In this On Test article Julian Rodgers auditions the Fluid Audio FX80 and finds a monitor which for a small price delivers a sound which is anything but small.

The Fluid Audio FX80 is the larger of the duo of keenly priced coaxial 2 way monitors from Fluid Audio. The 80 features an 8 inch mid/bass driver coaxially mounted with a silk dome tweeter which unlike some other coaxial designs is mounted in a 75mm waveguide which is mounted in front of the bass driver rather than in the centre of it. The monitor is enclosed in a relatively large mdf cabinet which is front ported and is powered by class D amplifiers and DSP based crossovers.

The specs promise impressive performance with the bass extending to a quoted -3dB at 35Hz and the advantages of point source accuracy would make this an impressive looking full range monitor but the headline here is just how little these monitors cost. They are currently on sale for $275 each. That makes these very interesting indeed.

The Drivers

The coaxial arrangement of the drivers is the most interesting aspect of these monitors to me as by using a tweeter in front as opposed to a tweeter in the centre of design the doppler modulation issues which can affect dual concentric monitors is neatly avoided. The advantages of a dual concentric design are easy to understand, conventional speakers with more than one driver suffer from phase issues because of the different path lengths from the tweeter and the woofer respectively, a problem often exacerbated by people putting 2 way monitors on their sides. These time of arrival differences are neatly avoided if you put both drivers at the same point in space. The problem has always been how to put two drivers in the same place without them interfering with each other.

In a two way design with the tweeter mounted in the centre of the cone the bass driver forms the waveguide of the tweeter and if the bass driver is moving, particularly if it is reproducing low frequencies, this movement will modulate the HF information being reproduced by the tweeter. For example if a conventional two way dual concentric monitor is playing 40Hz and 10KHz tones at the same time, the 10KHz tone would have a slight 40Hz vibrato applied to it by the movement of the bass driver. By mounting the tweeter in front of the bass driver and installing it in a rigidly mounted waveguide this doppler shift can be avoided.

The Cabinet

The monitors is physically quite large at 10”x13”x12” (WxHxD). The cabinet is vinyl covered MDF and as it is in the woodwork that I usually become consciously aware of a monitor which is built to a price I approached the “knock test” with only moderate expectations. Rapping on the panels of a monitor with your knuckles is an extremely revealing test and while the quality of components can be difficult to discern by a quick inspection, there’s no hiding cheap woodwork! These cabinets are surprisingly sturdy and while the contoured plastic front baffle is less substantial, it’s a long way from being the structural liability that the lightest examples of a moulded plastic baffle can be.

Back Panel And Electronics

The controls on the back are sensibly chosen. With analogue XLR, TRS and phono inputs available, IEC power and a rear mounted power switch along with a detented trim knob and a set of dip switches for voicing control. The class D amplifiers supply 50W to the HF and 60W to the LF respectively and like some other lower cost amplifiers I’ve heard there is a hiss present, though low in level and something I only noticed when the auto muting feature kicked in after several minutes. In use and passing audio the noise is inconsequential.

The crossovers are implemented in DSP rather than using analogue components and looking at the specs this crossover looks like it has been carefully designed to ensure the coaxial arrangement of drivers perform correctly. The crossover, set at 2.75KHz comprises a pair of filters, one at 36dB/oct and the other at 48dB/Oct in a Linkwitz-Riley design. These slopes are unusually steep and have been chosen because the tweeter’s waveguide forms such a small baffle from which the HF content radiates. Lower frequencies require a larger baffle so limiting the information below the crossover point is important. This crossover with its steep slopes would be more expensive to implement using analogue components, this is an excellent example of a manufacturer using DSP as a less expensive and more consistent alternative to analogue rather than using the DSP to perform tasks not possible in the analogue domain.

Mounting Options

With the FX80s I also received a pair of Fluid Audio’s DS8 Studio Monitor Stands. These were a surprise as they are far better in every way than I expected. A pair of contoured MDF panels with a choice of semi-rigid plastic legs and some self-adhesive rubber feet of different thicknesses allowing varying degrees of tilt, these stands not only raise the monitors to an appropriate height but also noticeably improve the sound compared to using the monitors directly on a tabletop, as I suspect many prospective users would use them. Considering their low price and the aforementioned low price of the FX80s, I’d call them a compulsory purchase for any buyer who doesn’t already have a decent set of speaker stands. They are $70!

If you are looking to wall mount them there are a pair of threaded inserts on the back panel, plugged with rubber bungs. Given their size and particularly their depth they wouldn’t be my first choice for a multichannel set up. I wait with interest to check out the FX50s as their smaller size might make them more suitable for a surround install, particularly when it comes to height channels in an Atmos setup?

Sound

I’m just coming the the end of a few weeks with a pair of the sublime Genelec 8331 “The Ones” 3 way coaxial monitors. To compare a pair of inexpensive monitors like the FX80s with a pair of monitors worth approximately 8 times as much wouldn’t be fair. I did it anyway but it definitely wouldn’t be fair…

The sound from the FX80’s is far, far better than it has any right to be. The top end is sweet, the bass ample and the imaging is really pin sharp. Level wise I found they could deliver monitoring as loud as I ever need for a near field position without losing composure. The depth of bass is enjoyable and the word which comes to mind is “clarity”, with an uncluttered sound which was really very pleasant to listen to. I was surprised by the specs when these monitors reported useful output below 40Hz. Putting on one of my standard test tracks for LF cutoff “Protection” by Massive Attack I found that the 50Hz sub under the kick is comfortably reproduced, extending this downward to Jamaroquai’s “Hot Property” the bottom of the synth line, which goes all the way down, was getting lost.

The word “uncluttered” is always a warning sign for me when appraising a new monitor because when I want to remove “clutter” from a mix I’ll typically look to lighten the mids. How were the FX80s through the midrange? This is where my completely unfair comparison with the 8331s comes in and I set up both monitors for an AB comparison. The results were very revealing. The 8331 is very flat through the mids and by comparison the FX 80s were a little scooped something possibly accentuated by some colouration in the low mids but honestly not all that much. To give some perspective here I also ran them up against my ageing Genelec 1029a’s. The FX80s sounded better in every way. Considering how much a pair of 1029a’s would have cost you new compared to these FX80s really shows how far we’ve come. I found that by changing the dip switches on the back to push the mids up by 1dB things were improved. They have a voice but they put in a perfectly respectable performance. I mixed on these without issue and the results stood up against mixes done on my regular monitors.

The other thing which drew my ear was a tendency to overhang a little in the bass. This isn’t uncommon in ported designs and my regular monitors are Neumann KH310s which I value particularly for their tight, dry bass courtesy of their sealed box design. It’s not by any means bad but the timing is a little loose, something I’m probably a bit too preoccupied with in my monitoring.

I should at this point revisit my praise of the DS8 monitor stands as I found the colouration issues to be enormously improved by introducing these stands. If you don’t already have “proper” stands these are a must.

Conclusion

These monitors are a perfect reminder of the enormous improvements which have been made in budget-conscious monitoring in recent years. This is a hugely competitive area of the market and producers who only a few years ago would have been using small two way monitors with colours as bright as their accuracy was questionable (I won’t name names…) now have the choice of several extraordinarily good monitors. The fact that you could buy a surround system of FX80s for the price of one of the monitors I compared them to tells you something. As a first pair or as a B pair if you buy these monitors you’ll find a lot to like.

Pros

• Ridiculously good value

• Sound genuinely good

• Generous bass extension

Cons

• Bass overhang