[sdiy] inductor based distortion

[René Schmitz]

Hi Jürgen,

Well I think two factors play a role here. First of all most OTs for 
guitar amps are "underdesigned". (At least from an audio point of view.) 
Sort of like less iron -> more sound. (and less weight, cost...)

When a tube is overdriven you change its effective bias point.
Normally you assume symmetric drive arround the quiescent point.
With substantial overdrive the DC point shifts towards higher
current and can thereby lead to overheating in the windings.
(The smaller core means a high current density already, so a little more 
can cause "problems".)

Then there is that other popular method of killing a transformer. No 
load connected. Then the insulation breaks down by the high voltages 
from the inductive kickback.

Cheers,
  René

-- 
uzs159 at uni-bonn.de
http://www.uni-bonn.de/~uzs159