Meet the Hybrids

Sep 1, 2007 12:00 PM, By Rusty Cutchin

           

Four analog mixers with digital audio interfaces.

FIG. 2: Phonic’s Helix Board 24 FireWire MKII has a list of features as long as its name, including 16 mic pres with direct outs, 108 onboard effects presets, 2 footswitch inputs, and a dedicated subwoofer output with inserts.

Phonic Helix Board 24 FireWire MKII

The Helix Board 24 FireWire MKII ($999.99) is a 16-by-4-by-2-channel mixer with onboard digital effects (see Fig. 2). With 16 mic pres, 16 line inputs, and 16 channel inserts, it offers the most input options of any of the mixers in this roundup. The Helix Board 24 can send 18 independent channels of audio at 24-bit, 96 kHz resolution to your computer with near-zero latency. The mixer's S/PDIF digital output is preset to a 44.1 kHz sampling rate, but you can change it using the included PC-control software or in the Mac's Audio MIDI Setup utility. A 32/40-bit DSP engine powers the board's 16 digital effects, and its 17.5-inch-wide frame is packed to the gills with six aux sends, four subgroups, two footswitch inputs, and an XLR mono/subwoofer output with insert points. You also get Steinberg Cubase LE workstation software.

The Helix has a rotating I/O module (reminiscent of the ones on classic Mackie 1604-series mixers) that you can position for desktop or rack use. The module rotates easily, but the screws used to secure the cover plate after rotating the module are small and difficult to work with. In fact, everything is small on this unit because of its multitude of controls. Even so, most are easy to grasp and operate.

The board's analog features include 3-band EQ with a sweepable midrange-frequency control on all 16 channels. Each channel also has a 75 Hz low-cut switch, its own phantom-power switch, ¼-inch TRS insert jacks, and a direct-out jack. Four knobs set the six aux-send levels. You can set send 1 and 2 collectively to pre or post, and you can switch send 3 and 4 to feed aux outputs 5 and 6.

Aux send 3 doubles as the send to the internal effects section, which includes reverb, chorus, and delay, and a total of 108 presets and 4 test tones. You will not find distortion effects or dynamics processors (besides some gated reverb presets), so you'll want to use guitar processors or outboard compressors when recording guitars and vocals. Also missing are dedicated instrument inputs.

The Helix provides several useful digital options to facilitate recording and playback over FireWire. The most important of these is also the most cumbersome to access: setting the outgoing digital signal from any channel to be post-EQ (and post-low-cut filter), which allows you to record using the board's EQ. To access the switches that enable this option, you must remove a plate on the bottom of the unit. In most cases, you can probably set these once and forget them. But if you want to bypass the EQ section entirely on certain channels before digital conversion, then you'll either have to plan for those channels in advance or perform the same tasks session-by-session: power down the board, turn it over, remove the plate, and set the switches.

You can select which stereo pair will be sent over FireWire as channels 17 through 18: main L/R, group 1/2, or aux 3/4. That's a useful option if you need to record, say, a live drum mix but don't want to take up more than two tracks. You can also assign the stereo mix returning from the computer to the aux 1 output. That way, if you're using aux 1 for a headphone mix, you can send the players a mono mix of the recorded tracks with the push of a button.

At $1,000, this unit is a bargain. Its preamps sound good, its effects are useful, and the included software makes it a versatile, professional-quality recording system (you add the monitors). Although you can't access its EQs and effects individually for mixing from the computer, you can use these processes for recording, and that is extremely handy.

FIG. 3: M-Audio’s NRV10 approaches the flexibility of full 2-way digital mixing by sending its channels to individual tracks of your computer audio application and routing the returns of those tracks back to individual channels of the mixer.

M-Audio NRV10

The NRV10 ($899.95) is a compact mixer with four mono mic/line channels and two stereo channels (5/6 and 7/8). Channel 5/6 includes an XLR connector, allowing five mics to be used simultaneously. A third stereo channel (9/10) is dedicated to a corresponding output from your computer and DAW.

Unlike the larger units covered here, the NRV10 lets you do more with your recorded tracks than just listen to a stereo mix (see Fig. 3). When you assign DAW tracks to NRV10 outputs 1 through 8, those tracks become available on the corresponding NRV10 mixer channels, allowing you to use the mixer's EQ, faders, and effects section. These can, in turn, be recorded back to the DAW as individual tracks or a stereo mix.

Because it is an M-Audio product, the NRV10 works with Pro Tools M-Powered ($299.95) version 7.3 or later, which is a paid upgrade for users who bought versions of Pro Tools M-Powered prior to November 2006. The NRV10 comes with a trial version of the application, along with a utility to manage the mixer's onboard effects section and drivers for both Mac OS X and Windows. You must install drivers on either platform before the NRV10 will be recognized by your computer. M-Audio recommends connecting the unit while it and the computer are powered down.

The NRV10 is an 8-by-2-channel analog mixer with a built-in 10-by-10-channel FireWire 400 audio interface that operates at 24-bit resolution and an up to 96 kHz sampling rate. Its integrated digital effects processor features 16 effects with 16 variations each. These are mostly reverbs with some delay and chorus effects thrown in. You can monitor three different sources over headphones: the main mix, the cue mix (muted channels), or the monitor mix (aux 1). In each case, you get the stereo 9/10 feed (from your recording software's main outputs) mixed in on its own pot.

You can select whether the channel signals assigned to the FireWire bus will be pre- or post-EQ, allowing you to record processed channels to DAW tracks. But you must use this feature carefully: because the computer is sending and receiving to and from the same channels, it's possible to create feedback loops that could damage your system.

You can use the unit's two aux buses to access external processors or create a custom headphone mix. Aux 2 also feeds the internal effects section. That is particularly useful for adding effects during live performance or overdubbing. And M-Audio sweetens the effects pot by including a dedicated version of Audiffex's interFX program, which functions as a digital insert point for each of the mixer's input channels. With this little gem, not only can you add compression and gating to any input, but you can also directly access any two VST plug-ins on your computer from the same channel.

As long as your computer is fast enough that latency is not a problem, the NRV10 provides enormous flexibility for signal processing and basic recording in a performance or rehearsal situation. Its handling of digital signals gives it a great deal of power in an amazingly small box. (For a full review of the NRV10, see the June 2007 issue of EM, available at www.emusician.com.)