Following a discussion for power transformers for the F5X, I think it is a topic which deserves separate attention.
Apart from what VA rating and what core size in relation to to real power consumed, there are many other issues, such as :
1) Core type -- Toroidal, EI, R-Core, C-Core ....
2) Winding type -- multiple thin wires vs single thick wire, bifilar or not, how much insulation between primary and secondary, single-layer secondaries each occupying half of the core perimeter, primary inside or outside, ...
3) Encapsulation 8potting) or not ...
4) Shielding -- electrostatic shield or no shield, magnetic shield will belly belt or case, Mu-metal vs steel vs aluminium, ....
I hope you will share your experiences and have an open discussion. And I particularly hope that Nelson would shed some light on the topic.
So I open the forum to you all.
Patrick
Apart from what VA rating and what core size in relation to to real power consumed, there are many other issues, such as :
1) Core type -- Toroidal, EI, R-Core, C-Core ....
2) Winding type -- multiple thin wires vs single thick wire, bifilar or not, how much insulation between primary and secondary, single-layer secondaries each occupying half of the core perimeter, primary inside or outside, ...
3) Encapsulation 8potting) or not ...
4) Shielding -- electrostatic shield or no shield, magnetic shield will belly belt or case, Mu-metal vs steel vs aluminium, ....
I hope you will share your experiences and have an open discussion. And I particularly hope that Nelson would shed some light on the topic.
So I open the forum to you all.
Patrick
since it's been so quiet, i'll just point out jcarr's experience (and other people's measurements) that toroids have the largest bandwidth, followed by the EI, and then the R core. It goes without saying that a power transformer should be a low bandwidth device (either 50 or 60 Hz only).
However, I've never seen a low voltage/high amperage R core transformer.
However, I've never seen a low voltage/high amperage R core transformer.
Just so we don't get off track.
I think what we really want to know is, what is going to give us the best bang for buck in terms of making a real audible difference.
I am sure it would be possible to spend big dollars on a transformer and not end up with any audible improvement.
It would be nice if Nelson could set us straight here
I think what we really want to know is, what is going to give us the best bang for buck in terms of making a real audible difference.
I am sure it would be possible to spend big dollars on a transformer and not end up with any audible improvement.
It would be nice if Nelson could set us straight here
yes you can, it was pricey, not something that could be recommended to a group at large. worth it for your purposes, in your circumstances and for the quality given maybe, but objectively over the top. remember the recommendations here in this thread are to get to the bottom of quality and value for money for a large group of people. value is different things to different people. for me considering i have never had any problems with using quality toroids, even in dacs and line level where they are probably not the best suited; i dont need another reason to spend more money. i'll try an r'core in the next lineamp or digital crossover i build, but for power amps as long as i'm not having issues i'm not gonna be picky, i obsess about power supply too much as it is
Last edited:
Last edited:
Yeah, mostly agreed. I usually prefer buying cheaper
troids from RS components, or Antek.
But at least as a customized one made in japan, I can't say "insane".
I hope Nikon1975 is pleased with his "special" R-core.
The prices(JPY) of phoenix R-core found on the Link
Patrick had post are all custom-orderd ones.
i opt for custom toroids from sumR, so i'm no stranger to blowing coin on tx and Nikon1975 knows that, he knows i dont mind blowing coin on many things some may see as dubious. i think he knows how to understand me as we have spoken on many occasions. i think this focus on the word insane is funny. i do not mean he is crazy for buying it, i mean its crazy expensive and i believe it is. the possibility of finding an off the shelf 500-600va/15v R-core are 2 chances: slim and ermm 'clean version' not at all. everything in this class will be custom. all the same as i already buy custom, it will depend how crazy os crazy and i have emailed them to see; as a possibility for a chipamp and the ajx perhaps. at 10kg each shipping aint gonna be pretty
Last edited:
I've used "cheap" transformers from RS with 230V primaries and all have buzzed.Used the excellent AST toroids from Avondale Audio in my Aleph 5 build; big improvement in sound quality i.e more detail coming through and better dynamics. But even these had some residual hum if you put your ear against the amp case. I am currently using an audio grade 500Va from toroidy.pl in Poland in an F5 which they wound with a 240V primary; well pleased its as quiet as a mouse.Regarding R cores the only place I've used one is powering a DBC1 and its the only 230V transformer I've used which has been quiet?
I'm interested to see what you get quoted for the big R cores gusp.
I'm interested to see what you get quoted for the big R cores gusp.
Thanks Patrick. I should say that I haven't spent much time looking either.
I should also state that toroids saturate faster than EI or R core, and are therefore more likely to buzz. However, a simple DC blocking scheme can be put in front of a toroid to eliminate this.
Did Nikon ever measure the DCR of his transformer?
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.