Nat, the Khozmo is out, replaced with a much less fussy TKD TC601. Job done, now, no more fiddling with this.
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.
Yes, balanced is not necessarily differential. This preamp works differential, so you could connect a single ended signal between the two inputs of the XLR.
Look at the schematic and it will be clear.
Jan
Look at the schematic and it will be clear.
Jan
Could I replace the R2/30, R3/31, R13/40, R14/41 resistors from 1k to 1k5 Ohm without changing the quality of this circuit? I don't think it change anything too much, but I can be wrong here
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You can do that, but you'd need to increase R8/35 and R17/44 to 15k to keep things exactly as they were.
Do you have one more bare board, please?
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!
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.
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.
I think the power supply requirement is in the article, and iirc +/-22V at 1A is more than enough. But check to be sure; +/-22V may actually be a bit high for dissipation in the local regulators, depending on which ones you use.
Jan
Jan
Thank you Jan.
I did read the article but only found reference to the Hypex regulators. I plan to use them in my build.
I did read the article but only found reference to the Hypex regulators. I plan to use them in my build.
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
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
Or use one of my SilentSwitchers, mains free, can run from a USB charger/port or a Powerbank.
Overall cheaper even I think compared to 2 Hypex regs and the primary supply. 😎
Jan
Overall cheaper even I think compared to 2 Hypex regs and the primary supply. 😎
Jan
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.
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.
It was a noticeable improvement feeding +/- 15dc straight to the caps after the rectifier vs ac.
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
I could imagine that as it could reduce the pulse current of diode, when switching, to ground of signal path.
What regulator do you use in your BPPBP?
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@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
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