M-Audio Studiophile BX8 Studio Reference Monitor

The Studiophile BX8 Studio Reference Monitor from M-Audio is a highly precise biamplified active monitor with a sharp look, a cleanly defined sound and the means to gently tune the monitors to your room acoustics rather than vice versa.

The Studiophile BX8 Studio Reference Monitor from M-Audio is a highly precise biamplified active monitor with a sharp look, a cleanly defined sound and the means to gently tune the monitors to your room acoustics rather than vice versa.
Product PointsApplications: Audio and video production, gaming, desktop multimedia

Key Features: Eight-inch polypropylene woofer; one-inch silk dome tweeter; contour switches; balanced and unbalanced inputs

Price: $599 per pair

Contact: M-Audio at 626-445-2842, Web Site.


+ Versatile performer in most studio situations

+ Loud and clean

+ Frequency response charted at factory

+ Good construction for an under-$600 active monitor


- No digital input

- Response favors the high frequencies

The Score: A bright sounding, well-made powered monitor that can hold its own against the competition.
These monitors are as much at home in personal studios as well as commercial facilities, serving well in audio-for-video production, music recording and computer desktop audio/MIDI authoring. And at $599 per pair are comparable to the cost of passive monitors and separate amplifiers.

In fact, anyone involved in PC-based production using the stock self-powered "audiophile" speakers that came with the computer would do well to upgrade to a pair of BX8s. It just may reveal why mixes done on those computer speakers sound flabby and amateurish when played on other systems.

The BX8 can also be a mean performer for serious gamers, as the manual shows how to hook the unit up to function with a video game console.


To begin with, each BX8 is packaged with an individualized frequency response chart, evaluated and printed before leaving the factory. Even though it would slow down shipping and add expense, I wish more companies did this.

The frequency chart that came with my evaluation unit showed some enhanced brightness from 3 kHz on up to about 15 kHz. I predicted this would mean I had to tip the highs down a little, which I ended up doing.

The BX8 enclosure is constructed of medium density fiberboard (MDF) of very good quality, with a laminated vinyl finish layer outside and plastic foam inside for acoustic damping.

Many monitors today are constructed of MDF. It is nonresonant, it provides better strength than particleboard construction used in lesser-quality products, it is easy to work in the manufacturing process and more cost-effective than veneer ply cabinets.

The eight-inch polypropylene woofer admirably handles the mid- and low-frequency ranges, while a one-inch silk-domed tweeter carries the highs. The crossover frequency is 1.8 kHz. A blue LED in the woofer's mounting ring shows when power is applied to the monitor.

The rear panel contains the amplifier circuits, power supply, input jacks and several EQ slide switches. The inputs can be either XLR balanced, TRS balanced or TR unbalanced at line level. Each driver element has its own 65W amplifier, with a common volume pot regulating both. The back panel also includes a bass port that, according to the manual, vents frequencies below 30 Hz.

Circuit board design and loading is first class. The EQ shaping circuit is built around very capable 4558 low-noise op amps. The amplifier ICs are two high performance National Semiconductor Overture 3886 units; one for each driver and generously heat-sinked.

There are no digital inputs to the BX8. It is strictly an analog unit.

The power supply includes a mini-toroidal transformer for efficiency, and two 35 volt, 6800 mF electrolytic caps keep the amplifiers fired up without sagging on the bass notes. There is plenty of fused protection throughout the BX8, including one line fuse on the power receptacle, two on the PC board and a thermal cutout on the toroidal transformer.

M-Audio technicians have a definite eye for detail. The EQ shaping circuit is protected against hum by a grounded shield plate facing the power transformer, and all components carrying lethal voltages are socked down with heatshrink tubing and a potting compound to avoid mechanical buzzing at high SPLs. Even though the AC connections are protected, you should leave any service work on interior components to qualified folks just the same.

Switches on the back panel allow you to tailor the response of the BX8 to the particular room you are working in. The alterations are subtle and are used to shape the response gently rather than severely.

For example, the low cutoff switch has three positions, turning the corner at 37, 47 or 80 Hz. Setting the switch for 80 Hz emulates the response of a small bookshelf speaker, while the 37 Hz setting extends bass response for a little more in-your-chest thump during a mix. You won't get the same effect as you would with a dedicated subwoofer, but there is a definite difference. For a more conventional mix, the 47 Hz setting is proper.

Highs can remain unaffected or be dipped -2 or -4 dB at 5 kHz with the high-frequency compensation switch. A Midrange switch offers up a wide lift centered around 2 kHz to add a little presence to the program material.

Lastly, an Acoustic Space switch offers compensation of the monitor's response depending on its placement in a room and its proximity to walls and furniture.

For those who have typically used PC-type speakers in the past and placed them anywhere they would fit, the Acoustic Space effect requires some explanation

A speaker placed in the center of a room theoretically radiates in an isotropic manner, or into what is called the full sphere. Against a wall, the dispersion is contained in a half sphere, concentrating the acoustic energy forwards and theoretically increasing it by 3 dB. Against a corner, the mode changes to one-quarter sphere, as two reflecting surfaces now concentrate the energy forwards (source: Audio In Media, Stanley R. Alten, Wadsworth/Thomson Learning, 2001). Your PC speakers might sound weak just because of where you put them.

Essentially, this means speakers in a corner sound louder, but the increase actually happens in a select frequency range and not across the speaker's entire response.

The Acoustic Space switch gently reshapes the monitor's response by dipping the range between 500 and 900 Hz either 0, -2 or -4 dB, depending on the placement of the BX8 in the mixing space.

So a position on this switch is selected depending on whether the BX8s are placed on a stand, on a shelf, or on the mixer overbridge facing you.

In Use

I used a pair of BX8 monitors on a variety of sources, including a Hercules soundcard on a PC; an Earthworks SR71 microphone preamped through an Allen & Heath WZ20S audio mixer and recorded to a Sony TCD-D8 portable DAT recorder; and a simple, inexpensive portable CD player with a line out connection.

The microphone and mixer provided the most detail. As the SR71 boasts flat response to beyond 20 kHz, I had an uncolored representation of my voice. I found it most pleasing with the high-frequency compensation at -4 dB and the midrange switch flat. Since the speakers were set on a tabletop, I also took out 4 dB on the Acoustic Space control.

My vocal recording carried power and clarity. As there is not a lot of very low (< 80 Hz) bass energy in the male voice, the low cutoff switch revealed nothing on my vocal recording.

The computer soundcard fared better in evaluating the low end. Launching a demo version of the music environment program Reason from Propellerhead Software, I set up a bassline synthesizer with the filter set for low resonance and lots of fundamental tone. With the Low Cutoff control set to roll off at the 80 Hz setting, the BX8 followed along wonderfully without the speaker cone bottoming out. At the 37 Hz setting, the increase in acoustic energy was apparent, but not grossly so.

Lastly, an assortment of CDs played on the portable unit. A bass-heavy recording of the "Mars" movement from Holst's The Planets sounded balanced and well-defined without going cloudy on me.

A CD remastering of the classic '60s Perrey-Kingsley electronic album, The In Sound From Way Out, played through the BX8s revealed something I had never heard before: ambient noise and room tone where the live musicians were recorded.

The only time I felt compelled to change the switches to alter the response was while playing the CD pressing of the Beatles' Sgt. Pepper's album; ironically the one album all others are held up to in comparative judgment. I don't fault the album at all, but the way the monitors interacted with my room. After all, that is why the switches are there.

I wish I had the opportunity to do an audio mix for video on the BX8. As the units are magnetically shielded and worked as well as they did with my computer soundcard, I would predict them to be admirable performers around computer-based editing systems running such programs as Adobe Premiere or Final Cut.


There are many powered monitors available, and in this price range our attention tends to head towards names such as Alesis, Event Electronics or Behringer, among other excellent manufacturers.

As such, M Audio has to exert an effort to get you to examine the BX8. But once they get you there, you should like what you hear: Fine control over the frequency contour of the monitor, plenty of clean power and a price that places it on par with other manufacturers.