Does anyone have any experience with the new Akita 12V preamp? I am thinking of using with a Peter Daniels LM3875 chip amp.
New Aikido 12Vac PCB and part kits
New Aikido 12Vac PCB and part kits
I'm upsizing to 24vac that should yield about 180vdc.
http://www.diyaudio.com/forums/tubes-valves/235901-aikido-12vac-2.html#post3603908
http://www.diyaudio.com/forums/tubes-valves/235901-aikido-12vac-2.html#post3603908
The heaters are depicted on the schematic below as four 74 ohm resistors in series with a 68 ohm dropping resistor. Simulation shows 2 watts being dissipated in the 68 ohm resistor.
With the 18vac version, there is a 10 ohm resistor and barely enough voltage on the 12.6v heaters.
As far as the aikido circuit itself, you will want to change cathode resistors to shift the operating points.
With the 18vac version, there is a 10 ohm resistor and barely enough voltage on the 12.6v heaters.
As far as the aikido circuit itself, you will want to change cathode resistors to shift the operating points.
Attachments
Filament voltage derived from the spot I marked "X" and the negative voltage probe (black colored) shown below with ripple expected. 68 ohms drops it to about 48vac across the 4 series filaments with even less ripple due to the RC filter of R11 and C10.http://www.tubecad.com/2013/03/blog0258.htm
For an in-depth review from the designer himself of this sextupler circuit, refer to his blog:
http://www.tubecad.com/2013/03/blog0258.htm
For an in-depth review from the designer himself of this sextupler circuit, refer to his blog:
http://www.tubecad.com/2013/03/blog0258.htm
Attachments
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Anyone know which tube/voltage option would play better with a Gainclone amp? 6DJ8's provide a gain of 15db, 12AU7's a gain of 9db. I believe the Gainclone chips all run at a minimum gain of 10db?
I was thinking about 6DJ8's @ 15db and a LM3886 @ 15db for a total of 30db. Too much for an 'integrated'? Am I missing something about how these would interact?
Tubecad 12VAC article if everyone hasn't already found it.
I was thinking about 6DJ8's @ 15db and a LM3886 @ 15db for a total of 30db. Too much for an 'integrated'? Am I missing something about how these would interact?
Tubecad 12VAC article if everyone hasn't already found it.
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