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M-Audio BX8 D3 Monitor Review

Rate this studio monitor

  • 1. Poor (headless panther)

    Votes: 7 4.1%
  • 2. Not terrible (postman panther)

    Votes: 38 22.1%
  • 3. Fine (happy panther)

    Votes: 110 64.0%
  • 4. Great (golfing panther)

    Votes: 17 9.9%

  • Total voters
    172

amirm

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This is a review, listening tests and detailed measurements of the M-Audio BX8 D3 studio reference (active speaker). I purchased it new from Amazon June of last year for $503. It seems discontinued now.
M-Audio BX8 D3 Studio Monitor Speaker Active Review.jpg

Look and feel is excellent. There is rubberized paint around the drivers which gives the unit a luxury feel. The cabinet is quite large and sturdy. Back panel is simplicity in itself:
M-Audio BX8 D3 Studio Monitor Speaker Active back panel XLR Review.jpg


Amplification is class AB (80 watts for woofer, 70 watts for tweeter) which is surprising. Good news is that this brings silence to the tweeter as I could barely hear a hiss with my ear next to it.

Nicely formed waveguides should produce good directivity.

Testing was performed using Klippel Near-field Scanner (NFS). Temperature was around 57 degrees F. Reference axis was the center of the tweeter.

M-Audio BX8D3 Measurements
As usual, we start with our anechoic frequency responses per CEA-2034/ANSI standard:
M-Audio BX8 D3 Studio Monitor Speaker Frequency Response Measurements.png


That sudden resonance at 590 Hz stands out well in addition to somewhat wavy response above it. On the positive front, bass extension is quite good especially given the size and cost of this speaker. There is usable bass down to some 40 Hz! Near-field measurements show that the kink at 590 Hz is the property of the woofer:
M-Audio BX8 D3 Studio Monitor Speaker near field Frequency Response Measurements.png


I expected it to be port resonances but those are quite subdued until you get to about 1 kHz. If someone has a better guess, please chime in.

Early reflections and predicted in-room simulations are for far field use so likely not very applicable in this application:
M-Audio BX8 D3 Studio Monitor Speaker early reflection Frequency Response Measurements.png


M-Audio BX8 D3 Studio Monitor Speaker PIR Frequency Response Measurements.png


I was very impressed with the low distortion, especially in bass at 86 dBSPL:
M-Audio BX8 D3 Studio Monitor Speaker THD Distortion Measurements.png

M-Audio BX8 D3 Studio Monitor Speaker Relative THD Distortion Measurements.png



As predicted, directivity and hence beamwidth uniformity is very good in horizontal axis:
M-Audio BX8 D3 Studio Monitor Speaker Horizontal Beamwidth Measurements.png

M-Audio BX8 D3 Studio Monitor Speaker Horizontal directivity Measurements.png


Vertical suffers from typical issues with 2-way speakers but there seems to be good control even in that axis:
M-Audio BX8 D3 Studio Monitor Speaker Vertical directivity Measurements.png


Here is our waterfall and step responses:
M-Audio BX8 D3 Studio Monitor Speaker CSD Waterfall Response Measurements.png


M-Audio BX8 D3 Studio Monitor Speaker Step Response Measurements.png


M-Audio BX8 D3 Listening Tests
The uneven frequency response had pre-biased me negatively going into the listening tests. But 5 seconds of listening to my standard test tracks changed my mind and quickly! That deep bass and clean output at that, brings a ton to the table. Speaker sounds like a much bigger one. Frankly I could have lived with the out of box response but still, took a shot at correcting the response with EQ:

M-Audio BX8 D3 Studio Monitor Speaker Equalization.png


The correction for the bass resonance should be self-explanatory. I then attempted to fill in the gap between 1 and 2 kHz but that resulted in extra brightness. Instead, I opted to pull down the hills in the next two regions. With all the filters in place, the difference was small but I thought it was more balanced and less brilliant/brittle.

The excellent bass response translated to my "speaker killer" tracks with sub-bass response down to 20 Hz. Many bookshelf speakers fall apart and produce distorted sound there (or none at all). The BX8D3 was different. It simply played those at lower volume but still clean. No doubt this contributed to my impression of the speaker sounding so clean.

While listening to only one speaker, I could easily fill my massive space with plenty of volume withy nary a hint of distortion or speaker/amp funning out of breath. The sound had authority and was quite enjoyable.

Conclusions
I was pretty depressed going into this review with first finding out the BX8 D3 is now discontinued. And then seeing response anomalies. Then I listened to the speaker and that changed my perspective. Not that the subjective impression was different from objective. It was not. You just had to go back and look again, noticing the bass extension and very low distortion. Research shows that 1/3 of our impression of a speaker sound comes from bass and boy was that true in this case. With a bit of EQ you have one impressive sounding studio monitor here which would be good at $500 but far better at the discount prices I see on clearance (as low as $118 on one site!!!).

Note that the extra bass means is that the BX8D3 will charge the room modes so you better have EQ especially if your room is small. Other monitors in its size which lack bass won't be similarly situated.

I am going to put the M-Audio BX8D3 on my recommended list. It is a shame that it is discontinued.

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

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 

Attachments

  • M-Audio BX8 D3 Frequency Response.zip
    61.4 KB · Views: 169
By the way, there are a number of "BX8" speakers for sale out there but seem to be another series with round waveguide rather than the square one in the model I tested.
 
Here is my take on the EQ.
Please report your findings, positive or negative!

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: https://www.audiosciencereview.com/...helf-speaker-review.11144/page-26#post-800725

The raw data with corrected ER and PIR:

Score no EQ: 5.2
With Sub: 7.2

Spinorama with no EQ:
  • LF Driver issue too bad...
  • Decent design buried some under tuning idiosyncrasies
  • Decent directivity will help for effective EQ
M-Audio BX8 D3 No EQ Spinorama.png


Directivity:
Better stay at tweeter height
Horizontally, better toe-in the speakers by 10/20deg and have the axis crossing in front of the listening location, might help dosing the upper range.
M-Audio BX8 D3 LW data.png
M-Audio BX8 D3 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.

Score EQ LW: 5.8
with sub: 7.8

Score EQ Score: 6.1
with sub: 8.2

Code:
M-Audio BX8 D3 APO EQ LW 96000Hz
April142023-124610

Preamp: -2.8 dB

Filter 1: ON PK Fc 64.51,    -1.53,    3.27
Filter 2: ON PK Fc 117.71,    -1.47,    1.55
Filter 3: ON PK Fc 645.12,    -3.11,    4.13
Filter 4: ON PK Fc 922.00,    -1.55,    2.14
Filter 5: ON PK Fc 1799.79,    2.50,    0.82
Filter 6: ON PK Fc 2979.36,    -1.86,    4.75
Filter 7: ON PK Fc 12256.79,    2.94,    0.55
Filter 8: ON PK Fc 9514.76,    -1.80,    4.14

M-Audio BX8 D3 APO EQ Score 96000Hz
April142023-124611

Preamp: -2.7 dB

Filter 1: ON PK Fc 63.50,    -1.48,    4.13
Filter 2: ON PK Fc 117.21,    -1.51,    1.21
Filter 3: ON PK Fc 625.78,    -2.90,    4.98
Filter 4: ON PK Fc 932.00,    -2.00,    1.81
Filter 5: ON PK Fc 1665.60,    2.96,    1.14
Filter 6: ON PK Fc 2929.12,    -1.46,    5.00
Filter 7: ON PK Fc 12251.29,    2.18,    0.71
Filter 8: ON PK Fc 9511.76,    -1.65,    3.17
M-Audio BX8 D3 EQ Design.png

Spinorama EQ LW
M-Audio BX8 D3 LW EQ Spinorama.png

Spinorama EQ Score
M-Audio BX8 D3 Score EQ Spinorama.png

Zoom PIR-LW-ON
M-Audio BX8 D3 Zoom.png

Regression - Tonal
M-Audio BX8 D3 Regression.png

Radar no EQ vs EQ score
some improvements
M-Audio BX8 D3 Radar.png


The rest of the plots is attached.
 

Attachments

  • M-Audio BX8 D3 APO EQ Score 96000Hz.txt
    435 bytes · Views: 99
  • M-Audio BX8 D3 APO EQ LW 96000Hz.txt
    432 bytes · Views: 100
  • M-Audio BX8 D3 2D surface Directivity Contour Data.png
    M-Audio BX8 D3 2D surface Directivity Contour Data.png
    273.1 KB · Views: 80
  • M-Audio BX8 D3 3D surface Vertical Directivity Data.png
    M-Audio BX8 D3 3D surface Vertical Directivity Data.png
    469.5 KB · Views: 70
  • M-Audio BX8 D3 3D surface Horizontal Directivity Data.png
    M-Audio BX8 D3 3D surface Horizontal Directivity Data.png
    459.8 KB · Views: 75
  • M-Audio BX8 D3 Normalized Directivity data.png
    M-Audio BX8 D3 Normalized Directivity data.png
    324.3 KB · Views: 72
  • M-Audio BX8 D3 Raw Directivity data.png
    M-Audio BX8 D3 Raw Directivity data.png
    483.2 KB · Views: 104
  • M-Audio BX8 D3 Reflexion data.png
    M-Audio BX8 D3 Reflexion data.png
    146.6 KB · Views: 83
Last edited:
Agreed. The FR is kind of chewed up, looks like the bass extension was the saving grace.
 
Not too bad for 129€/piece, would have expected worse from the cheapest of the 8“ monitor crowd.
I would see this more as something cheap for casual listening rather than a serious monitor. They‘re fine without a sub for TV sound or something like that.
 
yeah i think these are cheaper outside of the US strangely enough

in US its like $500 us for a single unit??? $1,000 for 2? at that price the competition is too stiff

where I am we can easily find a pair for $500 aud which is about $350 usd and we also have 10% sales tax here

at 129 euros its a no brainer

where else can you get a set of 8" powered for 260 euro?

my thinking is that the distributors here bought too many 8" units and few people want 8" units in their face (so to speak!)

they can easily sell 4-5-6" and so they have to discount 8" speakers

again, none of this is acceptable at $1,000 usd but for $260 euro? its this or simon and garfunkel's the sound of silence


btw. here's a pic of round tweeter version:


i feel like they substitutes parts but dont bother to change any specs sheets because... audience doesnt care
 
Personally, I’d rather not have this playing below 600 or 700 Hz. And 6KHz to 10 KHz is not stellar. The off-axis behavior is reasonable. I wouldn’t want to pay list. Too many better alternatives. At ca.$120 it’s best to grab it fast. Give it to the kids. With a sub that plays to 500Hz.
 
Not great performance especially if it costed $500, but for later prices around hundred something acceptable as due to its decent directivity behaviour it can be improved via equalisation.
 
i sort of feel like that defeats the purpose of an 8" woofer. if you're gonna cut at 500hz then get a smaller speaker?
 
590hz resonance is probably internal box wall reflection. More acoustic damping material would probably take care of it.
Yeh, looking through the port I can't see any stuffing....
 
They probably sound much better than my Edifier S3000 Pro. Maybe buy a pair out of curiosity?
What sound source would be solid and sufficient for such speakers?
 
Last edited:
Thanks amir for the review
At 129 euro from a reputable store this is quite a bargain since it takes well to EQ. Some competition for the JBL with more bass and a different overall response

Good to have options xD
 
Last edited:
I built an EQ for this speaker. Preference score goes from 5.2 to 6.1 with EQ and from 7.2 to 8.0 with EQ and a perfect subwoofer.
PIR and LW get significantly flatter. The EQ is limited to Q<3 and does track relatively well but miss a few peaks. I expect this speakers
to have high variability unit to unit so it doesn't really matter. Histograms are useful to see improvements both full range and on the midrange.

Code:
EQ for M-Audio BX8 D3 computed from ASR data
Preference Score 5.25 with EQ 6.11
Generated from http://github.com/pierreaubert/spinorama/generate_peqs.py v0.21
Dated: 2023-04-14-09:11:46

Preamp: -3.7 dB

Filter  1: ON PK Fc  1724 Hz Gain +2.99 dB Q 1.32
Filter  2: ON PK Fc    69 Hz Gain -1.76 dB Q 2.96
Filter  3: ON PK Fc 15933 Hz Gain +2.42 dB Q 0.62
Filter  4: ON PK Fc   121 Hz Gain -1.31 dB Q 1.31
Filter  5: ON PK Fc   639 Hz Gain -2.81 dB Q 3.00
Filter  6: ON PK Fc   233 Hz Gain +0.94 dB Q 0.07
Filter  7: ON PK Fc  2938 Hz Gain -1.19 dB Q 2.87
Filter  8: ON PK Fc   861 Hz Gain -1.02 dB Q 2.73
Filter  9: ON PK Fc  9351 Hz Gain -1.51 dB Q 2.95

filters_eq.jpg
 
Last edited:
I don't see it's discontiued actually, not on the M-Audio site, and not in stores in europe. And here it's very cheap: https://www.thomann.de/be/m_audio_b...LCJjdXJyZW5jeSI6MiwibGFuZ3VhZ2UiOjJ9&reload=1

And in other stores it's also on stock, or on backorder with short expected delivery time.

On the speaker itself (a friend owns a pair), i know that one, and for it's price down here (130-150€ for a single one) it's a great speaker. But if they charge 500$ for it like some say it's way to expensive. It's not a bad speaker, just a bit hard and not so detailed sounding subjectivly. But much better than all i know at it's EU pricepoint. The graphs confirm more or less that subjective id I had of them.
 
I‘m looking for something decent to replace a Marshall Bluetooth speaker with and this might be it for 130€.

Other speakers I considered are Adam T7v and Kali LP6v2 but I can’t tell if they’re worth the 80€ premium over these M-Audio speakers
 
I‘m looking for something decent to replace a Marshall Bluetooth speaker with and this might be it for 130€.

Other speakers I considered are Adam T7v and Kali LP6v2 but I can’t tell if they’re worth the 80€ premium over these M-Audio speakers
What source would you connect for these speakers, or Kali?
 
What source would you connect for these speakers, or Kali?
Raspberry Pi with DAC board running moode and Camilla DSP.

This allows for some speaker corrections and also mixing to mono because I only need one speaker
 
I guess it was previous "D2" gen. that had round tweeter waveguides and sites/reviewers sometimes threw random pics and caused confusion (?)..
My local price comparison site shows D2 was sold in years 2011-2017, this D3 2017-till now (so both ~6years), so maybe some D4 iteration slowly on the way, maybe also not due to market expectations..

Anyway this is Class A/B amplified, out of curiosity someone could measure power consumption and compare it (volume matched) with some class D monitors, like LSR308, T8V or so..
 
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