VRDN: bipolar regulator PCB for line level ckts: ±11V to ±20V @ 1.5A with "De-Noiser"

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12VRMS * sqrt(2) = 16.97V peak (+16.97 to -16.97)

minus 2 diode forward voltage drops @ 0.7V each --> 15.57V peak

minus peak-to-trough ripple voltage --> about 15V trough voltage

minus LM317 / LM337 input-to-output voltage drop (a/k/a "dropout voltage") --> about 12V DC
 
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Does the VRDN have enough juice to power TWO of the the BA 2018 line stages? I've stuffed (but not tested) two boards for a symmetrical balanced version, hence the question. If need be, I could use two VRDN supplies, powered off a sufficiently beefy transformer, but that'd mean building another one of those, too....
 
@rikiheck

If you search the original WBA18 thread, I had mentioned the current draw of this circuit. And yes, it is exactly as 6L6 states. Needless to say, 1500mA supply capability is more than enough. As a general rule, most of these small line level discrete circuits and also opamp circuits don’t draw much power so the VRDN has likely universal compatibility.

Best,
Anand.
 
I've made a VRDN PSU but it did not make stable output with onsemi 317, 337 and a toroidial transformer 25VA 18-0 dual secondary.
It happened also with connecting the jumpers of bypassing denoiser.

Did I make any mistaks?

 

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I wouldn't worry too much about a $50 multimeter whose displayed output voltage flickers between 18.00V and 17.99V. But if you remain deeply, deeply concerned/worried, you could (A) load the outputs with resistors-to-ground which draw approximately the same current as your final audio gear will draw from VRDN; and also (B) monitor the output waveform with an oscilloscope instead of a multimeter.

For example, if your application calls for VRDN to deliver 25mA to the left channel +18V supply, and another 25mA to the right channel +18V supply, that's a total of 50mA from VRDN's +18 output. Ohm's Law tells us that a 360 ohm resistor has the same current draw {math: 18V = 0.05A * 360 ohms} so if you've got a 330 ohm or 390 ohm or 360 ohm resistor, connect it between VRDN +18V and ground, to achieve a same-current load.
 
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@rikiheck

If you search the original WBA18 thread, I had mentioned the current draw of this circuit. And yes, it is exactly as 6L6 states. Needless to say, 1500mA supply capability is more than enough. As a general rule, most of these small line level discrete circuits and also opamp circuits don’t draw much power so the VRDN has likely universal compatibility.
Unfortunately, it's near-on impossible to find such a thing in a thread with nearly 4000 posts.