How good is the Tamura TamRadio iron?

Hi, I tore down the cooked Sony Tamradio output transformer .

The Laminations tested so far are soft shiny and easy to bend by hand as you would expect from Nickel / Permalloy , they are not Silicon steel .

Oddly some appear to have a copper coating very strange , don't think it's the wax , but hey the wax was melted after its mishap maybe when Frank Sinatra and Roy Orbison were laying down some wonderfull analogue recordings .


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Seems the last chapter in this Sony 5K Tamradio cooked output transformer tear down .
3P/2S sections layering .
The 8 ohm secondaries are not multifilar wound , which would account for the HF roll off at 18kHz according to the Sony manual.
IMHO what are most likely Permalloy core's account for the lifelike sound qualities of these little units rather that anything particularly special about the winding technique of Tamradio / Tamura here .
As I have a few of these , am looking to rewind a pair with 4P/5S sections with no 600 ohm tap , mutlifilar this time .
Will also look to blend the original cores 50/50 with M6 Silicon steel to get better bass response .
If you were looking for a 5K full range transformer Lundahl do an excellent one


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This is going to be my last attempt at trying to find a use for a pair of there output transformers...

Not sure I have this correct; if I were to use the 8r taps on my 16r speakers the primary’s would work out to be 2.5k rather than 5k? I think doing this would be problematic in other ways, the 5 W they are rated for would be reduced I think?
The primary load your tube “sees” will be 10k. If your speakers are nominally 2x your taps, the primary impedance will also be nominally doubled.