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Electronic Transformer heating for the gm70 test

Posted by used-hifi on January 28, 2017 at 08:21:43:

Lots of discussions on these type of electronic transformers as a good alternative to the much more expensive to implement regulators
upon first listening they made the music sound muffled, then in about 20 mins it all came together somehow, now from these initial experiments I can clearly see why anyone would go this way, these things are small! very easy to implement (cheap) and make the music sound good

I needed about 20v for the gm70 so i added enough capacitance "1000uf" to the bridge rectifier to get about 20v 19.6 actually on the output, I did order more proper caps 1200uf 200v in a single cap these here that i have are 4700uf 35v wired in series no need to wind more turns on the transfomer.
some things I do not like I can clearly hear this unit oscillate at 37kc! so i will need to put it back into its enclosure, Yes I have bat hearing
the other thing I dont like is there is no ramping up its voltage it all comes on the instant you plug it in, so no slow or soft start maybe add a mov?
I am reluctant to say that these are as good as rod's regulators but they are prob good enough more testing on proper speakers will tell more of the story, my large fulton speakers will play way out hi 80kc!, so if there is something I am missing with my little fulton speakers these will tell the story.
I am familiar with real musical instruments
so here is What I listen for:

Proper form and function the sound from various instruments, bass drum, brass instruments all these have a certain sounds and brass has a certain peculiar attack along with is beautiful brass sheen when played in the upper registers, Piano need to sound right its a percussive instrument

Lawrence
p.s. a few Thanks go out to defbykhorns and RayP Thanks for all your help.