Bose 101 Mini Monitors
Bose is a multinational. The company is essentially American, but Bose designs also come out of their factories in Holland, Japan and the UK. The F1 power amplifier we looked at recently was an example of Bose UK in action under the dynamic Walter Miraurer. Meanwhile Bose's range of products covers much more than their controversial Hi-Fi speaker. To put you in the picture, founder, Doctor Armour Bose's ideas about how stereo speakers should be deployed are a shade heretical. However, none of this need alarm you - the 101 speakers reviewed here aren't controversial, just innovative.
The 101 is a compact micro-monitor encased in an unprecedentedly solid plastic enclosure. If you dropped it out of a window onto concrete, it would probably survive, whereas a wooden cabinet certainly wouldn't. The single-drive unit is one of Bose's well known 4" 'full range' models, the D22A. It's the same one you'll have seen in multiples in 802 enclosures. Unusually for a speaker of this size, the driver is Thiele-loaded by a small duct.
Returning to mechanics, one of the 101's most desirable features is flexible deployment. On the underside, a pair of sturdy, threaded-inserts are set deep in the plastic. Into these, you can screw the 'GMK-2'. This fellow is a ball & socket assembly- so you can angle your 101 with complete freedom anywhere in 180° solid-space, in other words, over a hemisphere. In turn, the GMK-2 screws into a standard mic stand thread. The big question is 'Do I have a spare pair of mic stands?' But at least if you have to go out and buy a pair, you're not spending money on dedicated speaker stands; if you decided after all that you didn't need the 101's on stands, you'd be able to find a use for the mic stands.
Failing this, there's the 'GMA-2' - also with a ball & socket head, but this one is attached to an extension tube terminating in a G-clamp, so you can hook up the 101's wherever there are shelves, chairs, tables, flightcase lids - indeed onto anything up to 1½ inches wide. With either accessory in place, the height and angling of the units is wholly adjustable. And best of all, no tools are required - it can all be done with fingers alone....
The 101's packaging also has sensible features that suggest an awareness of grass roots usage. The push-on grilles, for example, seat deeply into the moulding, so they won't fall out easily when hit from the side. They're also made of steel mesh, but this won't significantly colour the sound because it's pressed into a very rigid form. Yet, if you happen to tread on a 101 (Hands up everyone who has speakers lying on the floor) the grid gives way to cushion the impact, then springs back into shape again.
From the aesthetic angle, smart red nylon covers the grille and contrasts well with the enclosure's lillywhite plastic, all rather reminiscent of an exotic Italian ice cream. Round the back, you can link up via a standard jack, or more simply, push bare wires into the quick-connect terminals. The jack is airtight (so the low frequency loading doesn't alter whenever the jack plug is inserted or removed), and all terminals are recessed, just enough to protect them from damage, but not enough to make them at all awkward to get at. Another neat touch is a blank hole hidden behind the self-adhesive serial number label: it's all ready to accept a male XLR socket if this is your preferred connector.
A single full-range driver needs no crossover, of course, but the 101 features a simple network which amongst other things, gently limits the power input at low frequencies. Connections here are wire-wrapped, then soldered, but the speaker connections are wire-wrapped only, presumably to ease the task of replacing the driver - an unlikely requirement, as we'll see.
Listening on 101s encompasses the general qualities we've come to expect from the single-driver configuration. Centre stereo imaging is above average, while extreme frequencies are inevitably lost, which tends to bring the midrange sound forward.
Homing in on the specifics, the 101 displays some interesting qualities. To begin with, it's virtually impossible to force the driver into bottoming difficulties on high level, low bass, even when given the New York electro-funk treatment. The integral low bass filtration in the crossover network probably helps here, but oddly, not at any expense to the bass sound. For its size, the 101 shows a remarkably physical presence, indicating that there's a significant audio output below 100Hz, and on this score, the 101 is certainly ahead of its competitors.
On the other hand, the bass is certainly less accurate; but it's for you to weigh up which facet matters most. Specifically the bass sounds 'lumpy', and overall, the sound is a little too forward (at least for my English ears) and slightly biting at high levels. At the same time, it has vitality, and when listened to close up, you'll learn or discover plenty of interesting facets of vocal techniques; there's a lot of detail in this zone. The other obvious quality is 'hardness' when played at high levels. In small doses, it's exhilarating, and if you're using other speakers as a cross-reference then this won't worry you, but it's not healthy to live by 101 alone (or any other micromonitor) if your main application is the analysis and perusal of music, rather than listening per se.
The 101 is unusually unfussy about how it's driven. It manages to sound loud enough on low power amplifiers (eg. 15 watts), yet can cope with a 250 watt amplifier driven into clipping. This is usually very out of order, but the 101 takes the punishment without a grimace. For our tests, we wound a Turner B502 amp deep into overload, and achieved nothing more than ear-ripping distortion - most of it from the power amplifier. The 101 is therefore unreservedly recommended for monitoring heavy metal, or playing a guitar through; it's very thrash-able!
Part of the secret lies in the drive unit's unusually low impedance, namely 2 ohms, and the crossover topology. At low levels and mid frequencies, the power amplifier sees a lower than average load impedance via the various reactive networks, which increases the power input by 6dB or more over a conventional 8 ohm speaker. At higher levels, the voice-coil resistance presumably rises quite sharply, otherwise there'd be problems with power amplifier protection circuits 'leaping in'. Nonetheless, with a nominal impedance of 6 ohms, you should aim to use power amps capable of driving into 2-5 ohms, if not less, to obviate the possibility.
In any event, the low frequency portion of the signal is wired in series with an incandescent tube - a glorified light bulb if you prefer! This gizmo has a similar characteristic to a loudspeaker voice-coil (ie. resistance rises sharply as it heats up), so in effect, there are two, built-in 'compressors' providing exceptional resistance to overloading. From a purist viewpoint, this spells lots of colouration when the 101 is overdriven, but as the amplifier is likely to be into the overload region, this scarcely matters. The ruggedness this lends will in any event be highly praised by readers in situations where equipment is likely to be misused or overdriven, by accident or otherwise. Incidentally, when the internal incandescent tube is triggered by an excessive input, you'll see an orange flash reflected out from the ducting - a rather crafty piece of design, as the tube is mounted at the opposite end of the enclosure. If you value this facility, you'll need to remove the grilles (for visibility), and also take care not to displace the internal acoustic lagging so that it obscures the reflected light.
The Bose 101 comes close to being a 'Go anywhere, do anything fun-speaker', with the trade-offs this inevitably implies. It's physical ruggedness outspecs other micro-monitors, and it can be successfully hooked up to everything from a cassette to a professional monitoring set-up. To sum up, it's the ideal speaker for musicians who need a general purpose, 'no fuss' monitor with a basic Hi-Fi performance. In this sense, the 101 is a veritable micro-jeep in the realm of monitors.
The Bose 101 monitors retail at £129.95 per pair including VAT.
Further details from: Bose (UK) Ltd., (Contact Details).
Review by Ben Duncan
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