Fig. 1: The SP-404SX has a darker faceplate than the original SP-404. It also gains one new button (the tiny FUNC), which combines with other buttons to activate more than a dozen functions. Two of the effects buttons have switched places as well.

On the Case
The SP-404SX ($499 list) looks almost identical to the older 404 (see Fig. 1). It’s a chunky box the size of a hardback Harry Potter novel—about 7 x 10 x 3 inches. The instrument weighs 2 lbs., 11 oz., without the six AA batteries that can power it 4 to 5 hours. You also get a line-lump AC adapter with a generous 12-foot cord, a CD with sample-transfer software for Mac and Windows, and a 1GB SD memory card.

The bundled SD card is a nice touch; the original 404 used optional Compact Flash cards that maxed out at 1GB. Another nice touch: The software can convert your old SP-404 samples from Roland’s compressed RDAC format to the standard 16-bit WAVs the SP-404SX uses. I thought RDAC sounded fine, but samples sure load faster on the SX. In fact, the SX doesn’t have internal memory banks; it streams all sounds off the card.

Booting up with an 80MB set took just 7 seconds. You can store 12 sets to the card, but loading those backups takes longer. (My 80MB set took 90 seconds.) Because SD cards are so cheap, another approach—if you're careful—is to swap cards when you want a new set. Once the power is on, there will be zero load time, which is a fantastic advantage for live performance. Just don't swap cards while the SP-404SX is accessing them, as that may destroy your data. To be safe, the manual says you should power down before swapping cards, but I didn't have any problems.

With the exception of the card slot, the I/O hasn’t changed (see Fig. 2). I would have liked a dedicated knob for headphone volume; the master volume knob controls both the line output and the headphone jack.

Fig. 2: On the SP-404SX back panel (top photo) you’ll find a grounding screw, a 9V input, MIDI In, RCA line-level I/O, and a Kensington security slot. The front (bottom photo) adds a 1/8-inch headphone out, an SD card slot, and a 1/8-inch unbalanced mic input with trim knob. There’s a built-in mic on the top.

What Would Pad Say
The bottom half of the instrument features 12 sample pads, plus an additional Sub Pad that retriggers the last sound for rapid drumming effects (see Fig. 3). Polyphony is 12 voices (6 stereo samples or 12 mono).

None of these pads is Velocity sensitive, although they do respond to Velocity over MIDI. Roland Product Manager Vince LaDuca explains that most 404 users want consistent levels each time they hit a pad because they’re triggering sound bites and longer clips (think of backing tracks or theater ambiences). Fair enough, but it would be nice to have the option for expression. The upscale SP-555 does have Velocity-sensitive pads, as well as a button that makes all pads respond with full volume. In addition, the 404SX pads felt a bit wiggly; I occasionally experienced double-triggers or non-triggers.

Fig. 3: The SP-404SX offers 10 banks of 12 sample pads. Each pad can be set to loop, play through, or play while held, in forward or reverse. The Ext Source pad unmutes the audio inputs, and the tiny mic button unmutes the internal mic and mic jack.

Five buttons above the pads select banks of samples (or in sequencer mode, drum patterns). Double-clicking them accesses a second bank. That means you can have up to 120 samples and 120 patterns loaded. You can then save those bank sets to 12 files on the SD card, for a total of 1,440 samples per card. Thanks to the SP-404SX’s rapid loading and 32GB capacity, that’s a mass of sonic material at your fingertips.

Hold the Func button, and the sample pads perform helpful functions like loading and saving backups, setting the recording trigger level, and copying samples and patterns between pads. This is a giant improvement over the 404, which offered some of those features, but in a completely unlabeled way. To access MIDI sync, for example, you had to turn on the power while holding the Time/BPM button. Copying between pads wasn’t supported at all. There are still plenty of hidden functions in the SP-404SX; Table 1 lists several I often had to look up.

Sampling on the SP-404SX is fairly easy; the pads flash to guide you, and the display brightness indicates the incoming level. Trimming and looping samples remains fiddly due to the lack of a waveform display. The SP-404SX does offer time-stretching, but as on the 404, the only way to keep two loops in sync is to continually retrigger them from the pattern sequencer. The time-stretching is passable on sparse rhythmic material, but I found even 1 bpm shifts sounded gargly with pitched material.

Hands-on Effects
At the top of the front panel are four rubberized knobs that feel solid and turn smoothly (see Fig 4). The first knob controls volume. In performance mode, the remaining three knobs control effects parameters such as reverb time/tone/depth and filter frequency/resonance/distortion.

Fig. 4: Six effect selectors surround the display; the MFX button calls up 24 other types, listed at right. You can choose one effect at a time and apply it to individual pads (including the external input pad) or to all pads at once.

The SP-404SX’s effects chip is new, and I do think the effects, particularly reverb, sound smoother. Another advance is that you can switch immediately among effects without glitching. As on the 404, you can also gate effects by tapping the effects button while holding the Tap Tempo button.

You get the same 29 effects as on the 404, each with three adjustable parameters, but the effects are organized differently. The cool Voice Transformer and DJFX Looper move to the one-click buttons around the display, sending the 404’s Pitch and Vinyl Simulator effects into the MFX pool—a good choice (see Fig 5). Voice Transformer, which alters the character of a sound by transposing the formants (characteristic frequencies), isn’t just for making cartoon voices; it’s also great for grunging up drum loops. DJFX Looper lets you perform vinyl-scratching effects with one knob, grab slices of sound with the second, and transform the slices from stutters into buzzes with the third. You can resample your knob-twisting performance onto a new sample pad, building up crazy textures.

Fig. 5: Roland’s Wave Converter software doesn’t actually convert WAV and AIFF files, because the SP-404SX uses that format natively. Rather, it organizes them for you on the SD card so they load automatically when you return the card to the SP-404SX. You can also drop a bunch of WAVs in a folder and import them to successive pads with one click.