B1 Buffer Preamp

[6L6]

tinitus - This would be a very good use of Peter Daniel's PSU board...

http://www.diyaudio.com/forums/attac...m317-km337.jpg

[tinitus]

I really like the look of veroboards
and now is the time to try it
might be something like this
a lot of work for a couple jfets
but its diy, and having fun

[lolo]

Just completed the standard B1 with mundorf caps and integration in my system, with R2R volume control. Better and tighter bass, clearer highs. Little but nice improvement this far. A big thank for 6L6 for his tremendous help with cabling and grounding!

Cheers

Laurent

[6L6]

Laurent - My most sincere thanks, and a hearty congratulations on your completed project!


To those not familiar with Laurent's project, it is a single chassis implementation of a B1, a digital-controlled attenuator with front panel display, and the active crossover for the Linkwitz Orion speaker. Each module has it's own discrete regulated power supply. Wow!

[udailey]

Audio GD supplies. Nice
Thats a supply I would actually buy a board for, or the kit.
http://www.audio-gd.com/Pro/diy/PSU09/PSU09EN.htm

[tinitus]

Originally Posted by udailey

Audio GD supplies. Nice

looks like very skilled people
seems to be mostly plug and play stuff

but also a bit like they throw in a lot of components, just for the fun of it
but maybe it does make sense
I'm not clever enough to know anything about it
I like the KISS method better, for obvious reasons

btw, how important is low ESR caps, to the power supply in with a preamp
or maybe its even better to not use low ESR caps ?

[udailey]

I'm not saying you should go buy it, I was just recognizing the power supplies in that build 6L6 posted. I think they will supply max 800mA as is and up to 1.5A. Its actually about the same price to build than most regulator based circuits assuming you would put a sink on your regulator and use some decent caps for filtering. Uses 2sa970 and its counterpart as well as 2sc5170 and 2sa1930. BC639 I think to.
A lower ESR I believe will do a better job filtering anything that happens by that isnt DC. I think thats why lower ESR but I am probably wrong about that.
Any noise in the power supply can make its way into your signal in a preamp, since just like an amp active preamps modulate the supply rails.

[udailey]

6L6 I love the build, but dont you find that chassis supplier to have very low quality chassis? Mine didnt fit together at all. Was warped and screws did not match up perfectly with holes. Was completely disappointed with the purchase, frankly. 8Audio has very nice stuff in terms of quality.
Uriah

[tinitus]

Originally Posted by udailey

I was just recognizing the power supplies in that build 6L6 posted.

ahh, you are right, I see them now too

[lolo]

Hi,

I didn't think 6L6 would post the pictures, I would have made an effort otherwise and made some clearer ones!
I am a beginner in DIY and still have plenty to learn, forums like this one are really helpful.
I did use a Lite Audio chassis indeed, 59 euros here, and apart from 4 screws out of maybe 30 not fitting in the holes, I feel the quality is fair, you cannot obviously compare with chassis that retail for more, although I bought a chassis in France once for 80 euros that was absolutely rubish, returned it straight away.
I used 2 Audio GD PS, well spotted! they retail for 32$ and the build quality is good, it was a no brainer to be honest! But there are no measurements on their website so cannot comment on the performance, although they are very silent. I have an Audio Gd Dac and I am most impressed with it, they seem to specialize in overkill PS for all their designs, some of them having 13 filtering stages..

The B1 is hidden under the R2R volume control as I tried to keep everything close to the RCA and avoid long runs of cables.

Thansk again to everyone here.

Cheers

Laurent