Roland 7000-series

The V‑Mixing system as supplied for review: in front are the VMC7200 console and MB24 meterbridge, with the VM7200 processor unit in the background.

Roland's entry into the market for mid‑priced digital mixers introduces some interesting innovations, including the separation of the control surface from the inputs and processing rack. Hugh Robjohns puts it to the test.

The 7000‑series, flagship of Roland's V‑Mixer range, has been awaited for some time, and elements of its technology have already appeared in the VS1680 workstation and the VM3100 digital mixer (reviewed in SOS June '98 and July '99 respectively). The series consists of a family of products, with two DSP processor units and two motorised‑fader control surfaces available, plus an assortment of optional interface cards, a meterbridge and console woodwork which enables a wide range of configurations. Probably the most significant difference between this digital console and its peers is the physical separation of control surface and processor rack, using an AES‑EBU interface as the link.

The DSP processors, the VM7100 and VM7200, form the core of the digital console, and provide either 10 or 20 analogue inputs respectively (a further pair of analogue inputs is available via the console), with a corresponding 12 or 22 analogue outputs. Digital I/O is provided by a stereo S/PDIF or AES‑EBU interface (only one can be used at a time); with an optional digital I/O expansion card fitted, a further 24 digital inputs and outputs become available via Roland's 24‑bit R‑Bus (RMDB2) interface, taking the total number of inputs to 48 (38 for the VM7100). The processor provides three internal stereo effects (two freely allocated, and one dedicated to the master/monitor mix buses) but up to three optional digital effects cards can be installed, increasing this to a total of nine onboard stereo effects processors.

The two control consoles are virtually identical, differing only in size, and in the number and length of physical faders. The smaller VMC7100 console has 13 faders (12 inputs plus master), whereas the VMC7200 has 25 faders (24 inputs plus master). On the larger console, a single level of fader‑banking provides access to the optional 24 digital inputs. In applications where more physical faders would be useful, or where audio control is required from two separate locations, it is possible to connect two VM consoles to the same processor rack: conversely, a pair of processor racks can be linked together with an optional cascade kit, allowing a maximum of 94 inputs to be controlled from a single console. Both console types are able to control this number of inputs directly, although there is considerably more fader‑banking involved with the smaller control surface.

The consoles are constructed as simple rectangular metal boxes with the monochrome backlit LCD mounted in an angled pod. The smaller console can be rackmounted, and both can be fitted with optional wooden side‑cheeks and armrest if required. a separate meterbridge is also available for mounting above the console, or separately in a 19‑inch rack.

For this review, I was sent around £8000 of 7000‑series components, consisting of the VMC7200 control surface along with a VM7200 mixing processor, an MB24 meterbridge, the VMSP72 side‑panel kit, a VM24E R‑Bus Expansion card, three VS8F2 effects boards and three DIF‑AT interfaces. This impressive collection of boxes took quite a while to unpack and assemble, although the instructions were easy to follow, suitable tools were included, and everything worked first time!

VM7200 DSP Processor

The functional core of the V‑Mixing system is the 3U rackmounting mixing processor which acts as DSP engine and patch‑panel rolled into one. Most of the analogue inputs and outputs are on its front panel, and a comprehensive internal routing matrix allows physical inputs to be allocated to any control channel(s). The two processors share identical DSP cores but the less expensive VM7100 has only half the analogue I/O.

The VM7200 processor unit contains most of the V‑Mixing system's I/O and DSP power, and can be separated from the VMC control surface by up to 200m.

One of the key features of the processor is its 'Flexibus' system. In short, this provides 12 independent mix buses that may be used for a variety of applications including effects sends (internal or external), foldback sends, monitor cue feeds, subgrouping buses, and so on. Unlike conventional aux buses, the output from one Flexibus can be rerouted to the mix bus of another, if required.

The routing of signals from analogue and digital inputs through processing channels and on to the outputs can be performed manually, or courtesy of the 'EZ Routing Wizard' as seen on other Roland digital products. a selection of setups for typical recording and mixing applications is provided, and user configurations can also be stored and recalled.

Although the VM7200 processor provides only 20 analogue inputs, there are 24 faders on the VMC7200 console because channels 21‑22 are a stereo digital input (selectable from S/PDIF 'Digital A' or AES‑EBU 'Digital B' on the processor), and channels 23‑24 are analogue inputs from the rear of the console itself. The selected digital input passes through a sample‑rate converter, so external word clock sync is unnecessary. However, the desk can be clocked from either of the digital inputs, a dedicated word clock input, any of the three R‑Bus ports, or the internal crystals (32, 44.1 and 48kHz rates are supported).

The front‑panel input socketry for each of the input channels consists of an XLR and a TRS quarter‑inch socket, both able to accommodate signals between ‑64 and +4dBu. These connectors are effectively wired in parallel — the XLR providing phantom power, switched for individual channels from the console — and so only one of the two input connectors can be used at a time. Channels 1‑6 (and 11‑16 on the VM7200) are also provided with an unbalanced pre‑A‑D‑converter insert point on a second TRS connector. This requires the usual split send/return lead, and operates at a nominal 0dBu signal level.

The right of the front panel carries most of the output connectors. The bottom row contains the AES‑EBU 'Digital B' I/O onX XLRs, the output being derived from assignable analogue output feeds 5 and 6, which can be configured to share any of the desk's output signals. Beside the 'Digital B' connectors, a second pair of XLRs provides the 'VM‑link' that is the interface with the remote console control surface. This interface also uses the AES‑EBU format, and so carries audio in each direction, transmitting analogue inputs 23‑24 from the console and a monitor output return to the console. The latter is available as a pair of headphone feeds, a balanced analogue line output and paralleled S/PDIF digital outputs.

The choice of AES‑EBU for the VM‑link is both a strength and weakness of the 7000‑series system. On the positive side, it allows the processing rack to be placed up to 200 metres away at the side of a stage, or in a machine room, where it can be used conveniently as its own stage box or patchbay. It also allows the fan noise in the processor to be kept away from the monitoring position. Running a pair of AES‑EBU lines between the two units is also trivial compared to the hassle and expense of multi‑channel analogue audio 'snakes' to an all‑in‑one console.

However, the AES‑EBU interface was not intended to pass real‑time control data as well as audio, and there are only a few available data bits in each audio word, so the link operates at a relatively low rate. This means that there is a significantly delayed response to any action as the console instructs the processor rack, which then confirms the action displayed on the screen. For example, it takes about one second for the relevant screen to appear after a button is pressed! Adjusting a control incurs a similar delay and, until you get used to it, results in continually over‑adjusting — you move the control, receive no visual feedback from the screen so move it further, only to discover that it was right the first time and you have now overshot the mark! Just trying to re‑centre a number of pan controls occupied me for several frustrating minutes. Fortunately, the audio path responds rather more quickly than the display, as it only has to contend with half the round‑trip link delay. In its 'Continuous' data transfer mode, the system has been arranged to give priority to control data sent over the VM‑link; there is also a 'Noise‑free' mode which protects the link's audio path, but the result is an even more sluggish response time. Whichever mode I selected, the lag between moving a control and hearing the result was noticeable, and quite off‑putting on occasion.

Returning to the panel facilities, a multicoloured LED adjacent to the VM‑link connectors indicates satisfactory data transmission between the processor and the console. Another useful feature is the provision of a push button to mute, momentarily, all processor outputs — handy for avoiding bangs and splats when plugging inputs. The next row of connectors provides eight 'Assignable' balanced outputs on TRS sockets; these are also available on the third (17‑24) R‑Bus multitrack output socket if the VM24E is installed. a further pair of balanced TRS sockets provide the main stereo analogue outputs in parallel with a pair of XLRs on the rear panel.

That completes the output facilities for the VM7100; the larger VM7200 processor includes a further six XLRs in a third row, along with ten TRS sockets in a fourth row. The six XLRs and eight of the TRS sockets access some of the Flexibus outputs — buses 7‑12 on XLRs with buses 5‑12 on the jack sockets. All are balanced and, like the other balanced analogue outputs, operate at +4dBu. The last pair of TRS sockets provides a dedicated monitoring output.

The VM7200 connects to expansion boxes using Roland's proprietary R‑Bus digital interface, and to the control surface via AES‑EBU.

The rear panel is more sparsely equipped, and is the same for both processors. The IEC mains inlet is mounted directly below a cooling fan, and there are no externally accessible fuses, nor mains voltage selector. a pair of MIDI sockets provides In and Out/Thru functions, the latter also providing data for the external MB24 meterbridge. The main analogue stereo outputs are presented here on a pair of XLRs, and a pair of phono connectors provides a dedicated unbalanced 0dBu recording feed.

The S/PDIF 'Digital A' I/O appears on phono connectors on the rear panel, along with word clock In and Out facilities on BNC connectors. System connectivity is completed with a 25‑pin D‑Sub 'Cascade Port', although this only becomes active when the optional VM24C cascade kit is installed. a removable metal panel above this socket permits installation of the optional VM24E digital I/O expansion kit, which adds three further 25‑pin D‑Sub connectors providing three bidirectional eight‑channel RMDB2 R‑Bus ports.

Eight‑channel 'DIF‑AT' interface units are available to convert between R‑Bus and either ADAT or TDIF protocols for popular modular digital multitrackers, although Roland also manufacture a number of devices which are directly compatible with RMDB2, including an eight‑channel A‑D/D‑A converter, the new VSR880 hard disk recorder and an eight‑channel AES‑EBU interface.

VMC7200 Console

The console is quite large, and with its wooden side cheeks, armrest and meter bridge fitted, has a solidity which goes some way to explaining its expense — there are several decent digital mixers on the market which cost less than this control surface alone! The rear panel carries an IEC mains inlet and associated power switch (no fuses or voltage selector) to the right, with a pair of XLR connectors for the VM‑link to the processor rack. MIDI In and Out/Thru sockets are provided, the latter also catering for the meterbridge connection if it is connected to the console. a five‑metre VM‑link cable is provided.

The VMC7200 control surface is equipped with stereo analogue inputs plus two S/PDIF and one analogue stereo output. Communication with the optional meterbridge is via MIDI.

A SmartMedia slot enables 16Mb memory cards (one is supplied) to store scene, mix automation data and system configurations. To the left of the panel is a TRS socket for a GPI‑standard footpedal or (dual) footswitch, which can be allocated to increment scene memories or activate talkback, for example. The monitoring outputs conveyed from the processor via the VM‑link are presented on four phono sockets as a pair of stereo S/PDIF digital outputs, as well as a conventional stereo pair of analogue line outputs. The former are intended for use with digital monitoring loudspeakers such as Roland's DS90 (see SOS Nov '99). Finally, a pair of TRS sockets provides analogue line/mic inputs for channels 23‑24.

Surface Tension

The control surface is dominated by 25 long‑throw motorised faders, which are quiet in operation but exhibit the familiar 'creeping' characteristic when moving to a new position. The VMC7100 employs only 13 short‑throw motorised faders, but is otherwise very similar. Both consoles share the same arrangement of control buttons and LCD display screen — and this is where I found serious problems with the otherwise impressive 7000‑series system. Roland products have in the past been criticised for poor ergonomics and counter‑intuitive operation, and I found design of this console to be disappointingly weak in these areas. This is a great shame as the mixer is extremely flexible and sounds very good — it is just a struggle to use!

The control surface is effectively divided into six operational areas, but recognising the boundaries between the different sections is not as easy as it should be. The LCD display is the heart of the system and is equipped with a contrast control, six 'soft knobs' and six soft function buttons used to modify parameters selected on the screen. However, Roland have made no attempt to align the selected item's graphics with the corresponding control knobs. For example, one display page shows the faders and pan pots for all 24 input channels in two rows. Within this page, horizontal groups of six faders or pan pots can be selected for adjustment, but the correlation between screen and physical controls is vague. The result is that unless you count the screen and physical controls to locate the correct one, you inevitably adjust the wrong control. This poor user interface is made far worse by the lag between adjusting a control and seeing the corresponding change on screen, since by the time you realise the wrong parameter is being adjusted, everyone else knows too! Familiarity often solves these kinds of problems, but I found only marginal improvement over the time I was using the console. Instead of developing greater speed and confidence I actually had to become more methodical and thoughtful, and I believe this is inherently a slow console to use.

There is no speed‑related 'gearing' to the soft knobs and, by default, a complete rotation alters most parameters over a very small range indeed — adjusting a pan from one end to the other required several revolutions. Simultaneously holding down the Shift button (which is in the bottom right‑hand corner near the dial wheel) provides a much higher gearing so that, for example, a pan control can be rotated end‑to‑end with a single wrist movement. Obviously, however, this involves both hands — and, what's more, the resolution is considerably reduced. In the case of the pan control, it did not appear possible to find the centre position at all — I could get close but never actually reach the mark, and had to release the Shift button before I could attain the true centre. Incidentally, I only discovered this function of the Shift key after a thorough search of the 300‑page manual.

Adjacent to the soft buttons and knobs are a pair of 'Page' buttons to access sub‑screens. These are easy to find — but the Cursor keys, which are central to the navigation and selection of parameters within a screen display, are almost invisible (no‑one I showed the console to managed to find the cursor buttons without help). They are actually arranged to the right of the screen, in an inverted 'T' formation (not the usual, recognisable diamond) and are 'hidden' within a regular array of 14 identical buttons controlling unrelated functions. The use of a slightly lighter shade of grey in the background screen‑printing is intended to highlight the cursor keys, but this is rather inadequate. The buttons all illuminate when active, but are arranged in a regular grid with no extra physical separation between unrelated groups of controls. Consequently, identifying the different functional sections is harder than with any other digital console.

Buttons in this section provide access to disparate functions such as the system's inbuilt spectrum analyser and oscillator, the main stereo/monitor bus effects, the assignable effects processors and fader stereo‑linking. You can also set up synchronisation of the automation functions to an external (MTC) timecode source from this section. a button labelled 'Level Meter' returns the screen to a display of channel levels meters.

The button layout and screenprinting on the VMC control surface can be confusing: the cursor buttons are among the group at the top left of the picture, while the Shift button is at the bottom, centre.A group of analogue‑like controls to the right of the screen provides talkback and monitoring facilities — headphones, line and digital outs each have independent level controls. There are two headphone sockets just above the internal talkback microphone, and an XLR socket provides for an external talkback mic, complete with switchable phantom power. The selected talkback mic can be routed (via channel 24) to the console's spectrum analyser, which can be useful for aligning the PA in live sound applications, for example.

Below the talkback section, a set of numeric buttons allows storing and recall of scene memories and locate points, as well as control of mute groups and activation of user macro functions (typically set up to provide direct access to specific control screens). The transport control section at the base of the panel contains the usual transport buttons — play, record, stop, rewind, wind and zero locate — together with a jog wheel. Three further buttons access the 'Library' functions (200 effects, 50 EQ and 20 delay factory presets), activate the Automix system and provide an Undo/Redo option for the automation.

To the left of the transport section, adjacent to the fader strips, are eight buttons that determine the current functions of the faders, switching them between controlling input channels, multitrack inputs, fader groups, Flexibus masters, Multi‑outs and a second processor unit (if fitted). There are 10 circular buttons, of which six access the Flexibus settings (in two banks), and others provide control of channel level, pan, and preamp gain directly from the faders. Shifted functions here also access Cue level, pan and front/back surround panning. a button curiously labelled 'On Display' freezes the current function of the faders so that they remain controlling the last selected parameter, while the LCD can be changed and the soft knobs used to adjust a different parameter, allowing two parameters to be adjusted simultaneously.

Above the channel faders, a row of 'Ch Edit' buttons provides access to a particular channel's settings on the LCD, and a second row labelled 'Status' indicates conditions such as Mute, Solo, audio (multitrack arming) and Automix status, the actual display being determined by four function buttons to the right. These buttons are also labelled with the alphabet for naming channels on‑screen if required — there is no provision for an external QWERTY keyboard. The status buttons under the screen area also double up as fast access buttons for the various channel functions such as equaliser pages and the like.

The four‑band equaliser sounds very good and is unusually flexible, with a separate high‑pass filter and a switchable low‑frequency section (low‑pass, high‑pass, band‑pass or notch filter). However, the screen graphics make it unclear as to which controls relate to which bands, and further confusion is caused by the high‑pass turnover frequency control being located between the low‑mid and high‑mid EQ sections. Furthermore, the controls are arranged (for control via the soft knobs) in two rows of six, in such a way that it is impossible to adjust, say, the frequency and Q of a mid‑section simultaneously. Notching out a resonance becomes a very tedious and repetitive process of cursoring between rows.

Impressions

It would be fair to say that the 7000‑series V‑Mixer has a lot of good qualities. The processor rack is well‑designed, compact, versatile, highly specified, and expandable. The system also sounds very good: the effects (first heard in the VS1680) are comprehensive, quiet and usable, the equalisation is musical and the dynamics processors work very well (and a planned upgrade will apparently add dynamics on every channel). As a lot of the optional extras become essentials in most applications, however, the complete system is quite expensive in comparison with its peers, but does provide more I/O than most.

The current V‑Mixer offering is probably best suited to the live‑sound sector, which was actually where Roland aimed the main thrust of their UK launch seminar. The novel design brings many advantages to this application, such as the AES‑EBU VM‑link which makes it practical to take a control surface on to the stage during a soundcheck to set up the monitor mix actually at the performer's position. The console can also be easily relocated to various different points around the hall to fine‑tune the front‑of‑house sound, where the inbuilt spectrum analyser will be particularly useful.

In all applications, a very significant advantage of the V‑Mixer is that the channel input gain, internal patching and phantom powering status are all remote controlled and stored as part of the scene snapshots — unlike any other digital console at this budget level — which could prove very appealing to a lot of users.

In general, however, I feel that the potential of this series has been compromised by the poor ergonomics of the control surface. Some of this may be addressable with future software upgrades, such as the poor alignment of the physical controls with the onscreen graphics, the gearing of the soft knobs, and the inconvenient grouping of parameters into pages. Other aspects, however, are more fundamental. Whilst the facilities on offer are in general very good, I found too many of them to be just plain awkward to use. Even turning the system on requires user intervention halfway through the two‑minute boot‑up, and the 300‑page manual hides crucial information in seemingly insignificant 'memos' tucked away on the inside margins!

Considering the number of assignable digital consoles already on the market, most of which use graphical displays and associated 'soft' controls reasonably successfully, I am surprised that Roland didn't arrive at a more user‑friendly solution. To check that my own particular expectations of a digital console were not unduly influencing my findings, I introduced the VM7200 to several other people, all very experienced with a wide range of analogue and digital consoles, to seek their comments. Not one of them was able to find their way around it without guidance, so I feel justified in saying that of all the digital consoles I have used, across all budgetry levels, this has been the hardest to get to grips with. Even when familiar, it remains the most frustrating to use.

The bottom line is that this is a fine‑sounding system, with good onboard effects and processors, which offers a number of unique advantages in a live performance situation. However, I feel that there are a number of significant ergonomic shortcomings which will need to be addressed before it becomes a serious contender in the recording sector of the market.