BPPBP - Bruno Putzey's Purist Balanced Preamp (well a balanced volume control really)

...The amp has an XLR input
and expect two signal out of phase.
it hasn't a balanced nor a differential input.

:D

Differential signal drive and balanced signal interconnection are not necessarily the same thing. Are you certain that your amp features two independent signal paths (one for each half of the bridge) fully from input to output? An XLR input connector does not necessarily mean that true differential (complementary phased) signal drive must be furnished. It simply means that a balanced signal interface for the purpose of common-mode noise rejection is supported.
 
Do you have one more bare board, please?

I still have 4 bare BPBP boards, they are 3 euro each plus postage (using standard letter post only). The boards are white, not green, in colour. PM me if interested.

Hi, any bare board left for me, please? If yes, please send me a PM with your PayPal address and the price including shipping to Romania and we'll talk about details.
Thanks for the quick answer!
 
Hello,

This is my first post here and I will start by thanking everyone who contributes to the forums on this website.

Now, has anyone used an Ncore Vaux output to power this preamp? I am looking at the nc252mp which gives +/-20v (+/-1v) and supplies up to 1A on each rail. Does this make sense?

I tried searching the thread but found nothing.
 
AX tech editor
Joined 2002
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Probably need to check the max dissipation on the Hypex data sheet. If you have 22V in, 12 volts out, and say 100mA current draw, your dissipation V*I for those regs is (22-12)*0.1=1W.

If that is too high, you can for instance put a 4.7V zener in series with the reg input to absorb some voltage, and with that part of the dissipation (which now is in the zener of course).

Jan
 
AX tech editor
Joined 2002
Paid Member
Hi Jan,
How does your SilentSwitchers compare to Jung/Didden Regulator in terms of noise and output impedance?

Could I use 6,6V battery with it to create +- 12V for this preamp?

Thanks in advance.

Yes 6.6 input works fine. Max current at +/-15 is 150mA, at +/-12 about 180. Should be enough for Bruno's preamp.

Quality is very close to superreg, probably bit lower noise, bit higher Zout. But all the numbers are very low anyway.

Jan
 
@jan.didden

Thank you for your answer. I received the BPPBP board last week, and now need to decide which power supply and potentionmeter to use for this project.

Today, I find a schematic for one PSU, which was called GRLV and developed by Kevin Gilmore based on Walt Jung's design.
I would be very grateful if someone with deep knowledge like you could comment some opinion about it

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