Sold: KGSS Amplifier Transistors for the DIYer - incl 5 2SK389
Nov 11, 2008 at 5:41 AM Thread Starter Post #1 of 2


100+ Head-Fier
Oct 14, 2004
This post concerns the sale of all the transistors required to build Kevin Gilmore’s Current-Domain Electrostatic Amplifier for Stax Headphones. Popularly known as the “KGSS” amplifier. For reference, the design is specified here at Headwize: HeadWize - Project: A Current-Domain Electrostatic Amplifier for Stax Omega II Headphones by Kevin Gilmore. Note, I am also including spare pieces specified in parenthesis. So if I specify quanity 5 with 3 spare, two are required for the amplifier.

5 - 2SK389 Dual JFET (3 spare - these are out of production and very rare)
3 - 2SC1815 NPN Transistor (1 spare)
5 - 2SA970 PNP Audio Amplifier (1 spare)
5 - 2SA1156 PNP Transistor (1 spare)
5 - 2SC2240 NPN Low Noise Audio Amplifier (1 spare)
15 - 2SC3675 900V NPN High Voltage Amplifier (2 spare)
5 - 2SC2705 NPN Audio Frequency Amplifier (1 spare)
1 - 2SA1968 PNP transistor (0 spare)

I am asking $54.00 which includes shipping to anywhere in the US. They are all untouched by me and in the original sealed packaging. My guess the 2SK389’s are still very desireable and good money can be made from a pair if sold. For instance, they are also used in Kevin Gilmore’s popular Dynalo and Dynahi headphone amp designs.

To build the amplifier I can recommend two options. Either have your own PCB’s made or ask Justin at HeadAmp if he would sell you one. HeadAmp - Audio Electronics (Gilmore Electrostatic Headphone Amp [KGSS]). At the time my goal was to have my own built. If you choose to build your own I have all the gerber files required. I can give them all to you if you purchase the transistors. The files originate from the Head-Fi post...
Note I have all original documentation and pictures from Teucer’s posts and from his University of Texas files (linked within his posts).

Thanks for your interest.
Nov 11, 2008 at 9:05 AM Post #2 of 2


Headphoneus Supremus
Mar 31, 2008
If you can wait until I get home from work, you will be paid instantly. My feedback is below, also I have a thread here asking for these trannnys.
Thank you,

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