Revel Concerta C10 Review (center speaker)

[More Dynamics Please]

Having done some information experiments, I believe in the double blind tests that found crossing over up to 150 hz a fine place to crossover when done well (intelligent sub positions, EQ, etc).

This is an important point that's rarely expressed. Many get locked into the dogma that subwoofers must always be crossed over no higher than 80 Hz (or 90 Hz or 100 Hz) to avoid localization and never even try anything higher. In fact with the proper setup it's possible to get satisfying results at higher crossover points before some subwoofers exceed their optimum high frequency range. Believing in the science shouldn't keep us from experimenting.

 

[nathan]

This is an important point that's rarely expressed. Many get locked into the dogma that subwoofers must always be crossed over no higher than 80 Hz (or 90 Hz or 100 Hz) to avoid localization and never even try anything higher. In fact with the proper setup it's possible to get satisfying results at higher crossover points before some subwoofers exceed their optimum high frequency range. Believing in the science shouldn't keep us from experimenting.

True and of course when using multiple subs what you end up with is a MONO signal that appears to be everywhere so if that mono signal goes up to a higher point, it is still not directional in the sense of coming from the wrong place or helping you location the subwoofer.

The "dirty" little science secret is that even when crossing over at 80 hz, there is still audible output from the sub at 160hz -- and even 320hz if you turn off your mains and listen (it's down 24db at that point) -- because it is not a brick wall filter, it is a slope.

And while the common notion that 80 hz and below is "impossible to locate" is generally true, the testing shows that it is actually really hard to locate the source of tones up to 200 or even 300 hz in most rooms because you are not hearing the direct sound. That is below the transition frequency and you are hearing only reflected sound. (We think we can tell where tones at 200 hz are coming from because of overtones at 400hz and 800hz which ARE possible for us to detect since they are above the room transition frequency....and then we attribute the direction of the 200 hz tone to where we hear the 400 and 800 hz overtones coming from... but we aren't actually hearing the 200 hz tone come from a "direction" since there is no way direct sound can happen in a house sized room at that frequency since the waves are too long.)

Anyway, none of this is to say that this Revel center channel speaker is what one would choose if one has more space and more money. Clearly one would choose one of their 2.5 or 3 way center designs -- and that's really only if one wasn't able to simply use the same speaker as the left and right speaker, which is the ideal/industry standard for mastering and theatrical presentation.

But in a budget challenged and/or space challenged situation, Revel seems to have built the best performing speaker of this size and orientation, and at a reasonable price point (especially when on sale or closeout).

Of course, I'd love to be wrong and hear about other horizontal speakers that have the same short form factor, that perform better, even if at a higher price point? Are there any? (For me, wider dispersion would be the first thing I would look for but haven't found in something this short. Sure, a bit more extension would be nice, too, but that's second priority for me, given how rooms sound below the transition frequency and the fact that I do bass management with multiple aligned subs. If one doesn't do that then yes lower extension may matter. And I would list "output" SPL as a factor except this thing actually does remarkably well in that department given its size.)

 

[Dj7675]

Received the speaker back from Amir and listened to it last night against a wall. It must be quite a developed skill to listen to a speaker with limited frequency response. At first listen, I was like hmmm, not sure about this... measured it and it appears to meet sped of -3dB at 110hz. In the manual, they even recommend setting the crossover at 110hz.
Plays very loud without issues which is surprising for how tiny it is. When I added 2 subs to the mix (dual 15inch ported in opposing corners), it did sound very good with crossover set to 120hz. It is just quite evident how important bass is when listening to the C10 without and then with subs.
With the content I listened to, I didn't have an issue with the 120hz crossover localizing the bass. Probably obvious, but with the missing bass, it wouldn't make sense to me to use them in any way without a sub IMO. The assumption is baked in the design tradeoffs and noted in the manual.
I did move around and as you would expect, the 20 degree directivity is quite evident as you get outside of that range. Totally unsientific, but seemed to be about 7-8 feet wide at around 12 feet. This could certainly be an issue if you were seated at a much closer distance as it would shrink.. I should add that I have a Revel c208 below the screen, and at 12 feet, I can't really detect any change in tonality on it with the entire width of the room which is about 14 feet.
Also worth noting, fit and finish is really good. Mounting hardware is well thought out as well. All in all it seems well designed for its intended use.

 

[arisholm]

Received the speaker back from Amir and listened to it last night against a wall. It must be quite a developed skill to listen to a speaker with limited frequency response. At first listen, I was like hmmm, not sure about this... measured it and it appears to meet sped of -3dB at 110hz. In the manual, they even recommend setting the crossover at 110hz.
Plays very loud without issues which is surprising for how tiny it is. When I added 2 subs to the mix (dual 15inch ported in opposing corners), it did sound very good with crossover set to 120hz. It is just quite evident how important bass is when listening to the C10 without and then with subs.
With the content I listened to, I didn't have an issue with the 120hz crossover localizing the bass. Probably obvious, but with the missing bass, it wouldn't make sense to me to use them in any way without a sub IMO. The assumption is baked in the design tradeoffs and noted in the manual.
I did move around and as you would expect, the 20 degree directivity is quite evident as you get outside of that range. Totally unsientific, but seemed to be about 7-8 feet wide at around 12 feet. This could certainly be an issue if you were seated at a much closer distance as it would shrink.. I should add that I have a Revel c208 below the screen, and at 12 feet, I can't really detect any change in tonality on it with the entire width of the room which is about 14 feet.
Also worth noting, fit and finish is really good. Mounting hardware is well thought out as well. All in all it seems well designed for its intended use.View attachment 173132

Thanks for the graph. But even when accepting that it lacks important bass response which can to some extent be fixed with subs: How did that quite substantial dip in the 200Hz-400Hz area with dips down -10dB affect what you heard? To me, this translates to a lack of low/mid-range impact (even with only a minimal room curve) where a center needs to really shine to justify its existence ;-)

 

[nathan]

Those look like room modes. I'm guessing this is in a living room so the transition frequency is close to 400 hz.

 

[arisholm]

Those look like room modes. I'm guessing this is in a living room so the transition frequency is close to 400 hz.

Really? With the center placed on the front wall? Never seen that although it is common with speakers placed away from the front wall ;-) But on the other hand it is to be expected with Amir's measurements showing that it starts to roll off at about 400Hz. And then it gets a peak at 120Hz or so due to the placement. Could be wrong about that of course since I know nothing about the room But nevertheless, that this sounds "very good" is a bit of a stretch based on frequency response alone. It will sound "thin". Simple as that.

 

[nathan]

Two separate things, I guess.

The up/down nature of the graph is what a lot of in room measurements show for even flat speakers due to the room. Room modes exist regardless of speaker placement. I'm not talking SBIR, but just the room modes.

On the other hand the generally lower volume is usually fixed by EQ-ing down the area that is high (ie, roughly -5 db applied to 500 to 20k hz though more precision to hit the peaks might be preferable). That may or may not be worth the tradeoff depending on one's needs. Certainly I'd rather have a larger speaker that didn't do that, if I could fit one. That is, in part, why I use a bookshelf speaker instead of a small center like this. But I am fortunate to have the space and budget for that, and know that not everyone has that option (hence a speaker like this exists to make the most of a sub-optimal situation).

 

[arisholm]

Two separate things, I guess.

The up/down nature of the graph is what a lot of in room measurements show for even flat speakers due to the room. Room modes exist regardless of speaker placement. I'm not talking SBIR, but just the room modes.

On the other hand the generally lower volume is usually fixed by EQ-ing down the area that is high (ie, roughly -5 db applied to 500 to 20k hz though more precision to hit the peaks might be preferable). That may or may not be worth the tradeoff depending on one's needs. Certainly I'd rather have a larger speaker that didn't do that, if I could fit one. That is, in part, why I use a bookshelf speaker instead of a small center like this. But I am fortunate to have the space and budget for that, and know that not everyone has that option (hence a speaker like this exists to make the most of a sub-optimal situation).

True. And many issues like this can of course be fixed with DSP... but still ;-)

 

[Dj7675]

Thanks for the graph. But even when accepting that it lacks important bass response which can to some extent be fixed with subs: How did that quite substantial dip in the 200Hz-400Hz area with dips down -10dB affect what you heard? To me, this translates to a lack of low/mid-range impact (even with only a minimal room curve) where a center needs to really shine to justify its existence ;-)
View attachment 173948

That was just a quick measurement against a wall around 3 feet. That dip is room related. It is now in place above a 122"W screen. Placement is above the screen used as a center height. Green trace is the c10. As you can see that dip is not there at this location measured at the listening position. Also at this location, because it is basically at the top of the front wall near the ceiling it doesn't measure flat like it normally would placed in a normal location. I'm crossing it over around 110hz as per the spec which seems to match the measurements. Works well in this location.

 

[krabapple]

For sure, this thing is for casual TV-use, and only if you don't already have reasonably good front speakers. And dividing a center at 200Hz or higher to avoid their low-end "issues"?? Yeah sure, that will really bring out those powerful centerstage voices and effects For tiny systems which will sound bad no matter what, it is an okay solution... But I personally prefer close to full range centers that are just as powerful and equal quality to the mains. Or else, just use a "phantom center" instead of this puny thing Can't imagine why this is recommended for anything actually, except as I said, for casual TV-use.

A soundbar is far more popular and common for casual TV-use than anything like the C10, which expects fuller range L and R speakers, or L&R plus subwoofer, and near-wall mounting, to perform as advertised.

 

[krabapple]

A subwoofer works at most 100Hz. What human voice is there at that frequency?

IIRC , Dolby mix spec for the LFE channel has it going up to 125 Hz; the Grammy committee recording recommendation is to lowpass LFE between 80 - 120 hz. There are certainly crossover settings on AVRs and subs I've owned that allow that high and higher, if desired, (at the risk of localizing the sub, of course.)

 

[Dj7675]

A soundbar is far more popular and common for casual TV-use than anything like the C10, which expects fuller range L and R speakers, or L&R plus subwoofer, to perform as advertised.

The C10 actually is designed to be used with matching M10 for L/R which would be oriented vertically on a wall (Not that you couldln’t use it with other L/R speakers. Designed for something like this (flat panel on a wall) and a sub...

 

[sarumbear]

IIRC , Dolby mix spec for the LFE channel has it going up to 125 Hz; the Grammy committee recording recommendation is to lowpass LFE between 80 - 120 hz. There are certainly crossover settings on AVRs and subs I've owned that allow that high and higher, if desired, (at the risk of localizing the sub, of course.)

We are talking about bass management, not LFE, and there was a question, which you have not answered.

 

[DonH56]

Male voice fundamental = 85 to 155 Hz; female = 165 to 255 Hz per Wikipedia https://en.wikipedia.org/wiki/Voice_frequency -- other sources corroborate these numbers. We are more sensitive to higher frequencies, of course.

 

[sarumbear]

Male voice fundamental = 85 to 155 Hz; female = 165 to 255 Hz per Wikipedia https://en.wikipedia.org/wiki/Voice_frequency -- other sources corroborate these numbers. We are more sensitive to higher frequencies, of course.

I said at most 100Hz, and you are arguing because of a 15Hz difference, which may possibly be produced by a basso profondo. That looks like an argument for the sake of argument.

 

[DonH56]

I said at most 100Hz, and you are arguing because of a 15Hz difference, which may possibly be produced by a basso profondo. That looks like an argument for the sake of argument.

I'm not arguing anything, I stated the fundamental frequencies of the human voice. This was in response to the quote from you above: "A subwoofer works at most 100Hz. What human voice is there at that frequency?" Simple answer, human male.

Also note that subwoofer crossovers are not perfect brick-wall filters so a subwoofer set to cross at 80 Hz is typically still playing (albeit half as loudly) at 160 Hz.

I have not been following this discussion and see no point. Back to work - Don

 

[Dj7675]

I'm not arguing anything, I stated the fundamental frequencies of the human voice. This was in response to the quote from you above: "A subwoofer works at most 100Hz. What human voice is there at that frequency?" Simple answer, human male.

Also note that subwoofer crossovers are not perfect brick-wall filters so a subwoofer set to cross at 80 Hz is typically still playing (albeit half as loudly) at 160 Hz.

I have not been following this discussion and see no point. Back to work - Don

Appreciate the info and reminder and the note about crossovers. One of the challenges of small speakers like this is for sure the higher crossover and the issues it can bring. One thing I can find bothersome if any voice content gets redirected to the subs. In particular if you are using some kind of harman curve with elevated bass. A few times male voices have sounded boomy or not right, so I played some content with the LCR off but subs on and sure enough there was voice content coming from the subs.

 

[krabapple]

We are talking about bass management, not LFE, and there was a question, which you have not answered.

I wasn't addressing your human voice question.

I'm not disagreeing with you, btw. I think the C10 is good for what its intended use case is. I'm just noting that most modern systems allow the user to output >100Hz content from a .1 channel -- including both LFE (which is Dolby spec'd up to 120 Hz) and bass managed content. For instance, my Denon X3300 allows these crossover settings for bass management: 40 Hz / 60 Hz / 80 Hz / 90 Hz / 100 Hz / 110 Hz / 120 Hz / 150 Hz /200 Hz / 250 Hz.

 

[krabapple]

If sub localizationis an annoying issue -- pulling dialogue off center-- subwoofer placement to the center , under (or behind?) the TV , could conceivably help ameliorate it.

(These are not 'audiophile' solutions, these are real-world compromises.)

 

[krabapple]

FWIW, regarding the system the C10 is intended for -- the C10 plus its vertical wall- or stand- mounted M10 mates + the B120 sub (+M8 surrounds) . The C10 is really just an M10 laid horizontally. Both have a FR that Revel specs at the low end as -3dB @110Hz.

Here is a positive , mostly subjective (but incorporating RTA of the room, that the reviewer used to EQ the sub) of the system.