Revel M106 Bookshelf Speaker Review

[KaiserSoze]

I guess monitors are rarely on the flour or near the floor.

Please accept my advance apologies for pointing out that while monitors are not often near the floor, they are almost never on the flour.

 

[Beave]

Since we're correcting use of wrong words, the word you should have used in post #163 is infrasonic, not subsonic.

PS. He did write that monitors are "rarely on the flour...," which is not so different from you writing that they "are almost never on the flour."

 

[KaiserSoze]

I'm reading more and more articles on how folks are favoring crossing over the subs at 150Hz. I'd say, it's become prevalent in the past 5-7 years due to most folks coming to the realization that bookshelves are terrible below 100Hz, and most systems now use multiple subs. So, localization is not a problem.

I love the dispersion of a 5" mid, give it room to breathe by crossing over at 150Hz/12dB down to subs beneath the stands, etc, acting like a 3 way, and the sound improves dramatically. I agree, subs are a requirement in most systems, IMVHO.

Back around twenty years ago I managed to have a telephone discussion with a technical product manager (something of that sort) on the subject of the way bass management is done in home A/V receivers. This was prompted by my having noticed in their specs that some of their receivers had dual LFE outputs. This suggested to me that they might be doing the bass management and subwoofer crossover thing independently for the two stereo channels (after combining the LFE channel independently with the right and the left). I did not get a definitive answer but I think he emailed a block diagram and either from it or from something else I concluded that they simply had provided two outputs for the single LFE channel. Of course the LFE output isn't the same as the .1 in a 5.1 or 7.1 or X.1 multiplex. With most any A/V that's ever been made (especially since they converted over to fully digital processing whenever that was exactly) the .1 channel in the multiplex is combined with the other channels and the LFE channel that is output from the receiver is then generated from the combined signal. This is the only approach that would make any sense, and it clearly demonstrates that have a separate LFE channel in the multiplex was a stupid idea that never really made good sense. And this was what put on the path that leads to where we are today, where it would easily be possible for an A/V receiver to generate two separate LFE outputs, one for each of the two main channels, the benefit of which is that it would permit proper blending of the subwoofer frequencies with the frequencies assigned to the main (bookshelf or stand-mounted) speakers. So far as I know there is still no consumer A/V receiver that does this even though it would be extremely simple and substantially valuable given that nowadays most people's main stereo speakers are small bookshelf speakers that ideally would take over not below 200 Hz. I was frustrated by this twenty years ago. The manufacturers of mainstream home A/V gear are always fully on-board with the very latest multi-channel scheme that comes along. Perhaps if some corporation would patent and promote a bass management scheme where independent LFE channels are extracted for each channel, and demanded a royalty from any manufacturer who does it this way, the manufacturers would all get on board and finally do what they should have realized needed to be done more than thirty years ago.

 

[KaiserSoze]

Every time I've tried crossing higher than 100Hz, I didn't like the way it sounded.

Remember, crossovers are on a slope. If you begin at 150Hz, you will only be 24dB down at 300Hz, and 48dB down at 600Hz. That leaves a large range for your music to come through the subs...on the floor.

Same here. To cross from the sub to the mains at frequency higher than about 100 Hz, even with 24 dB slope, you need a pair of subs each located next to one of the mains and taking signal from the speaker wires. There are very few subs that will allow you to set the crossover frequency as high as 200 Hz, and most of them are not the least bit flat on up to 200 Hz, because they are high Q designs by intent, for better efficiency. And even if it goes well enough with the subs, you still have to jury-rig a high-pass filter to the main speakers and try to get a proper slope.

 

[KaiserSoze]

24db down by 300 is likely great.
I don't think there will be a problem with the floor. It is a very wide wave anyway.
A 150hrz wave is 8feet roughly.
300 is roughly 4. But really wrapping around and bouncing all over anyway.

There are two potential problems. One is the sub revealing its location. The other is with destructive interference ("phase cancellation") between the wavefronts from the main speakers and the wavefront from the sub for listeners that are off to one side far enough for the two distances (the distance to the sub and the distance to either main speaker) to differ by a half-wavelength. At 300 Hz a half-wavelength is 3.75 feet.

 

[KaiserSoze]

Since we're correcting use of wrong words, the word you should have used in post #163 is infrasonic, not subsonic.

PS. He did write that monitors are "rarely on the flour...," which is not so different from you writing that they "are almost never on the flour."

Oops, me used the wrong word. The post was intended for people with a sense of humor. I didn't understand your P.S., except by inferring that you didn't get it, which is weird.

 

[Beave]

A funny reply after he mistakenly used the word flour was fully warranted. I'm sure somebody could have come up with something clever. But all your post did was to repeat his mistake, inentionally of course. I fail to see the humor in that.

 

[KaiserSoze]

Even 2-3" from the wall should be plenty of room to not restrict airflow. Also, with a proper setup crossed to subs, output form the port will be greatly reduced anyways.

I think that the virtual surface area of the virtual cylinder with diameter matching the port diameter and height equal to the distance from the port to the wall should be somewhat greater than the area of the port opening. The two areas will match if the distance to the wall is equal to half the radius of the port. If the distance to the wall is equal to the diameter of the port, the virtual area of the virtual cylinder between the wall and the rear of the speaker will be twice great than the area of the port opening, which is likely more than adequate. The bigger concern I would have is with a reflection off the wall re-entering the port and a standing wave setting up that would modulate the pressure inside the enclosure and potentially modulate the woofer cone.

 

[KaiserSoze]

Definitely a good point. However, if using cost as a strong consideration, I suppose one would also have to consider Revel F36 for approximately the same cost as the smaller, less capable bookshelf. With stands, the towers are probably cheaper.

I also concede that the M106 turned in very impressive performance. Distortion profile is very impressive, so obviously using much higher quality drivers than the Concerta 2 line.

Cost should always be a foremost consideration. Regardless of how much you are willing to spend, you want to get the best speakers you can get for that amount of money. How would it make sense to buy something that wasn't the best you could get for the amount of money you spent? Personally I would prefer a pair of F36, or even a pair of F35 for that matter, and would be happy knowing that there aren't going to be any issues with a single sub crossed over at 80 Hz. (Unless of course you decide to go with multiple subs to even out the room modes a bit, in which case the need for the main speakers to be fully capable of being crossed below 100 Hz is even more important.)

 

[KaiserSoze]

A funny reply after he mistakenly used the word flour was fully warranted. I'm sure somebody could have come up with something clever. But all your post did was to repeat his mistake, inentionally of course. I fail to see the humor in that.

Thus demonstrating that you are not among the audience for which it was intended.

 

[beefkabob]

I think 96db is too low for the distortion test, and we need any speaker that can handle it to do 105 or so. That just so happens to be the max where I'll listen to a whole song.

 

[YSDR]

I think 96db is too low for the distortion test, and we need any speaker that can handle it to do 105 or so. That just so happens to be the max where I'll listen to a whole song.

105dB from what distance? If you sit 2m from the speakers then you need 111dB at 1m to get the 105dB at 2m, at 4m you need 117dB at 1m and so on. Double the distance and the SPL drops by 6dB.

 

[Chromatischism]

Even 2-3" from the wall should be plenty of room to not restrict airflow. Also, with a proper setup crossed to subs, output form the port will be greatly reduced anyways.

Very true about the subs. The ports will still be active, just less so.

Without subs though, I could see the increase in pressure they will experience to have some kind of effect, I just don't know how big of a deal it is. Anyway, I think 6" is plenty close enough. That pushes the wall bounce cancellation up to 565 Hz if I'm doing the math correctly, which is out of the modal range and therefore effectively eliminated.

 

[Chromatischism]

Also similar to the Buchardt M400.
https://www.audiosciencereview.com/forum/index.php?threads/buchardt-s400-speaker-review.12844/
Same mid-woofer, the SB Acoustics SB17NBAC35-4: https://sbacoustics.com/product/6in-sb17nbac35-4/
Only in the Buchardt it is messed up by poor cabinet construction and resonance.

There's no cabinet resonance. The 500 Hz anomaly is likely the passive radiator interacting with the active driver and is not audible.

 

[Chromatischism]

What about with stereo subs/mid basses that are separate from the mains but placed in stereo nearby? (but more optimally placed than the mains would be for speaker boundary interference cancellations/nulls in the 80-150hrz zone?)

If you could get them close enough to the wall, they could essentially serve as speaker stands for your standmount speakers. That is the best way I could think of doing an MBM. Or you could just buy towers.

 

[Koeitje]

Definitely a good point. However, if using cost as a strong consideration, I suppose one would also have to consider Revel F36 for approximately the same cost as the smaller, less capable bookshelf. With stands, the towers are probably cheaper.

I also concede that the M106 turned in very impressive performance. Distortion profile is very impressive, so obviously using much higher quality drivers than the Concerta 2 line.

If I could have found a deal on the F36 that would have been an option, but compared to what I paid for the M106's, a pair of F36's would have been about €1000-1200 more still.

 

[Senior NEET Engineer]

Also, I’d like to point out that these are 7-8 years old.

That distortion isn’t really audible, the average person needs the THD to be around 20% at 100Hz. That’s with content playing, with test tones it would be lower, here is threshold for individual harmonics .

What is the basis for "20% THD at 100hz inaudible"

 

[MZKM]

Say what? I studied this table for just about 30 seconds and noticed that there are only two numbers on it as big as 20%, both of which apply at a subsonic frequency more than three octaves lower than 100 Hz. According to this data, typical threshold of audibility values for 3rd and 5th harmonics at 100 Hz and at high volume are in the ballpark of 1% to 2%. For the 80 dB level at 100 Hz the threshold of audibility is .7% for F3 and a low, low .22% for F5. I don't see any possible way to come up with 20% from this table for 100 Hz. Wait, I finally see it. Yeah, that's it. You multiply the individual percentage values for 100 Hz all together, for all three levels! Oh darn it, that comes out to about 2%. Okay. What you do is, you multiply the four percent values for the 110-dB level and the four percent values for the 100-dB level all together, and leave out the lower numbers for the 80-dB level. Yep, that's it! Hey, I figured it out. 22%.

Those are test tone audibility thresholds; the 20% was for audibility with “content” playing.

 

[Bear123]

If I could have found a deal on the F36 that would have been an option, but compared to what I paid for the M106's, a pair of F36's would have been about €1000-1200 more still.

Europe then? I was offered F206 for $2100 shipped but went with the F36 due to substantially higher sensitivity, and I actually prefer the way they look. Visible screws/mounting hardware just seems like a cheap speaker to me aesthetically. Seems as though we are able to get them much much cheaper..well below MSRP where it seems you must be paying above MSRP.

Do you have subs?

 

[Koeitje]

Europe then? I was offered F206 for $2100 shipped but went with the F36 due to substantially higher sensitivity, and I actually prefer the way they look. Visible screws/mounting hardware just seems like a cheap speaker to me aesthetically. Seems as though we are able to get them much much cheaper..well below MSRP where it seems you must be paying above MSRP.

Do you have subs?

I got a deal on M106's, 1200 euro for a pair (imported from the UK). But that was after 2 months of looking for sales, they never go on sale in Europe. F36's are 1200 euro's a piece. F206 2000 euro's a piece. I asked for discounts on the M106 at a Dutch dealer, and the most they could give was 10% on MSRP. So its basically more a case of finding good deals on them, but its virtually impossible in Europe to get them.

I got a single SB2000 right now, looking for a second.