09-27-2011, 05:16 PM
I don't think it's that critical, somewhere between 5 and 10 K primary impedence and 4 or 8 ohm secondary should work out fine. Can't do any harm trying out something you may have in your stash provided that it is not shorted or open. Do find out why the old one burnt out before going further. Transformers are pretty sturdy untill crossed.