Our JB Gold amp mod

Why your preamp will love our JB Gold modification
Our JB Gold gain stage supercharges your tubed preamp.  Bob Backert, the force behind RHB, designed it to be the only circuit in the world with Active Management. This technology optimizes the preamp for each specific tube you insert (see "Tube Rolling" over to the right).  It also continually adjusts to match the needs of your tubes as they age.  Most importantly, it stabilizes bias in real time by continually negating the "bias tugging" effects caused by playing music....  More

Power supply mod

Our GreenForce power supply will rock your world
Our patented GreenForce™ power supply mod (learn more here) is so innovative that some have called it radical. One reason:  GreenForce eliminates the nasty electrolytic capacitors in your power supply, replacing them with the highest quality capacitors in the world, such as V-Caps. In fact, GreenForce is the only power supply in the world that can do this.  Now, you get real dynamics, and unbelievable rhythm.   More

Tube rolling

Our preamplifier modification lets you really hear your tubes
Our unique circuit lets you hear the best out of each tube you insert.  No other preamp gives you this.  Here's why.  Every preamplifier wants certain operating parameters (voltage, current, etc.) to sound its best. Changing tubes will always slightly alter these parameters. A preamp that does not have its exact ideal operating parameters will not sound its best, no matter how great the tube might be.  Our circuit automatically corrects this, so that your preamp will always have its ideal operating parameters, no matter which tube you insert.  More