food for thoughts , and test , one of these days ....
in a meantime , worth to look
http://www.diyaudio.com/forums/solid-state/161663-nem-ai-50-a.html
IMO Mains filters can have a "black background effect" but generally kill dynamics.
I mean using chokes before the 220v windings 🙄
I think we first should clarify what we are talking about: HF drek supression or ripple reduction. In practice, two different jobs.
@ZM: Thx for that. Definitely interesting. Maybe I can get one of those amps for a listening impression.
in a meantime , read this 6moons audio reviews: NEM Ai-50 ;
in fact - look at pics and captures
when you finish with listening test , ya know the drill - to ZM , for proper disposal
Well, pdul, that is the whole issue of mains filtering and i do not want to mess around with that topic at the moment. Post you impressions though.
I heard the NEM and it sounds good. Very alive and engaging.
The circuit is clean and simple. I like that. The output stage is a variety of the diamond buffer.
I heard the NEM and it sounds good. Very alive and engaging.
The circuit is clean and simple. I like that. The output stage is a variety of the diamond buffer.
That RIIA is weird, sounds great though. Needs a good pre-pre or transformer for MC use i think.
I never heard it , but I like what I see ; boyz are totally wakoo 
anyway - I posted that because of their choke input filter ; I'm counting that they're knowing their drek (contrary to ZM , who knows only station
)
anyway - I posted that because of their choke input filter ; I'm counting that they're knowing their drek (contrary to ZM , who knows only station
)
Be sure they do - and they do all of their inductors by themselves. And as they tend to use BIG cores, I am sure those won't have any problems with that DC preload. As I said earlier - totally dfferent from one of those usual common mode filter choke toys.
Sure, when you know your equipment a line filter can be designed in that perfectly fits.
Unfortunately besides making your own sine waves there is no universal line filter.
I know because i designed 90kW DC power supplies for sputtering in the 80th.
Also AC with microwave.
It has exactly to fit or we end up with all kind of resonances. Some filters even put dirt back into the line.
Unfortunately besides making your own sine waves there is no universal line filter.
I know because i designed 90kW DC power supplies for sputtering in the 80th.
Also AC with microwave.
It has exactly to fit or we end up with all kind of resonances. Some filters even put dirt back into the line.
The company i worked for is long extinct but that is what we made :ELAN-Plasma-Drive-Service, Büttelborn - Firmen
Thinking about it i am not so crippled PSU wise as i think. One on my duties was to check for short circuit protection. Have you ever short circuited a 90kW DC supply ?
I did that with a 2m long bakalite stick. I could throw flashes that could enlighten Berlin.
Thinking about it i am not so crippled PSU wise as i think. One on my duties was to check for short circuit protection. Have you ever short circuited a 90kW DC supply ?
I did that with a 2m long bakalite stick. I could throw flashes that could enlighten Berlin.
To tackle ripple we used the resonance principle. That was a bank of big MP caps and huge coils. The cap values where surprising low because of the coils.
One problem was to optimize efficiency, such a PSU can cause a lot of blind current that lowers the energy ticket but also efficiency. The impedance curves we calculated remind me on a complex loudspeaker load. We used similar techniques to flatten the impedance curve. My boss was a big HighFi freak. With tubes of cause and ribbon speakers.
He was a character, also involved in designing atomic reactors when they where new.
He stepped out of that busyness though because he did not trust the safety measures.
One problem was to optimize efficiency, such a PSU can cause a lot of blind current that lowers the energy ticket but also efficiency. The impedance curves we calculated remind me on a complex loudspeaker load. We used similar techniques to flatten the impedance curve. My boss was a big HighFi freak. With tubes of cause and ribbon speakers.
He was a character, also involved in designing atomic reactors when they where new.
He stepped out of that busyness though because he did not trust the safety measures.
food for thoughts , and test , one of these days ....
in a meantime , worth to look
http://www.diyaudio.com/forums/solid-state/161663-nem-ai-50-a.html
Allready love it even without hearing the beast.
Nice explanation about coiled psu in 6moons review also.