Roland UA100

If you want to get started with audio recording on your computer, but don't fancy opening up your PC to install an internal soundcard, the new USB Audio Canvas from Roland subsidiary Edirol may provide a welcome alternative. John Walden takes the UA100 for a test drive.

Hot on the heels of Roland's latest Sound Canvas, the SC8850 (SOS October '99), comes something slightly different under the 'Canvas' banner. The UA100 Audio Canvas concentrates on getting audio signals in and out of your computer, while also providing some effective DSP and a 2‑in/2‑out MIDI interface. Most notably, though, it does all this using the Universal Serial bus (USB) interface.

Music technology companies are now beginning to take the plunge with USB. In theory, this allows easy access to extra audio functionality for the benefit of less confident computer users — a simple cable connects the peripheral to the computer, and items can be 'hot‑plugged' without the need to power down. But how does the USB Audio Canvas shape up and, in particular, how does it compare with the wide range of PCI‑based audio soundcards that are currently competing for a market share?

What's In The Box?

The Mixer mode screen display.

The UA100 offers two‑channel (ie. one stereo pair) recording and four‑channel (two stereo pairs) playback, though there is only a single stereo output, to which playback channels must be mixed down inside the unit. The A‑D and D‑A conversion are both 20‑bit linear, though the wide variety of effects operate using internal 24‑bit DSP, and the sample rate can be set to 44, 22 or 11kHz. The manual states that the frequency response is 22Hz to 21kHz and that the output signal‑to‑noise ratio is less than –92dBm: while these specifications would be adequate for users still happy with 16‑bit audio recording, those seeking the extra transparency afforded by higher bit depths and sampling rates will obviously need to look elsewhere. Up to four UA100s can be daisy‑chained from a single USB port, but the 12Mbits‑per‑second USB bandwidth can only support a maximum of four stereo pairs in any combination of input and output.

The UA100 hardware is housed in a 220 x 250 x 46mm metal case with a clearly labelled plastic front panel, and weighs just over 1kg. Included with the unit are a printed 'Startup Manual', a wall‑wart power adaptor, and the two‑metre USB cable for linking the UA100 to your computer. A CD‑ROM is also included, containing the necessary PC drivers and control software, documentation in HTML format, Cakewalk Studioware control‑panels, example Cubase files, and a software 'virtual' SC88 Sound Canvas module.

A quick chat with Edirol's very helpful technical support department suggested that PC ASIO drivers for the UA100 should be available by the time you read this, and driver support for BeOS has also been promised, though Mac drivers and software are apparently on hold pending evaluation of the USB audio support in MacOS 9.

On the left of the front panel are two quarter‑inch mono jack inputs — 'Mic 1' and 'Mic 2' — followed by knobs for setting the their respective input gains relative to a nominal input level of ‑40dBm. No phantom powering is available, though the 'Mic 1' input can be switched to a 'Guitar' input (nominal input level of –23dBm) by pushing the left‑hand input gain pot. A small LED above the input jacks lights green when a signal is present and red if the input level is too hot.

Two dual‑concentric Effect Control pots can be used to quickly tweak four effects parameters from the front panel, their default parameter assignments differing depending on the setting of the Effect Type knob. The latter can be set to one of six positions: PC (to allow full control of the UA100 via software), VT (Vocal Transform), Vocal, Guitar, Game and Bypass. To the right of the front panel is the largest knob, which sets the output volume, with a five‑stage LED meter above it. A headphone mini‑jack and push‑button power switch complete the front‑panel layout.

On the far left of the rear panel is a connector for the external power supply. Line inputs and outputs, operating at ‑10dBm, are provided on RCA phono sockets, alongside a tiny knob which sets the line input's gain. An S/PDIF optical digital output is provided, though no cable is included with the UA100, and the remainder of the rear panel is taken up by four independent MIDI sockets (two Ins, two Outs) and, of course, the all‑important USB socket.

Setting Up

Some example effects windows accessible when in Compact Effects mode.

As this was my first encounter with a piece of USB music kit, I was intrigued to see how 'plug‑and‑play' the installation process would be. True to Roland's promise, the connection and installation instructions were very clear, and only a few minutes after plugging, I was ready to start playing. The UA100's various inputs and outputs appeared alongside my other multimedia devices in my System settings. Having selected the UA100 as my default device for MIDI and audio, both the Windows Media Player and Cool Edit confirmed that the basic operation of the unit was in order. This done, I then installed the UA100 Controller software, which provides more detailed editing of levels and of the DSP effects than is possible from the front panel.

If you want to get the most out of the UA100 software, the HTML documentation included in the CD‑ROM is essential reading. The provision of hyperlinks between topics is very useful, but there are some sections of this technical documentation that are, quite frankly, poorly explained. How often do people have to say this sort of thing about the documentation supplied with hi‑tech music equipment before the message gets through?

Software Control

The VT Mixer mode screen display.

With the Effect Type switch on the front panel set to PC, the UA100 Controller software offers two main modes of operation: Mixer and VT Mixer. The former mode sets the UA100 to operate as a digital mixer offering a number of different configurations, whereas the latter uses the available DSP to provide a variety of voice‑transformation effects.

In Mixer mode, the left‑hand side of the functional display is dominated by the four input channels. The input source for channels 1 and 2 can be toggled between three settings using the button situated at the top of the channel strips — 'Mic 1/Guitar', 'Mic 2', 'Mic 1/Guitar + Mic 2' and Line. The two latter options cause the individual channel controls to merge into a single stereo channel strip. When either of the first two settings is chosen, the signal at the Line inputs is passed straight through to the Line outputs without any processing. This is useful for combining the output of an external MIDI module with your audio so that a complete mix can be sent to your monitoring system from the outputs of the UA100 without need for an additional mixer.

Channels 3 and 4 represent the two stereo audio pairs being sent from the computer to the UA100 via the USB connection, and are seen in Windows as 'UA100 Wave 1' and 'UA100 Wave 2' respectively. These two stereo channels are eventually combined and passed to the Line outputs, though they can be processed separately while still within the digital domain of the UA100. An additional fader in each channel strip allows the user to feed to a 'Sub' buss in addition to the main mixer buss. Thus, for example, you could monitor your full mix while recording only the effects. These secondary faders can be hidden if the Sub buss is not needed.

Controls at the top right of the Mixer mode display allow configuration of the DSP effects (for a full listing, see the 'Effects Palette' box below) and here, again, two modes of operation are available. In Full Effects mode all the DSP power is dedicated to a single effects algorithm, which can either be inserted into an input channel or be fed from a mixer send (a 'system effect'). The effects return level, where applicable, is tweakable from the centre of the display area. The High Quality Reverb algorithm is only available in this mode. In Compact Effects mode, the DSP power is shared between three algorithms. Two system effects are available (a choice from reverb, delay or chorus), and the third effect can be used as an insertion into any single input channel. Finally, a central column of buttons provide access to some useful preset mixer configurations, while at the bottom right are master faders for setting Output and Record levels.

In VT Mixer mode, the DSP power is used to produce two pitch‑shifted voices from any one selected input channel. Controls for the amount of pitch shift (up to one octave either way), the amount of formant shift, the pan and the level are available for each voice. The three voices can then be further processed through a multi‑effects chain including chorus, delay and reverb. The VT Mixer can be used while other material is playing back through the UA100, and would therefore be useful if you wished to record a processed vocal track against an existing backing track. Clicking on the Manual button for each of the Vocal channels allows the harmoniser's pitch to be controlled via MIDI, changing the display accordingly. However, though this opens up the creative possibilities considerably, there is precious little about this mode of operation in the documentation.

Putting It All Together

Front‑panel Mic and Guitar inputs on the front panel of the UA100 are augmented by line‑level I/O, S/PDIF optical output, and two pairs of MIDI I/O at the rear of the unit.

This innocuous‑looking little box certainly offers a lot of functionality. Testing out its feature set using both Logic and Cakewalk proved painless enough, both sequencers seeing the audio and MIDI ports of the UA100 as standard Windows multimedia devices. For example, in my version 4.04 Logic Audio Platinum simultaneous MIDI and audio happily played back in sync once I'd made the usual adjustments for latency (see the 'ASIO Update' box, right, for more on this point). Moreover, because signals fed to the inputs of the UA100 are sent directly to its outputs as well as to the computer, there's no monitoring‑latency problem while recording and overdubbing. I was able to record reliably in stereo even when playing back a fairly busy mix involving about a dozen MIDI tracks and a similar number of audio tracks.

To my ears, the audio quality is quite acceptable, with no obvious noise problems — I checked the background noise levels and can confirm the –92dBm signal‑to‑noise ratio quoted in the manual. In use, the effects in Mixer mode are both useable and very editable. The delays, chorus and flange‑type effects are up to the usual Roland standard. While the High Quality Reverb is not going to compete with a dedicated reverb unit, it is as good as many of the plug‑in reverbs supplied with MIDI + Audio sequencers. In Compact Effects Mode, the extra flexibility of signal routing does reduce the functionality of some of the insertion effects, but the differences in effect quality are not huge.

If the VT Mixer mode is used just to give a little spread to a vocal, the end result is quite effective; a harmony pitch‑shifted down an octave can give an instant Barry White accompaniment which would be familiar to users of the Digitech Vocalist range. Again, the results will probably not replace a dedicated pitch‑shifter, but if the VT Mixer is used carefully and placed at a sensible level within a mix it can produce some reasonably convincing backing vocals.

Conclusions

The UA100 does exactly what is says on the box, and does it with a minimum of fuss. So who should buy one? This, I think, is where the crunch comes. There are a lot of PCI cards on the market at present at a similar price to the UA100. The Guillemot ISIS soundcard, reviewed in SOS June '99, is a little easier on the wallet, and you get an 8‑in/4‑out card with a basic GM synth/sampler plus a bundle of very respectable software. For a little more than the UA100, you might consider the Terratec EWS88MT (reviewed in SOS October '99), an 8‑in/8‑out card that can work with 24‑bit audio. These and a number of other cards each offer a different balance of functionality and price, but the UA100 does offer at least one potential advantage. If you want to make some initial moves into audio recording on your PC, but really don't want to go through opening up your machine to install a PCI‑based soundcard, the UA100 provides a viable alternative.

If you know that stereo‑in/stereo‑out at 20‑bit resolution is all you are going to need, it provides a very neat, all‑in‑one solution with some effective DSP: for anyone who works almost exclusively with MIDI and samples, but just wishes to add the occasional 'live' performance, the Audio Canvas might just be an ideal desktop solution. However, though I roundly applaud Roland for trying to make the addition of good‑quality audio recording to a PC as simple as adding a printer, at this price point the Audio Canvas faces some pretty fierce competition.