B1 Buffer Preamp

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Joined 2007
Paid Member
KT,

I'll second labjr's comments. The reason I'm building the B1 is that Nelson's collective wisdom and knowledge is behind this design. My gut already tells me that I will enjoy the tunes that come from this preamp and I'll probably build a few more B1s just for fun.

I'll share this other tidbit with you. The guy who designed my amp worked at the local hi-end audio shop. With the blessing of his boss, he put this amp on the shelf with other well-known brands and smoked quite a few of them. That was back in '93.

I went back to the same shop 10 years later. I knew a couple of the guys and mentioned that my preamp was holding up well. They told me that it was solidly built, but that all the current designs were much better than the Aunt Corey's buffer and I could drop by for a listen anytime to compare. I didn't have the chance to do that but I could hear what was coming out of their demo rooms and I could definitely tell the sound was better than I had ever heard it coming from those rooms.

For me, if I had to choose between the B1 and Aunt Corey, I would choose the B1. Nelson created it, it really is easy to build for a DIYer and that makes it harder to do something really wrong. Plus, those PM buffers are no longer available.
 
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Joined 2002
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I had the "Aunt Corey"...and now; B1
The biggest issue with "A-C" is DC-offset & drift.
It will vary with temperature.
I had a DC-coupled amp, and could not live with it, and installed a cap on output...and in this configuration, the B1 bested the "A-C".
Whitout cap, it may have been 5% better...

Arne K
 
sonidos said:



If it helps, I bought a pair of PECs for the B1 and they do look awfully like what is pictured with Nelson's first photos of the B1. I believe Peter Daniel had started a thread some time ago that praised the PEC pots and I decided to give them a shot.

Let me know if you have any other questions and I'll be happy to answer when I get the chance.

Wondering which series of PEC pots you bought?
 
Thanks for the input, guys.

You've more or less convinced me that the B1 is the superior design. Although I have no experience listening to Mr. Pass' fine designs, his philosophy of simplicity meshes really well with mine, and I do truly appreciate his generosity with the DIY community. Based on the positive results all of you have had with the B1, it seems like a no brainer.

As I wait for the boards to become available again at passdiy.com, however, I've decided to go ahead and build the Aunt Corey circuit.

Arne's (Cobra2) observations comparing the two has got me thinking that the A-C may be worth a shot. And since I have the BUF-03s, regulator boards, and transformer on hand, I might as well give it a go.

The B1 will come later, though. I plan on setting up the chassis so I can switch in the B1 boards at a later time, obviating my concern about cost of a second chassis and associated parts.

Thanks for you input, and a big thanks to Mr. Pass especially.

Best,
KT
 
Member
Joined 2000
Paid Member
Nice build and why ignore the box

Thanks. The box is aluminum painted or coated beige with aluminum front and back. I got it at Mouser. Mouser has other extruded aluminum boxes that look nicer, but they run short width wise. It could be done but I like the short run of hook wires, like the Pass B1. This box cost $63, which for me is expensive for not liking it. I don't have acess to tools right now to make my own from plates.

BTW- the Radio Shack Rainbow wire is horrible. Don't use it if you don't have to use it. ;) I'll be rewiring with other hookup wire later. Right now I just wantto listen to something!

Also, I have another B1 90% finished. One of these will go to a friend.

Thx

V~