For the use of loads greater than 0.8A, I would always use an L-adapter. L-adapter is good enough in terms of noise and stability under "high" loads. very good or excellent I would say.
Ubib is more recommended for loads of audio applications such as preamplifiers and dacs with "small" consumption less than 0.8A. especially dacs that can produce noise on the power bus directly.
Ubib is more recommended for loads of audio applications such as preamplifiers and dacs with "small" consumption less than 0.8A. especially dacs that can produce noise on the power bus directly.
I believe that noise could be a result of transformer stray fields affecting power ground wires. UBiB or Jung-Didden voltage regulators are among the very best you can find anywhere, both by measurements or sonically and not prone to be directly affected by stray fields.
Here is a noise measurement, first directly at UBiB rail in my preamplifier. It is at -120 to – 140 dBV levels or at 100 to 10 nV/rtHz noise density, including environment noise pickup, which is inevitable at that low levels. Noise floor is not flat because laptop power supply was connected during that specific measurement.
Next is noise measurement at Salas’ DCG3 preamplifier output (powered by UBiB regulators), with signal at only 1 mV level. Measurement is deliberately taken without any averaging. Mains hum and 100 Hz noise are again below -130 dBV levels. Hard to measure, impossible to hear under any conditions imaginable. You have right voltage regulators. Take care about wiring and proper transformers arrangement and you could have noise free audio circuits.
Here is a noise measurement, first directly at UBiB rail in my preamplifier. It is at -120 to – 140 dBV levels or at 100 to 10 nV/rtHz noise density, including environment noise pickup, which is inevitable at that low levels. Noise floor is not flat because laptop power supply was connected during that specific measurement.
Next is noise measurement at Salas’ DCG3 preamplifier output (powered by UBiB regulators), with signal at only 1 mV level. Measurement is deliberately taken without any averaging. Mains hum and 100 Hz noise are again below -130 dBV levels. Hard to measure, impossible to hear under any conditions imaginable. You have right voltage regulators. Take care about wiring and proper transformers arrangement and you could have noise free audio circuits.
What do you mean by'proper transformers arrangement'
Thanks.
I just finished my two UBIB,plug now,They feed a clock board,It works really well,Very detailed medium.
I would post photos tomorrow.
Thanks Salas.
Just usual good practices. To use good quality transformer type, to put transformer further from the sensitive circuits, twist together transformer wires, check transformer orientation (if it is type with considerable stray fields and no shields) and so on. On path to low noise every detail helps.
Builds with long wires all around are expected to have some noise.
I have tried few more times with cheap rcore transformer but nothing changed.
So I gave up and got 50w 115v/25v toroidal transformer.
There was not enough good bass sound so I tried sic-sbd reflector in each secondary then
bass sound fixed.
Also changed to nichicon kz cap for my liking sound.
Now it is sounding amazing details and texture.
So I gave up and got 50w 115v/25v toroidal transformer.
There was not enough good bass sound so I tried sic-sbd reflector in each secondary then
bass sound fixed.
Also changed to nichicon kz cap for my liking sound.
Now it is sounding amazing details and texture.
What's "reflector"? Marked Rf at Salas schematic? Or you are speaking of the Quasimodo snubber Cx, Cs & Rs at Salas schematic?
If you used snubber the values must be set by oscilloscope.
No matter when the snubber is fitted, only important thing is always between the power transformer & the diode bridge!
I'm Catalan so understand your problems speaking foreign language.
If you used snubber the values must be set by oscilloscope.
No matter when the snubber is fitted, only important thing is always between the power transformer & the diode bridge!
I'm Catalan so understand your problems speaking foreign language.
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And you said using external PSU (diode bridge + mains capacitor) fixed the noise? Did you used the same bridge diodes & same capacitors? Or do you use a separate box for the PSU, if not no makes sense?
No,cheap rcore transformer making noise then changed to better quality toroidal transformer fixed. I still not understanding why but I don't have skill to find out what is exactly making noise.
I built external PSU for ACP+ instead of SMPS.
Also I can use my future build(B1 pre with korg nutube).Just for convenience.
I built external PSU for ACP+ instead of SMPS.
Also I can use my future build(B1 pre with korg nutube).Just for convenience.
I used this O Core with the UBIB for feed a oscillator board,The sound is incredible, full of life,most impressive is the bass frequence.
Photos when the case is finished.
Photos when the case is finished.