If I was to use a triode-wired 6J9P (Russian pentode which makes a triode similar to 5842), or even a 6J52P-triode (I have a few), I'd want a 10k:50 OPT for Fostex TP50R headphones (50 ohm impedance)? Edcor makes one of those for like $10 each (https://www.edcorusa.com/xse10-50-8k), but it's only rated for -1dBu at 70Hz at rated power of 10W.
I don't see a spec for primary inductance. Does a transformer rated for 10W have a wider frequency response with <1W output? Or is the primary inductance always going to be the limiting factor?
The reason I ask is that old Tango specsheets show their OPTs yielding wider bandwidth at 1W out than at say 10W or more. But they don't show bandwidth at 1/10 of a watt.
I don't see a spec for primary inductance. Does a transformer rated for 10W have a wider frequency response with <1W output? Or is the primary inductance always going to be the limiting factor?
The reason I ask is that old Tango specsheets show their OPTs yielding wider bandwidth at 1W out than at say 10W or more. But they don't show bandwidth at 1/10 of a watt.