Review: Acoustic Technologies SFM07A
A wedge that likes to keep a low profile.
By Mark Woods
26 September 2013
What an excellent little wedge this is. And I mean ‘little’ in the nicest possible way. Acoustic Technologies’ SFMO7A is a self-powered foldback wedge that has been designed to be compact, light and easy to use, while still delivering the highest quality sound for professional applications. Based in Queensland, Acoustic Technologies is good at making small speakers that deliver quality live sound. With both design and manufacture done in Australia, I was very impressed with its AT FR21A 12-inch woofer and horn speaker I reviewed back in Issue 94. The SFM07A is part of the same family of speakers and it arrives as a little brother for the larger SFM09 powered wedge.
SIZE MATTERS
Its outstanding features are: size, profile, weight and simplicity. Width (462mm) and depth (350mm) are compact enough but the height of only 194mm makes these very low-profile wedges indeed, in fact they almost disappear on a stage. At 13kg a piece, they’re very easy to carry and position. The cabinet is a distinctive shape with the drivers mounted behind a rounded grille so they fire upwards at an angle of approximately 30° to the floor. The rear of the cabinet (that faces the audience) has an angled panel at the top but is otherwise unadorned — no ports, lights, logos or interesting shapes. On one end of the cabinet is a flush-mounted handle that can be accessed from either side of the hand grip. The other end has a recessed panel containing the power socket and XLRs for input and link. No EQ, no input options, no indicator lights… not even a power switch.
The physical design of the speaker may be understated but it looks both tough and professional. The cabinet is made from 12mm and 18mm birch ply with a shiny black textured finish, described by Acoustic Technologies as Acousticoate Black Elastomer. The texturing is quite pronounced and gives the surface a sparkly appearance in some lights. It feels like it would take a lot of punishment before chipping. The perforated steel grille is finished in black powdercoat paint and feels like it could survive being stood on by a performer in a rock band trying to look taller during the show (I hate the way they stand on wedges). The acoustic foam below the grille should protect against flying drinks…or Dirty Three spit.
DRIVING FORCE
Beneath the steel grille lurk two 6.5-inch drivers mounted on either side of a one-inch compression driver coupled to a proprietary waveguide. High frequency dispersion is quoted at 90° horizontal by 60° vertical. Power for the drivers is supplied by an built-in, single channel, 200W Class D switch-mode power supply amplifier. The drivers are passively crossed over at 1.6kHz. Acoustic Technologies has invested considerable time and expertise in the crossover and gives it credit for the speaker’s smooth response across the midrange. Also hidden inside the cabinet are protection circuits for excess heat, over current, HF input level and a limiter.
NEED TO KNOW
Acoustic Technologies SFM07A
Self Powered Stage Monitor Loudspeaker
TESTING TIMES
I started off testing the SFM07A with vocal mics and pre-recorded music and was struck by two initial impressions. Firstly, I noticed the brightness and clarity of the voicing. I particularly like the HF driver in this speaker: there’s a real hi-fi quality in its detail and fast transient response. This results in a sound that is crisp but not harsh, the 2kHz to 4kHz octave is well controlled, and the mids below that are smooth — I was reminded of Acoustic Technologies’ FR21A. Secondly, I noticed that if you give the SFM07A a big, roadie-strength, ‘Check-1-2’ right on the mic you can hear some limiting and a bit of overloading, but the bottom end is surprisingly good — not hugely deep but with enough body for most vocals. The frequency response is quoted at ±3dB between 100Hz and 16kHz and sounds commendably flat overall. The low-end response is the only potential compromise in the design: the cabinet is quite small and a pair of 6.5-inch drivers has a limit as to how much low-end power they will reproduce. Volume is not a problem; these things are loud enough for anything short of extreme volumes. And fidelity is not an issue either; the sound quality is very high, the dispersion is smooth across the front of the cabinet and they are stubbornly resistant to feedback. But there may not be enough sub-100Hz energy for some users, particularly loud bands. Whether it matters or not depends on the situation — if there’s plenty of bass in the PA and the SFM07A’s are being used for stage vocals only then they may not seem bass-shy; but if the act wants lots of bass power from the wedges for bass guitar or stomp boxes for instance, then it may not be there.
ENJOYING THE VIEW
The first live show I did with these was an outdoor spoken word/small acoustic acts event and they were perfect. The performers were happy to comment on the sound quality and I liked the looks. I don’t like wedges blocking the view of the lower part of the artists but with the SFM07As the profile is so low they can hardly be seen on stage, and what you can see looks neat and discreet. Next, I took one along to the Theatre Royal in Castlemaine when Something For Kate was playing. I thought I might try it on a vocalist, but once I’d heard the volume they were generating I decided to use it as the foldback listen wedge. In this application it was nice and clear in the mids and highs, but struggled to compete with the stage sound down low. I then took one to the Kelly Country Pick in Beechworth and used it as the centre wedge for the whole event. Once again the size/looks were great and with audio that was based on condenser mics, pure sounds and beautiful vocals — all delivered at natural volumes — the SFM07A really shone. Despite the crisp sound I was getting useable levels from the foldback and it took some provoking to get it to become unstable. It’s also significant that I didn’t hear the need to put any external EQ over the speaker — just plug it in and start playing.
MAKING THE CASE
With a RRP of $1395 the SFM07A is not bargain-basement stuff but you do get a great-sounding speaker that’s ruggedly constructed, unobtrusive on stage, and easy to use. They should appeal to production supply companies, especially those working on TV, fashion shows or corporate presentation work, or any situation where discreet looks and high-fidelity win over sheer grunt. They should be compulsory for folk festivals. Lots of smaller acts or duos that carry their own gear would also appreciate the quality and convenience. I like the no-compromise, stage monitor-only design and the overall rugged simplicity which should guarantee a long working life. Acoustic Technologies is confident enough to offer a five-year warranty on the components. Top quality Australian made speakers.
RESPONSES