I think class Y2 ceramic could be a good choice. As best I understand a Y2 is 2 x class X2 in series allowed for use between live ( hot/line ) to ground having UL and CB status ( CB is a universal rating which converts to JIS etc ). They are very high grade and cheap. 470 pF to 10 nF are typical values. Silver ceramic is often stated. I suspect they could have good audio qualities as do class X2. What makes a capacitor safer can make it sound better.
All the same, soft recovery diodes do a really good job without additions.
I am sure someone has said an AM radio will show diode noise. That could be tested with a simple load so as not to introduce SMPS noise into the story. It could be said why bother with the diodes when other factors are dominant. Simple, we make good whatever we can.
I do remember years ago Rotel sent me 4 x 10 nF to fit to a RA820 rectifier to help the Rotel AM tuner work ( AM/FM manual tune type RT830?). It was totally sucessful. Before it was like the stations were far away under hiss. It's hard to say if there was undetected noise the amplifier would weave into it's sound. Many say 1 x 10 nF to the AC input to the rectifier would have been better.
All the same, soft recovery diodes do a really good job without additions.
I am sure someone has said an AM radio will show diode noise. That could be tested with a simple load so as not to introduce SMPS noise into the story. It could be said why bother with the diodes when other factors are dominant. Simple, we make good whatever we can.
I do remember years ago Rotel sent me 4 x 10 nF to fit to a RA820 rectifier to help the Rotel AM tuner work ( AM/FM manual tune type RT830?). It was totally sucessful. Before it was like the stations were far away under hiss. It's hard to say if there was undetected noise the amplifier would weave into it's sound. Many say 1 x 10 nF to the AC input to the rectifier would have been better.
We are testing using spectrum analyzer..however the precision is not quite the same.
Ripple and noise in included in the above graphic ...you can see the ripple at 50Hz (less than 100nv).
As far as switching frequency that happens at 40Khz-80Khz (depending on load) and before the Active Noise filter we have at it 900uV..
Active noise filter has a realistic psrr of 40db (40- 100Khz) ...
Ripple and noise in included in the above graphic ...you can see the ripple at 50Hz (less than 100nv).
As far as switching frequency that happens at 40Khz-80Khz (depending on load) and before the Active Noise filter we have at it 900uV..
Active noise filter has a realistic psrr of 40db (40- 100Khz) ...
We will advise once we are closer to finalizing . but from a technical point of view we solved all problems
Still testing has to be done with 110V , more test data with 1Mhz and 20Mhz , then FCC/UL testing.
Looking forward to getting one from the first production run to test out on my system. I'm currently using an iFi ipower with a shunt to ground(on the same duplex outlet) which performs better than a standard smps. I have always been wary about the cheap linear psu's on eBay/aliexpress and there is no reason that a SMPS cannot provide clean power if properly engineered.
Me too, I don't like it, it stinks. Mine spreads an "electronic" smell all over the room that now we are entering the summer is getting worse. It runs quite warm too, much more than a 10 Euros generic one.
I don't know if the smell is general or It's just my sample, but I'm begining to hate this piece of junk.
I'll wait for this new smps or buy/make a linear power supply for the resident USBridge, altough I would prefer a smps as I have the transport allways on.
Is there an aprox. date of launching?
Best Regards.
Audio Myth - "Switching Power Supplies are Noisy" - Benchmark Media Systems, Inc.
Cost is also a factor, a good linear psu such as Sbooster is ~ 300 euro!
Cost is also a factor, a good linear psu such as Sbooster is ~ 300 euro!
They would say so (Benchmark), don't they?... everything goes for propping up own power amp! If there a 'myth', where's the technical back-up (diagrams and all)? Quite a feable 'myth' buster...
I wonder why most of the audio companies prefer the designing and use of linear power supplies against the 'well sorted' SMPS... hmm...
SMPS like Diesel engines is extra design work to do. Both can be very good. The massive advantage SMPS seems to give is over current protection and regulated voltage free of charge. These things are easilly possible with linear designs. For a design that can be sold around the world the linear supply might be about 50% efficient which is a big problem. In the ideal world a PSU should work between 200 to 253V or 100 to 130 V USA. Trust me these figures are correct as the people most often wanting low noise live in bad areas.
I recently built the old PW Texan amplifier circuit using a Meanwell 48V SMPS. It was so good to be able to nail the voltage. As it wasn't a hi fi application I was very happy with the performance. It's problems were no worse than a Hypex UCD 180 I measured due to SMPS noise. I had no interest to hear it. However it might please me more than a class D for a sub woofer. BTW, The Texan is far better than I thought. I used TIP35/36 and reduced the output gain to 3. A class D amp let go during a testing session caused my interest. The Texan should be future proof, it seems the Meanwell prevented the Texan getting killed along with tough outputs. There was no mystery as to why it blew up. Strangely I blew the class D on the SMPS. It must be the over current protection was too slow for the class D. The load is high inductance with very low DCR.
I recently built the old PW Texan amplifier circuit using a Meanwell 48V SMPS. It was so good to be able to nail the voltage. As it wasn't a hi fi application I was very happy with the performance. It's problems were no worse than a Hypex UCD 180 I measured due to SMPS noise. I had no interest to hear it. However it might please me more than a class D for a sub woofer. BTW, The Texan is far better than I thought. I used TIP35/36 and reduced the output gain to 3. A class D amp let go during a testing session caused my interest. The Texan should be future proof, it seems the Meanwell prevented the Texan getting killed along with tough outputs. There was no mystery as to why it blew up. Strangely I blew the class D on the SMPS. It must be the over current protection was too slow for the class D. The load is high inductance with very low DCR.
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