Korg PXR4 4 Track Digital Recorder

With the new ToneWorks PXR4 digital recording studio, Korg seems determined to destroy two popular notions: one, size matters, and two, you can't take

With the new ToneWorks PXR4 digital recording studio, Korg seems determined to destroy two popular notions: one, size matters, and two, you can't take it with you. This diminutive 4-tracker, which records on SmartMedia cards, packs a surprisingly large feature set into a box the size of a personal digital assistant, and it can run on batteries as well as AC power. The Korg PXR4 records as many as four audio tracks and seven virtual tracks beneath each of those, for a total of 32 tracks (4 mixable, 28 virtual). Other Korg PXR4 features include a tuner, 99 locate points per song, 77 modeling effects, 32 metronome patterns, and 55 drum patterns. When you factor all of that in with the unit's editing capabilities, you have to wonder whether the PXR4 is the last stage of miniature recording technology before the implanted microchip.


The Korg PXR4 is only about five inches wide by four inches long, so space, though well used, is tight. Situated along the top rear panel are the USB port, AC adapter input, power switch, and I/O section. The three-position sliding power switch lets you turn the LCD backlight off to reduce power consumption when using batteries, thus prolonging battery life. (With the backlight off, two AA batteries provide as much as ten hours of operation; with the backlight on, you get about two hours.)

The I/O section of the PXR4 consists of a ¼-inch input jack labeled Guitar Input, a stereo miniplug input jack labeled Line Input, and a stereo miniplug line-level output labeled Output. An Input-Select switch lets you pick which input — Mic, Line, or Guitar — is active. Engaging the Mic setting activates a built-in condenser mic that's actually good at capturing sources such as acoustic guitars and even drums. The stereo miniplug input allows the PXR4 to get signals from a keyboard or even a mixing board. Another switch (also labeled Guitar Input) lets you choose between Hi and Lo settings, to accommodate either high- or low-impedance guitar pickups. The PXR4 lacks provisions for MIDI or digital I/O.

Along the bottom front panel of the Korg PXR4 are a stereo miniplug headphone jack; a large, numbered rotary Volume control; and a large, numbered rotary Input Trim control. The SmartMedia card slot is located on the left side of the unit.

The PXR4's top panel is where the action is. The LCD is packed with info — and it's just large enough to allow you to make sense of it all. Track names, levels, effects, time/bars, and editing information are viewable at a glance, and the backlighting comes in handy in low-light situations. Below the LCD are five faders (one per track and one master), each of which does double duty controlling monitor/playback levels as well as parameters of the effects modules. In fact, most of the top-panel buttons serve more than one function, thanks to a Shift key. For example, each track has a dedicated Select button that lets you arm it for recording, and you also use those buttons to select the four effects modules. The button above the Master fader has three functions: Mixer, which lets you control things such as track Level, Pan, and Effects Send; Display, which allows you to set levels and view them prefader or postfader; and Write, which lets you store changes to your effects patch.

The right side of the Korg PXR4's top panel provides a large data wheel, a four-way cursor pad, the built-in condenser microphone, seven control buttons (Effect/Tuner/Assign, Locate/Bounce, System/Rhythm, Mark/Undo, Shift, Exit, and Store Mark), and, along the bottom, the five standard transport-control buttons: Play, Stop, Record, Rewind, and Fast Forward. The transport controls function as you'd expect except for one peculiar feature: the Fast Forward and Rewind buttons double as the selector buttons for songs. In other words, if you're at the zero point and hit Rewind, you jump to the song prior to the one you're working on. To get a standard rewind or fast-forward function, you have to press and hold the button.

Aside from the faders, the primary way to make data changes on the Korg PXR4 is with the cursor pad and data wheel. Because of the space constraints, the PXR4's deep functions are menu driven; navigating the menus is probably the most complicated thing about the unit's operation. The Effect/Tuner/Assign, Mod, and other buttons take you to menu screens where you can modify parameters. From there, a compasslike page guide in the LCD indicates the directions in which you can cursor or whether you've reached the end of the menu. Although the PXR4's manual is well written and describes all the menu pages in detail, it would be helpful if Korg provided a printed map of the menu pages and how they are organized.

The data wheel is a bit more straightforward. In general, the wheel lets you dial in precise numbers for any menu item that's blinking. I found it easier to set track levels and effects settings with the data wheel than with the minifaders.


Using MPEG-1, Audio Layer 2 data compression, the PXR4 records 24-bit audio at 32 kHz resolution. You must select one of three recording modes — Hi Quality, Standard, and Economy — at the beginning of a project. As you'd expect, the higher quality the recording mode, the less recording time you get (see the table “PXR4 Recording Mode Times”).

The Korg PXR4 ships with a single 16 MB SmartMedia card, all of which is taken up by the demo songs. The first order of business, then, was to free up the card by backing up the demo-song data to my Mac's hard drive. That was easily done using the built-in USB interface. Windows ME/2000 or later and Mac OS 9.0.4 or later are supported. After making the physical connection with a cable (not included), I dialed up the USB page on the PXR4 and selected Yes when prompted. A Mac volume called Unnamed popped up on my desktop, and I was in business.

The files created by this procedure are proprietary and, as of this writing, cannot be edited using PC software. If, however, you use the PXR4's Bounce feature to create a mixdown in MP2 format (not to be confused with the more common MP3 format), your computer can play the file — that is, assuming you have an audio card that supports playback at the 32 kHz sampling rate. A 16 MB card gives you only about four minutes per track, including Virtual ones — just enough memory for one song. Fortunately, SmartMedia gets cheaper every day. I'd recommend getting at least a 64 MB card right off the bat. The PXR4 supports cards up to 128 MB.


To test the Korg PXR4, I recorded a mix of acoustic and electric guitars and drums — an approach that required using all three ways of getting sound into the unit (¼-inch guitar jack, stereo miniplug, and built-in condenser mic). I started with a guide track from the unit's built-in rhythm generator. Beat styles range from rock, funk, and disco to jazz and Latin and time signatures from 1/4 to 8/4 and 1/8 to 8/8. Not surprisingly, most of the drum patterns employ a 4/4 time signature. The drum kit is not editable, and the patterns cannot be chained together like a sequence.

The PXR4 offers 77 types of effects arranged into four blocks: Drive/Lmt (Limiter), Cab (Cabinet)/EQ, Mod (Modulation), and Amb (Ambience). These blocks use one of eight combinations of effects called chains, any one of which can be inserted at one of four points: the guitar input, the line (stereo miniplug) input, the master bus (an effects send for the individual tracks), and at the master L/R output. The effects available simultaneously depend on the chain you're using. For instance, none of the Guitar chains include reverb — you have to add that later as an insert or a master effect.

On the whole, the effects were pleasing sonically. I had to crank the reverb returns to get enough level, but the fair selection of reverb patches was highly detailed and not metallic sounding. Tweaking any effect is fairly simple; once you are in Edit mode, the track-select buttons take you directly to parameter pages and the faders become data sliders for adjusting them. When you've dialed in the sound you want, you can save it to one of 100 User Effects locations.

The 4-band EQ block comes in six flavors: Lo, Mid, and Hi, each of which lets you zero in on more specific frequencies; and three Wide settings that allow for broader EQ curves. Each of the six blocks lets you tweak four bands of frequencies in its dedicated range. For example, Lo allows 10 dB of boost or cut at 80, 120, 250, or 550 Hz. Unlike a conventional mixer, the EQ block must be used like an effect, either at the insert point (to EQ while tracking) or across the stereo bus (to EQ while bouncing). The PXR4 also offers a feature usually reserved for high-end standalone recorders and software: time compression and expansion. Although only casually mentioned in the manual, that's a pretty cool and useful effect.


I used my Rickenbacker 360 for the guitar input test. The modeled guitar amps were very usable, though I did have to back off the levels quite a bit before using them — the default settings provide far too much gain. With its level backed off a bit, the Vox AC30 model gave me a nice, chunky rhythm guitar sound. I double tracked the part. The bass guitar had a preset designed for picking, which added some limiting and high-end EQ.

For my two acoustic-guitar tracks, I used the built-in condenser microphone, combined with the Mic'ed Acoustic preset effect, which includes a bit of gentle compression and a Vintage Condenser mic simulator. To position the mic for optimal pickup, I propped the unit up on its left side (the only one with no jacks or knobs), at an angle, so the mic faced the guitar from about a foot and a half away. That gave me a full, balanced sound.

To test the PXR4's line input, I miked a four-piece drum kit (kick, snare, two toms, and two overheads) and bused the six signals down to a stereo pair through a Mackie 1402. Using the PXR4's Vintage Comp compression preset at the input, I generated some pleasingly fat drum sounds.


At this point, I had used seven tracks and not even done the vocal yet. Thanks to the Korg PXR4's Virtual Track and Bounce features, that wasn't a problem. As mentioned previously, each track has seven layers of tracks beneath it, each of which can be recorded, copied, inserted, and bounced at your will. But be careful, because it's easy to eat up a 16 MB card fast. Assuming you don't erase them, you will have all of the prebounced takes for later use, in case you don't like your bounces. The only feature I missed was a track-exchange function for swapping tracks. Rather than exchange tracks, you have to copy them and then delete the old ones. That is a minor complaint, however; no other ministudio I know of lets you edit tracks this freely.

The Bounce feature allows you to mix down four tracks to one or two (stereo) tracks. (By the way, you can also overdub live tracks from the inputs as you bounce with this feature.) I'm a stereo kind of guy, so with my original tracks safely on Virtual tracks, I bounced away in stereo. In the end, I had put all four guitars and the stereo drums on tracks 3 and 4, lead vocal on 1, and bass on 2. For each bounce, I used a bit of the EQ/mastering effects on the stereo bus to keep everything hot and sweet. For the final mix, I used a preset called Final Mix. I also liked one called Tape Sim, which added some gentle limiting and tamed some of the digital edge I'd accumulated. A portion of the song I ended up with is posted at www.emusician.com.


Every songwriter has a story about a great song that slipped away because there was no opportunity to record it — typically, because he or she was out and about somewhere, far from a recorder. In this regard, the Korg PXR4's portability and ease of use — not to mention the vast sonic improvement it makes over hissy, warbly cassette multitrackers — make it a songwriter's dream come true.

The Korg PXR4 stands out for several reasons. It is the only recorder in its class to offer four recordable tracks and a master fader. It's also the only one to let you cut, copy, and paste audio at will. In short, the PXR4 lets you start with an infant idea and grow it into “demohood.” If you don't want to wait for that implanted microchip, check out the PXR4.

Steve Brodersonis a Versailles, Kentucky-based writer and producer. He creates original music for broadcast and teaches an audio-recording course at Asbury College in Wilmore.


portable digital studio


PROS: Clean, natural sound. Straightforward operation. Flexible editing. Great effects. Built-in computer interface.

CONS: Miniplug I/O.


Korg USA, Inc.
tel. (516) 333-9100
e-mail product_support@korgusa.com
Web www.korg.com

PXR4 Specifications

Physical Audio Tracks4Virtual Audio Tracks32Simultaneous Record/Play Channels2/4Preset Rhythm Patterns32 metronome patterns, 55 drum patternsSampling Rate32 kHzA/D/A Converters24-bitInternal Effects Processing24-bitEffects Patches100 preset, 100 userAnalog Inputs(1) ¼" guitar (high- and low-impedance selectable); (1) stereo miniplugAnalog Outputs(1) ¼" stereo miniplugBuilt-In Microphonestereo condenserStorage MediumSmartMedia card (4-128 MB)Maximum Songs99 per cardMaximum Recording Timedependent on card size, recording gradeSupplied AC Adapter4.5V, 500 mABatteries2 AA (not included)Battery Life2 hours (with backlight on)Displaybacklit LCD, 0.217" (W) × 0.099" (H)Dimensions4.625" (W) × 4.125" (L) × 1.125" (D)Weight0.58 lb. (without batteries)

PXR4 Recording Mode Times

With 16 MB SmartMedia Card

Hi Qualityapproximately 11 minutes on 1 trackStandardapproximately 16 minutes on 1 trackEconomyapproximately 33 minutes on 1 track
With 128 MB SmartMedia Card

Hi Qualityapproximately 90 minutes on 1 trackStandardapproximately 135 minutes on 1 trackEconomyapproximately 270 minutes on 1 track