As more guitarists turn to recording in the comparative tranquillity of their own homes, devices such as speaker simulators become very attractive; in theory, they enable a more or less live guitar sound to be recorded without the need for loud amplifiers or microphones. The basic idea is that a small box of electronics simulates the tonal characteristics of a typical guitar speaker cab; simply plug the output from a guitar preamp or effects pedal straight into the simulator, plug the simulator into the mixer, and there you have it — instant rock guitar.

More costly speaker simulators generally include a dummy load, which replaces the speaker in a conventional guitar setup, the advantage being that all the preamp and power amp overdrive characteristics are faithfully transferred to the simulator without the need to make any noise at all.

Dummy loads are necessary, especially in the case of valve amplifiers, where the output stage can be seriously damaged if run for any period of time with no speaker connected.

The less costly units, of which this is one, contain no dummy load; you can either plug a preamp or pedal directly into the Red Box, or you can insert it between the amplifier and loudspeaker. In this latter configuration, you get the sound onto tape without the need for a mic, but as the speaker is still connected, it's hardly silent. Still, you could always bury your speaker under a pile of cushions!

The Red Box is — well — a red box about the size of an effects pedal, running from a standard 9V battery or an external 9V power supply; inserting an input jack turns on the battery. The output of the unit is a balanced XLR connector which purports to be line level, but in practice, it works fine into the balanced mic input of a typical mixer. The Line input is an unbalanced jack for direct connection to guitar preamps or pedals. Two further jacks are fitted, enabling the unit to be placed between amplifier and speaker. That's it, just plug in and go.

The results achieved using the Line input with my little Fender Champ were exceptionally good; the resulting sound has plenty of definition and bite, but all the buzz associated with DI'd, overdriven guitars is filtered out. The result is very much what you'd expect when miking conventionally. Of course, you need an amp that relies on its circuitry to create the overdrive effect — if your shredded speaker is what gives you your sound, then this box won't help! In this light, valve amps seem to work best. With the Champ, I used my own dummy load, (a high wattage, 8 ohm resistor), to keep the noise down, but with a master volume type of amp, you should be able to use the preamp output and turn the master level down to silence the speaker.

Used with a couple more preamps and pedals, the results were still creditably usable, and the speaker input works equally well, with one caveat: you have to make sure the speaker polarity is correct on your amp. The speaker output on my Champ is hand wired and the polarity set to go with my Palmer speaker simulator. This didn't agree with the Red Box, which produced all kinds of buzzing and squeaking noises. Swapping the speaker leads cured this and it sounded great.

Both clean and overdriven guitar sounds translate to tape pretty faithfully via the Red Box, though you must remember that it does nothing on its own — you have to use it in conjunction with a suitable guitar amp, guitar preamp/effects unit, or an effects pedal such as an overdrive unit.

The concise summary is that the Red Box is a relatively inexpensive and very simple unit that does what it is supposed to do very effectively. It doesn't have the fancy controls of more sophisticated unit — indeed, it doesn't have any controls at all — but that doesn't detract from its usefulness.

Further Information
Red Box £59 including VAT.

John Hornby Skewes, (Contact Details).