Is Small Beautiful?
The world’s best-known builder of modular studio effects has just introduced its entry in the sampling steeplechase. But will it fall at the first hurdle? Paul White has the answer.
Thanks to some clever software writing, Rebis' new RA226 sampler manages to put an eight-second maximum recording time and a load of other facilities in a very small box indeed. Sometimes, though, being neat and tidy isn't everything.
Most of you have probably already heard of Rebis. You haven't? You should have. Rebis are a British design and manufacturing company, big enough to make their products up-to-date and cost-effective, but small enough to make subtle changes to their designs as and when necessary, without having to bring out a MkII version.
The company specialises in outboard effects for recording studios, and specifically, the kind that rack within standard 19"-width cases to form an interlinked FX system that's as space-efficient as it is versatile.
Rebis' current range includes compressor/limiters, noise gates, delays, noise reduction units, and even an RIAA preamp that lets you plug a turntable/cartridge signal directly into a line-level mixer channel. Now they've introduced a sampler just to round things off. It's called the RA226 and it's... well, it's a bit of a mixed bag. It's well-built, it has an agreeable spec, and its price is fairly low. But it also has a number of curious design omissions that set it at a disadvantage when you start comparing it to some of the competition from musical, rather than studio, companies. Let's not get carried away, though. If all critics wrote their conclusions at the start of their reviews, half of them would be out of a job.
In its standard form, the RA226 will store up to 11 seconds of sound with an 8kHz bandwidth, though you can halve the time and double the bandwidth, or vice versa, if you need to. The stored sound can be played from a CV keyboard (you remember them), and the trigger inputs accept either V- or S-trigger formats, which covers just about everything.
The RA226 functions as a digital delay as well as a sampler, and if you don't have a keyboard or a sequencer with a CV output, you can still trigger fixed-pitch samples to create percussive sounds and similar effects. Control range over the CV input is two octaves, adequate for most musical purposes, but painfully limited by the standards of the Rebis' MIDI-controlled contemporaries. Theoretically, the long sampling time means that no looping facility is necessary, but we'll come to that later. In the absence of a loop function, you have the option to trim the beginning and end of a sample, and to build up a composite sample from separate slices of sound by joining several short samples together end-to-end.
The memory part of the RA226 is modular, which means that extra memory cards can be fitted to give a maximum storage time of 44 seconds with an 8kHz bandwidth or a staggering 88 seconds with a 4kHz bandwidth.
As we all know, when you play a sample from a keyboard, its pitch is changed either by speeding up or slowing down the speed of sample readout, so the length of the sample also changes. The Rebis way of doing things, however, ensures that when a sound is played back at a higher pitch, the RA226 automatically adjusts its output filters so that an 8kHz sample transposed up by one octave has a full 16kHz bandwidth.
Everything looks quite simple. There are six knobs, six buttons and six LEDs, all squeezed onto the 226's tiny front panel. There are two modes of operation — Sampler and Delay. Let's look at the latter first.
With the Pitch control set to +1 (fully clockwise), maximum delay time is 1.4 seconds with a 16kHz bandwidth. The reason the maximum delay time is far shorter than the maximum sampling time is that not all the memory is available; one area is reserved for sampling only, and anything stored in it is retained even when the unit is being used as a delay. The End control is used to set the exact length of the delay, and Feedback works in the customary way to produce repeat echoes.
"Facilities - Control range from a CV keyboard is two octaves, adequate for most purposes but limited compared to the Rebis' MIDI-controlled rivals."
You can store a sample simply by pressing the Record button, at which point the LED next to the button flashes. As soon as an input signal appears, the Rebis' automatic trigger circuit starts the recording process and the LED stays on until the recording is complete. The unit plays your sample back once automatically, so you can check its quality (or otherwise) as soon as the recording is finished.
Once you have an agreeable sample, you can replay it manually either forwards or backwards, though sadly, backwards replay isn't possible from a keyboard. So that you don't have to hold the relevant buttons down for the whole length of a sample, there's a Latch switch for playing the sample all the way through automatically. If you want to hear the sample loop continuously you press the Loop and Latch buttons simultaneously, while pressing Loop on its own allows you to step through the sample a section at a time.
Two rotary controls are what you use to vary the start and end points of a sample; if their positions overlap, a section in the middle of the sample can be removed and the two ends joined up again. As usual, joining any two sounds is likely to cause an audible glitch, so more often than not, it pays to adjust the edit controls for the least obtrusive join. The same goes for composite samples, which you bring into being by using the edit controls to define which part of the memory a sample is to be recorded into.
During the sampling process, the most important of the Rebis' many small controls is probably the one marked Pitch. A sample recorded with the Pitch control set to zero will be transposable up or down one octave, but a sample recorded with the Pitch control at +1 will only be transposable downwards (upwards for a setting of -1). The recording bandwidth is automatically modified according to the setting of the Pitch control, as is the sampling time.
So now the recording's over, and you want to get on with some music. The most obvious way to do this is by connecting a one-volt-per-octave keyboard to the CV and gate inputs, but things may not be quite that simple. You may find, for instance, that you need to experiment to find out which two octaves on the keyboard operate the sampler, as this varies from synth to synth. You use the Pitch control to fine-tune your sample to the keyboard.
Now, the Rebis is a relatively hi-tech machine, so I thought I'd marry it up with something a bit equally state-of-the-art, an ARP Axxe monosynth. I should have expected problems, and I got them. The Rebis was set to accept control voltages in the 2V-4V range, whilst the ARP gave out 0V-3V. The result? Only the top few notes would work. I rang Rebis, but obviously someone else had already linked up an antique synth, as they were well aware of the problem. Production models would be equipped with a means of matching up the CV input to different types of synth, they said.
Unperturbed by all this, I continued the test using a Roland MC202, which could be set to give a CV output in the right range. From then on, everything was fairly straightforward.
"Operation - Once you have an agreeable sample, you can replay it manually backwards or forwards, though backwards playback isn't possible from a keyboard."
Sampling a sound is made easy by the automatic trigger, though you do have to be careful not to make any unscheduled noises before the sound to be sampled comes around. Still, if you do capture a small amount of unwanted sound, you can remove it by adjusting the Start control until the sample starts exactly where you want it to.
One problem becomes evident quite early on, though. Samples with no natural decay curve tend to sound truncated when the sample runs out, or when the key is released. This is also true if a sample is shortened using the Edit controls; some sort of gentle fade-out, rather than an abrupt cutoff, would be more artistically acceptable. One way round this problem is to feed the output of the sampler back through the external audio input of the synth you're using (if it has one), and set the Latch status to On. That way, you can not only modify the envelope of the sampled sound, but also apply some creative filtering.
Then we come to the subject of noise. Any sampling system introduces some degree of quantisation noise, and whilst a lot of this can be masked by the sound of the sample itself, it's often audible at the tail end of samples, or when the sampled sound contains little in the way of high frequencies to block the noise. If anything, I'd say the Rebis' eight-bit resolution made it a little bit noisier than I'd expected; sampling has come a long way since the days of the abortive Movement Mimic, but although the RA226 didn't put out quite that degree of fuzz, the noise levels weren't as low as I would have liked, especially on difficult samples like bass guitar.
Again, though, a large part of this problem can be eliminated by using the filters in your synth. All you do is tailor the frequency response to suit the sample and arrange the filters to close down as the envelope decays, and lo and behold, the tail-end of your sample is far less noisy, leaving the sample itself more or less intact.
You can also get round the problem of not being able to play reversed samples from a keyboard. When I complained to Rebis about it, they said there just wasn't enough room on the RA226 to fit the extra switch needed. They would, however, be detailing a modification in the user manual, so you can attack the sampler with a soldering iron in the knowledge that what you're doing will probably result in your being able to play the first line of Cliff Richard's 'Devil Woman' backwards from a single note on the keyboard.
I'm still not convinced about this business of building up sounds by butt-jointing several short samples. The results sound messy, and it's almost impossible to avoid creating clicks where the samples join. Still, the majority of samplers seem to offer this facility so I can only assume that some people use it. And in truth, the Rebis is better than most I've tried, as its internal software joins the samples at zero crossing points.
You've probably already realised that I have mixed feelings about this sampler. As a primarily musical device, its short pitch range, lack of MIDI, and monophonic operation all count heavily against it, but the most serious omission is a looping facility. Long recording times (and the Rebis' maximum is very long) are no substitute for looping, because you can fuse them to repeat one section of a sample over and over again. For the price of the RA226, its full compliment of memory and a rack to put it in and power it from, you could have an Akai S612 complete with MIDI control, six-voice polyphony, and a disk drive to dump your own samples onto. No contest.
Luckily, the Rebis fairs better in the studio, where a lot of potential buyers will already have a suitable rack. Its long sampling time makes it a viable alternative to spinning-in short sections of music during recording, but even then, it could still be too noisy.
Prices RA226 basic unit £575; extra memory cards £216 each (up to maximum of three for 44 seconds at 8 kHz); 14 unit frame rack £115 including power supply. All prices include VAT.
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Review by Paul White
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