• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Poll..anyone interested in an Aikido linestage PCB group buy?

OK this ain´t the prettiest octal to noval adaptor you will ever see but it works!
 

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Maynard


I checked mine for the heck of it. With B+ of 218 volts I have 218 volts between pin 6 and ground of the 6N1P. I have 110.4 between pin 1 of the 6N1P and ground. I have 1.4 volts across my cathode resistors.

For the 5687 I have 110.4 volts between pin1 and ground. I have 4.34 volts across the 432 ohm cathode resistor.

Double check all connections and your heater connections.

protos

You have way too much time on your hands, LOL

It looks good!
 
Ok now I wait for the orders for this patented design.

Seriously though the trick is to get the small noval pins exactly placed and upright.Any small deviation on one pin will ruin the connection.
I am sure the more pcb software-literate members could churn out nice pcbs for this adaptor.I just used a dremel to cut the grooves and some jumpers on the top side.The pins are a bit short but thats what I had on hand that fitted.
 
MG

Glad to hear its up and running. I seem to favor the 6FQ7 into the 5687, Very smooth and detailed and better than the 6N1P was.
I had the same problem with the heater voltage being low so I went with two transformers

If your in the market for another line stage try the 6AU6 into the 5687. Its so fine.
 
Bas: any more PCB of the Aikido available?

Yesterday someone recommended that I build the Aikido so I ran a search and came up with this thread. Unfortunately I am a little late...

Are there any boards available?

Will more be made? Is the one made by John Broskie as good for 5687? Does John Broskie sell them? Can I use only 5687's? I have a box of them.

I have built the solid state Balanced Bride of Zen. Perhaps I've done something wrong - it doesn't sound very inspiring. Heard a friends tube preamp and was astounded at the dynamics.
 
B+

I have assembled my Aikido preamp (at least on a slab of MDF) to check out voltages. With the 2uF cap on the PSU board I see a B+ of ~255V. I removed the cap and put the 1uF cap in its place and see ~247V at R/L B+.

Do I need to tweak this closer to 220V or can I call it close enough? I didn't measure any of the other voltages since I wasn't sure it would be okay to have the B+ exceed the 220V by this much.

thanks,
Steve
 
Sheldon

I think SY is talking about the final board that John just received.
I emailed John several weeks ago and he wasn't ready to part with any as of yet. He did mention that some extensive tests were going to be made and I will make the assumption that SY is the one doing them. I wouldn't count on any pictures or information or anything being let out of the bag until all of the tests are complete and he is satisfied with the results.