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Fluid Audio FX50 Review (Active Speaker)

amirm

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This is a review and detailed measurements of the Fluid Audio FX50 powered monitor. It costs US $149 each from Amazon including Prime shipping. I purchased my sample a few months ago on sale but then the company contacted me and said they have had some updates to the tuning of the speaker and sent me another sample. This review is done with this latter sample, not my own.

The FX50 is kind of cute in its smaller than usual enclosure:

Fluid FX50 Review Powered Monitor Speaker.jpg


As you see, it uses old school coaxial configuration of tweeter inside the woofer (Altec Lansing style?).

Back side shows the controls which are managed using DSP and bi-amping:

Fluid FX50 Review DSP Powered Monitor Speaker.jpg


I left all the controls off/as you see them both for measurements and listening tests.

Measurements that you are about to see were performed using the Klippel Near-field Scanner (NFS). This is a robotic measurement system that analyzes the speaker all around and is able (using advanced mathematics and dual scan) to subtract room reflections (so where I measure it doesn't matter). It also measures the speaker at close distance ("near-field") which sharply reduces the impact of room noise. Both of these factors enable testing in ordinary rooms yet results that can be more accurate than an anechoic chamber. In a nutshell, the measurements show the actual sound coming out of the speaker independent of the room.

I performed over 1000 measurement which resulted in error rate of around 1%.

Temperature was 61 degrees F at sea level. I kept the speaker indoor at 70 degrees prior to starting the measurements.

Measurements are compliant with latest speaker research into what can predict the speaker preference and is standardized in CEA/CTA-2034 ANSI specifications. Likewise listening tests are performed per research that shows mono listening is much more revealing of differences between speakers than stereo or multichannel.

Reference axis was the tweeter center.

Fluid F50 Measurements
Acoustic measurements can be grouped in a way that can be perceptually analyzed to determine how good a speaker is and how it can be used in a room. This so called spinorama shows us just about everything we need to know about the speaker with respect to tonality and some flaws:

Fluid FX50 Measurements Frequency Response Spinorama CTA-2034 Powered Monitor Speaker.png


At first on-axis response looks pretty messy. But a lot of the variations are narrowly spaced so they are not going to be as audible as they seem to the eye. There is a pronounced dip however that will be audible between 2 and 3 kHz, taking a bit of life/sparkle out of the music. Due to coaxial nature, off-axis response follows on-axis:

Fluid FX50 Measurements early window Frequency Response Spinorama CTA-2034 Powered Monitor Spe...png

Fluid FX50 Measurements Predicted In-room PIR Frequency Response Spinorama CTA-2034 Powered Mo...png


One of the peaks is caused by the very common port resonance:

Fluid FX50 Measurements near-field response.png


Beamwidth is controlled of course due to same coaxial nature but frequency response variations make it look messy:

Fluid FX50 Measurements horizontal beam width.png

Fluid FX50 Measurements horizontal diretivity.png


Fluid FX50 Measurements vertical diretivity.png


Waterfall graph shows a lot of low frequency resonances including the one from the port:

Fluid FX50 Measurements CSD waterfall.png


Edit: forgot the distortion graphs originally:

Fluid FX50 Measurements distortion relative.png


Fluid FX50 Measurements distortion THD.png

Fluid FX50 Speaker Listening Tests
Let me address hiss first: there is some and it is rather high in frequency. I can't hear it past a foot of so.

I went into my evaluations expecting the sound to not be very good but I was surprised. That boosted bass response is quite pleasant and provides fair bit of balance to the rest of the spectrum. I did want to fix the EQ and port resonance however:

Fluid FX50 Equalization  Powered Monitor Speaker.png


Once there, I thought the sound was a bit bright so dialed in the high frequency shelf. You may or may not want to have that in there depending on your preference.

At this pint I thought the sound was less boomy and very enjoyable. Yes, deep bass at any reasonable level would cause static and audible distortion. A high pass filter did not fix that and just took away some useful bass so I left it out (Band 1 above). I was listening with one speaker but if you have two speakers, this will be less of a problem.

Conclusions
Objectively the FX50 has some flaws that we can clearly see in the measurements. But what bothers the eye sometimes is much less of an issue for the ear. Such seems to be the case here. With a bit of an EQ, the tonality is both inviting and very good. A speaker engineer once emailed me to say while he is a fan of my measurements and work, he is unhappy that I don't take into account that a budget speaker is going to have many compromises. I think in this case, the compromises are acceptable in my book as the subjective results are very nice.

So overall, I am going to give the FX50 a recommendation. It is one of the few compact budget speakers that sounds good.

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As always, questions, comments, recommendations, etc. are welcome.

Appreciate any donations using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 

Attachments

  • Fluid FX50 Spinorama Frequency Response.zip
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Curious to see distortion graphs if you've got them Amir. Overall this looks okay, but really nothing special.
 
Curious to see distortion graphs if you've got them Amir. Overall this looks okay, but really nothing special.
Oops. Sorry, forgot to include them. Added to the review.
 
The measurements don't look too good, nowhere near as good as the similarly priced T5V. But then again, we have seen way worse performance for way more money.

I think these reviews of (budget) studio monitors are among the most interesting ones here. They sell in large numbers and there are meaningful differences between them, plus for most of them it is all but impossible to find reliable measurements anywhere else.
 
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I purchased my sample a few months ago on sale but then the company contacted me and said they have had some updates to the tuning of the speaker and sent me another sample.
are they selling it under the same product name/version? if newer one is better this seems unfair. to be clear, I'm not against updates, but if they made a better version they should be selling it as V2 or something like that.

It would be interesting to see how the version you bought compares.
 
This is an interesting case. I think this may be one of those speakers where what we actually hear might be a bit more like the smoothed graph. Yes, the spin is very jagged, but other than the dip at 2.5kHz, the trends are pretty good, and the vertical directivity (which isn't perfect either) may make up for some of the flaws. I do wonder whether that off-axis peaking at 4kHz may become an issue in reflective rooms though.

Not too bad for the price, personally. But yes, there are better options for the price as well.
 
There should be an ASR measured hiss chart, as this is significant for active speakers.

Uneven response, high port noise, better options in the price range... Panther was kind today.
 
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These seem like a pretty good option for travel speakers or for a small office. Other speakers in this price range perform better but the ones tested have been much larger (Edit: or much more expensive)

Distortion seems pretty good for a nearfield monitor that would be placed a couple feet from your ears. I've been looking for a pair of speakers to bring with me when i'm traveling for work and these look really promising. Here's hoping that the smaller ilouds get tested.
 
plus for most of them it is all but impossible to find reliable measurements anywhere else.
Agree with that and this the most. Most budget speaker makers are too chicken to publish inevitably poor measurements that don't tell consumers much in comparison to their competitors' similarly poor measurements. So ya, ASR is a big asset here.
 
Most budget speaker makers are too chicken to publish inevitably poor measurements
I don't know about that, compared to passive speakers from many established brands, these active monitors are actually pretty competitive in price and performance, some more than others of course.
Genelec and Neumann offer near state of the art performance at round the 1000€/pair price point.

I would also love to see studio subs measured. For the cheaper (<400€) ones the manufacturers don't publish measurements. Is there anyone doing that already?
 
Really interesting. I was going ask at some point if you wanted to test these because they are so inexpensive.

I am really focused on coaxial designs right now (in terms of my curiosity levels).

I really want to see the new Tannoy Gold series tested. Is there one up to bat?

@amirm stated"A speaker engineer once emailed me to say while he is a fan of my measurements and work, he is unhappy that I don't take into account that a budget speaker is going to have many compromises. I think in this case, the compromises are acceptable in my book as the subjective results are very nice. "

IMHO I really don't think you have been to hard on the budget speakers tested here. I do feel you accommodate the price pretty well. THE FACT IS ! -There have been far more successful budget designs tested here than I ever anticipated in fact. & it has been made very clear that using PEQ/DSP type Corrections, with many budget/mid-fi priced speakers gets you into EXCELLLENT territory.
I actually use this site to demonstrate to folks that budget gear has come a long, long, long, long way.
 
Here's another pic of the tweeter assembly showing it is mounted in front of the woofer. The front view of the speaker makes the tweeter appear as if recessed inside the woofer. I was wondering how Fluid Audio could afford to put a tweeter inside the woofer assembly and now it make sense how they budgeted the design.
d_fx50-angeld-r_2.png
 
I don't know about that, compared to passive speakers from many established brands, these active monitors are actually pretty competitive in price and performance, some more than others of course.
Genelec and Neumann offer near state of the art performance at round the 1000€/pair price point.

I would also love to see studio subs measured. For the cheaper (<400€) ones the manufacturers don't publish measurements. Is there anyone doing that already?
A preference score of 2.9 makes these monitors pretty average for their price range in comparison to other active speakers in it, let alone competitve with established passive speakers. Not sure where you mean the measurements are competitive, from an objective standpoint. Distortion is better than average for budget active speakers for sure, though.
Ya, more studio subs would be handy. It's especially nice to know differences in distortion, since most subs have decent enough fr after a certain price.
 
A preference score of 2.9 makes these monitors pretty average for their price range in comparison to other active speakers in it, let alone competitve with established passive speakers. Not sure where you mean the measurements are competitive, from an objective standpoint. Distortion is better than average for budget active speakers for sure, though.
Ya, more studio subs would be handy. It's especially nice to know differences in distortion, since most subs have decent enough fr after a certain price.
With harmonic distortion you can predict the improvement.
All frequecies that are affected by the high-pass crossover will have lowered distortion.
All frequencies above the crossover will laregely have the exact same harmonic distortion levels wity no meaningfull change.
All my measurements thus far bear this out.
So drivers with high levels of HD above your selected crossover frequency will still have such issues.
Intermodular distortion will very likely be reduced above the crossover due to less excursion of the woofer and less heat in the voice coil but we dont yet have those measurements and each driver reacts very differently.
 
Decent for the price. These might find there way into some budget desktop setups. Thank you @amirm
 
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