Grounded Grid vs. Aikido

[korneluk]

Anyone done an actual listening comparison of an Aikido preamp vs. the Transcendent Grounded Grid?

I am not related to either manufacturer and do not favor one or the other, just looking for your impressions.

-- josé k.

 

[jayme]

I built the Transcendent Sound Grounded Grid in kit form. It sounded great. Well worth it for the money, and extremely easy to put together.

But, I have to say that my just-completed scratch-built Aikido is much better. The clarity is outstanding.

 

[korneluk]

[tube selection] Aikido vs. GG

The GG uses 12au7s - what tubes did you use on the Aikido and what is the B+ voltage?

Thanks,

 

[jayme]

I used 6SN7 octals for both stages, and I can vary the B+ between 270V and 330V by using different tube rectifiers.

Also, I didn't use any electrolytic caps, even in the PSU. Just some big 15Hy chokes and ASC motor run caps.

 

[Cobra2]

Great!

I will soon start building a 6SN7 Aikido myself...

Would you mind sharing more details of yours?

Arne K

 

[jayme]

Well...one thing is for sure...I didn't skimp on parts for this Aikido project. The difference I hear *might* be attributable just to the better parts list...but I personally feel the circuit topology has more to do with the excellent sound than the parts.

My Aikido used Bas's boards, as I ordered them before Broskie was selling his boards.

I used Lundahl iron throughout the PSU: a mains transformer and 15H chokes in a CLCLC configuration (the last LC is parallelled: one per L/R).

The 6SN7s have AC on the heaters, biased to around 90V with a 330V B+.

The output coupling caps are .47uF Auricaps. The resistors are Kiwame resistors (well...the ones that matter, anyways).

My favorite part is that I mounted the boards on 2" standoffs. This allowed me to run shaft extenstions underneath the boards to the volume pot and selector switch which were mounted at the back near the inputs.

And, the chassis is steel.

At around 30lbs, it is certainly a heck of a lot heavier than the 5lbs that the Grounded Grid weighs in at...

 

[Cobra2]

Nice!

May I also ask for the Lundahl part-numbers?
(forgive me, I'm fairly new to tubes in audio)

Arne K

 

[jayme]

Of course. The mains is LL1683 and the chokes are LL1673. They are a bit pricey, but of such high quality and performance that I find them to be a bargain.

 

[JoshK]

Jayme,

As always, I find your work top-notch. You should come by our GTG's sometime, or just come by my place for a little listening & shootin' the sh**.

I always wondered why better iron in the PSU made any difference. Is it the DCR? Less reactance? .....

I am working on an octal aikido myself. I was thinking of 12sx7 followed by 6bx7's. I have nine pin boards from Bas, which I was thinking of 6cg7 > 6h30pi (or something to that tune). What'ya think?

 

[Burnedfingers]

Well...one thing is for sure...I didn't skimp on parts for this Aikido project. The difference I hear *might* be attributable just to the better parts list...but I personally feel the circuit topology has more to do with the excellent sound than the parts.

I have built a number of Aikido line stages. Some I have used high quality parts and some I used run of the mill parts. Some were point to point wiring and some were Bas circuit boards or boards from JB. I also built several grounded grid line stages.

In my personal opinion I believe the Aikido to be superior regardless of the parts used. I have also done A/B tests with friends to see which they would pick. The Aikido has been the winner.

 

[jayme]

I always wondered why better iron in the PSU made any difference. Is it the DCR? Less reactance? .....

I am working on an octal aikido myself. I was thinking of 12sx7 followed by 6bx7's. I have nine pin boards from Bas, which I was thinking of 6cg7 > 6h30pi (or something to that tune). What'ya think?

I really like the 6SN7s, but they have too much gain in my system. I'm thinking about picking up some 6BX7s and even some 6AS7s/6080s to try as the input tubes. Should be interesting to try a preamp with unity gain... Thankfully that Lundahl mains has the current capability to drive them.

As long as you can deal with the gain, the either combo you list above will sound wonderful.

And, well, I like the big iron for the extra smoothing, and frankly the lower overall capacitance it allows. When I ran a bit lean on the capacitance, the preamp sounded awesome, but I had a heck of a turnoff thump and a rather disturbing LF (inaudible) motorboating.

Definitely let me know about NYC-area get-togethers...seems there are a number of us in the area on this board...