In this article, we try the FX50 from Fluid Audio. Is it the answer for those seeking an affordable way into Dolby Atmos monitoring?

Fluid Audio has been on something of a roll recently, their FX range 2-way coaxial monitors have offered something genuinely new in terms of price vs performance in this already super-competitive area of the market.

Very inexpensive active monitors have been available for many years but their performance was usually couched in terms of ‘for the money’. The first product which convinced me that extremely cheap monitors could ever be more than a stop-gap on the way to a set of “proper monitors” were the JBL306P MkII, a 2-way design with a striking and very effective waveguide around the tweeter. The same team were responsible for the Kali LP6, which took the concept of the 306P and turned it into a class leader. With extremely competent products like these, which deliver genuinely good results on razor-thin margins, what could a company like Fluid Audio bring to this sector of the market?

The answer is a different approach. The 5-6” bass/mid driver 2-way design does appear to be something of a sweet spot in terms of price vs performance and that is exactly what is on offer here with the FX50 but in a very different package compared to the JBL/Kali approach.

Besides the price, $149 per monitor (Yes that does say $149 per monitor!) the two headlines here are coaxial drivers and DSP. The DSP isn’t the kind of clever system which will calibrate your monitors to your room, it implements conventional crossover filters using DSP rather than analogue components and as such it is transparent to the user. It is a wise choice in a design like this one where the unusual crossover is carefully matched to the physical arrangement of the drivers but unless you read the specs you wouldn’t be aware that the monitor wasn’t all analogue.

What isn’t as easily missed is the coaxial driver, which uses a clever arrangement of a tweeter and bass/mid driver. Rather than being mounted in such a way that the driver cone of the bass/mid driver acts as the waveguide, the FX50 mounts the HF driver on a rigid mounting with a separate waveguide in front of the woofer, thereby avoiding the potential for doppler shift issues caused by interactions between the HF and mid/bass drivers. For a more detailed explanation of this arrangement, as well as more detail on why the crossover slopes are steeper than is typical in this design see our article talking a detailed look at the FX50’s bigger sibling the FX80.

How Is The FX50 different From The FX80?

Both share very similar construction, cabinets and porting, differing only in size. The rear panels offer the same controls and connections. There are so many similarities between the FX80 and the FX50 that it makes more sense to highlight the differences than to repeat the details of the similarities between these two models. They all are a consequence of the smaller design, the design goals are after all identical - Make as good a 2-way monitor as possible for as little money as possible.

The woofers are obviously different, the 8” paper composite cone being replaced by a 5” driver of similar construction. Without looking closely the HF drivers look the same but the FX80 has a 1.2” soft dome driver and the FX50 has a 1” driver. The crossover points are 2.4KHz and 2.9KHz respectively. The frequency response extends down to a quoted 35Hz (-3dB) for the 80 compared to 49Hz (-3dB) for the 50. The class D amplifiers are reduced in power by 10W each in the FX50 compared to the FX80 (50w LF, 40w HF). So what we have here is a very similar approach but the two models share few common components.

Who Should Buy The FX50 Over The FX80?

The FX80 performs extremely well and couldn’t be accused of being expensive, so what then is the point of the 50? The 80 has more bass, the difference between 35 and 49Hz might be less than a fifth in musical note terms but those are some really important notes. Of course, if you can’t afford the 80 then the 50 is a very respectable alternative but aren’t there more reasons to be interested in this monitor?

People with restricted budgets looking for a first pair of monitors are of course an extremely important market and the FX50 is an ideal candidate for those customers, they would also make an excellent B pair for someone with another set of monitors already installed. Anyone who has ever set up multiple pairs of monitors in a typical nearfield application will know how little room there is to install monitors at anything like the ideal equilateral triangle spacing, particularly if you are working less than a meter and a half away from your monitors. Size really matters in some applications and by that I mean a lack of size is often very desirable.

This brings me to a third and I think possibly very significant group of customers who might find the FX50 very attractive - those migrating to Dolby Atmos.

If you are lucky enough to already have a quality 5.1 or 7.1 system installed then the additional costs of adding four height channels, two is possible but not recommended, aren’t small but aren’t too daunting. This would cover many post-production users. For example, Mike Thornton has extended his PMC monitoring to full Dolby Atmos by adding to his existing surround monitoring. It wasn’t exactly cheap, but buying secondhand did soften the hit on his wallet and made it affordable.

Unlike standard surround formats, Dolby Atmos has been gaining traction in music and support from Apple and other streaming platforms has made a lot of music mixers sit up and pay attention. The jump from stereo to Dolby Atmos is huge and while the software and hardware resources necessary aren’t enormous, the costs of adding up to 11 new monitors to install a Dolby Atmos monitoring system can quickly get too big to justify.

My monitors are approximately £1500 each. To simply add a suitable sub and another 9 monitors of the same model would cost £15K, just in speakers. For the overwhelming majority of music mixers, there is no compelling business reason to go to Atmos. So there is a whole group of experienced mixers who are looking with great interest at inexpensive monitors which perform well.

This brings me to the other consequence of shrinking the FX80 to the FX50. The speaker itself is pretty compact, something which can’t be said of the FX80. At approximately 9”x7”x9” (HxWxD) compared to the 13.5”x10”x11.5” of the FX80 the FX50 makes a more install-friendly option for the compact mix room it might well find itself in. The depth is particularly important in this regard as if installed on an appropriate bracket (both the FX50 and FX80 feature threaded brass inserts on the rear panel making their installation as height channels far easier) a deep cabinet is unhelpful, particularly with the low ceilings common to many project studios. Being coaxial means that speakers can be mounted on their sides, upside down, whatever is necessary, always a bonus when fitting speakers into restricted spaces.

Being able to create a 7.1.4 monitoring system for 10% of the cost of a system using my current monitors has absolutely got my attention. You read that right, you can buy 10 FX50s for the cost of one of my current monitors. I’m aware that isn’t comparing like with like but I really want to explore Dolby Atmos and I don’t want to have to do it using headphones and binaural fold downs. But I’m not going to spend £15K to satisfy my curiosity about Atmos workflows!

Performance

Of course you get what you pay for and a system built from my current monitors would be a beautiful thing, but how do these FX50s sound and would I find the results good enough to work on in an Atmos workflow?

If you haven’t yet looked at the FX80 article I suggest you do as most of what is said there is also true of these. Actually what really matters here is the sound they don’t produce rather than the sound that they do. The difference between 35Hz and 49Hz is significant and I won’t deny that the bass is a little light compared to the ample low frequency available with the FX80. Although the respective Max SPL of each is 104dB SPL @1m for the FX80 and 101dBSPL for the FX 50. I found that running the smaller FX50s in stereo I was occasionally pushing them out of their comfort zone, something I didn’t find with the FX80s in the same way.

Do the FX50s sound good? With the caveats mentioned above, absolutely yes and the value they represent is frankly unbelievable. Would I buy some? For stereo use I’m not their customer but I am a stereo-only music mixer who is “Atmos-curious” and I have recently run in four sets of power and audio cables to points over my mix position for height channels so I must be getting close to buying a ton of monitor speakers. Will those speakers be FX50s? I suspect they will, but perhaps not all of them. An FX50 costs $149, an FX80 costs $249. I suspect if I do push the button on an inexpensive Atmos system I’d use FX80s across the front and FX50s for the rears and height channels. That would be an amazing value system I’d love to hear.

Pros

• So inexpensive

• Good Sound

• Compact

• Install friendly

Cons

• With the added compactness comes an inevitable reduction in deep bass.