Possibly noteworthy: Sutherland Engineering's "MCX" moving coil preamplifier uses a switch mode power supply, visible on the left of the photo.
Perhaps if an SMPS can work well in a moving coil preamplifier, with its incredibly low noise floor, an SMPS can work well in other types of audio gear as well.
The MCX also takes "Dual Mono Construction" to the extreme: two chassis, two power supplies, and two AC mains power cords (!)
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Perhaps if an SMPS can work well in a moving coil preamplifier, with its incredibly low noise floor, an SMPS can work well in other types of audio gear as well.
The MCX also takes "Dual Mono Construction" to the extreme: two chassis, two power supplies, and two AC mains power cords (!)
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We had Jan's silent switcher doing phono duty tonight (no special considerations save a little local bypass) no problems at all.
It uses a step up transformer. That is a crutch to not have to deal with PSU noise, amongst other things. I'd like to see the same SMPS used to power some transistors directly tied to the MC cart. Some noise gremlins would likely see the light of day.Possibly noteworthy: Sutherland Engineering's "MCX" moving coil preamplifier uses a switch mode power supply, visible on the left of the photo.
Perhaps if an SMPS can work well in a moving coil preamplifier, with its incredibly low noise floor, an SMPS can work well in other types of audio gear as well.
The MCX also takes "Dual Mono Construction" to the extreme: two chassis, two power supplies, and two AC mains power cords (!)
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How much active gain?We had Jan's silent switcher doing phono duty tonight (no special considerations save a little local bypass) no problems at all.
It uses a step up transformer. That is a crutch to not have to deal with PSU noise, amongst other things. I'd like to see the same SMPS used to power some transistors directly tied to the MC cart. Some noise gremlins would likely see the light of day.
SMPS can be filtered very effectively. Murata and other companies have entire product lines with ferrites, common-mode chokes, 3 terminal capacitors, etc. for this purpose.
I'm converting both my MM and MC phono to silentswitcher. Alright there is a linear regulator after the switcher, but the core benefit for me is the removal of any mains connection except for charging. So a whole set of issues is wiped out and the cabling gets neater. Serious WNTL.
How much active gain?
IIRC it was ~66dB and a little low for the cart. I would have liked to have had the chance to optimize everything but we made do with what was around. I frankly don't play with $5000 carts in my personal system.
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The nice thing with the linear reg following the switcher is that you can tailor the drop out for lowest dissipation. In the Silentswitcher the drop out overhead is 0.7V approx. At 150mA load thats just 100mW.
Couple that with 60+dB PSRR at 1MHz (!) and the only other thing to take care of is the PCB. Unbeatable.
Jan
Couple that with 60+dB PSRR at 1MHz (!) and the only other thing to take care of is the PCB. Unbeatable.
Jan
I can tell it's crap already if it is using Samxon and Jamicon capacitors as shown in the picture.
Yes - lower Z caps at Fo=100KHz would be better... however there is a noise spec. I'll try a spectrum analyzer test on it and see what is there.
THx-RNMarsh
THx-RNMarsh
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It's not that they are poor on paper, but Samxon is known to have been a brand that had huge failure rates on cheap PC motherboards and some TVs a number of years back. They are a low end supplier. Seeing them doesn't give me a good feeling about the rest of the components in the design.
That is good point... and, i dont think any smps will be as reliable as a transformer etal
-RNM
-RNM
There is a schematic for a similar power supply they make: http://connexelectronic.com/wp-content/uploads/2017/09/SMPS500R.pdf
For Mr. Agitator 🙂
Technical manual
https://www.adminstrumentengineering.com.au/files/mean-well-user-technical-manual.pdf
Test datasheet
https://www.jameco.com/Jameco/Products/ProdDS/2152690.pdf
George
Technical manual
https://www.adminstrumentengineering.com.au/files/mean-well-user-technical-manual.pdf
Test datasheet
https://www.jameco.com/Jameco/Products/ProdDS/2152690.pdf
George
THx-- high quality -- too low voltage and current for PA.
🙂
Mr Agitator.... good if it gets people thinking again.
🙂
🙂
Mr Agitator.... good if it gets people thinking again.
🙂
distortion graphs for M2 compression driver (D2430K) on audioheritage site
D2430K compression driver information? - Page 5
cheers
Alan
With stock M2 amp/DSP/xover only --- no EQ for room acoustics; minimal room affect due to narrower radiation and CD. Measured at 12 feet from center line between spkrs (listening position)

THx-RNMarsh
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There is a schematic for a similar power supply they make: http://connexelectronic.com/wp-content/uploads/2017/09/SMPS500R.pdf
With this type of equipment, the schematic is pretty useless for judging the performance. Surely it will provide the designed output voltage when switched on ;-)
It's the stuff you don't see that can make or break it, performance-wise.
Jan
The rash of failures a good few years ago was caused by a supplier letting some dud documents get stolen, that had an incorrect electrolyte specified, that faulty recipy was then shared around by several companies, and a short while after they were made they all started failing...It's not that they are poor on paper, but Samxon is known to have been a brand that had huge failure rates on cheap PC motherboards and some TVs a number of years back. They are a low end supplier. Seeing them doesn't give me a good feeling about the rest of the components in the design.
The rash of failures a good few years ago was caused by a supplier letting some dud documents get stolen, that had an incorrect electrolyte specified, that faulty recipy was then shared around by several companies, and a short while after they were made they all started failing...
Audio Research lost all their amps with failed ps electro-capacitors, also.
here is what you can do with EQ for headphones.... they needed EQ'ing where M2 doesnt.
software indicates speakers being tested but isnt true.. headphones.

THx-RNMarsh
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