Roland Micro Cube

The diminutive Roland Micro Cube amplifier models a number of popular guitar amps using Roland''s COSM modeling technology. The Micro Cube weighs a mere 7 pounds, 5 ounces and can operate on six AA alkaline batteries or an AC adaptor.

For guitarists and owners of small recording studios alike, the Roland Micro Cube amplifier ($149) is a dream come true. The tiny, feature-packed Micro Cube employs Roland's COSM digital modeling to deliver convincing emulations of some of the world's most revered guitar amps, without hogging floor space or forcing you to become a professional weight lifter.

The Micro Cube weighs a mere 7 pounds, 5 ounces (excluding batteries or power adaptor) and measures only 9⅝-inches wide by 815/16-inches tall by 69/16-inches deep. The Micro Cube can operate on six AA alkaline batteries for about 20 hours. An AC adaptor is also provided, and the amp is shipped with a secure carrying strap attached.

To Good Effect

The Micro Cube has a rotary switch that selects among six COSM amp types: Roland JC-120 Jazz Chorus, Fender Twin Reverb, Vox AC-30TB, Marshall JMP1987, MESA/Boogie Rectifier, and Acoustic. The latter is an acoustic-guitar emulation, but to my ears it produces electric-guitar tones more reminiscent of a DI box. A seventh switch position lets the amp accommodate a dynamic microphone — using the same ¼-inch mono jack used for electric-guitar input — but I found it also provided an interesting guitar tone. Separate volume, gain (overdrive), and tone controls further sculpt the dry sound.

A continuously variable EFX control dishes up mono chorus, flanger, phaser, and tremolo effects, all of which are of good quality. As you rotate the EFX knob clockwise, each modulation effect increases in depth and rate until it switches to the next type of effect. Turning the separate Delay/Reverb control progressively clockwise produces delay with an increasing delay time — from very short slapback echoes to around six repeats at intervals of roughly 400 ms — and then delivers reverb with increasing wetness and a fixed decay time of roughly four seconds. The reverb is fluttery but provides a nice enhancement for practice sessions. The EFX and Delay/Reverb controls have Off (no effect) positions.

A touch-sensitive, digital tuning fork joins all of the aforementioned controls on the Micro Cube's recessed top panel. The harder you tap the tuning fork's Touch Sens button, the louder the tone it produces. A three-way switch selects either an A (440 Hz), A-flat, or A-double-flat (G-natural) tone, which rings for about 11 seconds before gradually fading to silence.

The Ins and Outs

The collection of jacks on the Micro Cube's rear panel allow you to use the amp as either a direct-recording device or as a personal practice amp. The ¼-inch TRS Rec Out/Phones jack can be used to deliver a direct line-level feed to your mixer or recording device, or it can be used to power headphones for silent practice sessions. (Plugging a connector into this jack mutes the Micro Cube's speaker output.) The jack's output is mono, although its TRS topology enables signal to be sent to both left and right headphone channels.

The jack's output was sufficiently loud when used with Audio-Technica ATH-M40fs headphones, but it was at least 9 dB too low (depending on the amp's settings) to achieve 0 dBfs input to my Apogee Rosetta A/D converter (even with the latter's calibration trims maxed). You can use an outboard processor, such as a compressor, before your A/D to provide additional make-up gain. The Micro Cube's direct-out sound, while good, was not nearly as warm and creamy as that produced by the unit's flattering 5-inch speaker.

The rear panel also includes two parallel aux inputs — stereo ¼-inch and mini phone jacks — for patching the left and right outputs from, say, a CD player or cassette deck into the Micro Cube (using a Y connector). Listening to a mix of the aux input and my live guitar (either through the Micro Cube's headphones jack or speaker) was useful in developing guitar arrangements while playing to rough mixes. However, the aux-input signal is summed to mono, and there is no volume control for it. This omission is understandable considering the Micro Cube's rock-bottom list price, but you might need to use a playback deck with output-level control in order to keep the Micro Cube's aux input from being uncomfortably loud.

It's a Scream!

Even with a rated power output of only 2W, the Micro Cube is plenty loud. But best of all, the amp produces virtually no added hiss or hum when its volume and gain controls are fully boosted. I am absolutely stunned by how great this little amp sounds, and the price is right.

Overall EM Rating (1 through 5): 5

Roland Corporation U.S.
tel.: (323) 890-3700