Selling my DIY 9 W/ch mono class A Moskido amps which were my primary and best sounding amplifier for at least 10 years through various stages of parts and circuit upgrades. The Aikdio stage uses 7193 WWII radar tubes for about a 7X gain and 6BX7GT for buffered driver output configured for push-pull per John Broskie design. Some reviewers believe that the 7193 sounds at least as good as the very best 6SN7 tubes.
The next logical upgrade steps are to double the number of MOSFET transistors which would bring the power to 35+ W/ch and use a nice looking chassis. I have the extra needed MOSFETs, but transformers with more amps and a higher voltage would be needed. My DIY project days are coming to an end and I would like to let someone else continue this project. The Moskido design is still shown on the Mad Scientist Audio web site. If no interest, I hope someone would want to make a killer preamp with the 7193/6BX7 Aikido components. PM me with your questions and interest. Experienced DIYers only.
Included would be a box load of each kind of tube, Eagle files, schematic, a copy of the text from a DIYAUDIO forum MOSKIDO thread from 2007-2013 and all spare parts I have. Otherwise I will dismantle these amps and sell the parts.
The next logical upgrade steps are to double the number of MOSFET transistors which would bring the power to 35+ W/ch and use a nice looking chassis. I have the extra needed MOSFETs, but transformers with more amps and a higher voltage would be needed. My DIY project days are coming to an end and I would like to let someone else continue this project. The Moskido design is still shown on the Mad Scientist Audio web site. If no interest, I hope someone would want to make a killer preamp with the 7193/6BX7 Aikido components. PM me with your questions and interest. Experienced DIYers only.
Included would be a box load of each kind of tube, Eagle files, schematic, a copy of the text from a DIYAUDIO forum MOSKIDO thread from 2007-2013 and all spare parts I have. Otherwise I will dismantle these amps and sell the parts.
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A good price for me is what the used premium parts would sell for. My guess is $500 total for both amps with extras or $350 for all the Aikido components with extras plus shipping. This price includes vacuum tubes as free.
Premium parts are:
2 - Hammond potted 369JXP power transformers (Current price from the usual sources is >$300ea)
4 - 0.47uf Jupiter copper foil film caps (Current price PartsX is $99ea.)
2 – 65VA 0-18V, 0-18V R-Core power transformers (Cost me $48ea from China, no longer available)
14 – 6BX7GT and 16 - 7193 tubes purchased as NOS (Ave selling price on eBay about $10ea) plus 7193-to-6SN7 adapter for use with tube tester and the 6 tubes currently in the amps.
Other parts include Mundorf and Elna electrolytic caps, tx2575 and Caddock resistors, Hammond chokes, BUZ900/901 BUZ905/906 mosfets, etc.
Spare set of bare PCBs will help understand or troubleshoot the circuits. The bias PCB was designed to use SMD or through-the-hole resistors. I used Susumu RG SMD resistors. I will be available to answer all questions.
Theses amps sound great without the need for crazy expensive tubes made out of unobtanium. They do run HOT being Class A.
Premium parts are:
2 - Hammond potted 369JXP power transformers (Current price from the usual sources is >$300ea)
4 - 0.47uf Jupiter copper foil film caps (Current price PartsX is $99ea.)
2 – 65VA 0-18V, 0-18V R-Core power transformers (Cost me $48ea from China, no longer available)
14 – 6BX7GT and 16 - 7193 tubes purchased as NOS (Ave selling price on eBay about $10ea) plus 7193-to-6SN7 adapter for use with tube tester and the 6 tubes currently in the amps.
Other parts include Mundorf and Elna electrolytic caps, tx2575 and Caddock resistors, Hammond chokes, BUZ900/901 BUZ905/906 mosfets, etc.
Spare set of bare PCBs will help understand or troubleshoot the circuits. The bias PCB was designed to use SMD or through-the-hole resistors. I used Susumu RG SMD resistors. I will be available to answer all questions.
Theses amps sound great without the need for crazy expensive tubes made out of unobtanium. They do run HOT being Class A.
Attachments
I'm saddened to hear you getting out of DIY audio. I'd love to build a Moskido amp with your custom Aikido board. Do you still have the Gerber files handy?