My Aikido All-in-One octal preamp

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I wanted to share my Aikido build. Just finished it a few weeks ago. I am very happy with the sound! The tubes I chose to run are NOS JAN 12SX7GT.
 

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Very nice. I'm planning out my Aikido rebuild right now, just started measuring the boards and parts. It'll use FrontPanelExpress panels for the front and back, and maybe I'll go for their complete chassis. My Aikido is a 24v from the early days, with a Creek phono pre on a board, a Boozhound MC pre on a board, an International Power +/-24v linear power supply and my recently installed Welborne remote controlled attenuator/input selector that I built 10 years ago but never used. Right now it is a mess of a system, but it all works and is dead quiet.
 
zacster,

Thanks! It took me awhile to piece mine together and now that it's all together, there are things I would do differently (especially tidying up the wiring!). Now that I have it working, I can't bring myself to take it offline. All I want to do is listen to my music!

If you are looking at metal work, I used Landfall Systems https://www.landfallsystems.com/. They did a fantastic job! Plus it didn't take long to get my parts cut and anodized.

Good luck with your rebuild!
 
Hi Mike,
As a future project, I'd sit the transformers on a separate support bracket running front-to-back and then have a removable base cover that'll allow you to fix the top plate and drastically shorten/'neaten-up' those wires

With some careful 'maneuvering', you might even get the front pcbs/switches near the rear signal sockets with 'shaft extenders' - maybe some flexi-shafts needed to get around the transformers, etc .... - even on the Aikido, shorter wires are to be recommended
 
Hi Mike,
As a future project, I'd sit the transformers on a separate support bracket running front-to-back and then have a removable base cover that'll allow you to fix the top plate and drastically shorten/'neaten-up' those wires

With some careful 'maneuvering', you might even get the front pcbs/switches near the rear signal sockets with 'shaft extenders' - maybe some flexi-shafts needed to get around the transformers, etc .... - even on the Aikido, shorter wires are to be recommended

Thanks for the ideas, jameshillj. Towards the end of the project, I was just trying to get the thing done.
 
Mine is going to be fully remote controlled, so all the switching and volume control will be in the back. I've had a bit of a panic the last few days with it as I'm trying to tie all the pieces together with the single power supply.

The Aikido is 24v on B+ and 4x6v on the heater supply, so I run both of those off the same PS tap. Add to that that the Creek phono requires 24v (and also -24v) and the Boozhound runs from 18 to 24v. Also I've tapped it for a 5v supply to the remote control.

When I put the remote control unit on the PS I got lots of RFI noise, but after running for about half an hour it disappeared. I'm figuring that the tube heaters are picking this up and injecting it into the signal via the 5v tap. When I put the Boozhound on the PS I got hum, and it is dead quiet running on battery. When I put the batteries back I got screeching noise, but then I figured the batteries were dead, which they were. I'm going to experiment with this some more, but if I get hum I'll stick with battery. A pair of 9v will last about 6 months, unless I forget to disconnect them. Maybe I'll wire up an on/off relay of some sort that will work off the IR power cycle.

The attenuator is 3 stacked boards, one for the IR receptor, one for the input select, and one for the attenuator itself. The IR goes in the front, the other two can go in back. The wires are just controls, not signal, between the front and back. I'll put the MC and MM boards right at the back with a switch so I can easily select one or the other.

One thing I learned here is that proper grounding can make a huge difference. Separating the signal from the power from the chassis grounds keeps the hum at bay. Tying them at one point where electrons shouldn't flow except on a fault makes it very quiet.

I may leave the power switch in the back too. I have all my gear plugged into an Ankuoo Neo wifi enabled outlet, I no longer use the switches and just leave them all on and can turn it on/off from halfway around the world if I want, but mostly I never leave my couch.
 
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