Don't you just love things that are simple? Aston Microphones believes that reflection filters should be simple — easy to use, lightweight... and purple. Since the introduction of the SE Electronics Reflexion Filter in 2006 [Tape Op #56], reflection filters have become more visible in studios — with all of their accessory arms, adapters, and various pieces that inevitably get piled up in the corner behind the mic stands. Reflection filters are intended to absorb and diffuse some of the sound energy that would otherwise enter the capsule uninhibited from the rear side of the mic. Unlike any of the other reflection filters I've seen on the market that primarily handle sounds approaching along the horizontal plane, the hemispherical, bowl-like Aston Microphones Halo filters sound approaching the rear of the mic from all angles, which is a significant advantage over designs that fail to address reflections from low-ceilings in bedroom-sized spaces.
When I first pulled the 21'' × 18'' × 9'' Halo from the box, I was not surprised that it was purple, but I was surprised at its sturdy, yet low-mass form. Including the mounting hardware, the Halo is lighter than a standard tripod mic stand, which makes it notably less clumsy than some of the heavier reflection filters on the market — if you've used these, you know what I'm talking about! The Halo's purple colored, acoustically architected structure is molded from a felt-like material made from PET (polyethylene terephthalate) fibers manufactured from recycled plastic bottles. The softly sculpted unit looks rather inviting — and much less like some kind of Imperial weapon from Star Wars, like others before it do. The mounting hardware is made of finely milled metal, and it's easily adjustable. The hardware allows you to use a single mic stand to hold the Halo and the mic, or to use two separate stands, one each for the Halo and mic.
In use, the Halo attenuated the sound of the room in vocal tracks recorded with a large- diaphragm condenser mic in cardioid mode — the foundation for my evaluation. In addition to using the Halo in standard studio scenarios, I really wanted to see what the reflection filter could do in some of the worst rooms I could find at home. As to be expected, my kitchen and bathrooms had the highest incidences of unwanted room reflections.
It wouldn't be my first choice to track vocals in a small, tiled, 25 sq ft bathroom, so this is where I started. I should note here that the amount of filtering at the backside of the mic is adjustable by sliding the mic closer to the inside of the Halo's bowl shape. Because the width of this bathroom is only 4 ft, and the corresponding reflections were so fast, I opted to slide the mic's back as close to the inside of the reflection filter as it would go (less than an inch) and really get my head as far into the bowl of the Halo, without my mouth being too close to the mic. The difference in these test vocals with and without the reflection filter (both recorded at the same distance from the mic) was striking. The Halo really helped to mitigate the washy character of the bathroom, and it sounded pretty damn close to an iso-booth!
Our large, open kitchen with 10.5 ft ceilings is dimensioned like a geometric cube — also not ideal for recording. Again, I played with the mic spacing within the reflection filter to "tune" how much room sound I wanted to let in. And again, comparisons revealed an improvement in vocal presence and clarity. Our back bedroom is low, with 7 ft ceilings — a definite no-no for recording a vocalist that's over 6 ft tall. I did it anyway, and it worked. Another note — the Halo's bowl-like structure is wider than tall. It was interesting to experiment with rotating the filter 90° to get a little more filtering on the ceiling/floor reflections than the wall reflections — again, really helpful results. In summary, I was able to capture forward-sounding vocal tracks in really bad rooms!
Back in a professional studio environment, the Halo performed well and was incredibly easy to set up. At times, depending on the mic choice, I had to grab an extra stand for a pop filter — which is no big deal for me, because I'll often do that anyway. I prefer the sound of an open- roomed vocal for some music genres, but hip hop artists, for example, typically like a very "up front" and isolated vocal. In the past, the iso-booth was an absolute requirement for recording vocals in this genre, but with the Halo's filtering in our main live room, I feel like I can capture a less "boxy" sound than tracks recorded in the iso-booth. Voiceover work in our smaller room and in my project studio also benefitted from the Halo. Unfortunately, with both hip hop and voice work, artists and voice talent often need to be able to read from portable devices and paper scripts. Like all reflection filters that I've used, the Halo obscures the field of vision somewhat, which can be challenging at times.
A reflection filter can be a handy tool for partial isolation of a vocal mic when the singer is tracking in the live room with the band. In other words, the filter can reduce the instrument bleed making it into the vocal mic. But interestingly, it also works the other way around. On one occasion, I was able to use the Halo on the singer's mic to prevent extraneous bleed of the scratch vocal into the drum overheads.
In addition to vocals, the Halo spent time on guitar amps, bass drums, room mics, and other sources. On guitar amps, surrounding the backside of a (figure-8 pattern) ribbon mic with the Halo made for some interesting results (both on and off-axis). An LDC in cardioid pulled deep into the Halo and placed in front of the kick drum was punchier than sans filter, and even the snare bleed was reduced. An omni room mic between the drum kit and a flat wall offered a bigger feel with a nicely controlled cymbal wash.
The Halo is a must for tracking vocals in project studios with less than ideal room characteristics; and for day-to-day studio use, it's indispensable to have a lightweight, portable, adjustable reflection filter that can be set up quickly during hectic sessions. The only criticism I have is that the Halo's mount relies on 3/8'' European threading, so us Yanks have to buy a $5 adapter for our 5/8'' mic stands. But the Halo is purple — a great color for sound treatment and artist vibe!