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Recommended output valves for this transformer

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I noticed that RS in the UK are selling a multi-tapped 3.5W output transformer (210-6475) at a very attractive price. Although intended as a universal SET replacement, I noticed that the primary taps might allow it to be used as a push-pull transformer. It's impedance would be rather low but I wonder if something like a ECC99 or 12BH7 could be used to make a class A Triode P-P headphone amplifier?
Best Regards
Les
P.S. For some reason the Forum will not take an attachment of the transformer details in jpeg or pdf formats. Basically the primary turns are 2000:1000:1000 with the secondary turns 64:31:41.
The transformer matches 3 to 15 Ohms speakers to 4k to 15k Ohms depending on taps used. Info is available on the RS website if you search for the part number 210-6475.
I was hoping to use the 3/4 ohm taps with the 15 Ohm tap providing FB if it was deemed necessary.
Cheers
 
I remember that tranny. I thought it was a 100hz - 10,000hz tranny. RS never carried super high quality stuff, just adequate replacements. So I checked around and found the data sheet. Sure enough, primary inductance at 100hz is 12.5 Henries. This is really ideal for speach circuts.

heres the data sheet.
 

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