M‑Audio's first foray into active nearfield monitors is certainly extremely affordable, but could it be a false economy for the home recordist?
The SP5B is an active nearfield monitor, measuring 350 x 166 x 200mm (hwd) and weighing 5kg. The front panel of the vinyl‑covered MDF cabinet carries a 5.25‑inch polypropylene bass/mid‑range driver, and a one‑inch silk‑dome tweeter. Both drivers are magnetically shielded.
The tweeter's mounting stands proud of the baffle such that the axis of the voice coil is some 30mm in front of that of the woofer. This also makes it very vulnerable to damage as the silk dome rises slightly proud. There is an unusual wave guide which can be angled to alter dispersion and directivity as required.
The metal rear panel supports the internal electronics and is fitted with an IEC mains inlet, complete with integral fuse holder and a rocker switch. Both XLR and TRS quarter‑inch jack sockets provide balanced line‑level audio input, and the two inputs are mixed internally with a single level control.
A large 1.5‑inch flared port is positioned at the top of the rear panel and extends about four inches into the cabinet. Data provided with each loudspeaker showed a fairly flat frequency response, although closer inspection of the graph axes revealed that the plot only covered the range from 200Hz to 20kHz, and a dynamic range from 20 to 120dBSPL. In fact, the speaker's on‑axis response fills a ±5dB window between 220Hz and 20kHz, with broad dips centred around 4kHz and 12kHz. The response peaked at 1kHz and seemed to tail off gently from there down, falling 8dB by 200Hz and looking like the trend would continue.
The SP5B sounded pretty much as you'd expect, given its frequency response. In a free‑field situation the initial impression was of a small boxy‑sounding speaker with a very forward mid‑range and a generally weak bass response — the handbook insanely suggests a frequency range of 33Hz to 22kHz, but doesn't specify the measurement limits! You get more bottom end if you place the speakers close to rear or side walls, although not too close, as most of the LF comes from the rear port, which needs room to breathe.
The treble is clean and well extended, and the stereo imaging is precise and stable — an advantage of the small cabinet size. The speaker also sounds very fast, but is quite two‑dimensional — there is no real depth and it fails to convey any impression of room size.
The amplifiers generate more than enough output level for nearfield use. An input of 200mV (‑12dBu) is enough to produce full output with the gain controls fully up — a normal +4dBu monitor signal required the speaker's gain controls to be turned over half way down, which made balancing the stereo image a fiddly procedure.
Like many companies before them, M‑Audio claim that 'after long research and development' the SP5B changes 'the concept of nearfield reference monitoring', and is 'designed to overcome all the limitations of conventional nearfield reference monitors'. I think not! With the lack of any real bass energy, the SP5B does create an impression of 'transparency', but I really don't think it justifies the 'reference monitor' tag. I found mixes performed on this speaker didn't travel very well to other systems, and it was poor at revealing the details in complex mixes. Even choosing reverbs was difficult, as the speaker didn't seem to reveal any differences between my Lexicon's programs!
The SP5B has no real UK competition at the price. Most two‑way active systems cost at least a hundred pounds more — the Genelec 1029, Yamaha MSP5, Tannoy Reveal Active, or HHB Circle 3A, for example. But a comparison with any of these would quickly reveal the weaknesses of the SP5B. I find it hard to recommend the SP5B, and would suggest you saved up a few hundred pounds more to buy a more dependable monitoring system.