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This Classified is Closed

For Sale:
Pete Millett Jonokuchi Headphone/Speaker Amplifer [Copper Base]

Will Ship To: CONUS

This is a one of a kind amplifier built by a professional engineer in the industry. The circuit is built out with Pete Millett's Jonokuchi PCB. Premium parts are used in the construction, and this unit has DC heaters for reduced noise and another tweak for the headphone output for silent operation. 


This amplifier features the 6EM7 dissimilar double triode that was originally intended for television use, but has lately found great favor in the audio community. The small half of the 6EM7 is much like half of a 12AX7 triode, while the output section is similar to an indirectly heated 2A3 triode. The chassis is machined and engraved copper, and they let it patina a bit to give the letters coloring, then cleaned up the top surface and sealed it with a polyurethane lacquer.

The circuit employs some nice tricks from Pete, while using nice transformers of well above-average quality. This amplifier will power speakers with about 3 watts per channel, so those of you with high efficiency Klipsch speakers will enjoy this feature. The headphone/speaker outputs are switchable via a button on the front panel, and there is one input on the back of the amplifier (RCA) and one on the front (1/8" mini) selectable by a similar toggle switch.

This is a beautiful little amplifier with outstanding performance, but I have too much gear and I'm working on building more, so I am making a bit of room in the collection. Worked great with Smeggy Thunderpants, K1Ks, and many other headphones and speakers.

Headphone Mode:
Gain: 11dB (150 ohm load); 10db (32ohm load) 
THD + N (at 1kHz): 0.28% (1V into 150 ohm load); 0.5% (1V into 32 ohm load) 
Max Output @ 5% THD: 4.6 V (150ohm load); 4V (32ohm load) 
Frequency Response (-3dB): 22Hz-28kHz (1V into 150ohm load); 22Hz-26kHz (1V into 32ohm load) 
Noise (Unweighted): 700 uV / 140 uV w/400 Hz High Pass Filter

Speaker Mode:
Gain: 10dB
THD + N (at 1kHz): 1.3% (1 watt into 8 ohm load) 
Max Output @ 5% THD: 4.5V/2.5 Watts into 8ohms
Frequency Response (-3dB): 24Hz-26kHz (1 watt into 8ohm load) 
Noise (Unweighted): 700 uV / 140 uV w/400 Hz High Pass Filter

Available upgrades:
Auricap Coupling capacitors - $25
Power supply conversion from CRC to CLC - $20
Cardas RCA jacks - $50


Graphs are not from actual unit but should be representative since they're of Pete's Jonokuchi amplifier/design. 

 

I have 2 barely used NOS GE 6EM7 from the late 60's and one that I haven't used (but should have a lot of life left)

 

Asking $800 shipped via PayPal. Buyer pays PayPal fees. Shipping on this is going to be outrageous as the copper base makes it incredibly heavy -- it probably ways close to 15 lbs even though it is pretty thin. 


Edited by gabbadabbadoo - 11/24/13 at 9:17pm