DCB1 (Modified Pass B1 Buffer)

[Yomanze]

I'm not sure if anyone here has tried the Pass B1 Buffer yet? Have wanted to try one then this came along:

http://static.diyaudio.com/forums/gallery/data/1603/medium/SAM_0061.jpg

It's the Pass Labs B1 Circuit but it is DC coupled rather than AC coupled, it also has on-board discrete shunt regulators that'd work great with a center-tapped transformer! Something like an Hammond 15-0-15.

Anyway I've just signed up for the group buy for at-cost PCBs of $22 & made a small donation here:

https://spreadsheets.google.com/ccc?key=0AnAnd3RI56NmdGNRNjJ1M2d3eEd2Uzczb3ZyQkZRb nc&authkey=CI67lZ4P&hl=en#gid=0

DCB1 Article & PDFs / BOM here: http://www.diyaudio.com/forums/blogs/tea-bag/296-salas-dcb1-blue-edition.html

Thought I'd mention it as this will probably see off preamps costing £5k plus! The original B1 gets great reviews and that's with a wallwart supply & a cap on the output.

[Puffin]

I built a Pass B1 buffer (which I assume is the original?)

I use it with a Lightspeed Attenuator. Absolutely stunning. The Pass B1 is a lot simpler circuit and component count than the DCB1. I have a Mesmerize to build sometime???

http://i73.photobucket.com/albums/i239/saxonsex/B1Finished003.jpg

[Yomanze]

I built a Pass B1 buffer (which I assume is the original?)

I use it with a Lightspeed Attenuator. Absolutely stunning. The Pass B1 is a lot simpler circuit and component count than the DCB1. I have a Mesmerize to build sometime???

http://i73.photobucket.com/albums/i239/saxonsex/B1Finished003.jpg

Hi looks great! Haven't heard a bad thing about the B1. The extra complexity for the DCB1 is in the power supply (discrete regulators), so the actual B1 circuit for this design is totally faithful except for being DC-coupled. It looks like you've already got a serious power supply behind your unit already? The stock unit doesn't come like that ha ha.

If I do build it (am using an integrated at the mo) then will send it on!

[Puffin]

The Power Supply is a potted transformer from Avondale, bridge is 4 Q-Speed Diodes and a JLH Ripple Eater.

[HighFidelityGuy]

I have a DCB1 board waiting to get populated. I got it to experiment with as I was impressed by the design. I probably won't get it working for a while though as it's a low priority at the moment.

[Yomanze]

New group buy on at the moment, spreadsheet is here: https://docs.google.com/spreadsheet/ccc?key=0AnAnd3RI56NmdEJjMWtvWFVGdnkwUkcyQlB2dnIzS 1E#gid=0

Parts, PCBs as well as dedicated regulator PCBs. If you have seen the measurements of the Salas shunts on diyaudio.com then these are worth looking into, perhaps for the front end of an amp, phono & preamp supplies etc.

Some parts have arrived for my DCB1, which still hasn't been built as I've been using an integrated, until now...

[sachu888]

I have also built Pass B1 Clone,LDR and Regulated power supply.Its very good dead quiet very transparent.All boards have been made locally.
http://img213.imageshack.us/img213/5923/dsc04828q.jpg By sachu888 (http://profile.imageshack.us/user/sachu888) at 2011-12-24
http://img856.imageshack.us/img856/4135/dsc04970y.jpg By sachu888 (http://profile.imageshack.us/user/sachu888) at 2012-03-02
http://img853.imageshack.us/img853/4121/dsc04968f.jpg By sachu888 (http://profile.imageshack.us/user/sachu888) at 2012-03-02
http://img401.imageshack.us/img401/5246/dsc04969pr.jpg By sachu888 (http://profile.imageshack.us/user/sachu888) at 2012-03-02

Regards,
Sachin

[Puffin]

Nice.

[sq225917]

Used to have the original Pass sourced B1, nice sounding thing, a little light in the bass but great elsewhere. I have a Hypnotize board, ready fitted with quad matched 170's that i really am never going to build up, I should sell it I guess.

[Puffin]

You should build it.

Mind you I can talk. I too have a board, I also had all the bits before I plundered the bag for bits for other stuff.

:whistle:

[sq225917]

It's never going to happen, I had the B1, I haver a Krell KSP 7b already and as soon as the TNT man arrives today I'll have a new integrated so they will all be excess to requirements anyway.