This Roland product is a rather enigmatic device in that it is difficult to precisely describe its function. Rather than being a blatant effects unit, it falls more into the category of psychoacoustic processors such as the Aphex Aural Exciter, although the two devices are not directly comparable.

The function of this device is to either synthesise a stereo image from a mono source, or to further enhance a stereo sound source, and it may be effectively used on single instruments or complete mixes.

Functions

The Dimension D is basically a two channel time manipulation unit and uses charge coupled 'bucket brigade' delay lines in order to produce the necessary time shift.

The delay time is too short to be perceived consciously, but by modulating the delay time, a pitch change is produced in much the same way as on a conventional chorus pedal.

In the Dimension D, the pitch change is relatively shallow in order to reduce the pitch wavering effect which can be easily recognised when listening to a conventional chorus unit and the direction of sweep is opposite on both channels, producing a sense of movement rather than pitch change. On contacting Roland UK for further information concerning the inner workings, very little extra detail was forthcoming other than the suggestion that some out of phase input signal is fed to the opposite side of the stereo field in order to synthetically widen the perceived stereo images.

Controls

There are no user adjustable parameters and only four preset modes are available being selectable by means of four latching pushbutton switches on the front panel. There is no level matching control and so the input amplitude must be adjusted externally, but the output level may be monitored by means of the ten segment LED panel meter which is operative when an effect is selected.

In addition to the four mode selectors, there is an 'effect off' button which disables the effect but without changing the signal level or introducing any clicks. A further bypass switch is fitted which effectively takes all the electronics out of circuit and connects the inputs directly to the outputs.

A jack socket is provided so that a foot-switch may be used to activate the effect and a red LED is fitted just above the socket to indicate effect in/out status. A pushbutton mains switch and LED status indicator completes the complement of front panel controls, and the rear panel contains the input and output sockets (both jack and XLR), as well as the mono-stereo switch.

In mono mode, the same input signal is fed into both channels whilst in stereo, both channels are largely independent in order to retain their spatial integrity.

Appraisal

Effects settings one to four appear to control the intensity of the effect although all settings are much more subtle than a standard chorus device.

Setting one gives the least dramatic effect whilst setting four is noticeably more pronounced, and all four are effective in mono or stereo modes of operation.

I tried guitar, guitar-synth, bass guitar and various keyboards through the processor and the results were pleasing for all instruments. The actual effect can best be described as a subtle chorus with a definite increase in 'upfrontness' and image width, without any of that 'wow' and 'flutter' effect associated with conventional chorus-only effects.

Background noise was noticeably absent and I assume that some form of internal noise reduction and/or signal pre-and de-emphasis is used to achieve this quality of performance. The effect bandwidth is also high enough not to remove the 'sparkle' from any sound source that I used, indeed the effect seems to add presence in the upper registers.

Because of the nature of psychoacoustic enhancement techniques, the Dimension D needs to be tried out in a real life situation in order to be fully appreciated. The sound quality and low background noise make this device suitable for discerning professional use and this is reflected in its price, which is about twice that of a stereo chorus unit.

Boxing Smart

Roland have opted for a 2U rack box finished in black silk paintwork which matches the rest of their 'rack' range, right down to the chunky little handles.

Both internal and external finish is up to the standard that we have come to expect from Roland and all the controls and connectors are sensibly positioned except for the mono-stereo switch which has been located on the back panel. This means that when the unit is installed in a permanent rack system, you have to employ a contortionist to flip the switch for you!

Final Reckoning

Although difficult to review due to the vague nature of its workings, the Dimension D is a very easy box to live with and would make a valuable addition to any professional or semi-professional studio.

The home studio enthusiast could be sorely tempted by this machine, although I suspect that the relatively high cost might put some people off, after all, you can buy a very respectable digital delay unit for this amount of money.

The Dimension D retails at £355 including VAT, but good deals can be had by shopping around.

Any problems contact Roland (UK) Ltd, (Contact Details).