M-Audio NRV10

This neat little unit offers great flexibility for both studio and stage work.

Ever since audio interfaces first appeared for computers, I've felt that for many general-purpose studio applications the combination of a mixer (analogue or digital) and an audio interface would make perfect sense. It simpifies routing, gives you monitor control and provides multiple mic preamps when you need them. It also sits you behind a comfortable and familiar control surface.

Over the past couple of years, the hybrid analogue mixer/digital interface has become more popular at the affordable end of the market, with companies such as Alesis and Mackie already established in this growing area. M-Audio are clearly in a good position to join this market, especially since their acquisition by Digidesign's owners Avid, so it comes as no surprise at all to discover that their NRV10 is fully compatible with Digidesign's M-Powered version of Pro Tools (a demo of version 7 comes with the mixer). Fortunately, it also works with all the other popular DAW software, and driver software is included for both Windows and Mac OS, including the new Intel Macs.

Essentials

The NRV10 combines the features of a 10-in, 10-out digital audio interface with those of an 8:2 analogue mixer, all bundled in a compact and affordable desktop package powered via the ubiquitous external PSU. The mixer connects up to Mac or PC machines via standard six-pin Firewire 400, combining the benefits of digital production with the convenience and immediacy of analog control and the subjective sonic benefits of analogue mixing.

Of course, you don't have to use the NRV10 as an interface: it may also be used as a stand-alone analogue mixer. It can be further enhanced by means of the included NRV10 InterFX application software, which enables the mixer to make use of third-party VST effects running on a connected computer. This is certainly an attractive proposition for those users not afraid to take a laptop on stage with them. Using this software, users gain a compressor, expander/gate, and two VST effect slots per mixer channel. The best way to visualise the signal flow is to imagine that the software effects are connected via the hardware mixer channel inserts.

The integral Firewire interface is designed to handle up to 10 channels of audio in both directions, with 24-bit/96kHz resolution. The mic preamps are based on M-Audio's Octane preamp technology, and the layout provides four mono mic/line channels, augmented by one stereo, line-only channel and one channel that can be used as a mono mic or stereo line channel. So, as far as the Firewire interface is concerned, there are six source channels, the last two of which can be stereo, bringing the maximum input count to eight. Phantom power can be switched to the mic inputs (globally) by means of a rear-panel push switch. All the channel strips have gain trims, with mic/line switching on channels 1 to 5/6.

When connected to your computer, the intuitive InterFX software provides all the control you need in one simple screen.Insert points are available on the four dedicated mono channels, and the mic and line inputs are on balanced XLRs and balanced quarter-inch jacks respectively. All six channel strips have identical three-band EQ, operating at 12kHz, 2.5kHz and 80Hz, with centre-detented cut/boost controls (+/-15dB), and there are two aux sends per channel — one pre-fade for monitoring and one post-fade for sending to effects. Both feed output jacks on the top of the panel, but Aux 2 also feeds the internal digital effects processor that makes available 16 variations on each of 16 preset effects types, ranging from reverb and echo to modulation and pitch change. These are selected by means of two 16-position rotary switches and the Aux Return 2 gain pot sets the overall amount of effect added back to the mix. Individual channel effect amounts are set using the Aux 2 control in the usual way.

At the bottom of each channel is the usual pan control and short-throw level fader, with a button below the fader that doubles as a Mute and Cue. The headphone output has its own gain slider and the source can be switched between the monitor mix, main stereo mix and the Cue feed. Essentially, the channel Mute/Cue buttons mute the channel signal from the main mix and feed it instead to the Cue buss, much in the manner of a Solo system. Both Aux sends have corresponding stereo returns, again on jacks. So far, then, the NRV10's layout and feature set is not dissimilar to what you'd expect from other entry-level mixers.

Firing It Up

The Firewire implementation is surprisingly flexible. Each of the six channel strips has a button above it that routes the audio directly from the computer back into the channel strip. Regardless of the switch setting, the channel signals are always available at the computer and the return signal from the computer always passes through the EQ section and bypasses the input trim control. The feed to the computer, however, can be pre- or post-EQ, and when post-EQ, it also comes post-insert point. When the Firewire buttons are down, the separate Firewire returns from the computer are routed back through these same channel strips for mixing; Firewire outs 9/10 are routable to both the Control Room outs and to the phones outs, via a pair of rotary level controls in the main section. When the Firewire button is pressed in, the channel is, in effect, monitoring 'in-line' the source from the computer output as you record and replay material, so there's no need to change gain setting when it comes to mixing. When the button is out, the normal analogue signal path is active, so that you can monitor source signals as you record without hearing any latency. Additional faders handle the main and control room levels. Twin LED level meters follow the main output, which is available on both balanced TRS jacks and rear-panel balanced XLRs, while the control room outputs are only via quarter-inch jacks. While most mixes will comprise more than eight tracks, the ability to feed a basic stereo mix, plus up to eight key parts, back to the mixer for final balancing is a huge step up from only being able to monitor the stereo mix from the computer.

M-Audio make much of the live applications of this mixer, which allow computer tracks to be mixed with live vocal or instrument tracks, all with analogue mixer convenience. The monitoring can be used to send a click track to a drummer and it is also possible to monitor material via the headphones before feeding it through to the PA. As mentioned earlier, if you're happy to connect a laptop to the mixer during live performance, the included software provides you with gating and compression on each channel, as well as two VST insert slots per channel, so if you already have suitable VST plug-ins, this is a practical way to make use of them. The same benefits apply if you are using the mixer for remixing up to eight sources from a separate hardware recorder via the mixer's analogue inputs, as you can, again, use your VST effects and included dynamics, along with the on-board effects, to process your mix.

Operation

Driver installation from the included disc was a very straightforward affair, after which the NRV10 showed up in Logic Express (the DAW software I happen to use on my laptop) as 10 available inputs and outputs. These tests were done on my Intel Macbook Pro and everything went very smoothly. Routing was generally very straightforward from the mixer panel so, assuming you understand the basics of analogue mixers, you should feel at home within minutes. There were some monitoring combinations that could cause feedback (specifically when the channel Firewire button was down, with EQ set to Post). With this setting, the signal from the computer passes through the mixer channels and gets routed directly back again, and this is particularly easy to do if you forget to set the Pre/Post button to Pre EQ when using the InterFX application. The included PDF manual explains how the signal flow should work and warns you of situations best avoided — but if you forget, the ensuing howl of feedback will soon remind you!

The rear panel hosts the inserts and ouputs; two Firewire 400 ports, enabling you to daisy chain with other Firewire devices; and a global phantom-power switch. As with many small mixers, the mic and line inputs are all on the front panel.

The NRV10 InterFX application turned out to be a very useful and straightforward piece of software. When using the mixer for combining analogue sources rather than the feeds from your DAW software, InterFX puts its on-board dynamics processing and up to two VST plug-in effects in each channel insert point. The audio buffer size can be set from within the application, and everything else you need is set out clearly on one page, including gain adjustment pots. The included compressors and expander/gates are very easy to set up (and are always available), and the two VST effects slots can be used to add other effects or processors from your own plug-in library. Unfortunately AU effects aren't supported. This is not a political decision and I'm told the aim is to add AU support at a later date, if practical. Also, because InterFX is a real-time audio application, it can't offer plug-in delay compensation (which, in a DAW, works by streaming data from the source early, to cancel out the delay), but it might have been beneficial if the delays on all channels were made the same, so that when mixing via the application using a hardware multitrack recorder as a source, you could guarantee all tracks would still be in perfect alignment. In other words, if you had a plug-in inserted into one channel, equivalent delays could be inserted into the other channels.

In terms of sound quality, the interface works as well as any properly designed low-cost interface can be expected to, with no discernible background noise or buzz and no obvious coloration. Obviously, it isn't going to be anything esoteric at this price but in the typical project studio it is unlikely to constitute the weak link in the audio chain. The mic amps don't let the side down and I'd be very happy to make serious recordings through the NRV10. The three-band, fixed-frequency EQ was never going to be particularly flexible, but at least it sounds sweet enough when used for general tonal polishing. In any event, you'll probably have VST plug-ins available within your DAW if you need anything more assertive.

Of the on-board effects, more than half are given over to reverb and delay treatments — which is good news, as these are what most people need most of the time. The subjective reverb quality is very believable and the reverbs sit well in a mix, with plenty of sensible options for use with vocals, drums and guitars, as well as the obligatory huge cathedrals and quirky non-linear settings. Again, it isn't esoteric but it is as good as, if not better than, most of the synthetic reverbs bundled with the most popular DAW software, and it won't drain your CPU resources.

The NRV Verdict

While the channel count of the NRV10 isn't going to be up to recording a complete band with a fully-miked drum kit, it does have more than enough capacity to handle a couple of musicians who need to sing and play at the same time — and that should more than meet the needs of most project studio owners. It is straightforward to use, delivers very acceptable audio quality and has the friendly, hands-on feel of a traditional analogue mixer. The EQ is basic, but it works well and it is no more limited than the EQ section of most competing small mixers. The mic amps sound very capable, with no noise issues, and the included NRV10 InterFX application is a useful bonus — I particularly like the fact that you can mix up to 10 audio streams from your DAW, as many competing mixers let you record multiple channels but restrict you to stereo playback, robbing you of the ability to use the mixer for mixing.

You'd be very hard pushed to find a separate mixer and interface that delivers the same performance as the NRV10 for the same total cost, and you'd lose out on the convenience of only needing a single Firewire cable to get up and running. You might also lose out on the built-in effects and you wouldn't have the flexibility offered by the InterFX software. If you have a laptop studio that needs to be mobile, the NRV10 is a near-ideal solution and, even where mobility isn't an issue, it simplifies the setting up of a home studio, while saving the cost of buying a separate audio interface, monitor controller and either a small mixer or a number of dedicated mic preamps. The NRV10 is definitely worth a closer look if you're after a simple setup that combines a decent amount of flexibility with the ability to make great-sounding recordings.