Which regulator for phono preamp?

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I'm building a Pete Millett's LR Phono stage and need a +/- 15V source.

I've got an assembled AMB sigma22 and transformer from a different project but its fairly big and would increase costs since I'd likely use dual chassis to put the transformer and PSU separately from the Phono board.

I've recently discovered Jan's SuperRegulator, and SilentSwitcher, both could work fairly well.
I like that the SilentSwitcher is small and can fit in the same chassis as the LRP.
The SuperReg also looks like a relevant option that could also fit in same chassis with a "wall-wart" supplying the power.

Which would you choose and why?
 
Hi, Try this one, I used it for my A/K AD797 MC phono amp. It replaced the Silent Switcher, which I found to noisy.
MJE15034 TL072 Regulator Power Supply Board For Pre AMP DAC Based on STUDER900 | eBay Cheers
IMO, using a TL072 in a voltage regulator is a POOR idea----they're already at 18nV√Hz noise voltage to start with---WAY too much. You'd be MUCH better off with one of the circuits in the DeNoiser thread like the one in post #518 (D-Noizator: a magic active noise canceller to retrofit & upgrade any 317-based V.Reg.). It works, it's quiet and it's cheap. It'll blow the doors off that eBay TL072 regulator!
 
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I forgot to save the link but there was a blind test done of regulators a while back which came up with some interesting results. I'm on a mission to have only my power amps mains powered so for me the silent switcher was a no brainer.


EDIT: Article is here Linear Audio | your tech audio resource but does appear as a free download if you google it. Jan is that correct? This was a test for line stage operation but the results are applicable to phono as well.
 
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I'm building a Pete Millett's LR Phono stage and need a +/- 15V source.

I like that the SilentSwitcher is small and can fit in the same chassis as the LRP.
The SuperReg also looks like a relevant option that could also fit in same chassis with a "wall-wart" supplying the power.
Which would you choose and why?
I found using a DC supply wall transformer solved my hum problems without a second steel enclosure inside my preamp chassis (the way dynaco PAS2 & peavey mma-875t do it). Besides steel jacketed copper banded EI transformers are hard to buy without scrapping out one of the above.
I don't need +-15 since my loudest source is 7 vac radio earphone jack. I use +- 8 v supply from a pair of 1n5344 zeners stacked. Wall transformer is +18v.
People obsess about microvolts of PS noise yet let CB radio, AM radio, lightning on the power line, right into their preamps. I stop all that stuff with a 22 turn choke right by the power inlet- salvaged from a PCAT ATX supply. Followed by a salvage MOS supressor across +-. The double pi hum filter also has .1 uf disk caps. Of course, a grounded steel box is necessary to keep the EMF out, and 33 pf disk caps across all inputs. Turntable green wire goes to the steel box, also the safety ground from the power strip.
 
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I forgot to save the link but there was a blind test done of regulators a while back which came up with some interesting results. I'm on a mission to have only my power amps mains powered so for me the silent switcher was a no brainer.


EDIT: Article is here Linear Audio | your tech audio resource but does appear as a free download if you google it. Jan is that correct? This was a test for line stage operation but the results are applicable to phono as well.

Yes, that is correct. For now ;-)

https://linearaudio.nl/sites/linearaudio.net/files/v4 jdw.pdf

There are also color versions of several graphs available here: Downloads | Linear Audio but you need to scroll down a ways.

Jan
 
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I am using the SilentSwitcher to power a JFET amplifier for very noise (600pV/RtHz) measurement. If low noise is your aim that's the one to go with.

BTW, looking at Pete Millett's design, you could place the 75uS pole ahead of the first AD797 by lowering the value of R1 to take into account the inductance of the MM cartridge. The HF response of this design otherwise is not the greatest.
 

I remember this one. Despite some potential controversy in its findings it is rather interesting.

Perhaps my viewpoint has changed since the last time i read it as i now find an obvious omission in the subjective test: listening to the DUT with no regulation at all. This obviously places greater demands towards the raw DC quality such as low ripple, preferably choke input filter, low rectification noise.
 
what about the 7dB noise penalty that gives you? Or do you mean Cordell style 'damped' loading with an 8kHz roll off?

I was at the other location without my usual test setup. I ran this test several times with LME49710 and 47k and 11k load resistors and an Audio Technika VM540ML cartridge. I don't see the noise penalty. 7dB should be 2.2x noisier.
 

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