Mix Rescue: Adding Presence

We help transport listeners from a small studio to the Big Easy!

Robin Phillips is a very fine pianist and singer, who is well known on the London jazz scene. His home‑recorded piano skills are currently earning millions of streams for jazz‑house artist Berlioz, while his vocal chops lent some class to our video feature comparing versions of the AKG C414. And late last year, Robin was wrapping up a project that was particularly special to him: his first album of original songs for over 20 years. This latest endeavour features not only regular bandmates from a number of his current line‑ups, but also London’s Soul Sanctuary gospel choir, big‑name jazz players from both sides of the Atlantic, and a string quartet. The first single from the album is ‘Ode To NOLA’, his homage to New Orleans.

Robin normally mixes and masters everything himself, but this particular track wasn’t cooperating. Given its importance as the lead‑off single from the album, he called me to ask for some advice. One thing led to another, and soon I had a very neat and well‑organised multitrack to download!

Close Calls

Visits to historic studios such as Sun Studios and Muscle Shoals Sound Studios had convinced Robin that recording musicians in a room together was key to getting the vibe he wanted. To this end, he has made use of recording spaces including London’s MasterChord Studio and New Orleans’ Marigny Studio. ‘Ode To NOLA’, however, along with many other songs on the album, was tracked in his own home studio. This is a very well‑equipped affair, with lots of tasty mics and outboard feeding a Focusrite Red 8Pre interface, but the live room and control room are both pretty compact. Not a problem for recording solo instruments, but enough to introduce some challenges when you want to capture a band live including a full drum kit.

When you’re tracking live in the same room, drum spill onto the vocal mic is inevitable!

For the initial live session, Robin had sensibly banished bassist Louis Thorne to the control room in search of a spill‑free upright bass recording, while he himself sang and played Rhodes piano in the live room, with drummer Claire Brock on a full drum kit very close by. Electric guitarist Neil Cowlan and Pinstripe Suit brass players Stacey Dawson (sax) and Sam Sankey (trombone) added their parts later in the same studio, and the whole thing was topped off with a Hammond overdub by Robin courtesy of his Nord Electro 5D, amped through a Vox AC30 and captured by Coles 4038 and Shure SM57 mics.

Louis Thorne’s upright bass was tracked in the control room, using an AEA R84A ribbon mic.When we spoke, Robin identified a couple of things that were proving troublesome at the mix, and perhaps contributing to a sense that the track as a whole was lacking in presence. Both the Rhodes and the electric guitar had been recorded through wah pedals, and whilst both sounds were very cool in isolation, they were treading on each other’s toes. The upright bass sound was impressive on its own, but its powerful low end was proving hard to handle in context. Finally, Robin’s live vocal mic had inevitably picked up a lot of drum spill. The Electro‑Voice RE20 suited his voice very well, and has cleaner off‑axis sound than most dynamic mics, but because the spill was being bounced around in a small space before arriving off‑axis on the mic, it didn’t sound great. Pushing up the vocal fader thus compromised the otherwise well‑recorded drum sound, and adding compression or high‑frequency boost to the vocal exacerbated the problem.

Small Is Booty‑ful

A “lack of presence” in a mix usually means a recessed upper midrange, often paired with over‑abundant low mids. This is an ever‑present risk with material tracked in a small studio. To minimise the pickup of room sound and spill, you inevitably mic things quite close, with directional mics, and this brings the proximity effect into play. In this case, for example, the bass had been captured by an AEA R84A ribbon mic, and the figure‑8 pattern had introduced a lot of bass tip‑up. The brass overdubs were close‑miked with dynamic and ribbon mics, so the musicians could play in the room together and minimise spill, but likewise the sound was a bit too warm to cut through in a busy track.

There was, therefore, a sense in which the multitrack ‘wanted’ to sound soft. The close‑miked bass, brass and wah guitar were naturally rich in lows and low mids, while any attempt to push forward the midrange brought out the worst in the drum spill on the vocal track.

I used to think of source separation as a technology in search of an application, but having discovered that it can separate wanted audio from spill, I’m a convert.

Divide & Conquer

The obvious fix for the drum spill would have been to re‑record the vocal, and Robin has plenty of top‑end mics with which to do it. However, the live take had that all‑important vibe, which would have been hard to recapture later. Ditching the live vocal would also have meant discarding Robin’s meticulously recorded video footage from the original session, which formed an important part of his promotional plans.

Fortunately, help was at hand. I used to think of source separation as a technology in search of an application, but having discovered that it can separate wanted audio from spill, I’m a convert. I dropped Robin’s vocal track into Hit ’n Mix’s RipX, and a few minutes later, was rewarded with impressively clean vocal and ‘drum’ tracks. If you don’t change anything, these separated tracks recombine perfectly to recreate the original; the further you depart from this, for example by reducing the level of the spill track, or processing the vocal track, the more you risk artifacts being audible. In this case, the separation was good enough that I could lower the spill fader by 7 or 8 dB, and...