Will and Aikido Driver Stage work?

[bluegti]

Let me start by saying I have never built anything that was not a kit with specific instructions, so my question may not make any sense.

I want to build something from scratch. I've decided upon a power amp using a triode-strapped pentode (e.g., 6v6, el84, KT88 maybe). I have found lots of designs out there that have a "simple" driver stage based on half a 12au7 or 6SL7. I also found a few that are more complicated using SRPP, White follower, Mu follower, etc.

After reading about the Aikido circuit, I thought that it sounded like something I could try that would be a challenge, but at the same time flexible. However, I have not found any power amp designs that use an Aikido driver stage. Everything seems to be line stages, phone stages, etc.

What I really want is to build an amp with a volume pot, to Aikido driver stage, to single ended output. Is there such a design? Would it work? Is it a bad idea?

Thanks for your input.

[Cassiel]

Yes it will work, but four driver tubes for a 6v6 stereo amp?
Is it worth it? Probably not.

[leadbelly]

The drawback to using an Aikido to drive a power stage is that it does not offer a lot of gain. The gain of an Aikido is roughly 1/2 the mu of the front tube. If you try to overcome that by putting a high mu dual triode in the first position, then you get the drawback of high Miller capacitance limiting your bandwidth.

There is a "but", and that is that since you mention 6V6's and EL84's, these tubes will be easily driven to clipping by using a medium mu dual triode in the first position, so it's a not issue. However, a drawback to that is that a triode-strapped single-ended 6V6 or EL84 is only good for a couple of watts of power. If you can live with that, it should be pretty good!

As stalker says, if you are going to commit that many tubes to the driver stage, you could probably find something already designed that is a better all-around usable amp.

[athos56]

I use the aikido front end for both my Kt-88 amp and my hybrid mosfet amp. Both these amps can be found on the Tubecad site, along with a 300b amp. I think they sound great, good highs good lows. I use 6SL7's, 6SN7's, 12AX7's, 5751's, 12AU7's, 12BH7's. I think though I like the octals the best though. I think a Octal Aikido driving a PSE with 6V6's would be cool.

[Bas Horneman]

Is there such a design?

Yes

Would it work?

Yes

Is it a bad idea?

No.

There was this guy who posted a sligthly modified Aikido stage driving a 300B years ago. He won the best amp at diy gathering prize.

If I were you I would just go ahead and do it. One suggestion. For volume pot you might try the Lightspeed attenuator (apperently it is very good) plenty of info here on diyAudio. (I'm also planning a lightspeed attenuator for my preamp)