Has anyone tried an R-Core output transformer on their SET amp?
Have been looking at these and would be interested in hearing anyone's opinion about r-core opts.
Softone RW-40-5 Single-Ended Audio Output Transformer
Thanks
Have been looking at these and would be interested in hearing anyone's opinion about r-core opts.
Softone RW-40-5 Single-Ended Audio Output Transformer
Thanks
The problem as same as in case of toroid SE OPT: constructing air gap within the core.
It's no coincidence that none of the manufacturers tried it, except Softone.
It's no coincidence that none of the manufacturers tried it, except Softone.
I have had a pair of the RW-20's for over 10 years and are presently in a Tubelab SE amplifier with 300B's. I am happy with them. They are also very versatile.
The ones you linked to are even more versatile with 2 separate Cathode windings and I too have been looking at them (RW-40's) for another project.
The ones you linked to are even more versatile with 2 separate Cathode windings and I too have been looking at them (RW-40's) for another project.
I bought a pair of RW-20s from a forum member and haven't actually used them yet so can't comment on their performance. But the bracket that holds the trans vertically inside the can was poorly made. It could have used a bit more weld.
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I just realized that according to Softone the SE trans can be used for push-pull too. My next project will be a 6L6 P-P amp so they just might get some action there. Anyone have any experience using them P-P?
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Softone are good transformers. The PP ones are fine, SE and IT transformers are lacking a bit of primary inductance but for the rest they are good and they are best used with low plate resistance tubes.
The IT transformer is one of the very few affordable SE😛P transformers with excellent phase splitting balance and it's also very versatile.
That specific SE model is fine with 300B or 2A3 working at 60 mA.
Good question. No idea, just suspicion they are manufactured already with a gap and this is not cut later. Also winding coils around 1 piece core is not that straightforward.
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It is pretty straightforward. The two bobbins are freely rotating around the core, and each has a little gear to engage with winding rotator. R-core technology allows simple winding technique for a gapless core, without complications of winding toroids.
Gapless or gapped does not make much difference. The gapped transformers I think they are still 1 piece.
Hello all.
I`m waiting my softone RW-20 transformers, can someone tell how much is DC resistance? Thanks.
I`m waiting my softone RW-20 transformers, can someone tell how much is DC resistance? Thanks.
I have used the Softone RX-30-8 and RW-20 output transformers, and the RC-20 interstage. I agree with 45, these are good transformers that perform just as Softone advertise.