About Switching

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1. Foreword 2.About music 3. About rock 4. About sound 5. About mixing 6. About guitarists 7. About tubes 8. About pedals
9. About digital 10. Ab. compression 11. About saturation 12. About filters 13. About delays 14. About chorus 15. About switching 16. Synthesis

In 2007, every guitar player who reads a little about gear and effects is sincerely convinced that the best switching technique is what we call now true-bypass: a hardware switch that completely disconnects the effect from the audio path.

As a matter of fact, true-bypass does what itís paid for: a bypassed effect doesnít alter the sound at all. In other terms, the true-bypass quality can be appreciated only when you actually do not use the effect!

Letís come back to the origin of effects switching, and see why the true-bypass technique is far from being a perfect solution.

A switching system must provide several functions:

  1. Transmit the signal without loss nor alteration when the effect is off.
  2. Transmit the input signal to the effect and retransmit the processed output signal to the rest of the chain, without loss nor alteration.
  3. Allow switching the effect on and off without signal level difference and without unwanted noise.
  4. If the effect in not at the player's feet, in order to minimize the audio cords length, allow remote switching.

True-bypass is a good answer only to the function 1. If the effect has poor characteristics (e.g. low-cost buffers), it's the worst answer to functions 2 and 3.

As for function 4 (remote switching), true-bypass can be used, provided the designer has included a costly relay system in the device.

All in all - and that's my own experience speaking, rather than a technical approach - true-bypass is truly bad, except in one very specific context:

When you want to merge an excellent tube amp with other devices, especially solid-state gear, the slightest addition to the all-tubes circuits will of course alter the sound.

Alter doesn't mean degrade: the sound is just different. If you really want to keep intact the pure sound of a stand-alone quality tube-amp, and use in the same rig other devices, the only solution is to install remote-controled relay true-bypass systems in your rig.

It's costly, and usually requires custom design if you take into account the fact that each set-up is unique.

Tom Scholz has made the choice of rack-format devices: the only solution to have only short audio cords. He thus needed something reliable to remotely control his gear, and had suppressed the tube amps from his set-up. So what? No true-bypass. Active switching with professional-grade buffers were installed in every Rockman piece of gear, and that was the only way to provide the four functions of a quality switching system.

The Midi Octopus was created to add Midi capabilities to the Rockman rigs: the Octopus controls the footswitches of each module and memorizes the configuration of each preset. For effects without remote footswitch, the Octopus can be completed with Remote Loops: this allows bypassing a stompbox, or basically any non midi device connected to the rig.

Copyright Rockman.fr 2007