OK - I got it mixed up. It was Doc that had the TSL. However, the VS100 will still respond to a brake.
The brake (or soak) should be placed between the power amp and speakers.

For Doc=Your TSL uses 4 - EL34's in the power amp section. I doubt these are original Sovtek's. If these were replaced with Electro Harmonix's, volume is the only way to wake them up.

Hughes & Kettner Red box is around $150.