In the past I had a very positive experience substituting a 6SN7 for the 12AU7 in a Bottlehead Crack headphone amp. You need an adaptor. I used the one available from Garage. I suspect you could try the same substitution in the TU-8600. Any thoughts?
6SN7 draws 600 ma of filament current. A 12AU7 draws 300 ma filament current in parallel mode .
Simply replacing 12AU7s by 6SN7s would double the filament current drawn . That could easily burn out the power transformer if its rating is marginal.
I do not recommend ..
There are a lot of Good 12AU7 in the market..
Simply replacing 12AU7s by 6SN7s would double the filament current drawn . That could easily burn out the power transformer if its rating is marginal.
I do not recommend ..
There are a lot of Good 12AU7 in the market..