Originally Posted by Molon_Labe
If the M2 isn't a wise choice for HT, does anyone want to speculate why JBL chose them for the Atmos demo at CEDIA? If it was to showcase theater, why did't they go with a Pro Cinema product? Many people did criticize the bass and mid bass of the room and it seems to line up with what everyone is saying about the single 15 of the M2. The room apparently was loud while the M2 isn't designed/intended to be played loud. Seems odd.
I'm not sure if you were there?
I was twice.
The bass was the best at CEDIA IMO.
They used (8) 18" subs, and it was not for output. It was for seat to seat variation management, and using their system the variation seat to seat (a lot of seats too) was +/-1db.
Not sure where you got that info, but that is one of the problems with second hand and subjective opinion. I know this for a fact because I talked to the guys there who measured it and set it up. He even explained why in the demo.
They also used a lot more overheads. A LOT MORE. because that is one of the tricks you can use to avoid the localization problems and minimize SPL variation seat to seat for surrounds and overheads.
I thought that the demo was oustanding. M2 included.
And they choose the M2 because they play plenty loud, but work better (more favorably with room interaction) in that set up (at least they felt that way). I suspect they also wanted to showcase their product they were most proud about, and since M2 was much new than something like a 4722 that was designed back in 1996.
Why would the M2 not be a good choice for theater? It's used in professional mixing FYI. It's top SPL is comfortable well above reference too. One of the advantages of a great speaker like M2 that has a nice wide pattern and excellent directivity is that you are opened up and free to use a variety of different room treatments, which can provide superior sound and add in that illusive "sparkle" in the room. You can't get that with a narrow pattern speaker, and absorb panels. You can of coarse use the same treatment approach with something like an M2, but personally I would not. The main advantage of that speaker is you can bring in and use all that great energy and use alternative room treatments.
At one of the last GTG we did we compared a variety of speaker types (all good stuff) and used some of the HAA tracks that test for envelopment and I think a lot of the attendees were shocked at the results. The test was informal, but it was enlightening. We used a ribbon based tower speaker, a JTR (horn) , a MTM soft dome based DIY I made, some FUSION 8 (horn). I think a lot of people thought the bigger speaker would sound "bigger" but actually it was the opposite. The JTR was the smallest sounding, with the sound clearly focused in front of you, shrunken almost into a smaller oval of origination. It has decent focus, but poor envelopment. It was clearly great sounding, loudest, most dynamic etc... everyone agreed on that part. We had to pad it down quite a bit to even try to level match it to the ribbon or MTM bookshelf. Obviously the higher efficiency was clear. But the ribbon sounded bigger than the FUSION 8 and the JTR, because it had a wider axis horizontal. But it was limited very much in the vertical, and this was obvious to everyone when we stood up and sat back down, you could literally take yourself out of the direct sound. I don't remember the specifics of that ribbon- but I know the technology is generally really limited in the vertical- sometimes only 20 degrees or so. 120x20 would be really wide, but make sure you stay seated! You won't get as much from the floor and ceiling reflections on the top end, and that was also noticable. The soft dome sounded the best. It was also the most enveloping. The speaker would not be well suited to HT because of bass response and output, it was not very efficient. The parts were modest- A $20 dayton soft dome and two 4" woofers. It was sealed. All speakers ran with (3) Seaton subs so bass response was mostly the same, with all speakers XO as well at 80hz. In this set up the small speaker was not particularly disadvantaged like it might be in a 2.0 set up- but the point was to judge the full sound and judge envelopment and sound stage. The soft dome had the biggest sound- you could clearly hear the sound coming from the side, above, even behind you.
The best track we used for this test was Pink Floyd song "TIME" where the clocks all ring like crazy in the begin of the song. With a system with great envelopment you'll get a sense of reflections and sound all around you- with some clocks clearly farther away, closer, to the side, etc... and you'll hear room clues from the recording and your own room that kind of puts you in the middle of the sound. The soft dome with the small woofers had a great off axis, as do most small speaker designs with dome tweets, so it was a pretty obvious difference between the JTR horn (which is much more narrow and pattern controlled) and the soft dome. If you followed the logic of most AVS people you would have thought the opposite- but again this is an area where a lot of people don't know or don't actually have training.
Our friend Bob who attends often actually supplied the test disc and suggested the test (he had taken the HAA audio calibration class, as well as many more similar classes) HAA link #1 info HAA SECOND LINK FOR INFO.
Here is a picture I had on my phone from the event (sorry I did not really take many)
Room was untreated basically. A normal room, with a area rug and hard wood floors, standard construction painted sheet rock, ceiling (with skylights) and some windows with light curtains on one wall. This was not some special room. The host has been working on treating the room to further improve the sound quality, but I point this out because I don't want some people to think it was a special circumstance that would not play out in ordinary rooms.
Circle back to the topic at hand- the M2 really has a lot of the advantages of smaller speaker, or wider speakers, but in a bigger package able to deliver better dynamics. They have something like 10,000 watts powering them too so dynamic ability certainly isn't a problem- each woofer and each tweeter get's it's own channel of power dedicated from a Crown Itech amp. You are able to do more things in your room design or room treatments with a speaker as excellent as the M2 because of how excellent it performs. The sweet spot is wider thanks to that waveguide, which is also something I assume JBL pro considered in their multi seat multi row room. You get a different first reflection point, and you get a favorable room interaction thanks to great off axis performance.
That said, the 4722 is an excellent speaker, and it's 90 wide (pretty good IMO), very dynamic, and the directivity index looks pretty good for it. It's better than most I have seen in this class. It's not the final word in refinement, which is something the M2 would hold a serious advantage about, but it does sound good. It can work in a lot of designs and rooms, (assuming you can fit these beasts !). But it's not an M2. There is a lot more reasons why the M2 is almost 10x the price, but this conversation needs to end some place, might as well stop here.