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:
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:
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:
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:
One of the peaks is caused by the very common port resonance:
Beamwidth is controlled of course due to same coaxial nature but frequency response variations make it look messy:
Waterfall graph shows a lot of low frequency resonances including the one from the port:
Edit: forgot the distortion graphs originally:
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:
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.
------------
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/
The FX50 is kind of cute in its smaller than usual enclosure:
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:
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:
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:
One of the peaks is caused by the very common port resonance:
Beamwidth is controlled of course due to same coaxial nature but frequency response variations make it look messy:
Waterfall graph shows a lot of low frequency resonances including the one from the port:
Edit: forgot the distortion graphs originally:
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:
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.
------------
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/
Last edited:
..
