Spring technology is still the most cost-effective way of producing reverb and if you can't afford to go digital, it's the only practical alternative. This month we examine the JHS SL5300.

The mechanics of spring reverbs are well known and their basic simplicity means that they can be produced cheaply without compromising too much on quality. A spring is driven into vibration at one end by means of a moving coil transducer fed from an amplified version of the input signal and these vibrations are picked up at the other end of the spring and converted back into an electrical signal before being returned to the outside world. For stereo operation, two sets of springs would be required, which are driven from a common source but their outputs are kept separate.

This very reasonably priced unit from JHS is mono in operation and is really a very basic device, although it does incorporate a built-in 3-band EQ section which can be of great help if your mixing system is somewhat limited in this department.

Layout

In order to conform to H&SR house style, the unit is housed in a 1U rackmounting case and is mains powered. The input and output sockets are located on the front panel, which can be inconvenient for connecting to a patch bay, but I would guess that the section of the market for which this product is intended will find it quite satisfactory in its existing form. It would be a simple matter to drill holes in the rear panel to fit duplicate sockets, but this practice is likely to affect your warranty to the point of extinction.

"...as an addition to a basic cassette multitrack system, it's a very attractive and cost-effective package."

There's a choice of high or low impedance inputs, enabling the user to connect either a line level input, an instrument, or suitable microphone direct. A Volume control sets the drive level to the spring but there's no metering system, so you'll have to rely on your ears to let you know if you're overcooking things. Reverb Depth adjusts the balance between the direct and the reverberated signal and for use with a mixer, and this control should be fully advanced so that you get only the reverberated sound at the output.

Equalisation comes next, and this consists of a conventional Bass, Middle and Treble control set-up, rather like the type found on instrument amplifiers and, though it is not particularly sophisticated, it's more than adequate to give you that extra bit of tonal variety.

"...as you might imagine, the unit isn't over-impressive when subjected to the rigours of the drum machine test, but that isn't at all surprising when you consider the price."

The single output jack socket is adjacent to the footswitch socket. This enables an optional footswitch to mute the reverb sound; a useful feature in a live situation. Power-on is indicated by a rectangular red LED and both the power switch and the fuse holder are located on the front panel. So much for what's on the box, but what's in the box?

Inside Job

Removing the lid shows the interior to be sparsely populated but nevertheless well constructed. A single PCB holds all the electronics and the transformer is mounted well away from everything else to minimise hum pick-up. The reverb spring itself is a short dual spring device about six inches long and is housed in a metal case, supported by foam pads to lessen the effect of vibration. So far so good, but the real question is how well does it work?

"Used at high levels, a certain amount of hum and noise is audible and it pays to drive the unit as hard as you can without incurring distortion in order to minimise this problem."

In Use

Well, as you might imagine, the unit isn't over-impressive when subjected to the rigours of the drum machine test, but that isn't at all surprising when you consider the price. All springs tend to twang to some extent and this one doesn't do anything to break with tradition, although it is just about usable on percussive sounds if its level is kept low in the mix. The EQ does help to some extent but does nothing to obscure the twang effects; it only helps to achieve a more useful tone, and this it does quite well.

On other sound sources such as synth or guitar, the unit performs somewhat more creditably giving a reasonably smooth result, and only the occasional low note with a fast attack caused the twangs to manifest themselves. Vocals present no real problem to the unit but the sound is still very coloured by the resonant frequency of the spring system.

"...you have to accept that you're not going to get an AMS for £80 which is about what this little box will cost you."

Used at high levels, a certain amount of hum and noise is audible and it pays to drive the unit as hard as you can without incurring distortion in order to minimise this problem. If the reverb sound is recessed in the mix, as is likely to be the case, this should present no real problem if the ultimate aim is to make demo tapes on a cassette-based home system, but it's unlikely that the performance in this respect will be up to the standard of a good reel to reel-based studio.

Conclusions

Whatever is said about this unit must be considered in the light of its very low selling price and as an addition to a basic cassette multitrack system, it's a very attractive and cost-effective package. The comments relating to its performance on drums and other percussive material are equally as valid when applied to other spring units, some costing rather more than this one, and unless you can stretch your budget to over £200 to accommodate a Great British Spring, you're probably as well off with this unit as any of the other budget offerings within this price range.

I would have liked to see a lower level of hum pick-up, but I realise the difficulties of trying to get a spring line and a transformer to share the same box without giving pick-up problems. The only way round this is to house the power supply in a separate box which would defeat the object of producing a neat rack mountable package, and the noise level isn't too serious for demo work.

After checking out the best in digital reverbs, it brings you down with a bump when you get a budget spring device to check out, but you have to accept that you're not going to get an AMS for £80 which is about what this little box will cost you. Within its limitations, the JHS reverb performs reasonably well and you can't quibble about the price. For those of you who find some of our review items a bit on the pricey side, this is one may be for you but it isn't going to satisfy the criteria of serious recording enthusiasts.

Further information on the JHS SL5300 can be obtained from: John Hornby Skewes, (Contact Details).