just give them a Spritzer Thump.

Try Mangler here or on that other site. Last I heard he had a set for sale for $30 +S/H.

Nice build.

Actually not. Shuguang in Tianjin north China, first started with their premium Treasure tube line a few years ago. A number of the engineers that were responsible subsequently left and started their own Psvane company originally in Guangzhou south China. I believe they may have since moved to Tianjin.

^ Can't argue with doing it right.

What I did with my 8mm thick front panel: >Drilled 9mm diameter thru. >Counterbored 19mm diameter minimum x 3mm deep (leaving a 5mm length of the 9mm hole). This is for socket clearance to tighten the installed washer and nut. And modified the Alpha pot by taking a wire cutter to the little piece that sticks up from the mating face. It is there to go in a matching hole in the front panel to stop the pot from rotating. Not really needed if you tighten the nut securely.

FWIW, another data point to add: Got my new SR.-009 last week. Also purchased from PriceJapan. Also no channel imbalance.

Thinking this thru, the 24V Zener clamps the voltage across the grid and source of the FQPF 8N80C. The grid will only draw minor current if the zener's breakdown voltage is exceeded. On second thought 1 watt should be fine.

Took me a while to troubleshoot my latest problem. I found the 24V 3W Zener on the output mosfet failed, shorting out the +350VDC supply. Symptoms were a slow ramp up of B+ voltage with the PS disconnected to the channels, and no B+ when one or two channels connected. B- was unaffected. The 3AT fuse did not blow, as the CCS regulated the current to the short. Looking now to replace the Zener. Locally, I've found 1watt and the physically larger sized 5 watt. Will 1watt be adequate, or should I order a 3watt from Mouser and wait a week for delivery?

Thx.

How do the Stax electrostatic headphones scale with voltage? For instance, a model's sensitivity is rated at 101dB@100VRMS at 1khz, if the voltage is doubled is there a 6dB increase of SPL?

Oh my!

Nice! A real mini BHSE.

WOW! Super nice work!

Measure the voltage across each zener in the string with the power on. Turn it off and let the HV capacitors settle. Replace the highest measured 100V zener in the string with a 91V zenner. Power up and remeasure for 350VDC output. Repeat replacing the 91V zener as necessary to get desired PS output voltage.