Wayne's BA 2018 linestage

[pfarrell]

I'm sure there will be other recommendations...Not sure about "definitive recommendation" seeing this is all DIY, but...

Here's what I used (thanks 6L6):
DIY PCB - Bipolar (opamp) power supply | eBay

BOM at the bottom of this page:
LR Phono Preamp

Worked out perfect. Not too $$ to build. Has a fuse onboard—intelligent power switch setup—simple to add a power LED. Could have easily gotten 24VDC+/- out of it with resistor tweaks (R4, R6—values will not match due to circuit design). As is I tweaked it to around 18VDC +/-. It also fits in a 1U as speced in BOM as long as you use 1" heatsinks on the regulators.

513002B02500G Aavid, Thermal Division of Boyd Corporation | Fans, Thermal Management | DigiKey

See posts #919 and #932

 

[6L6]

All the PSU that people have used have worked very well. The link pfarrell provided is amongst the very best.

 

[nzlowie]

Thanks guys, appreciate it!

 

[6L6]

I agree with pfarrell, +/-18v seems to be the sweet spot for the circuit. But remember that it works beautifully on anything between +/-15v to +/-24v .

 

[nzlowie]

Finished the boards now waiting for PS board and parts. Re read a few posts and read something about setting trim pot, was I meant to do it before the boards were fully populated or do I just for minimum DC offset at the output?
There was comment that this method (DC offset) might not give the best result.

Correct or did I read it wrong? (Very possible!)

 

[Gooch]

Hello

Where can I get a set of boards to build?

 

[gary s]

I believe the DiyAudio store will have the new stereo pcb's soon. Perhaps Jim (6L6) can give us an update on when they will be available.

 

[nzlowie]

I'm sure there will be other recommendations...Not sure about "definitive recommendation" seeing this is all DIY, but...

Here's what I used (thanks 6L6):
DIY PCB - Bipolar (opamp) power supply | eBay

BOM at the bottom of this page:
LR Phono Preamp

Worked out perfect. Not too $$ to build. Has a fuse onboard—intelligent power switch setup—simple to add a power LED. Could have easily gotten 24VDC+/- out of it with resistor tweaks (R4, R6—values will not match due to circuit design). As is I tweaked it to around 18VDC +/-. It also fits in a 1U as speced in BOM as long as you use 1" heatsinks on the regulators.

513002B02500G Aavid, Thermal Division of Boyd Corporation | Fans, Thermal Management | DigiKey

See posts #919 and #932

So what were the values you used to set the 18V?

Cheers

 

[pfarrell]

So what were the values you used to set the 18V?

Cheers

Hi, if you look at the schematic he notes 13.7K for 15V (typo there, it should say “R6”)... I needed different values for each side to get the output more balanced, and I didn’t make proper notes, so you will need to experiment, but I recall that R4 was around 17K and R6 around 18K and change. You can see that I have a couple of resistors in series...

Report back on what you discover! Ha! I’ll make a note then.

 

[phomchick]

I started on this project a year ago and got about 70% done. I had all of the parts but only one of the two boards that I built worked. So somehow I forgot about it (or ignored it) for about 11 months. But I finally got back to it and a blast from a hot air rework station gun aimed at a suspicious looking SMD part got the second board working.

And finally, though it isn’t particularly attractive, it is done and it works.

 

[ilardi]

I think you are being hard on yourself. It actually looks quite nice to me. What power supply are you using? I am looking for something like that for another application.

 

[pfarrell]

I think you are being hard on yourself. It actually looks quite nice to me. What power supply are you using? I am looking for something like that for another application.

I agree! Looks great... give us some more details!

 

[phomchick]

I used this power supply: HIFI 50 watt 2-way linear power supply.

 

[6L6]

That looks great! Working and quiet is all that matters.

 

[Qwin]

Is there a picture of the Stereo board, plus board size and connection positions?


I'm starting a case layout design, while waiting for availability of PCB's.

 

[Qwin]

I found a picture of the prototype Stereo board that will do.

 

[Mr_Zenith]

And finally, though it isn’t particularly attractive, it is done and it works.

Looks quite nice to me. Neat and compact. Well done!

 

[citationfan]

Values of R3 and R6 on pcbs regard to schematics are different.
What are right values for R3(100 or 680 Oms) and R6(680 Oms or 1.5k )?

 

[william2001]

Schematic is correct.

 

[pfarrell]

Here’s a clear image of my boards before installation (and fixing a bad joint on Q2) for anyone needing a visual reference. I think this is the last board before final mods and production.