Yamaha SU700

The SU700, Yamaha's entry into the 'groove sampler' stakes, is derived from their A3000 studio sampler and inherits some of its sibling's most impressive features — including adventurous effects and imaginative sample‑manipulation facilities — while adding quite a few tricks of its own. Derek Johnson and Debbie Poyser go loopy.

Since Yamaha dipped their corporate toe back into the sampling waters with the tiny SU10 in early 1996, there's been no stopping them: '97 saw the A3000 (their first fully fledged professional sampler since 1988's TX16W), which was updated to V2 status just a year later. Less than a year after that, we're looking at a new Yamaha sampler in the 'groove machine' mould.

At the heart of the SU700 is a sampling engine derived from the A3000, but the instrument itself is a very different beast, being aimed at the performance/DJ market as well as the studio market. One look at the box should tell you what Yamaha are going for: it's cute and chunky in a (dare we say it?) 'Roland' kind of way, with rectangular rubber pads in pastel colours which remind one of the pastel‑coloured buttons on Roland's Juno 106, and its sequencer transport buttons are the sort of square, old‑fashioned machine controls you used to get on Roland Microcomposers. Somehow there's also a vaguely TR808‑ish feel about it...

This is not to detract from the achievement of Yamaha's packaging division in any way: the SU700 looks very cool and, as Apple have discovered to their profit from the success of the iMac, once you get the consumer to covet the goods because of their appearance, that's half the battle won! What seems a missed opportunity is that Yamaha's own RM1x groove sequencer/tone generator (reviewed in SOS February 1998) is so dissimilar in appearance to the SU700. Seemingly, they'd make a good team (and, indeed, we hear that shops are going to be supplied with racks to display the two together), so wouldn't it have been neat if they'd matched?

What's In The Box?

The SU700's front panel has a healthy complement of knobs and buttons to facilitate editing and real‑time control. The display's channel level meters double as a stereo input level meter during recording.

Having dealt thoroughly with how pretty the SU700 is, let's turn to the really important bit: what it offers.

Yamaha describe the type of sampling available in the SU700 as 'phrase' sampling, and it is combined with synthesis facilities, three effects processors, and a simple sequencer (externally sync'able via MIDI clock or MTC) that allows you to build up a composition from sampled phrases and hits. Factory sample memory is 4Mb, yielding between 44.6 seconds of mono (or 22.3 seconds stereo) 16‑bit sampling at the top rate of 44.1kHz and 357.2 seconds (almost six minutes) of mono 8‑bit sampling at the lowest 11.025kHz rate. In the middle there's a 22.05kHz sample rate, though if the optional AIEB1 board, which includes S/PDIF digital I/O, is installed, rates of 32 and 48kHz are also available. The memory complement is upgradable to a maximum of 68Mb (including the factory 4Mb), which would yield over six minutes of 16‑bit stereo sampling at 44.1kHz. With the full memory installed, the SU700 would be a great tool for remixing your own tracks. Installing the digital I/O board (which also adds six analogue audio outputs to the pair already on the SU700) would then enable direct‑to‑digital mastering of a remix.

The other SU700 option is the ASIB1 SCSI board, which allows a SCSI drive to be attached, for accessing sample CD‑ROMs, say, and for storage. A hard drive for the latter purpose would be pretty much essential with the full 68Mb of RAM, because although the SU700 has a very welcome DD/HD floppy drive, you don't get that much sample material on a floppy disk. Having said that, anyone who didn't want the extra expense of a hard drive and was prepared to juggle floppies (large memory dumps are split over several) could probably manage without one. You do have to save data at the end of every session, because the SU700's memory is volatile.

Lots of real‑time control is available via 12 assignable knobs, which also come into play for mixing, and a Ribbon Track that can alter any one of a number of sound parameters. The large fluorescent display uses four colours co‑ordinated (approximately!) with the control knobs and pads, so it's easy to see what you're doing, and a 'Job Grid' is provided for sample and sequence editing tasks, plus general housekeeping and saving functions.

On the back panel there's MIDI In and Out (but no Thru), plus stereo audio ins and outs. The ins can be used to mix external audio with SU700 Songs, and this audio can be treated with SU700 effects. Since the audio inputs can function at mic level as well as line level they could be used to sample a voice directly, or mix talking or singing with an SU700 Song in a live context. There's no need for a PSU socket because the SU700 rejoices in an internal power supply!

Studio users wanting to integrate the SU700 into a larger MIDI setup, however, may be a little disappointed with its MIDI spec, which is so basic in the area of external controllability that it almost makes the SU700 a closed system. To be fair, though, Yamaha probably see the SU700 as an all‑in‑one tool.

Studying Sampling

The SU700's jack inputs can be used for sampling and for processing external audio via the onboard effects.

The SU700 stores a maximum 40 samples per Song, in four banks of 10. There's no limitation on the length of individual samples, other than that imposed by the amount of RAM that's installed. Samples are triggered by 10 of the rubber pads running across the bottom of the front panel. There are actually 12 such pads on the instrument, but the last two are related to the audio input and the sequencer's Master track (more later).

Sampling could hardly be easier than with the SU700. With a sound source connected, you simply press the square 'Sampling' button, hit one of the pads to select a sample location (and at the same time a sequencer track, because sampling and sequencing are inter‑related), press the 'OK' button, which takes you to the sampling page in the display, and set bit depth, sampling rate and mono or stereo operation. Hit the 'Sampling' button again, play the source material and the SU700's off. The multi‑coloured columns in the display, which usually simulate 10 faders or meters showing levels on the vertical axis, change into stereo level meters on the horizontal axis. If the audio level is too hot, you'll get red sections at the right of the meters and eventually a 'CLIP' indication in the display. It's painless.

The SU700 divides samples/sequencer tracks into three types, with different‑coloured pads to trigger them and different characteristics. This seems slightly odd, but it's there, so it's best to have some idea of what you want to do with a sample before assigning it to a pad/track.

• Loop: samples on Loop tracks loop automatically as long as their pad is held down. (The SU700 does the looping, though you can crop the sample to make the loop work properly if needed.) They also loop automatically when a sequence is playing, without the need to hold down the pad. Yamaha envisage Loop samples (of which there can be up to two in each sample bank, and thus up to eight in a Song) forming the 'bed' of a composition. A sampled drum pattern or 4‑bar bass line, say, would be ideal in a Loop location.
• Composed Loop: samples assigned to these four tracks loop only when a Song is being recorded, for as long as you hold the pad down. These could be used to add further rhythmic material, or loop atmospheric sound effects.
• Free: samples assigned to the four Free pads can't be looped, so will probably be one‑shot samples or single hits, or even musical notes. As the SU700 manual says "these pads are great for punctuation your song with odd, effect‑type sounds." The Free pads are also your opportunity to introduce pitched sounds for playing simple tunes — a bass line could be sequenced using these, for example, though each pitched sample would occupy its own pad. However, there is a way to fake more complicated musical material, by using the sequencer's Scene memories (see the 'Making Tracks' section, later, for more on Scenes). For example, you could sample a bass sound, and record a part, with its pad, that plays what you want rhythmically. Now, using Scene memories, save up to eight transposition settings, then put the sequencer into record, triggering the Scenes with the desired transposition when they're needed. Result: instant bass line from a single sample. There are restrictions with this method, but it's do‑able.

Editing Issues

Sample‑editing facilites are not extensive but are sufficient. It's possible to trim start and end points, for example, though if a sample has any silence at the beginning, the SU700 automatically moves the sample start point past the silence to the start of the audio you presumably want to hear. There's no waveform display, so working out the start and end of a sample involves altering some pretty big numbers — which is how samples are shown in the display — and checking the result by ear. Yamaha have thoughtfully provided different resolutions for altering sample start and end points: it's not necessary to move in single‑sample steps (steps of 10, 100, 1000, 10,000 and so on are possible), and changes are always quantised to the nearest zero crossing, which helps to avoid clicks.

DSP options comprise trim (the unwanted audio either side of start and end points), reverse, normalise, frequency convert (to reduce sampling rate), bit convert (to reduce a 16‑bit sample to 8‑bit) and a stereo‑to‑mono option. The latter involves losing the left or right channel, mixing the left and right channels, or, interestingly, subtracting the right‑channel waveform from the left. This has the effect of removing any audio the two sides have in common; the manual suggests that it might erase some or all of a vocal from a sampled song. It also then mentions the word 'karaoke', but we'd rather not consider that eventuality. Note that some of the DSP functions can be slow on long samples, particularly frequency conversion. Resampling is also possible with the SU700 — see the 'Sample It Again, Sam!' box for details.

Samples can be further honed using a collection of mixing and synth‑like parameters, plus a set of 'Groove' parameters, all of which are altered using the knobs under the display. Pressing the button related to any of these features causes their function to flash in the display, at which point the knobs control that parameter. Level, pan and pitch can be edited in this way, as can LFO, sample attack and release times (the release parameter can make a sample continue playing without the user having to keep a finger on a pad), the SU700's resonant filter and 2‑band EQ.

The trio of 'Groove' buttons in the same area accesses Timing, Velocity and Gate Time parameters, which work directly on samples and are nothing short of amazing with the right source material. Timing adds 'swing' to a straight sample; with a rhythm loop sample you can hear swing being added in real time, as individual drum hits are moved. There must be a pretty clever algorithm in there, analysing the waveform, identifying rhythmic peaks and then moving the digital audio around, incredibly fast and with minimal effect on sound quality. Just as with quantisation on a MIDI sequencer, different note resolutions are offered: quarter, 8th, 16th and 32nd.

Moving along, the Velocity parameter alters the attack of various hits in a sample, and Gate Time shortens (or lengthens) the apparent time each hit in a sample lasts. The effect of both is remarkable and, again, for the most part artifact‑free. Speaking of remarkable, when you change the tempo of an SU700 song, loops are automatically time‑stretched, in real time, to fit the new tempo; the pitch doesn't change, and there are virtually no audio artifacts.

There is one small problem with the SU700's sample organisation: samples can be copied from one pad to another within a Song, but not from one Song to another, so using a favourite loop in more than one Song isn't as easy as it could be. There is a workaround: samples can be loaded off disk from inside saved Song files, though since samples can't actually be named (they're identified by cryptic references to their pads), you'll have to keep notes so you know what you're loading.

Examining Effects

Effects are another area in which the SU700 does rather well. There are three processors, all configurable as system or insert effects. The treatments available from the 43‑strong collection, which is derived from the A3000, depend on whether you choose insert or system operation, but you can have three global effects, or three insert effects (which can treat multiple tracks/samples anyway, but with no send control) or any combination of the two types. It's even possible to apply effects, including insert effects, to audio piped through the external inputs. There are some flexible routing options, too: Effect 1 has a send control to Effect 2 and 3, and Effect 2 has a send control to Effect 3, so if serial effects are required, or an insert effect would benefit from a little reverb, it's possible.

On the quality front, the effects collection is fine. The standard delays and reverbs are nothing exceptional, but they do a good job, with just enough variety. Delays — and many other effects — can be sync'ed to the SU700's master tempo, with a choice of time divisions that can be set independently for each effect you'd like to sync.

Where the SU700 really scores is in its creative treatments, which include strange modulation options and more ways to add noise and distortion than any sane person could want.

Where the SU700 really scores is in its creative treatments, which are mostly available as insert effects and include strange modulation options and more ways to add noise and distortion than any sane person could want. Some of the tamer ones are flanger, phaser, chorus, record noise, radio noise, and auto‑wah plus distortion. 'Noise Ambient' enhances the width of a stereo sample, then does mean things to it with noise, modulation and delay. Excellent! 'Jump' is a really odd one that chops up a sample, changes its pitch, modulates it and plays it back in a different order. 'Auto Syn' is fabulous on a melodic sample, producing a wild gated synth effect. Yamaha should put these effects in a box by themselves, because many of them have serious weirdness potential! It's worth keeping in mind that existing samples can be resampled with any strange or useful effect, freeing up the processor for use elsewhere.

The only negative on the effects front concerns the pitch‑shift insert effects: considering the incredible quality of the live time‑stretching, it was disappointing to find that these are not very good. They add a nasty edge to a sample — and not a nice nasty edge!

Making Tracks

Yamaha describe the SU700's sequencer as having 42 tracks — 40 sample pad/tracks (10 pads in four pad banks), plus the audio input track and the Master track. The audio input track records presses of the pad that mutes and unmutes audio throughput, and level and effects tweaks on that track, while pressing the Master track pad mutes all samples. The Master track also records master volume changes, Scene events and global Loop Restarts (more on the latter two in a moment).

Each sequencer track simply records the events associated with its pad, including pad hits, knob movements and track mutes (using the option which turns the pads into mute/unmute switches). You can also record Loop Restarts, which cause playing loops to start over (selected tracks or all loops globally), and Rolls — continuous rapid retriggering of the start of a sample. How much of the sample retriggers depends on the sequencer quantisation level selected.

Two record modes — Replace and Overdub — are offered. All previous events on a track are erased if you record on that track in Replace mode, and the new material is added to the old in Overdub mode. As you'd expect, there's a quantise option, so that events automatically fall to the nearest note sub‑division; quantisation can be set to whole, half, quarter, 8th, 16th and 32nd notes, with triplet variations. Overall, the sequencer's resolution is quoted as 480ppqn, with no quantise selected, while its tempo range is 40‑299.9bpm; tempo can be selected with the alpha dial, or by tapping the BPM button. The latter option lets you make a stab at sync'ing the SU700 to a non‑MIDI audio source.

In a similar way to mixers with scene automation, the SU700 allows eight Scenes per Song to be set up. Scenes are snapshots of the status of every SU700 parameter, for instant recall by the eight Scene buttons. These also double as Marker buttons, for setting and recalling Song locations to jump to. Scenes can be used within sequences or triggered live, and are really useful because they store everything, including detailed effects choices and settings, the changing of which can't otherwise be recorded. They also divide potentially complicated mixes into easy‑to‑manage chunks. The user simply mutes unwanted tracks, sets levels, pan position and so on, and saves the lot as a Scene. Pop the sequencer into record, recall the Scenes at the right places, and voila. The only thing to keep in mind is that changing effect types takes time, with effects falling silent for a fraction of a second. Still, a little planning, and rehearsing of Scene changes, should reveal any transition problems caused by effect selection.

This is not the kind of sequencer that makes you enter such things as how many measures a sequence will contain, or a time signature, before starting. It simply records, for as long as you need it to. In fact, a Loop track automatically plays for the entire length of a song (999 measures) if required. There is a limitation, though, in that the sequencer can store a maximum of 32,000 events for all 20 Songs.

No pattern‑based sequencing options are provided, although sections of a Song can be copied to locations elsewhere in the same Song. Extra measures can be inserted — and the new measures can have time signatures of 1/4, 2/4, 3/4 or 4/4 . Because the sequencer always assumes a new Song will be in 4/4, the only way to define a time signature of, say, 3/4, would be to use 'insert measure' mode from the word go and insert 3/4 bars to the required Song length. With care it would be possible to create a song template offering compound time signatures, such as 7/4 or 5/4. Measures can, of course, be deleted as well as inserted.

A simpler variant on the microscope editor found on many hardware sequencers allows the SU700 user to scroll through note‑on events, move and/or delete them, and alter their velocity and length. Knob tweaks can't be edited, but other non‑note events can: Mute, Loop Restart, Roll and Scene events can all be erased, but not moved or otherwise changed. Knob tweaks can be erased from an entire track, if desired, or even copied to another track. There's an 'Undo/Redo' function during sequencing.

Summing Up

The SU700 is fast and fun to use, and it's great to see the kind of flexibility that has for so long been available only in computer‑based digital audio systems appearing in this unit. Audio can be rearranged and tracks remixed almost as easily with the SU700 as on a computer — some would say more easily. Features like the Groove parameters add to the computer‑sequencing feel, and the weird effects remind one of what can be done with some of the software plug‑ins around at the moment. The real‑time DSP, in particular, is stunning. It's only a shame that the SU700 doesn't have a built‑in synth (which another, more expensive competitor, Ensoniq's ASRX sampling workstation — reviewed SOS September 1997 and December 1998 — does), as this would really make it a self‑contained system for more musicians.

The SU700 has so many strong points and excellent features, as mentioned in the main text and the pros and cons box, that it would be mere repetition to list them all again here. There are a few shortcomings, but the positives far outweigh the negatives, in terms of numbers and seriousness. We had a great time using it and were very excited by the possibilities it offers for creative remixing.