B1 Buffer Preamp

Pass B1

I feel a lil embarrassed here. Such a simple circuit and I cant trouble to get it working.
Here is a pic, can someone help take a look and see what maybe going on?

Much Appreciation-
TH
 

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It looks as though you are using the first set of inputs, but the bypassing of the switch connections is for the second input. Also, from your leads it looks as though you are testing the right channel, but the input volume pot is connected to the left channel, and I can't see the right channel connected.

Hope this helps.
 
Heresy, perhaps, but as I'm way to lazy to read the entire 406 pages of this thread and have a thick enough skin to withstand the heckling, here's a question - would there be any reason not to use a SMPS such as those by Mean Well etc intended for digital amps for a B1?

NES200-24 Adjustable 20-24 V 200W regulated supply $43
 
Interesting Attenuator.
But why give up the Balance function of separate Pots?
Used such for years and can't imagine a pre Without such an elegant balance ability

Because it can be a PIA to change the volume. I installed separate pots in my B1, and everytime I changed the volume I found myself fiddling with the pots to regain the balance I had before changing the volume. When I built my Mezmerize B1 I installed Glassware's A3 Mini Stepped Attenuator.
 
I agree it can be a PIA until you get the hang of using two pots but if you compromise with a dual pot the central point will be off to one side of the other. No two recordings are exactly the same and or your listening chair is off to one side. I like having the balance ability of two pots. I have tried it both ways multiple times and I like having two pots much better. Anyway I need the exercise of getting the central point exactly to my liking.

It can come down to how much you are willing to sacrifice not have vocals exactly centered. I get irritated when vocals are too far to the left or right.
 
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Because it can be a PIA to change the volume. I installed separate pots in my B1, and everytime I changed the volume I found myself fiddling with the pots to regain the balance I had before changing the volume. When I built my Mezmerize B1 I installed Glassware's A3 Mini Stepped Attenuator.

Erm. IF.. there are sophistications such as markers/numbers on the dials or unit face.
Then..it's a fair No Brainer to match the numbered positions ;)
Ersatz Balance using 3 pots is an old (and proven) idea.
Can't believe it's actually necessary.
That glassware gizmo looks as a bit Agricultural.
Does it perform better than the schematics' suggested Pots ?
Not that I'd fit one, Mere curiosity..is all.
 
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Erm. IF.. there are sophistications such as markers/numbers on the dials or unit face.
Then..it's a fair No Brainer to match the numbered positions ;)

Mine had numbered positions, but the adjustments were very fine to try and get the right balance. I probably should have used a higher value pots.

That glassware gizmo looks as a bit Agricultural.
Does it perform better than the schematics' suggested Pots ?
Not that I'd fit one, Mere curiosity..is all.

So far, I am happy with it. Balancing doesn't seem to be such a chore as it was with dual pots. I have only been using it for a few weeks so maybe the novelty will wear off after awhile :p
 
Working on my B1 Buffer now. I need to order three 1uf caps and Nelson Pass says in his DIY PDF that he uses three of Digikey BC2076-ND for C3, C100 and C200.

However I've seen it recommended to just use the above cap for C3 and get the Jantzen 1uf caps from Parts Express for C100 and C200.

(http://www.parts-express.com/jantzen-audio-10uf-400v-crosscap-capacitor--027-910)

Which way should I go?
 
The Jantzen are likely to be bigger. Check they will fit the pin spacing on the board

Yeah they are bigger. I'd have to leave the leads extra long and angle them down into the holes.. the cap would be sticking up like 1/2" higher than the board. Don't know if this is okay or not. But is it worth it sonically speaking? The Jantzen sound better than the ones Nelson Pass recommended?