Does sampling still cost an arm and a leg? It needn't if you let Akai give you a hand.


The music biz is one of those areas where 'buzz' words are the key to a musician's conversational success. Favourites today are 'digital', 'MIDI' and 'sampling'. The Akai S612 is in that respect a real winner as it incorporates all these facilities in one neat 2U high, 19" rack mounting unit. It is digital in that it uses digital electronics, it is controlled via MIDI and it is a sampler. Not bad for a hi-fi company who have only recently ventured into the world of electronic music.

Introduced at the Frankfurt Fair this year, the S612 caused a few 'oohs' and 'aahs' to be uttered (which were then presumably sampled) by an impressed audience. Impressed not only by its excellent performance, but also by its price. Although its RRP of around £1100.00 represents a substantial investment for the average musician, it's still a fraction of the cost of any currently available alternative and so is an effective way of getting into polyphonic sound sampling if you're on a tight budget.

It astonishes me that once something is unveiled at Frankfurt, the musical fraternity grinds to a halt, incapable of working without the latest Japanese wonder product, but be that as it may, the S612 (what an imaginative name) is an impressive package and any reservations I may have are largely based on the technique of sampling in general and not on the instrument itself.

Sampling, for those of you who have just returned from a ten year pilgrimage to the third moon of Tranthax is a process whereby any sound can be stored in digital memory whence it can then be 'played' in a musical manner via a keyboard. In theory, this is a splendid idea and I wish I'd thought of it. In practice however, it's not that simple.

Digital memory and the software to control it is pretty expensive and so only a short burst of sound can be stored without the unit costing an unreasonable amount of cash. The usual sampling time provided is only a few seconds which in itself is not so wonderful. To overcome this problem, a system of looping has been devised that, in theory, allows infinite sustain. Again, in practice, this technique is fraught with problems. Because of the complexity of even the simplest sound, it is often difficult and sometimes impossible to find a good point to loop from. The end result in these circumstances is something that sustains with a noticeable, repetitive glitch.

The second problem related to sampling is based on the way the sound is actually replayed. Samplers work on much the same principle as a tape recorder. Speed up a recording and not only will it be higher in pitch, but it will also be shorter in length (the converse is also true). As a result, higher pitched sounds will be very much shorter than lower pitched ones. Granted, many acoustic instruments exhibit similar characteristics, but with sampling the effect is far more drastic - twice the pitch equals half the length and vice versa. Holding a chord down on a sampler means that the higher notes will die away before the lower ones unless you use the looping facility - not an ideal situation. Coupled with this is the fact that whenever a sound is played a few tones above the pitch of the original sample, the sound begins to sound a bit 'Mickey Mouseish' and sounds pitched lower sound sluggish. Multisampling, a technique whereby several samples are taken of the sound across its pitch range so that the sampled deviation is never more than a few semitones, cures all this, but is far too expensive to include in machines at this end of the market. Despite all these drawbacks, sampling is something that many musicians would bite off their own heads for - hence the development of the Akai S612.

Layout

The unit is smart and sleek, possessing only a few controls and switches and an assortment of sockets. The design is very Yamaha-esque, utilising the pink, purple and turquoise livery of the kings of FM. To the left of the units front panel are two jack inputs, one for mic and one for line levels and above these are two controls for setting the level of the input signal and for monitoring the incoming sound; these are used in conjunction with the horizontal LED bargraph meter to be found in the centre of the unit.

To the right of this central panel are 7 rotary controls which can be used to refine a sampled sound, but more of that anon. The central section is the nerve centre of the S612 for it is here that you can order the unit to sample, overdub, loop, select MIDI channel and load and save sounds onto the optional disk drive.

Operation

The Akai is extremely easy to use and to get a sound into it you simply press the 'NEW' button (of the touch membrane variety similar to those used on Yamaha DX synths) after having set the input level so that you get as much level in without distortion. The LED to the left of the 'NEW' button will go on awaiting your noise. As soon as you hit, scrape, blow, drag, punch, destroy or pluck your object, the LED begins to flash (faster or slower depending on the sample time) for the duration of the sample time and goes out as soon as the memory is full whereupon the unit automatically goes into the play mode. Providing you have a suitable MIDI keyboard connected you're in business to go about your 'Art of Noise' impersonations.

If you're not happy with the sound, you simply repeat that process again until it's right. You can also overdub sounds by pressing the 'OVERDUB' button so layered sounds and all sorts of exotic combinations can be achieved. This feature is useful in turning your single, feeble 'AAAH' into the massed voices of the Tabernacle choir and for layering car crash violins, etc , without resorting to multitrack. Care must be taken not to drown the original sample with your new sound as there is no way to isolate the overdub and have another go so you'll have to start from scratch.

It's in this record mode that the Akai boxes real clever. On many samplers you are given the option of lengthening the sampling time for longer sounds, the trade-off being that your bandwidth and/or quality is reduced. The Akai is no exception except that whereas most other samplers require that you define the sampling time yourself using some form of control parameter, the Akai appears to make the decision for you. The sampling time seems to vary from around one to five seconds and at first we thought that the machine was weighing up the harmonic content of the input in order to determine the optimum sampling time. This seems unlikely however and a more likely explanation is that as we received no handbook, there are still secrets to be uncovered concerning the way in which one sets up the sampling time.

Once your noise is in the machine, you can start to have some fun with the controls.

Directly to the right of the level meter are two horizontal sliders which, in conjunction with the three turquoise membrane switches beneath, are responsible for looping your sound. The top slider is labelled 'START' and the lower one 'END'. Referring to Fig. 1 will show a typical envelope before looping. Points A and B can be selected anywhere along the time axis so that looping can be effectively achieved anywhere in the sound.

Associated with these controls are the three mode select switches beneath them. The first button is labelled 'ONE-SHOT' and simply plays the sound back without looping although fiddling with the two sliders provides some interesting editing facilities. Moving the 'START' slider forward will chop off the front end of the sound (too far forward and the sound will be cut off completely which can cause a bit of confusion if you haven't got your wits together). If you move then 'END' control to the furthest left of its travel with the 'START' point control moved to the right, the sound can be reversed so that it is played backwards. Quite how this takes place is beyond me, but suffice to say, it works and can be a lot of fun.

The second button is labelled 'LOOPING' and the two sliders then set the looping points as in Fig. 1. The other button is labelled 'ALTERNATIVE' and is a very interesting inclusion on a unit of this price. Whereas 'LOOPING' cycles the sound A-B, A-B, A-B, etc , 'ALTERNATIVE' loops the points A-B, B-A, A-B, B-A, etc. This second mode of looping makes for much smoother looping and makes it a lot easier to set up loops that are practically glitch free.

Having said all this, however, looping is still a bit of a fiddle, but the Akai is no worse in this respect than other, more expensive instruments and any problems you may experience are usually the fault of the sound and not the unit.

Further refinements can be made to the sound using the controls to the right of the centre panel. The top three controls introduce vibrato via 'RATE', 'DELAY' and 'DEPTH' potentiometers - a neat idea if your MIDI synth doesn't transmit modulation down the MIDI line and is a neat way of hiding the glitch in a loop. The bottom controls are labelled 'FILTER' - a very sharp acting low pass filter - and 'DECAY' which allows you to add a bit of 'overhang' to your sound after you take your fingers off the keyboard. Filtering is not included simply as a tone control enabling you to gratuitously lop off unspecified amounts of treble but rather to let the user determine the optimum compromise between bandwidth and quantisation noise. The other control in this batch is simply an output level control though there is also a 'TUNE' control for fine tuning the sound to other instruments.

Although these controls offer a goodly amount of variation, I would like to have seen more in the envelope shaping department, particularly some form of attack control for softening the start of sounds you have sampled. I see no reason why this couldn't be done as there are already envelope shaping facilities on board - adding an attack control would add very little extra expense so how about it Akai? The unit does however respond to MIDI velocity information which is a most welcome addition.

The Akai's official title is 'MIDI Digital Sampler' and its intention is to be controlled by another MIDI unit. This could be a keyboard, a sequencer, the new Roland guitar synth, a drum machine or even MIDI drum pads. The idea of not including a keyboard is quite a good one as I would imagine that this unit will be bought by people who already have a MIDI synth and so some money can be saved there. Alternatively, if a guitarist or drummer wish to use the unit they don't have to fork out for an unnecessary keyboard. I do feel sorry for people who don't have any MIDI facilities but want to use this instrument, and it would have been a good idea to include 'conventional' cv and gate inputs so that it could be interfaced with older synths and sequencers, Micro-Composers, etc, though to be fair, not many polyphonic machines have CV and gate outputs. The centre panel also features MIDI assign buttons (again, of the touch membrane variety). These are 'CHANNEL UP' and 'CHANNEL DOWN' and are used to assign up to 9 receiving channels (as it has no keyboard, it cannot transmit). Quite why Akai have decided on 9 channels is a mystery as is the reason for having two channel incrementors as it's possible to get any channel you want using only one. Alongside the MIDI selectors is a MONO/POLY selector although it doesn't work in any logical way. It doesn't assign all 6 voices to one note and neither does it behave like a conventional mono-synth so I'm not so sure of its usefulness. Perhaps the manual will make these grey areas rather more clear when it finally materialises.

Grey Areas

Underneath these three buttons are a further three which operate the optional disk drive. They allow you to save, verify and load sounds to and from disk for quick and easy retrieval of sounds. Possibly, the disk will store all your loopings settings and maybe other parameters such as MIDI channel and maybe even control settings. At the moment, our information is vague so I can't be sure. Whatever, the disk drive is likely to sell for about £350 or so. In the absence of the disk drive, you can store your sounds by recording them on quarter inch tape, but you will have to go through the process of loading, looping etc, every time.

The back panel is a little bit confusing, especially with no available literature. There is a big section cutout which accommodates a large edge-wise multipin connector and a smaller multipin socket. It's not quite clear what these are for, but I can only imagine that one is for the disk drive and the other for connection to some other peripheral such as a VDU for waveform display (and editing, perhaps?) or a computer for software updates such as multi-sampling, touch sensitivity or whatever. Only time will tell I suppose, so watch out for developments.

Also on the back are the three MIDI sockets, IN, OUT and THROUGH. As the S612 has no integral keyboard I see no reason for the MIDI OUT - maybe that is there for future development as well. As no information was available when I reviewed this, it's only conjecture on my part.

Also on the back of the unit I was given two tiny buttons and a little LED. Apparently, these two buttons will be on the front panel in production models, one relates to the looping controls whilst the other allows octave transposition of the stored sound.

Conclusion

In conclusion, the Akai S612 is a doddle to use. Any sound you can think of can be used as a musical instrument and with 12 bit sampling at a maximum bandwidth of 12kHz the sound coming out is much the same as the one going in. The unit is pretty quiet although I did detect a certain amount of quantisation noise in sampled sounds, but I doubt if this would be heard amongst other instrumentation. The sound is uncoloured and generally very clear and so I've got no complaints there. In all, the unit is an extremely good sampler and offers facilities only rivalled by far more expensive instruments. If I have any criticisms they are that I would like to have seen CV's and gates fitted, would like to have had more sophisticated control over the envelope and maybe even multi-sampling or some form of split facility. At around £1100 it will sadly remain out of reach of many potential users, but it could be that it will sell for less than the RRP when it hits the shops.

The new Ensoniq Mirage, when it finally arrives, will be the Akai's nearest competition, even though it will retail at £500 or so more, but that price does include a keyboard.

With only a few reservations then, the Akai gets the HSR seal of approval for value and quality - it remains only for Akai to get these machines into the shops before any serious competition arises.