Denmark's Dynaudio Acoustics started out as an audiophile speaker and driver manufacturer. In recent years, the company successfully branched out into producing studio monitors, especially higher-end systems for professional film and broadcast applications. At a street price of less than $1,000 a pair, Dynaudio's powered BM5A is one of the company's most affordable monitors.
FIG. 1: Dynaudio Acoustics'' BM5A houses a 6.9-inch woofer and a 1.1-inch soft-dome tweeter, each powered by a 50W amplifier.
The BM5A (see Fig. 1) is a 2-way biamplified monitor featuring a 6.9-inch woofer and a 1.1-inch soft-dome tweeter. Each speaker in the well-built black enclosure receives power from its own 50W amplifier. Both amplifiers have thermal overload protection, and the woofer amp has an additional built-in limiter circuit.
An overload LED on the speaker's front glows orange when bass limiting is activated, and lights red when thermal shutdown is activated. A front-mounted green diode is the power indicator. There is no grille cloth or mounting hardware on the speaker's front panel. A protective three-legged metal piece is mounted over the tweeter.
The BM5A's rear panel (see Fig. 2) includes a fused IEC AC power-cord connector and power switch, a +4 dBu balanced XLR input jack, and several small switches. A grouped array of three equalization switches can be set to flat or can be set to provide bass shelving (± 2 dB at 150 Hz), midrange cut (-2 or -4 dB at 450 Hz), and treble filtering (± 2 dB at 2 kHz and above) to compensate for room acoustics.
A highpass filter switch can be set to flat when using the monitors alone. When pairing the BM5As with a subwoofer, the switch can be set to 60 or 80 Hz cutoff points. A sensitivity switch offers three positions for input sensitivity: +4 (for high-output sources), 0, and -10 (for low-output sources).
A large heat sink protrudes from the rear panel, which also contains a bass port. The port measures 2 inches in diameter and is tuned to a resonant frequency of 55 Hz. The BM5A is designed for use as a close- or mid-field monitor and can be positioned three to nine feet from the ideal listening point. Dynaudio recommends its BM10S or BM9S subwoofer for use with the BM5A.
FIG. 2: The BM5A''s rear panel includes an array of three -equalization switches that can be set flat or provide bass shelving, midrange cut, or treble filtering.
I set up the BM5As in the control room at my Guerrilla Recording studio, and compared them with two sets of passive monitors that I have relied on for many years: the Tannoy PBM8s and the Event 20/20s. The active surface of the woofers in both of those monitors measures about seven inches across, compared with the 5-inch surface of the BM5As. The Event 20/20s have 2-inch ports in the front, and the Tannoy models have rear ports, which I blocked with foam.
I use an Adcom GFA-555 to amplify the passive speakers. I normally use a subwoofer and a stereographic equalizer with my studio monitors. For these tests, the subwoofer and the EQ were disabled. Midrange and bass EQ settings were set to flat on the BM5A for evaluation purposes. High-frequency EQ was set at -1. A level setting of +4 most closely matched the BM5As to the other studio speakers.
During setup, the switches and labels on the rear panel struck me as unusually small and hard to read. But for most installations, those selectors will be set only once or twice and then forgotten. The BM5As produced a barely audible high-end hiss when powered up. I never detected a midrange bump or crossover distortion near the 1.5 kHz crossover center frequency.
Magnetic interference wasn't an issue when the unit was placed next to a standard VGA computer monitor. The BM5A manual is straightforward and helpful. It guided me smoothly as I set up the monitors and learned their controls.
On some sparse electronic music mixes by composer Joel Pickard, the Dynaudio close-field monitors offered superior performance on synth bass notes and on some complex low rumbles. Compared with my monitors, it was much easier to hear system noise, compressor pumping, and other artifacts in Pickard's mixes through the BM5A speakers.
I used the BM5As during various mix sessions, mainly as a playback reference for checking a final mix. On several occasions I picked out flaws, distortion in a mix, or other balance problems during one pass on the BM5As that I hadn't while mixing the source material. A single BM5A also worked well as a flat reference monitor during controlled laboratory-style testing of microphones for another EM article.
To dig into the BM5A's character more deeply, I compared it with my other monitors while listening to a CD of Nino Rota film music called Club Foot Orchestra Plays the Music of Nino Rota (Rastascan, 1997). That disc was recorded at my studio and mixed on the Tannoy PBM8 monitors. The group includes a standard jazz rhythm section with acoustic or fretless electric bass, violin, various keyboards, and horn-rich melodic arrangements featuring trombone, trumpet, sax, and clarinet.
The BM5A speakers were plainly brighter than the Tannoy monitors when reproducing the top end of horns, cymbals, and reverb in the mix. That contributed to the feeling of a larger and airier soundstage, which is almost always a good thing for acoustic music. The alto sax, however, sounded a bit hollow, and it lacked midrange warmth between 400 and 800 Hz.
Among the trio of speakers, the tone of midrange instruments such as bowed bass, trombone, alto sax, and snare was more accurate on the Tannoy and Event monitors. The bass drum (a double-headed jazz kick that is generally light in the mix) sounded great through the BM5As. Electric and acoustic bass fundamentals were also well represented through the BM5As. In fact, some of the low notes on acoustic bass were a bit overpowering when bass filtering was turned off.
For the multivoice ensemble arrangements of the Nino Rota CD, I preferred the warmer mids of my regular monitors. But there is no doubt that the BM5A pair revealed important details in the highs and lows and delivered a richer timbre at the extremes of the audio spectrum.
The BM5As occasionally highlighted minor distortion and other artifacts that had previously escaped my attention. The speaker exhibited a wide and even sweet spot, and the stereo image remained constant while I moved my head from side to side or when I moved closer or farther from the speaker array.
I made some trial mixes to gain additional perspective on the suitability of the BM5As for studio mixing. I selected a dense rock track (“Sick Fascination” by the band Whore) that has drums, industrial percussion, bass, distorted guitar, keyboards, and aggressive female vocals. I first constructed a mix on the BM5A pair, determining panning, reverb, compression, EQ, and basic mix levels.
It was easy to get the rock kick to sound sharp and powerful on the BM5As. As an engineer who believes that great studio monitors can lull one into false confidence, I was concerned that the BM5As weren't making me work hard enough on this crucial mix element and that the monitors' abundant low end could result in mixes that were lean on bass (especially in smaller control rooms).
The BM5As revealed a wealth of room details in the drum and percussion tracks. The ability to hear ambient nuances is important to me when mixing in any musical style. On the Whore mix, the improved resolution of the busy metal percussion, drums, and bass was especially helpful when balancing the rhythm section. The BM5As effortlessly highlighted popped plosives in the vocal track and some gritty breakup in the electric guitar and vocal.
When comparing the two mixes of “Sick Fascination” in my mastering lab, the Event monitors produced a bigger-sounding mix with more cohesion and support for the vocals. As I suspected, there was not enough kick drum and bass on the BM5A mix. And although I liked the higher vocal setting of the mix created on the BM5As, it seemed that the monitor created a gulf between the more prominent vocals and the instruments, which were bass lean and drier in the mix.
The second test mix focused on acoustic layering, using basic tracks from the Two Foot Yard song “Patchen.” Once again the BM5As made mixing a breeze on this subtle arrangement of percussion, cello, viola, violin, accordion, and layered female vocals. Within that spacious soundscape, the BM5A's fine resolution made tweaking reverb easy, and levels seemed to fall into place effortlessly.
After comparing those mixes, I felt that the bigger sound of the Dynaudio monitors produced a mix that came together quickly, yet sounded flat and less defined. In particular, the vocal level on the BM5A mix was too low, muddy, and dry, and low-end elements (such as cello and bass drum) were mixed too low. Although the kick sounded fine in the control room, it was almost inaudible over mastering speakers. The Tannoy monitors produced a better string balance and noticeably improved vocal prominence.
At loud levels, the BM5As performed well without obvious bass compression or overloading. The sound was certainly impressive on mastered mixes, much more so than on the more midrange-enhanced Events. The BM5As sounded more detailed at high SPLs than the Tannoy monitors.
Dynaudio Acoustics' BM5A powered monitors bring audiophile frequency response, exemplary spaciousness, and a clearly enhanced level of detail to the mixing and monitoring experience. As with the passive Dynaudio BM15s that I use daily in my mastering lab, desirable nuances (ambient and artificial reverb) and undesirable elements (tape or tube saturation and overload distortion) are often more apparent on the BM5A monitors. Their superior definition is accomplished with smooth and natural high-end response, thanks to a tweeter design that is very listenable and accurate.
The BM5A monitors sound bigger than they look and provide clean power handling, transparent highs, and above-average bass response. For premastering, post-production, soundtrack work, or location recording, I give the small and mighty BM5A my highest recommendation. The BM5A would also make a revealing reference monitor for checking mixes or impressing anyone in your control room. And if you want to hear anything or everything you've recorded in full audiophile detail, give the BM5As a serious listen.
Myles Boisen is head engineer at Guerrilla Recording and The Headless Buddha Mastering Lab in Oakland, California.
active close-field monitor
OVERALL RATING (1 THROUGH 5): 4
PROS: Superb resolution and detail. Above-average bass response for enclosure size. Clean amplification with ample headroom. Wide and even sweet spot. EQ and level-adjustment switches.
CONS: Small rear-panel switches and labeling.
Dynaudio Acoustics/TC Electronic (distributor)
BM5A SPECIFICATIONS Analog Inputs (1) balanced XLR Woofer 6.9" one-piece molded polypropylene cone Tweeter 1.1" soft dome Crossover 6 dB/oct @ 1.5 kHz Frequency Response 50 Hz-21 kHz, ±3 dB Amplifier Power woofer: 50W; tweeter: 50W Maximum SPL @ 1m 115 dB peak Input Level (85 dB SPL @ 1m) -16 dBu RMS (0 dB setting) Power Consumption idle: 10W; maximum: 90 W Resonance Frequency 55 Hz Weight 19.2 lbs. Dimensions 7.3" (W) × 12.5" (H) × 12.5" (D)