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Fluid Audio FX50V2 Monitor Review

Rate this studio monitor:

  • 1. Poor (headless panther)

    Votes: 6 3.4%
  • 2. Not terrible (postman panther)

    Votes: 53 29.9%
  • 3. Fine (happy panther)

    Votes: 100 56.5%
  • 4. Great (golfing panther)

    Votes: 18 10.2%

  • Total voters
    177

amirm

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This is a review, detailed measurements, listening tests and EQ of version 2 of Fluid Audio FX50 DSP studio monitor/active speaker. It was sent to me by the company and costs US $149 each.
Fluid Audio FX50v2 Active Studio Monitor Speaker review.jpg

There is nothing visually that distinguishes the unit from the original FX50 I reviewed a while back. The change is in the tuning performed by the internal DSP. Back panel sports usual EQ switches and support for both balanced and unbalanced connections:
Fluid Audio FX50v2 Active Studio Monitor Speaker DSP Back panel review.jpg


Unit was tested with the configuration you see above.

Fluid FX50 V2 Speaker Measurements
Let's start with our family of frequency response measurements:
Fluid Audio FX50v2 Active Studio Monitor Speaker anechoic spinorama frequency response measure...png


If we visually smooth out the graph, we see a good attempt at neutral response with flat on-axis that is much better than the original version:
index.php


There is curious ringing going on in mid frequencies which we have to analyze subjectively with listening tests due to their closeness with each other. Good directivity due to use of coaxial driver means early window response and predicted in room response resemble on-axis:
Fluid Audio FX50v2 Active Studio Monitor Speaker anechoic early window frequency response meas...png


Fluid Audio FX50v2 Active Studio Monitor Speaker predicted in-room frequency response measurem...png


Forgot to note the deep (F10) extension to 50 Hz for such a small speaker.

I measured the port response and there is a cabinet resonance that shows up:
Fluid Audio FX50v2 Active Studio Monitor Speaker port frequency response measurement.png


We can see clear disturbance in our directivity plots:
Fluid Audio FX50v2 Active Studio Monitor Speaker horizontal directivity measurement.png

Fluid Audio FX50v2 Active Studio Monitor Speaker horizontal beam width measurement.png

Fluid Audio FX50v2 Active Studio Monitor Speaker vertical directivity measurement.png


For distortion measurements, I added 76 dBSPL:
Fluid Audio FX50v2 Active Studio Monitor Speaker THD Distortion percentage measurement.png


Fluid Audio FX50v2 Active Studio Monitor Speaker THD Distortion measurement.png

We see very comfortable response at 76 and 86 dB.

Here are the waterfall and step responses:
Fluid Audio FX50v2 Active Studio Monitor Speaker CSD Waterfall measurement.png

Fluid Audio FX50v2 Active Studio Monitor Speaker Step Response measurement.png


Fluid Audio FX50V2 Listening Tests and EQ
Testing was performed in near field (1 meter/3 to 4 foot distance). Out of box sound was surprisingly neutral. There was just a bit of mid frequency muddiness though which I dialed out using very weak filters corresponding with the ringing peaks and one valley (optimized by ear):
Fluid Audio FX50v2 Active Studio Monitor Speaker Equalization.png


The overall improvement was subtle and I am not sure in a controlled test, would survive as an improvement. I was able to enjoy a lot of my reference tracks using this setup, not wanting to stop!

I was impressed with how loud I was play. Turning the volume way up, only gradually increased distortion without any bottoming out, static, or other complaints. I say it was able to play twice as loud as I expected it to!
Sub-pass was played at lower level with some distortion which is way better than many bookshelf speakers.

Conclusions
I applaud Fluid Audio for fine tuning the response of the FX50 to produce a far more neutral response than the OG version. Price/performance is excellent with inclusion of DSP and active, bi-amp design. There is an acoustic (?) problem causing the ringing in response but is easily corrected or ignored.

Overall, I am going to recommend the Fluid Audio FX50V2 studio monitor. It is a great starter system for the desktop.

------------
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 Audio FX50V2 frequency response.zip
    60.5 KB · Views: 50
Yowza, that is some bad diffraction. I don't think I've seen anything quite like that in a while. I also don't think I've ever seen an on-axis response that so closely resembles filter ripple in a while...
 
Yowza, that is some bad diffraction. I don't think I've seen anything quite like that in a while. I also don't think I've ever seen an on-axis response that so closely resembles filter ripple in a while...
I mean, there's a circular tweeter waveguide (with sharp edges) floating in front of the woofer, some eccentricity is quite expected under these circumstances.

The stick-out tweeter basically eliminates any Doppler distortion so such a coax should be able to play as loud as a comparable regular 2-way (while e.g. the Tannoy Gold 5 is not exactly known for its level handling abilities), but it introduces a fair bit of diffraction in return. Pick your poison.

Maybe it can do done better than what we're seeing here? (Except for the port resonance which could use some stuffing to sort out.) I'd want to see what a larger oval waveguide (see e.g. Presonus Eris Pro series) can do. It does seem like diffraction is kind of hard to avoid. Incidentally, you virtually need DSP for such a speaker, or else you're never going to get the time alignment of both drivers right (and even that is only ever going to be 100% correct on-axis).

Whichever way you're looking at it, if you want "coax + good" a 3-way seems hard to get around. Or at the very least, a 2-way needs to be conventional but bigger than average.
 
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Whichever way you're looking at it, if you want "coax + good" a 3-way seems hard to get around. Or at the very least, a 2-way needs to be conventional but bigger than average.
Yep, and even the best big coax 2-ways have diffraction problems (see: Mofi Sourcepoints). Pretty much every 3 way coax design measures better.
 
Kali UNF is the same price (300/ pair) and measurements are much better.
Well, if we are going to compare apples and oranges, I would rather pit these against the multitude of inexpensive conventional 5" class monitors in this price range (e.g. JBL 305P MkII, ADAM T5V, KRK RP5 G5, Mackie MR524 and the like) - heck, Thomann has 8" M-Audio BX8 D3s and Swissonic A308s if you want big and loud. As good as the LP-UNFs are, a 4.5" has its limits.

Besides, people buying coaxes generally know that they want one. Unfortunately, the cheap ones generally cannot keep the promise that comes with the idea of coincident sound sources. At least the FX50s are better overall than the JBL 104s (though I imagine the "dog's breakfast factor" in the latter has a lot to do with unsuppressed woofer breakup modes due to a lack of a proper crossover).
 
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If I didn't know better, I'd say the thing had Afib. Still, for $300 pr, coaxial driver, it's own amps, and being able to play at 86 db down to around 60 hz, what's not to like.

Very nice review, Amir. You've made friends with every flat broke college student needing tunes for his dorm room with this one.
 
Hello folks.
Price/performance is excellent with inclusion of DSP and active, bi-amp design.
This is the most important part of this review.

Very nice review, Amir. You've made friends with every flat broke college student needing tunes for his dorm room with this one.
Exactly. Not all of us are capable/ready to give four figures to enjoy music. I was once a flat broke student and needed music exactly to forget how flat broke I was.

Cheers :)
 
Here is my take on the EQ.
Please report your findings, positive or negative!

For the score rational your journey starts here
Explanation for the sub score
The following EQs are “anechoic” EQs to get the speaker right before room integration.
If you able to implement these EQs you must add EQ at LF for room integration, that is usually not optional… see hints there.

The raw data with corrected ER and PIR:

Score no EQ: 2.1
With Sub: 4.7

Spinorama with no EQ:
  • Lots of aberrations
Fluid Audio FX50V2 No EQ Spinorama.png



Directivity:
Better stay at tweeter height and toe in to your liking.
Fluid Audio FX50V2 2D surface Directivity Contour Only Data.png


EQ design:
I have generated two EQs. The APO config files are attached.
  • The first one, labelled, LW is targeted at making the LW flat
  • The second, labelled Score, starts with the first one and adds the score as an optimization variable.
  • The EQs are designed in the context of regular stereo use i.e. domestic environment, no warranty is provided for a near field use in a studio environment although the LW might be better suited for this purpose.
Code:
Fluid Audio FX50V2 APO EQ LW 96000Hz
October082024-152107

Preamp: -2.60 dB

Filter 1: ON PK Fc 821.6 Hz Gain 3.28 dB Q 6.98
Filter 2: ON PK Fc 1386.2 Hz Gain 2.90 dB Q 5.64
Filter 3: ON PK Fc 1019.4 Hz Gain -3.05 dB Q 3.00
Filter 4: ON PK Fc 1624.5 Hz Gain -2.99 dB Q 4.38
Filter 5: ON PK Fc 2302.6 Hz Gain 3.06 dB Q 3.14
Filter 6: ON PK Fc 2834.3 Hz Gain -2.31 dB Q 6.59
Filter 7: ON PK Fc 4456.1 Hz Gain -1.95 dB Q 6.84
Filter 8: ON PK Fc 7871.7 Hz Gain -1.30 dB Q 5.08
Filter 9: ON PK Fc 16368.0 Hz Gain 3.33 dB Q 1.41
Filter 10: ON PK Fc 18204.0 Hz Gain -3.68 dB Q 4.48

Fluid Audio FX50V2 APO EQ Score 96000Hz
October082024-152107

Preamp: -2.20 dB

Filter 1: ON PK Fc 812.6 Hz Gain 4.53 dB Q 6.98
Filter 2: ON PK Fc 1336.0 Hz Gain 2.90 dB Q 5.01
Filter 3: ON PK Fc 995.6 Hz Gain -4.05 dB Q 1.71
Filter 4: ON PK Fc 1607.9 Hz Gain -2.99 dB Q 6.88
Filter 5: ON PK Fc 2307.6 Hz Gain 3.12 dB Q 3.14
Filter 6: ON PK Fc 2836.3 Hz Gain -2.31 dB Q 4.44
Filter 7: ON PK Fc 4518.1 Hz Gain -3.34 dB Q 4.84
Filter 8: ON PK Fc 7788.3 Hz Gain -1.96 dB Q 5.08
Filter 9: ON PK Fc 22294.3 Hz Gain 2.33 dB Q 3.41
Filter 10: ON PK Fc 18205.0 Hz Gain -3.18 dB Q 2.48

Fluid Audio FX50V2 EQ Design.png

Score EQ LW: 4.1
with sub: 6.7

Score EQ Score: 4.5
with sub: 7.1

Spinorama EQ LW
Fluid Audio FX50V2 LW EQ Spinorama.png

Spinorama EQ Score
Fluid Audio FX50V2 Score EQ Spinorama.png

Zoom PIR-LW-ON
Fluid Audio FX50V2 Zoom.png


Regression - Tonal
Fluid Audio FX50V2 Regression.png


Radar no EQ vs EQ score
Nice improvements?
Fluid Audio FX50V2 Radar.png








The rest of the plots is attached.
 

Attachments

  • Fluid Audio FX50V2 APO EQ Score 96000Hz.txt
    624 bytes · Views: 27
  • Fluid Audio FX50V2 APO EQ LW 96000Hz.txt
    622 bytes · Views: 20
  • Fluid Audio FX50V2 2D surface Directivity Contour Data.png
    Fluid Audio FX50V2 2D surface Directivity Contour Data.png
    245.6 KB · Views: 41
  • Fluid Audio FX50V2 3D surface Vertical Directivity Data.png
    Fluid Audio FX50V2 3D surface Vertical Directivity Data.png
    350.4 KB · Views: 37
  • Fluid Audio FX50V2 3D surface Horizontal Directivity Data.png
    Fluid Audio FX50V2 3D surface Horizontal Directivity Data.png
    349.7 KB · Views: 31
  • Fluid Audio FX50V2 Normalized Directivity data.png
    Fluid Audio FX50V2 Normalized Directivity data.png
    446.7 KB · Views: 33
  • Fluid Audio FX50V2 Raw Directivity data.png
    Fluid Audio FX50V2 Raw Directivity data.png
    587.3 KB · Views: 33
  • Fluid Audio FX50V2 Reflexion data.png
    Fluid Audio FX50V2 Reflexion data.png
    224 KB · Views: 35
  • Fluid Audio FX50V2 LW data.png
    Fluid Audio FX50V2 LW data.png
    201.8 KB · Views: 40
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Well, if we are going to compare apples and oranges, I would rather pit these against the multitude of inexpensive conventional 5" class monitors in this price range (e.g. JBL 305P MkII, ADAM T5V, KRK RP5 G5, Mackie MR524 and the like) - heck, Thomann has 8" M-Audio BX8 D3s and Swissonic A308s if you want big and loud. As good as the LP-UNFs are, a 4.5" has its limits.

Besides, people buying coaxes generally know that they want one. Unfortunately, the cheap ones generally cannot keep the promise that comes with the idea of coincident sound sources. At least the FX50s are better overall than the JBL 104s (though I imagine the "dog's breakfast factor" in the latter has a lot to do with unsuppressed woofer breakup modes due to a lack of a proper crossover).
The T5V rolls this in terms of neutrality, especially if you add a little shelf filter. Don't know what the difference is in terms of SPL, I know from experience the T5V is pretty limited unless you use the sub to offload a lot of the low frequency.
 
Hello,

Fluid improved a bit but just a bit from the previous generation.
newplot (1).png


I am not sure there is something to fix, the sharp peaks/dips are not that audible. How good/bad it is in practice IDK and without a specimen to listen to it is hard to tell.
Possibly some simple eq could help:
Code:
EQ for Fluid Audio FX50v2 computed from ASR data
Preference Score 2.11 with EQ 3.22
Generated from http://github.com/pierreaubert/spinorama/generate_peqs.py v0.26
Dated: 2024-10-09-17:03:03

Preamp: -3.7 dB
Filter  1: ON PK Fc    52 Hz Gain +2.98 dB Q 2.67
Filter  2: ON PK Fc   121 Hz Gain +2.88 dB Q 0.58
Filter  3: ON PK Fc   125 Hz Gain -3.35 dB Q 1.11
Filter  4: ON PK Fc   910 Hz Gain +3.00 dB Q 1.37
Filter  5: ON PK Fc  1010 Hz Gain -5.93 dB Q 2.99

filters_eq.jpg


Maybe what @Maiky76 proposed works better, YMMV.
 
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Score no EQ: 2.1
I expected the score to go up, not down relative to original version. These small variations are not nearly as audible as the large dip in the original.
 
Thank you for your review and measurements Amir. :)

_____
Well, if we are going to compare apples and oranges, I would rather pit these against the multitude of inexpensive conventional 5" class monitors in this price range (e.g. JBL 305P MkII, ADAM T5V, KRK RP5 G5, Mackie MR524 and the like) - heck, Thomann has 8" M-Audio BX8 D3s and Swissonic A308s if you want big and loud. As good as the LP-UNFs are, a 4.5" has its limits.

Besides, people buying coaxes generally know that they want one. Unfortunately, the cheap ones generally cannot keep the promise that comes with the idea of coincident sound sources. At least the FX50s are better overall than the JBL 104s (though I imagine the "dog's breakfast factor" in the latter has a lot to do with unsuppressed woofer breakup modes due to a lack of a proper crossover).
The Fluid Audio FX50V2 monitor speakers may not be considered top notch high end coax speakers, but the price of them, on the other hand, is not that high.
That said, as you point out, there is a lot of competition in that price range.

Don't you think the Fluid Audio FX50V2 monitor fills a market gap for those who want a pair of cheap small coax speakers for near field listening?

If we are talking about extreme near field, close listening.Shouldn't a coax speaker vs for example a non-coax two-way speakers give better opportunities (theoretically, as a design principle), for better sound the closer the listener is placed to the speakers? Shouldn't sound from a point source be preferred then?

OT. Extremely close listening to speakers has never really been my thing. Then I think you might as well wear headphones. :)
 
Interesting way to get started with some passible sound for an introductory price. I’m wondering if they have a larger version and if it’s slightly improved (i.e., measures better)?

Thanks Amir, as always!
 
Eh... Wouldn't pass muster in my listening area.
 
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