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

[2wo]

Hi Steve,

The ecc99 and the 5687 are not pin compatable.

You need to rewire pin 6,8 & 9... John

 

[SteveA]

Hi Steve,

The ecc99 and the 5687 are not pin compatable.

You need to rewire pin 6,8 & 9... John

Hi John-
I had a second set of boards and wired them for the ecc99 according to Bas' manual (I think). If I read the manual correctly, the heaters need to be wired (with 6.3 V xo) 4 and 5 joined and one 6.3V lead connected there; the second 6.3 lead going to pin 9 (instead of 8 as with the 5687). And ,of course, I used jumpers 3 and 5 instead of 4 and 6. I believe that accomplishes the rewiring needed. Is this correct?

My voltages at the various points (with the 6N1P/ecc99 combo) seemed much more in line with those listed on the schematic.

I'm thinking of asking Bas if he has any more boards. Then I could wire a set for all the remaining permutations (as far as heaters are concerned).

Probably better get one up and running first.

I will probably get a cheap (RS) pot and fire up both versions and see how they sound (hopefully there will be sound).

Thanks,
Steve

 

[rick57]

Making Aikido happy with Amity

Hi,

I have Aikido PCBs from this group buy (exact use to be decided & populated), which I am hoping to use in a semi active hybrid horn system that’s now mostly “locked down”.
To drive the horns covering 150 – 750 Hz, I’d like to use the Baby (petit) Amity, the 2A3 version of Olson's push-pull Amity.

Lynn Olson warns at www.nutshellhifi.com/triode1.html that:
“Although the Amity is a beautifully simple design, it makes severe demands on the preamp. The preamp has to drive the combined capacitance of the interconnect cable, the input transformer, and the Miller C of the input tubes.
This can easily add up to 200 to 600 pF of capacitance, depending on how long your cables are and if you choose to use a 1:2 step-up in the input transformer (which quadruples the 100 pF Miller capacitance of the input tubes).
In all honesty, this is a difficult load for most tube preamps, with 12AX7 cathode-follower preamps falling down the worst. (1 mA cannot drive 600 pF!)
Preamps with 12AU7 cathode-followers aren't much better, sounding very 'tubey' rolled-off, and old-fashioned”

I confess I’m not clear if Bas’s PCBs use cathode-followers. If so, my reading of John Broskie says they’re an unusual kind of cathode-follower.

The interconnects were likely to be about 3m, though I could get them down to say 0.8 m. Are there other things I need to do, e.g. part values (?) to make the two work happily together?

I have little time to experiment, so if they’re not likely to work well, I’ll probably look for a 2A3 PP without cathode-followers (any suggestions there)?

Thanks

 

[Bas Horneman]

I confess I’m not clear if Bas’s PCBs use cathode-followers

The problem Lynn has with a preamp is not so much a cathode follower I think..but rather 12AX7 and 12AU7 cathode followers.

The Aikido output is a cathode follower. But if you use an ECC99 or 5686 or 6N6P for instance..you will have no problem driving the Amity.

One guy even reported that for some reason..the Aikido LOVES a difficult load.
"The most amazing thing is that when presented with a load, it just wants more. Distortion goes down with heavy loading. Why is that?"

http://www.tubecad.com/2005/January/blog0032.htm

The proof of the pudding is in the eating however. Theoretically the XPP (also described on tubecad) would be even better.

Regards,
Bas

 

[Bas Horneman]

By the way...is there still interest in an Octal PCB? The Octal PCB has been tested and works.

Regards,
Bas

 

[Burnedfingers]

Quote:

By the way...is there still interest in an Octal PCB? The Octal PCB has been tested and works.

Regards,
Bas


Right on Bas! Bring it on!

 

[rick57]

Bas

Thanks . . 😎

Of the ECC99, 5686 or 6N6P - what are best in which circumstances? ~ or has this been covered?

eg for punch & clarity over only 150-750 Hz which would you tend favour

And any advice re Lynn’s ‘1:2 step-up in the input transformer’?

Thanks again

Cheers
🙂

 

[Burnedfingers]

Quote:

And any advice re Lynn’s ‘1:2 step-up in the input transformer’?


If I may ask...why do you need a step up input transformer? There is way more gain than you will ever need. I'm a gain freak and even I am satisfied with it.

 

[Bas Horneman]

and if you choose to use a 1:2 step-up in the input transformer

IF you choose a 1:2 stepup....

IF.Lynn states....

best would be to use a 1:1 input transformer as he himself has done with the Amity, or even a stepdown 2:1. At the moment I am planning to one day do an Amity with the Cinemag 15/15b (using resistors to create a CT)

Of the ECC99, 5687 or 6N6P - what are best in which circumstances? ~ or has this been covered?

You can add the 6H30 and quite a few other here as well. Which is best...I suspect has to be determined by you..for your tastes...one likes the ECC99 the other 6N6P..the other ....xxx.

eg for punch & clarity over only 150-750 Hz which would you tend favour

Can't say I have listened that much to either of those types...so far only in the Aikido..and my system has only briefly had them in my system....and could tell you even less about that small part of the auditory spectrum..

 

[harwoodspark]

Octal PCB

By the way...is there still interest in an Octal PCB? The Octal PCB has been tested and works.



Hi Bas. I'd be interested in a pair of octal boards. Would the PSU be similar to that used for the other boards given the higher voltage required for an octal Aikido. Thanks, Si.

 

[Bas Horneman]

Would the PSU be similar to that used for the other boards given the higher

Basically..the PSU boards are pretty generic... you could easily use them to create a b+ of 300V...if everything is within spec for the caps/resistors etc.

 

[Burnedfingers]

Bas,

Make my count 4 please.

 

[hifryer]

I am very interested in boards for Aikido. Preferably Octal for 6SN7.

I have been waiting to hear from JB as he promised boards or a kit. But nothing from him after a long wait.

How do I go about getting some boards?? Will consider 9 pin etc if necessary.

Also what is the consensus re listening tests?

Sorry if this info buried in 50+ pages of posts!!

cheers

 

[Bas Horneman]

I have been waiting to hear from JB as he promised boards or a kit. But nothing from him after a long wait.

Good things come to those who wait. I think they'll still come out.

But good things also come to those who want an instant fix. 😀

How do I go about getting some boards?? Will consider 9 pin etc if necessary.

Right now..I'm just measuring interest...in about a week or 2. We'll close the groupbuy. I wait for the boards...and receive payments. (preferably paypal). After payments I ship them to you.

Also what is the consensus re listening tests?

For the 9 pin boards (which are the only ones we had thus far)...the 6CG7 was quite popular. But suprisingly few people have come back with building and or listening reports.


Just a recap of what the octal boards look like. Layout slightly improved over the 9pin I think...with a better earthing arrangement.
Compromised URL removed by Moderation

 

[Burnedfingers]

Bas,

What is the per board cost going to be for the octal boards?

Thanks,
Joe

 

[Bas Horneman]

Hi Joe,

They will be the same as the nine pins. 9,50 US$

Regards,
Bas

 

[bst]

Hello Bas,

I'd like to purchase eight each of the nine-pin and the octal boards (total of sixteen). Please let me know if you'd like payment in advance to facilitate production.

Thanks,

bst

 

[Bas Horneman]

I'd like to purchase eight each of the nine-pin

I suppose we could do a batch of 9 pins as well. Let me speak to our board man.

no Pre-payment necessary.🙂

 

[2wo]

Hi Bas,

I would like a pair of octel boards and a PS board if one was available...John

PS here is a shot of mine, 6n1p-6n6p. Everyone who has listened to it has liked it

 

[Bas Horneman]

Hi Bas,
PS here is a shot of mine, 6n1p-6n6p. Everyone who has listened to it has liked it.

I suppose that includes you?😉

No PS boards left....might order as well.