There comes a time in every musician's life when it's helpful to know the tempo of a particular piece of music. This could be the tempo of a solo in a concerto, the speed of a track on a demo tape, or whatever, but, until recently, there hasn't been a means of estimating this other than by using what could be called a successive approximation technique with a metronome, i.e., fiddling with it until the clicks just about fit. The Tempo-Check produced by Pulse Designs, a British firm, enables this to be measured with ease and offers a lot more to boot. Measuring 6¾" x 2½" x 2", the sensible wedge shape of the Tempo-Check makes it very stable in those situations where other units would merrily bounce on to the floor. It's perhaps not surprising to find a microprocessor responsible for its activities, but it is rare to find quite so much flexibility in such a compact package.

To start with, the unit offers a chromatic octave (middle C to B) of tuning pitches (referenced to A = 440 Hz), the output being of square wave variety and heard through either the built-in speaker or via an earphone socket. The transparent main control is used to select the pitch and this value is also displayed on the large three-digit LED display in the middle of the Tempo-Check. Some tuners on the market provide chromatic pitches in different octaves and allow for very precise null adjustment of the tuning via a mike input. I've never actually found it necessary to reject my ears in favour of a beat-detecting machine, and so I found it utterly straightforward to tune both a 6-string guitar and a 46-string harp from the 12 pitches of the Tempo-Check. Automation isn't always the answer — especially when tuning such obtuse things as harps which require you to slightly sharpen notes at the top end and flatten those at the bottom!

Measuring tempi is merely a matter of sliding a switch from 'pitch' to 'beats', pressing the red 'tempo' button in time with the music, and reading the display a short time later. Tempo indication is obviously not instantaneous as the processor needs at least two points with which to calculate a time interval, but, in practice, the delay is inconsequential unless the tempo you're measuring is itself fluctuating — in which case you've got problems!

I managed to register tempi from 5 to 500 beats per minute, so it should do the trick for any piece of music you care to tap into its Design Centre-selected case.

On first switching on, the metronome side of the unit ticks away in a thoroughly familiar manner with the main control selecting tempi ranging from 40 (grave) to 200 (presto) and displaying the same on the LED display. At this point, one also notes three LEDs ('downbeat', 'beat 1' and 'beat 2') above the main display flashing in synchrony. The really interesting things start happening when you press the 'beat 1' and 'beat 2' buttons. Pressing 'beat 1' and at the same time adjusting the main control results in the number of beats per bar being indicated on the display. Releasing the button results in the resumption of beating but with the red LED indicating the downbeat and the yellow LED the beats per bar. The 'beat 2' button can then be used to program in sub-divisions of the beats per bar in the same way as for 'beat 1' and the green LED then joins in the metronomic fun of the other two. As well as visually and audibly indicating sub-divided beats, the Tempo-Check also makes it child's play to enter cross rhythms, ranging from straightforward things like 3 against 4 to such physical and mental demoralisers as 11 against 12. Each of the three beat indications has a slight difference in pitch, and, furthermore, the balance of the three sounds can be varied according to the volume setting. I've used the earphone output of the Tempo-Check to provide a click-track on some recent recording sessions and I'm pleased to report that it really works extremely well.

A definite plus point of the Tempo-Check is that it uses rechargeable Nicad batteries rather than requiring you to be perpetually replacing batteries in a unit that accidentally got left switched-on. Would that more manufacturers adopted a similar policy with effects units!

Whereas the pocket-sized Tempo-Check is designed and priced (around £55) for the musician on the move, their other version, the Tempo-Check TCS 120, is a 19" rack mounting unit with a rather more solid price (£270 + VAT). This is intended for studio applications and includes a number of extra facilities in addition to those offered by the cheaper model. Tempo measurement and tuning follows the previous plan of action, but an optional tuning input card enables the TCS 120 to be used both as a tuning reference and as a tuning meter with the tuning error shown on the left hand digit of the display as a series of dashes.

On the metronome side of the TCS 120, the unit offers tempi references of frames per beat (for TV and film work) as well as the usual beats per minute. An instant start control (triggerable from a variety of sources) and multiple pulse and timing controls make the unit very easy to interface with sequencers, synthesisers, and so on. Instead of the rather boring click characteristic of the other Tempo-Check and electronic metronomes in general, the TCS 120 provides a much more interesting high-pitched drum sound. In addition, separate downbeat, crotchet, triplet and quaver outputs can be blended together with front panel controls to give musicians a rather more lively click-track foldback that's also easier to follow.

An excellent unit, the TCS 120, but I'm perfectly happy with the poor man's version. So, 'bye for now — I'm off to practice playing 11 against 12!