McDSP: Moo X Mixer APB-16 Plug-In

Colin McDowell of McDSP, and his gang of wickedly smart development minions, haven't been sitting back and complacently idling away since releasing the plug-in controlled, all analog APB-16 [Tape Op #134]. The company has recently announced their all-new APB-8 (half the analog processing of the original at nearly half the cost), as well as expanding their current AAX support for the APB series to include VST and AU compatibility: Cubase and Logic Pro X for now, with additional hosts to follow. In case you missed the original review, the APB-8 and APB-16 provide 8 and 16 channels, respectively, of analog dynamics and saturation processing that are handled in the single rack space unit and controlled via a plug-in interface for each of the included processors. This processing, along with 32-bit AD/DA conversion, is handled sample-accurately via a single Thunderbolt cable.

Certainly, the most anticipated update to the APB platform thus far is the release of the Moo X Mixer plug-in. It's actually comprised of two plug-ins: The Moo X Channel, a hybrid analog/digital channel strip with dynamics, EQ and saturation, and the Moo X Master Mixer that can control all of the individual channel instances, finished off by the addition of a stereo bus compressor at the end of the chain. Have more channels that you want to bring into the Moo X Mixer, or want to use the other APB dynamics plug-ins and analog processing once you've filled the mixer up? Up to five APB units can be chained in series via Thunderbolt for additional processing power!

Starting with the Channel plug-in (which can operate independently on any mono or stereo track, or can be assigned to and thereby controlled by one of the 16 channels in the Moo X MasterMixer instance – more on this later!), there is a two-band shelving EQ with an LF range of 40 to 160 Hz and a HF of 4 kHz to 16 kHz. Both bands have 12 dB of gain, and this runs natively on your computer. After this stage, the signal passes to the APB hardware, then through the saturation and compressor circuit. Saturation control is a one-knob affair that can be switched between pre- or post-compression. I find this feature to be one of the most powerful aspects of the whole Moo X ecosystem – not just because I'm a distortion junky. It can range from adding an almost imperceptible amount of hair/warmth/edge (choose your favorite word for saturation) to a thick and gooey, buzzing distortion. The beauty of the saturation circuit is that it never gets bright, thin, or shrill – even at extreme values there's something very pleasing and musical about it. I found that using it in conjunction with the compressor was the perfect way to push a vocal through a dense mix.

The compressor is also a treat to use with only two controls; one knob for a combined Amount/Threshold (along with auto makeup gain), and then a second knob for adjusting the time constant with faster attacks/releases in the counter-clockwise direction, getting slower as the knob travels to the right. Like the Saturation control, this compressor can easily go from a transparent feeling to stun, and at no time does it ever sound bad in any way. I've been putting an instance of the Moo X on my main buses in Pro Tools (drums, bass, guitars, vocals, etc.), and am finding that just a touch of the compression on these buses solidifies everything in a mix while not being too heavy-handed. Also, as I mentioned above, on vocal tracks (both solo and groups), pushing the compressor harder produces incredible presence and vocal intelligibility. The more utilitarian side of the compressor's plug-in GUI contains a VU meter that indicates output level but is also a gain reduction meter when clicked. Additional controls include polarity reverse, Solo, and Mute – the latter two operate in conjunction with the individual channels that are assigned to the Moo X Master Mixer (say that ten times fast!). The input channels can also be named, and this will then appear in a "scribble strip" in the Moo X Mixer Master; the feature was borne out of multiple APB-user requests and is lovely to see McDSP listening to those in the trenches using the gear! Finally, there's an Output attenuation knob at the end of the processing chain.

The second Moo X Mixer plug-in is revealed when creating a Moo X Channel stereo instance of the plug-in on your master output channel or an aux return. Choosing a channel assignment of Master turns the Moo X Channel into the Moo X Master Mixer. The Master plug-in UI offers a large, 8-channel strip and master section display where all parameters from each individual channel instance become visible in one place. There's also a toggle switch that banks to channels 9-16 if you have enough processing resources on an APB-16. This is where plug-in control and analog hardware interaction truly starts to feel like a proper summing mixer by grouping all the parameters available into one place. Audio signals are still routed by the DAW, but the Moo X Mixer controls all the processing on the assigned Moo X Channels while also offering a stereo master bus compressor and custom saturation circuit for the track where it's inserted.The additional features of the Master section include a Solo volume, a Master output knob, and a Master compressor (analog, again!) with expanded dynamics controls: Threshold, Attack, Release, and makeup Gain. Clicking on the Master's output VU meter switches the left meter to gain reduction mode and leaves the right in output mode – handy!

The Moo X Mixer and an APB-16 is worth the price of admission. How many super high-quality mono or stereo analog compressors can you get for $7000? Factor in an incredible sounding summing mixer with tasty EQ and compression on every channel, plus access to all the other APB plug-ins. Do the math and you'll start to see what a true bargain this system is. Do I have any complaints? There are still some growing pains with regards to sample rates higher than 48 kHz (the rare, but occasional "Bandwidth Error" that appears in the APB Status app and requires the unit to be power cycled to come back online), but these are still the early days with this revolutionary platform. Colin is an insanely smart guy, so I can only guess that everything will continue to improve with future software and firmware updates.

I love mixing in the box for the speed and convenience of recall, but I also love analog processing. Having the best of both worlds together with complete, instant recall, plus the true flavor of genuine hardware processing is almost too much to believe. Welcome to the future!