Aikido all in one with ps tube build

[moez]

Hello diyer,s just picked up an aikido all in one kit, the noval 9 pin, does anyone have any opinions in what tube selection would be best in a line stage configuration? Mr Broskie gives lots of options.

 

[leadbelly]

This has been discussed many times. How much gain do you need? That will impact your choice for the 1st tube.

6DJ8, 6CG7, 5687, 12AT7, etc are often mentioned. I'd probably use 6DJ8/6922/ECC88 as I have a bunch and they would do a good job in both positions.

 

[Einric]

I have used all 6CG7's and also a combination of 6DJ8 up front and 6CG7 in the back.
They both sound quite nice.

 

[kodabmx]

6N1P 6N5P is my favourite but 6DJ8 and 6N6P are good, too. The 6N3P is excellent if you get adaptors...

 

[Einric]

I have also used 6N1P's up front, they are nice, I used Svetlana "Winged C" variant.

 

[kodabmx]

They are nice, and also reflektor.

You can get the EV variant but I've used both and I don't find much of a difference...

 

[moez]

Thanks, I got some sylvania jan 6dj8 not being used Ill give those a try once it is completed.

 

[Steve Morley]

I built a version with four 6CG7 (300v B+) and didn't like it. Too tubey, slow bass. Changed it over to four 6DJ8 (150v B+) and liked it much more. See link to WoS article on Aikido 12Vac using 6DJ8s. Battle of the Cheap Line Stages – Part 1 | Wall of Sound | Audio and Music Reviews


Cheers, Steve

 

[moez]

glassware front panel board

Almost done assembling the aikido all in one with ps tube ,just waiting for some rca and a power switch to show up . coming from china might have to wait awhile .Thinking of installing some leds on the rotary switch to show what input its on any ideas ?

 

[moez]

Well the parts finally arrived . I will never order Chinese delivery again. better off staying with digi-key or mouser .I've decided to go with 6cg7 input and 6N23P-EV reflektor for output tubes also a 5u4gb for rectifier and a hammond pt 270ex . I don,t have a variac to slowly power it up so I want to be sure everththing is correct. Has anyone built this version of the aikido all in one kit , is there any incorrect info in the manual . any help would be great.

 

[PRR]

{snip}.... I don,t have a variac to slowly power it up....

Lamp Limiter!

 

[moez]

Yes thanks for that one ,just didn,t think of that I will put one together tommorrw .

 

[kodabmx]

You're complaining about waiting a month? You're lucky as I regularly wait up to 4 months!

I've built the circuit, not the kit but it was smooth sailing. If you are nervous you can connect the primary in series with a 100W light bulb. If there's a problem the light will glow bright.

 

[moez]

That the same as a lamp limiter as prr said

 

[moez]

I have question about the heater power supply section ,if I,am looking at this correct there seems to be some confusion in parts placement of the regulator adjustment r21,and r20 here is what i have. The image is my pcb which from the trace looks like r20 goes into the adjust on the regulator rather than r21. The second image is my user guide schematic , the third image I found on tcj site for this pcb . I think the pcb is not marked correctly. any help would be great thanks.

 

[moez]

Has no one here assembled this version of the aikido?

 

[kodabmx]

I build my Aikidos point to point... Has John not replied yet?

 

[moez]

No I give up, dont think he will. are the bags labeled wrong ,or the pcb , and which schematic is correct ?

 

[Steve Morley]

A few thoughts

Other than the hum does the amp work OK? I haven't built this board but I have built several other Aikidos.

One of your pictures from earlier shows that the inputs aren't connected, are they now?

All of the frames of the switches (attenuator, input select) should be connected to ground to prevent hum pickup. Try disconnecting the attenuator leads from the board then solder short pieces of wire across the board input points.

I don't think the ground from the power inlet is connected to the right place on the board. Shouldn't it be connected to HOUSE GND term near back of board?

Once a buddy couldn't get rid of hum until he connected an electrolytic cap across the film cap in the ground ref circuit, see attachment.

I've corrected one of your manual pictures as well, see attachment.

Steve

 

[moez]

I haven,t put power to the board yet ,yes the center star ground goes to the chassis and the house ground is connected to the iec . the B+ section you are referring to is done with a trace. I don,t want to put power to it until I know all is right.