Doug Self Preamp from Linear Audio #5

if you have some free space you can putt near the power supply pcb a C-Core from Selectronic :

Transformateur R-core 14VA - 2 x 18V - R-CORE pour circuit imprimé

I'm not sure this one feet, I planned to putt an other one which has wired outputt I will screw close to the PS PCB with short connection from the secondary !
Transformateur R-core 30VA - 2 x 18V - R-CORE pour châssis because I have one already !

Maybe aUDIOPHONICS has some too, but check they have two separated secondaries (non common center tap gnd on the secondaries)
 
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I am fairly new to this, but these pieces look like they can be adapted to 230V.
Maybe someone more experienced can comment? :confused:

2x115V PCB Mounting Toroidal Power Transformers from Nuvotem Talema

I use 15VA Talema's (there are also Amveco). Looking at the AMGIS L01-6354 they are the same size and pin spacing. They are all dual primaries and dual secondaries. Just connect two primaries in series and you are ready for 230VAC. I just made myself a bunch of PCBs for these transformers with series primary connection for 230VAC use.

Regards,
Oleg
 
Finally!

Received all of the parts and assembled the preamp. The finished preamp is shown below sans lid (still being built) and without proper graphics.

This piece of kit is quite magical. It is inaudible at full volume with no inputs, and the clarity of CDs, particularly well mastered ones is remarkable. I haven't tried it yet with the vinyl but am expecting great things.

Thanks to Carl Huff for his superb boards and of course to the designer par excellence Douglas Self, and Jan Didden for publishing the design in Linear Audio #5. Of course DIYAudio is the glue that connects us all and provides the vehicle for dissemination and day-to-day discussions.

Graeme
 
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Nice Build. Clean Open layout. Is the Top going to be wood? Looks like you added led's to the selector switch board.? Well Done.

Thanks Rick. The top is to be timber - it's under construction. And yes I added LEDs to the selector switch: 5 red LEDs and 1 resistor on a bit of perf board wired to the switch board.

Still mulling over how to provide acceptable lettering on the front and rear panels.

Cheers

Graeme
 
And now adding pictures of the completed enclosure. Still no front panel markings. I am very pleased with this new piece of gear. It goes beautifully with my Salas Simplistic phono amp, so quiet and so clear. Joyce di Donato never sounded so good.

Graeme
 

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Hi,

I'm going to switch on the Douglas Amp pre but I'm nott sure of what I am doing with the I/O board powersupply !

So I need a little advise please.

I use single inded inputt and outputt : do I need to short the plug with a wire as I saw in some post or do I need to power it with the 17 V from the power supply board (or from the plug of the main board? ) ?

My understanding is this powersupply on the I/O pcb is a delay, but dunno when it is usefull or not and if this is for the balanced output only ?

Thank you in advance for your help,

regards

Eldam