Transformer wah blues

[gez]

Has anyone EVER managed to get a decent sound from a output transformer used as an inductor in a wah pedal?

Although I have a Cry Baby, I thought I’d play around with some ‘Eagle International LT 700’ transformers on the breadboard.  I measured an inductance of 400mH across the outer lugs of the primary, wired up a typical circuit and, although it works, there’s hardly any wah on the bass strings.

After a couple of days of tweaking and trying out just about everything, I still can’t get much of a wah sound on the lower two strings.  It seems that the resonant peak just isn’t strong enough.  I removed the 33k ‘Q resistor’ and made the feedback cap bigger, which did give a nice (albeit subdued) vocal wah effect in the mid range, but precious little down below.  I even tried wiring up another transformer in series to get 500mH, 600mH and 800mH, which results in a slightly deeper wah effect as the inductance increases, but the lower strings still sound weak.

I even tried bootstrapping the inductor, which (and I don’t know why I expected anything different, but that’s desperation for you!) made things louder, but no better.

So, are there are any tricks that might help kick-start one of these little suckers into life, or has anyone successfully designed something and would be willing to share a schematic?  No suggestions along the lines of  â€˜use a such and such inductor from so and so’ please, that isn’t my question (and I already have a decent wah pedal).