• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

Revel M55XC Outdoor Speaker Review

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
28,184
Likes
72,676
Location
Seattle Area
#1
This is a review and detailed measurements of the Revel M55XC "extreme outdoor" speaker. It was kindly purchased new and sent to me by a member. I believe he is using it for surround on-wall application (indoor) due to small dimensions of this speaker. The retail cost for M55XC is $600 but there is a special (end of life?) going on bring the price for a pair down to US $420.

Note: our company, Madrona Digital, is a dealer for Harman and hence Revel speakers. I don't know for a fact but we install a lot of outdoor Harman speakers in commercial and residential installations. So feel free to read as much bias as you like into this review.

This is a very compact speaker as outdoor ones usually are:

Revel M55XC Wall-mount outdoor speaker Review.jpg


There is sturdy metal grill that protects the drivers (which I did NOT use for measurements). The back panel shows screw terminals which is more of a standard for outdoor speakers (a boot covers and waterproofs it):

Revel M55XC Wall-mount outdoor speaker back panel terminals Review.jpg


There is a plastic plug that you pull out where that dial is on the bottom to adjust the impedance for higher voltage drive to accommodate long speaker wire runs. I tested it in the default mode which is for normal amplifier wiring.

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 used over 800 measurement point which was sufficient to compute the sound field of the speaker. Measurement axis is the tweeter center.

Temperature was 78 degrees. Measurement location is at sea level so you compute the pressure.

Since this is an on-wall speaker, it is likely designed to get bass enhancement from the wall behind it. I could try to build some kind of wall to measure it that way but seemed too much work :). So what you see is the free-air measurement without such which will likely show lack of bass output.

Spinorama Audio 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:

Revel M55XC Wall-mount outdoor speaker CEA-2034 Spinorama  Frequency Response measurement.png


As we could have guessed, bass output is too low relative to tweeter when measured assuming no walls behind it. Hard to then draw the trend line. I took a shot at it which would naturally show the speaker to be "bright" lacking bass without wall enforcement of bass.

Note how smooth the directivity is (dashed blue) line. And freedom from resonances. I have private measurements of a number of "architectural" speakers and they are generally horror shows.

Early reflections then show similar response to on-axis:

Revel M55XC Wall-mount outdoor speaker CEA-2034 Spinorama Early Window Frequency Response meas...png


The rising directivity naturally reduces some of the highs making the response more flat.

Putting the two together we get a predicted in-room response which says what we already know:

Revel M55XC Wall-mount outdoor speaker CEA-2034 Spinorama Predicted In-Room Response Frequency...png


Here is the impedance graph:

Revel M55XC Wall-mount outdoor speaker Impedance and Phase measurement.png


Here is the response of the individual drivers:
Revel M55XC Wall-mount outdoor speaker Woofer Tweeter response measurement.png


Speaker Dispersion Measurements
Looking how wide of a beam the speaker projects without much loss of energy we get:

Revel M55XC Wall-mount outdoor speaker Beamwidth Response measurement.png


We get a good 110 degrees with very smooth response.

Same in 3-D:

Revel M55XC Wall-mount outdoor speaker Horizontal Directivity Response measurement.png


There are a lot of hi-fi speakers that fail to produce such an even response.

And here is the vertical:

Revel M55XC Wall-mount outdoor speaker Vertical Directivity Response measurement.png


Since you are wall mounting this speaker, this is an important measurement. Point the speaker down and keep it withing -30 degree window.

Speaker Distortion Measurements
Let's look at our Klippel system measurements first:

Revel M55XC Wall-mount outdoor speaker Klippel Relative Distortion THD measurement.png


Looking at the left graph, we see that the not asking the little woofer to produce too much bass results in much lower distortion numbers. Once you turn it up though, distortion climbs in the rest of the range (right).

I should have captured the response at 86 dB but for consistency here is the distortion level at 96 dB:

Revel M55XC Wall-mount outdoor speaker Klippel Distortion THD measurement.png


Switching to Audio Precision analyzer we start with loudness compression:

Revel M55XC Wall-mount outdoor speaker Linearity Compression measurement.png


This is very nice. There is essentially no loudness compression even at 114 dBSPL @1 meter! This speaker should play loud.

Taking a deep dive into distortion relative to frequency, let's look at 86 dB SPL:

Revel M55XC Wall-mount outdoor speaker THD 86 dB distortion measurement.png


And at multiple levels:
Revel M55XC Wall-mount outdoor speaker THD  distortion measurement.png


Displacement which mostly happens in bass frequencies is our enemy when it comes to distortion and we see this once again in above chart.

Finally here is our 32-tone test resembling "music:"
Revel M55XC Wall-mount outdoor speaker multitone distortion 86 dB SPL measurement.png


We actually beat our reference in above test. Here is the comparison at two levels:

Revel M55XC Wall-mount outdoor speaker multitone distortion 102 dB SPL measurement.png


Speaker Subjective Listening Tests
I started testing with the M55XC in my usual location which is at least 4 feet from back wall and 3 foot from side wall. Lack of bass was quite obvious so I moved the speaker back so that it has my system and Reel-to-Reel and TV behind it. That nicely boosted the bass although the speaker was still a tad bright. Proper placement on the wall would likely take that last bit away.

I then went through my usual playlist and was shocked how closely the sound of this little "outdoor" speaker resembled my much larger home Revel speakers. Clarity was superb. Distortion was nowhere to be found even when I turned the volume up. Indeed this speaker could handle incredible amount of power pumped into it without strain. Not letting it produce too much bass helped a lot here.

Tracks like this from Greek artist, Eleni Karaindrou's Medea album were to die for:
Eleni Karaindrou.jpg


Sadly I can't find an online stream to share with you.

Another great performance (among many) was Patty' Griffin's Living With Ghosts Track, Cold As It Gets:

Patty Griffin.jpg



Track after track impressed.

Conclusions
I don't know what to tell you all. I keep wishing there is a Revel speaker that doesn't perform so I can put it down and in the process look unbiased. But I can't. These things are designed so well, even in this utilitarian outdoor packaging. Clearly similar design process is used for them as their home hi-fi gear (something Kevin Voecks of Harman confirmed with me years ago).

Using these of unobtrusive surround application indoor would be quite good as well as outdoor. And there, the much higher cost can be justified easier. Alternatively if you can place them against the wall, they will make very good "bookshelf" speakers.

Alas, if they are being discontinued, then we are late to the party. So better rush to get them. I might do the same myself....

Needless to say, I am very happy to recommend the Revel M55XC.

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

Audio products that perform well always cheer me up so I don't need your money for that. But if you insist, you can donate using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 

Attachments

OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
28,184
Likes
72,676
Location
Seattle Area
Thread Starter #5
Looking at the graphs, I assume you did not use full toe-in? That bright on-axis which also causes a flat in-room severely lower the preference ratings.
I did not.
 

restorer-john

Major Contributor
Joined
Mar 1, 2018
Messages
4,712
Likes
10,144
Location
Gold Coast, Queensland, Australia
#7
For a small, outdoor, weather protected speaker, the performance looks to be excellent. I don't think I've ever heard an outdoor speaker that would be equally at home indoors- they are usually horrible sounding.
 

franspambot

Senior Member
Forum Donor
Joined
Mar 30, 2019
Messages
463
Likes
853
#8
Don't forget that the bass will improve once mounted properly. If that wide dip fills in... In many ways, the measurements don't do full justice to the speakers as they are not really meant to be heard in free air. This is one of those reviews where the subjective portion matters more than usual. I'll have to take Amir's word for it. That said, if you are referring to the distortion, then yes that doesn't seem like a home run. Certainly they are not meant to be PA speakers so they should also not be judged as such. It would be interesting to know just how much distortion is acceptable. The recent, terrific Philharmonic BMR review by hardisj brings up this question very well. People criticized the M16s for their distortion too, if I remember correctly (with respect to its panther award).
 

carlosmante

Active Member
Joined
Apr 15, 2018
Messages
160
Likes
114
#9
Don't forget that the bass will improve once mounted properly. If that wide dip fills in... In many ways, the measurements don't do full justice to the speakers as they are not really meant to be heard in free air. This is one of those reviews where the subjective portion matters more than usual. I'll have to take Amir's word for it. That said, if you are referring to the distortion, then yes that doesn't seem like a home run. Certainly they are not meant to be PA speakers so they should also not be judged as such. It would be interesting to know just how much distortion is acceptable. The recent, terrific Philharmonic BMR review by hardisj brings up this question very well. People criticized the M16s for their distortion too, if I remember correctly (with respect to its panther award).
"Don't forget that the bass will improve once mounted properly". Don't worry, at the poolside party and some Tequila later nobody cares.
 

DonH56

Major Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
4,460
Likes
6,961
Location
Monument, CO
#10
Very timely, since I am looking at getting four M80XC speakers and suspending them from the ceiling for Atmos. Nice to know their performance holds up so well. Not sure how @amirm finds time for all this but glad he does!
 

tktran303

Active Member
Joined
Mar 27, 2019
Messages
140
Likes
194
#15
Looking at the polar responses, the usual Harman wide horizontal beamwidth philosophy applies here.

And examining the on-axis frequency response, the design has reduced baffle step compensation (See @ 250-500Hz level @ 82.5dB compared to 2-8KHz @87dB)

-> This speaker is designed/voiced for close to wall mounting.

So this speaker is not designed to be placed 2-3 Feet far away from your front wall, like you might do with your usual, large bookshelf or floorstanding speakers (with (near) full baffle step compensation)

The 2-3dB boost at ~150Hz gives a mid bass boost- and makes small speakers sound bigger/capable.
As I inferred, the sound fell flat, when the speakers were placed at the usual position, and Amir moved them almost immediately. I’m not surprised that, then, it sounds reasonably good; given the correct placement (closer to a wall)

I wonder, whether this is the cause for the discrepancy between the Harman Preference score, and Amir’s subjective impressions?
 
Last edited:

echopraxia

Addicted to Fun and Learning
Forum Donor
Joined
Oct 25, 2019
Messages
773
Likes
1,108
Location
Seattle Area
#16
Track after track impressed.

Conclusions
I don't know what to tell you all. I keep wishing there is a Revel speaker that doesn't perform so I can put it down and in the process look unbiased. But I can't. These things are designed so well,
Needless to say, I am very happy to recommend the Revel M55XC.
Preference Rating
SCORE: 2.2
SCORE w/ sub: 5.6
So another example of a speaker that scores very high subjectively (golfing panther), but ranks very low on the Olive preference score.

However it seems unlike some prior cases like this, distortion can’t explain the preference for this one, since distortion is rather high.

Any theories on what could explain this @amirm?

Or perhaps was the recommendation for this model given relative to other outdoor speakers (which as others have said are generally pretty terrible sounding)?

I wouldn’t mind having some decent outdoor speakers and it seems these are certainly among the most promising in that category. They certainly have the best spinorama out of all outdoor speakers I know of - #1 out of a grand total contestant set of 1!

P.S. Looking more at the spin, it really doesn’t look as bad as the score suggests. In fact, if you EQ’ed it to a target curve, I bet the preference score would skyrocket up their with the best of them.
 
Last edited:

jhaider

Addicted to Fun and Learning
Joined
Jun 5, 2016
Messages
984
Likes
1,066
#17
Damn, that looks horrible. Surprised it got a golfing panther. Way too bright, and lots of distortion.
Think about them high on the front and rear walls, as heights for immersive effects. After seeing these measurements, I am...

I don’t like barrier strips for hard to reach speakers, however. The outdoor speakers we use right now (Tannoy and JBL CBT) have Phoenix terminals, which are a cleaner solution.
 
Last edited:

BYRTT

Addicted to Fun and Learning
Forum Donor
Joined
Nov 2, 2018
Messages
684
Likes
1,637
Location
Denmark (Jutland)
#18
...Temperature was 78 degrees...
Good numbers for tomato plants and performance in bass region, thanks review :)..

...Since this is an on-wall speaker, it is likely designed to get bass enhancement from the wall behind it. I could try to build some kind of wall to measure it that way but seemed too much work :). So what you see is the free-air measurement without such which will likely show lack of bass output...
M55XC animated model of estimated gain 1x boundery at 1 feet distance..

Estimated_1x_boundery_1x1x_800mS.gif
 
Last edited:

DonH56

Major Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
4,460
Likes
6,961
Location
Monument, CO
#19
Go look at measurements for typical outdoor speakers, if you can find any. They are terrible. So the rating relative to the competition is valid, IMO.

I am planning to use their big brother as height speakers and they should do quite nicely in that application as well as on the back deck.
 

Dj7675

Addicted to Fun and Learning
Forum Donor
Joined
Jan 12, 2019
Messages
731
Likes
938
#20
These were mine. As Amir said, using them in a home theater install 7.2.6 setup. 3 M106 for LCR, 2 S16 for side surrounds, 2 M16 for surround back and 6 of these M55XCs for atmos. I wanted a decent measuring atmos bookshelf that I could point towards the main listening position and one that included an integrated mounting system. The mount is excellent and I have one pair above my screen one pair on the ceiling behind the main listening position and will have this paint mounted above me on the ceiling. These actually test how I hoped for my use. Reasonable frequency response for their size when mounted against a wall (a few inches), and very good directivity making them very eq friendly. There are compromises of course which is expected with a small sealed bookshelf, but it does the job nicely. I was considering the M80XC but they were just too large for my room. I have taken a couple of in room measurements, I’ll see if I can dig them up as they do measure better where they are mounted or up against a wall.
 

Similar threads

Top Bottom