NanoCompressor

The Alesis NanoCompressor was launched in 1996 as part of the Nano range of 1/3-rack-space project studio devices. As far as I can tell, it’s a scaled down version of the component compressor from the incredibly successful Alesis 3630 (introduced in 1991). The 3630 incorporates two of these compressors, both with its own noise gate, whereas the Nano is just a single one, without a gate.

So, the NanoCompressor is a tiny box which is most unlikely ever to be accused of taking up too much room in a studio. It's very simple and well laid out, with stereo ins and outs on the rear, plus a single ring/tip jack for a side chain. On the front, the user controls are as follows...

The Threshold sets the volume at which compression will kick in. The further to the left you turn this knob, the lower the volume at which compression will kick in, and accordingly the more compressed the sound will be – subject to the setting of other controls.

The Ratio controls the actual amount of compression – how much the sound is squashed. But these controls work interactively, so once again, the result as it sounds to the listener will depend on the setting of the other dials. With the Ratio knob set all the way to the left, there will be no compression at all. With it set all the way to the right, the sound will potentially be heavily squashed – subject to the setting of the other controls.  

Attack determines how quickly the compression kicks in after the strike of a note. With the Attack knob set all the way to the left, the effect is introduced almost immediately. With it set all the way to the right, the initial strike of the note is allowed through without compression.

Release determines how quickly the compression dies away after the strike of the note. All the way left, only the initial attack of the sound is compressed. All the way right, the compression remains active for three seconds after the initial attack, before fading away to leave the natural sound.

Finally, the Output allows compensation for any drop or rise in signal level once the compression settings have been determined.

There are selection buttons for Hard or Soft Knee compression, and Peak or RMS mode. Hard Knee just means the sound is strictly governed by the Threshold setting and will be immediately compressed once volume raises above that threshold. Soft Knee gives a little more ‘licence’ and makes the overall feel less ‘mathematical’. In Peak mode, the NanoCompressor performs as a strict limiter with a ceiling on volume set by the Threshold level. This prevents any loud transients in the playing from exceeding a desired maximum level, thus protecting recordings against unwanted distortion. In RMS mode, the dynamic squeezing is based on the average level of the signal, so things don’t sound so contrived or viciously compressed. RMS mode, however, disables the Attack and Release controls, and sets its own times. There’s also an Input/Output selector button, which allows you to choose whether the LED meters represent input or output levels, plus a Bypass, should you want to switch off the effect.

Here you find 7 models, 7 with images and 0 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from Alesis; Rhode Island