D-AOC PCBs - the building and help Thread

[The Unik]

Hi all,

After completing all tests and had a long burn-in for tubes as well as for audio transformers i confirm the quality of this compressor. I really love it!
Here are a few pictures.

Well done 

2 questions I f I may :

Is it the API 2621 trafos I see in there ? If yes where did you find them ?
Also is your front panel and case from Schaeffer (Front panel express)
Lastly, any clues to find those kind of panel meters ?

thx a lot

 

[MicDaddy]

Look like Sowter no?

 

[Unit-8]

MicDaddy you won!
Trafos are respectively the 9063 (ins) and 8940a (outs) by Sowter.

The Unik

Well done 

2 questions I f I may :

Is it the API 2621 trafos I see in there ? If yes where did you find them ?
Also is your front panel and case from Schaeffer (Front panel express)
Lastly, any clues to find those kind of panel meters ?

thx a lot

First of all... Thanks for appreciating my work!
You can buy the trafos online directly from Sowter's website.
Normally it takes 2 or 3 weeks for shipping, it depends on the availability or if they must build them from scratch.
Yes, the front panel comes from Schaeffer AG.
The meters instead are two NOS built in 1953 by Marion  Electrical Instruments Co. USA that luckily I found on ebay some time ago.

 

[felixnieto]

Just bought one of these units from a guy in Australia. Was wondering if there is a way to rewire the 240v input power transformer to 110v. or to just get a replacement transformer? Im trying to not have to get a step up box. I don't have too much experience in this department to know if its possible or not.

Any opinions?

 

[[silent:arts]]

Just bought one of these units from a guy in Australia. Was wondering if there is a way to rewire the 240v input power transformer to 110v.

We need to know which transformer you have.
Model or or Pic?

 

[felixnieto]

Alright. Here is a picture of the power transformer.

 

[felixnieto]

And one of the whole unit

 

[[silent:arts]]

Looks like the transformer has 2 x 115V primaries (yellow/white, orange/?)
Wire those in series for 230V.

 

[felixnieto]

Great! So I wired it up and you were right! Everything works perfectly! Thanks so much!

 

[steves.mastering]

Hi,

I haven't studied this project too much as of yet... just sitting in work at the moment and dreaming about how good this unit will be when it's done... or when it is started haha

I see a lot of people are enjoying this unit transformerless. I'm hoping to have mine switchable between Lundahls and transformerless.

Would this work similarly to the attached GSSL Mod?? Or would there be much of a difference.

Thanks all.

Ste

 

[MicDaddy]

I'm hoping to have mine switchable between Lundahls and transformerless.

I too am wanting to figure this out, also if an IC input option (also switchable), so you could go unbal, tx bal, IC bal on a switch, yay nay?

 

[Rocinante]

Im dying over here. Th his has been my Achilles heel.
Okay so first off
Im using the custom edcor with 230v, 9v, 24v
Upon power up everything glows nicely BUT the 470r 2 watt is just sooo hot. I replaced it with 500 ohm 25 watt and guess what; still hot. Way too hot.
I replaced every regulator and all diodes around them. They get hot but im using bog heat sinks to dissipate the heat.
Anyways the tubes glow nicely for about 2 minutes with the channel 2 12at7 a little bright then they just all start to die down at which point i quickly shut it off. I just bought 4 new 12au7 tubes just for this so it cant be them. I guess maybe the 12at7s but would they cause such overheating or the tubes to die down like that?
This has eluded me for forever now.  And to date is the only build i have had to put down and pick back up again a couple of times.  Its also my 7th tube project so i understand the basics and have had successes.  This has only been failure followed by failure.
Can someone please tell me where i can look?
By now its the point.

 

[Corusco]

I'm looking to finish my D-AOC up soon, but I've been slowed down for quite a while by not having  the time to draw up a slope selector circuit board. Would any who have designed one be willing to share their drawings for it?  Or if you have any left over from a board batch, would you be willing to share it?  I'm a little embarrassed having to ask, but it's been so long that I have to reconcile myself with the fact that I've gotten nowhere for a while because of it.

 

[Majestic12]

I'm looking to finish my D-AOC up soon, but I've been slowed down for quite a while by not having  the time to draw up a slope selector circuit board. Would any who have designed one be willing to share their drawings for it?  Or if you have any left over from a board batch, would you be willing to share it?  I'm a little embarrassed having to ask, but it's been so long that I have to reconcile myself with the fact that I've gotten nowhere for a while because of it.

I think I have a few boards left. Just write me a message.

 

[Jonkan]

After a long time of not doing any diy i finally decided to complete my d-aoc build. I'm wondering what to do with pin 1 of the i/o xlrs (I'm using the relay bypass pcbs from silent: arts).

Wire all pin 1 to chassi as close as possible to the xlrs? Or do i wire all the pin 1 to starground, where all the other ground connections iec/pcb/toroid are connected to chassis?

Also, does anyone happen to have a scale file for a round triplett dc 1 ma meter lying around that I could print out?

Thanks!
/j

 

[fragletrollet]

Where are people getting their VTL5C4/2`s from?

 

[Potato Cakes]

Where are people getting their VTL5C4/2`s from?

Try these guys:

https://octopart.com/vtl5c4%2F2-vactec-40913801


Small Bear Electronics used to carry them, but I don't seem them in their catalog anymore. Just VTL5C4's, not 4/2.

 

[yass.khay]

Where are people getting their VTL5C4/2`s from?

Try these guys:

https://octopart.com/vtl5c4%2F2-vactec-40913801


Just bought a couple here
[email protected]


Small Bear Electronics used to carry them, but I don't seem them in their catalog anymore. Just VTL5C4's, not 4/2.

 

[MicDaddy]

I used 1uF @ C102, C104, C105
Almost done, just waiting on the case from across the pond.

Still haven't finalized what to do with this HPF, or slope switch.

Also, I think I implemented the Fred Forsell pot incorrectly, or maybe I'm not understanding how you guys are using it because from what I see in the schematic of Fred's opto sidechain, it's not quite being used the same in this case for "matching"... I could be completely misunderstanding.

 

[chefducuisine]

Here is mine...

Thanks to Frank for the housing and his excellent engraving.