Hollis Research GX7 Guitar Amp Simulator
The search for the perfect guitar overdrive in a box continues: one of the latest entries into the fray is the GX7 Guitar Amp Simulator from Hollis Research, producers of the Trackman II friendly sequencing package for the Atari ST. The GX7 is solid state — no room for valves in a unit this size — and has some cunning circuitry that does its best to emulate the effects of valve amplification on the guitar's sounds.
Physically, the GX7 is nothing remarkable: a small black box with a couple of knobs, a jack input socket and a pair of stereo mini jack sockets. The two knobs control drive and level, but the business end of the circuitry is a row of eight little switches in a DIP package on the top of the unit; this is nicely screened with both the product's name and a list of the functions of the switches. The first two are used for setting up the input sensitivity — the GX7 can handle a wide range of pickup impedances. The remaining switches are labelled Presence, Soft Clipping, Clean Amplifier, HF Distortion, Close Mic Effect and Bass Boost Cancel. A bass boost makes the GX7 sound meatier when playing through headphones; the cancel switch turns the boost off when going straight into a mixer. The simple but concise user guide gives a few example settings to get you used to the different options (and note that 'on' for the switches is away from the word 'open' that appears on the body of the DIP package). The settings given, including 'Heavy Distortion', 'Close Miked combo', 'Large Stack' and 'American Rock Guitar', are excellent examples of what the unit is capable of.
Of the two stereo mini jacks, one is the main output, and can be used to drive a pair of stereo headphones or (with the supplied adaptor) to plug directly into a mixing desk; the other socket is a stereo auxiliary input, and is included just in case you feel the need to play along with records or backing tracks. The Auxiliary input signal is unaffected by the preamp processing.
The unit runs on a PP3/9V battery, and an alkaline battery should give around 100 hours playing time — the battery is wearing out when the LED starts going dim and your playing sounds crackly or weak. Plugging a guitar into the input turns the GX7 on, so it is rather important that you unplug your lead when not using the preamp.
Sonically, the GX7 works well, with headphones producing the least satisfactory results, though the sound was still fine for practice. Through a mixing desk and off tape, over control room speakers, the GX7 produced a very full sound with depth and warmth, not a million miles away from the real thing — the real thing in this case being a valve-equipped amp. Side by side with a valve combo, the GX7 managed to hold its own. It was designed with this in mind, and it sounds as if someone did a lot of side-by-side testing to get it right. The sound can be varied from clean, sustainy solo voicings through to grungy mayhem, with lots of variety in between — great for heavy chords, ditto for solos. Blues settings with just a touch of distortion are possible, and if you need lots of sustain for two-handed tapping, then look no further. Some of the best distortion settings came with the HF switch on, although this did bring up the noise somewhat, although not to a greater level than when miking up a guitar amp. The bottom line with any product, however — guitar processors perhaps more so — is the potential user's personal taste.
The only truly negative point I can make has nothing to do with the sound — it's the fiddly switches that get my goat. Obviously, in a studio or practice situation, there is time to fiddle with the tiny switches, but if you were to venture out live... you get the message. It's not impossible to change settings, but neither is it particularly convenient. I'm also not too keen on the output jack, since mini jacks don't provide the most secure of connections.
For the guitarist, the GX7 is a cheap new source of sounds to add to the arsenal, and for the home recordist, it offers an excellent way to get a decent, valve-type sound onto tape without rousing the neighbourhood — and it's great value.
Hollis Research GX7 £79.95 including VAT.
Hollis Research Ltd, (Contact Details).
Review by Derek Johnson
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