B1 Buffer Preamp

I understand the b1 provides no voltage gain and is all about impedance matching but in several places in this thread I see references to added drive like a pre. Does the b1 provide more current?

You may not be conceptualizing this properly.

If you want to maximize the transfer of power, then you would match the impedances (Z out to Z in). However, what you are interested in is maximizing the transfer of voltage. In this case having a low Z out to a high Z in, (a deliberate impedance mis-match) is the goal. The source (with a low Z out) is typically not designed to provide much power, specifically not much current (amps). If the impeadances were similar (no deliberate mis-match), then the load would "try to draw" current from the source. This would produce a distorted signal with a poor low end response.

IOW, the issue of whether the B1 provides more current or not probably does not explain why the circuit is useful.
 
What if the source is to quickly charge the input capacitance of the load? Does the provision of current from source preserve transient response?
transients are high frequency signals.
Capacitors are low reactance to high frequency signals.
Having current available to drive a lower impedance load is very beneficial.
This applies particularly to sources driving cables and high capacitance RF filters.

Cordell is one of the very few to discuss voltage clipping and current clipping and why they occur and how to avoid them.
 
I am gathering components to build a B1 and just wanted to know what people are using for 1uf and 10uf caps. Something that sounds good and wouldn't break the bank...:)

For clean, neutral sound I think Erse caps are excellent. $20 min. order but the shipping is cheap. They've gotten a little notice but not much, probably because they're too inexpensive to qualify as boutique.

For warmer tones, Claritycaps are good.
 
Thank you so much. Erse caps look good. Before I place my order do you also have a US link for Claritycaps?

I also forgot to ask, is 250V version sufficient?

EDIT: Nevermind, I found Claritycaps at madisound.

For clean, neutral sound I think Erse caps are excellent. $20 min. order but the shipping is cheap. They've gotten a little notice but not much, probably because they're too inexpensive to qualify as boutique.

For warmer tones, Claritycaps are good.
 
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As Andrew succinctly states; both C100 and C101 are in the signal path. As such, they are equally critical. If C100 adds something ugly or subtracts something beautiful then C101, perhaps the most perfect capacitor known to the universe, can only pass along the maimed signal. The same story can be told for C101 and circuits downstream.

To put a fly in the ointment. Does your gathering of parts include the Pass B1 PCB? If so, you might consider tempering your choice of capacitors with the layout of the PCB. I initially bought whoop-to-do Mundorf caps without regard to the PCB. Reality hit me when I faced boring pads, extending leads, additional mounting hardware, and sacrificing elegance.

You might start by acquiring caps that fit the board without fanfare. Become familiar with the B1 and then bridge in exotic caps to determine their sonic merit. I have not decided but I may sell my Mundorfs to the speaker building crowd before I scar them in any way.