Hardware Reviews

Falcon IMF 100


The IMF 100 is an interesting project for Falcon Acoustics. A few years back owner Jerry Bloomfield decided to build an LS3/5A, the classic BBC monitor that has been around for years but which in Jerry’s opinion hadn’t been done properly because KEF were no longer making the drive units that were designed for it. So he started to make the drive units himself, you can read the full story here but what that doesn’t say is that his quest to make an LS3/5A that is as authentic and exactly as per the original license (now called Gold Badge) means that the speaker is pretty expensive for a compact monitor.

The IMF 100 attempts to make Falcon speakers more accessible by two means, firstly it’s what the company is calling a Complete@Home design, you assemble the speaker yourself which takes about 15 minutes per speaker. Secondly this model is being sold direct to the public so there is no margin built in to keep distributors and dealers happy. Which means that the IMF 100 costs significantly less than it would if it was fully built and sold through the conventional routes.


You get a real wood veneered, birch plywood cabinet with a post formed MDF front baffle that’s made in Italy, which is the most expensive part of any loudspeaker, and in this instance it’s a one eighth wave transmission line cabinet. IMF was originally a British loudspeaker manufacturer that specialised in transmission line designs so this is a logical way to go with its reintroduction to the world nearly four decades after the company’s demise. The drive units are the same ones that Falcon reproduced for the LS3/5A, a matched pair of T27 tweeters and B110 midbass units. One detail I particularly like about the latter is that you get machined retaining rings in anodised black aluminium that cover the steel chassis of the B110 and exert even pressure around its periphery. The crossovers are factory assembled and merely require pushing onto stand offs inside the cabinet, cables for the stainless steel terminal panel are already fitted and just slide onto the tabs of the various components. The quality of components throughout is very high.

The IMF 100 is a medium sized standmount speaker that stands 46cm high and weighs in at a healthy 12.5 kilos, it needs a bit of power to drive a low ish 86dB sensitivity but I got a good result with a Rega Elex-R that’s specced to deliver 90 Watts into 6 Ohms, so you don’t need a big amp. That said as I use a big amp for most of my reviewing, listening commenced with an ATC P2 (150W) which helped to reveal that this speaker produces pretty serious bass for its size and has a lovely mid and treble, the highs are a little restrained by modern standards but that makes for an easy to enjoy sound across a wide range of musical genres. Initial listening involved Crosby, Stills and Nash, Fourtet and Ghostface Killah and it all worked a treat. The speaker needs a bit of space behind it because the bass is generous shall we say, about 50cm worked in my room, but given that, they delivered all the important details required to make the music matter. Gregory Porter’s 1960 What came through with its tension and syncopation in full effect even though the IMF has that BBC style restraint associated with the LS3/5A. Neither is it the most dynamic speaker in its class but the quality of midrange goes a long way to making up for this, as does the bass which is solid and well extended.


It deals with high intensity stuff well, you can hear right into the eye of the storm that is Krokofant’s progtastic Q2, the speaker apparently unfazed by the density of information being conjured up, and unleashing it with the requisite propulsion. Give it something more refined like Joni Mitchell and Herbie Hancock’s take on The Man I Love (Gershwin’s World) and the timbre of voices and instruments is delightful, the melody too, the IMF 100 is a subtle loudspeaker that gets out of the way remarkably well. With the Rega Elex-R integrated the quality of vocals remains a strong point, even when the voice is that of Eminem it’s easier to comprehend what’s being said and the way it syncs so well with the beat. You need a bigger speaker to get the full power of tracks like The Real Slim Shady but I doubt there are many that can make the lyrics clearer.

The Grateful Dead’s Cumberland Blues (Europe ’72) is becoming a staple round these parts because the playing is complex enough to trip up components that don’t time well, but this speaker had no problem with the boogie factor. Letting its upbeat energy come to the fore in the superbly counterpointed guitars of a band at its peak. Keith Jarrett’s solo Carnegie Hall Concert is one of the best sounding recordings the artist has released, the piano being particularly physical in its presence. The IMF didn’t deliver all of the bass weight in the recording but did bring out the live atmosphere, the superb playing and the vocalisations that some find so troubling. I don’t think that they get in the way, it’s just Jarrett’s way of being in the moment.


I enjoyed the IMF 100 a lot, it combines the classic BBC midrange transparency with low end power and dynamics that an LS3/5A cannot compete with. It represents excellent value for money too, I don’t know of another transmission line speaker for the same price. The fact that you can’t try before you buy is the counterpoint to the keen pricing of course, it’s a leap of faith, but given Falcon’s track record in recent times not a very big one.


Type: 1/8th wave folded transmission line two-way loudspeaker
Crossover Frequency: not specified
Drive Units:
Mid/bass – 5inch Bextrene cone
Tweeter – 19mm Mylar dome
Nominal frequency response: +/ -3dB 38Hz – 20,000 Hz
Nominal impedance: 8 Ohms
Connectors: single wire binding posts
Sensitivity: 86dB 1w/1m
Dimensions HxWxD: 460 x 225 x 275mm
Weight: 12.5kg
Finishes: walnut or rosewood real wood veneer
Warranty: 1 year

Price when tested:
Manufacturer Details:

Falcon Acoustics Ltd
T +44 (0)1865 358001


standmount loudspeaker


Jason Kennedy

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