Axiom Home Page Forums General Discussion Advice from Axiom Owners Pros & Cons using 2 M2is as Centers

Hello all,

Hope you are all well. I have been thinking of using 2 M2i for my center channel, this would place all listeners within +/- 20 degrees off axis.

My room is 18 wide X 12 deep. The seating area is 7.5 feet to the closest person to 9.5 feet to the farthest person from the center channel speakers.

I will run them in parallel as a 4ohm load to my HK 630. I will use them in a vertical position, tilted down toward the listening area from above the television on its left and right corners. The spacing between them will be about 16 inches.

Cominbed output of the two should be slightly better than one M22Ti, and will have greater dispersion throughout the room.

Is anyone using a setup similar to this? If you are, how does it sound?

This will be my first Axiom purchase, I want to see how they sound. I figure that since the M2i has the same woofer and tweeter as the M60Ti that it will represent the Axiom sound very well for a small expenditure of money.

Thank you,

TonyM

One correction, the M2ti uses the same tweeter and midrange driver as the M60. The M3ti uses the same tweeter and woofer as the M60. The drivers in the M2 are the same as in the VP100 & 150. They are also ported speakers which should also affect their output. Mounted on the full metal bracket they should give you much more adjustabilty for fine tuning directionaly that would a single long box center speaker. Seems to me it makes a lot of sense.

Hello md55,

I believe you are thinking of the old M2Ti, the new M2i without the T uses the 5.25" woofer and the same titanium tweeter as the M22Ti and the rest of the Axiom line.

Yes, the ported design of the M2i is one of the big reasons I am thinking of going this route instead of the non-ported designs of the VP series of centers. Plus, like you said, it seems that two seperate centers give far more adjustment options.

Thanks,

TonyM

We are getting somewhat into semantics here. The 5 1/4" "woofer" in the M2 is the same as the midrange driver in the M60s as opposed to the 6 1/2" woofers. While the 5 1/4" drivers are called woofers when they are the largest driver in the speaker I was just trying to clarify they are the same as the midrange in the M60 and that the M3 would have the same tweeter and woofer as the M60. Since deep base response is not what we are looking for in a center channel I don't believe this is really an issue if you were trying to match M60's. Where this might be more of a consideration is if you were using the M40 or M50 for mains since they both lack the 5 1/4" midrange driver.

I have M50's with a VP150 center. I don't find the voicing between the VP150"s 5 1/4" "woofers" and the M50's 6 1/2" woofers to be a problem but others have commented on a slight difference in voicing.

Given what the center channel mainly does, which is produce dialog it makes sence that the 5 1/4" midrange driver as a "woofer" makes the most sense.

I'm not sure about this, but I think the older M2ti have a 3/4" tweeter rather than the 1" tweeter which now runs across the Axiom line with the exception of the QS4. It used the same 5 1/4" midrange/woofer as they do now. It gets confusing because the driver mix has changed towards more uniformity in the last year or so. I believe that the QS4 is the only speaker now that does not use any of the three drivers common to all other Axiom speakers (1", 5 1/4", and 6 1/2").

For multi-channel music with M40's and 50's perhaps the M3's would be a better choice of centers. I rarely listen to music in a surround mode that uses the center channel. I find stereo recordings generally send too much information to the center when played in surround modes. The exceptions to this are music recorded in DTS multi-channel and some recordings made in large resonant halls. Like a recoding I have that combines pipe organ and pan pipes recorded in a large stone church.

Bottom line, I think your approach has a lot of merit.

TonyM, the M60 has dual 6.5" woofers in addition to a 5.25" midrange. The M2 uses the 5.25" driver, not the 6.5".

Also, I remember reading on the AVS board sometime ago that there are some problems with running dual centers (other than the increased load it presents to your receiver). Unfortunately, I don't remember what the specific issues were.

I'm sorry that I don't know more about it... perhaps one of our more knowledgeable board members may comment.

md55, ditto to those comments about surround modes and music - it seems like everythong goes to the center.

And I believe Axiom just added the 1" tweeter to the new QS4s.

When I raised this idea about a year ago, Alan told me that it would be just fine with my H/K 525. So as long as your reciever/amp can handle the 4 ohm load, you should be good to go. I'll be curious how it works out.

I just checked the specs and you are right the QS4 now uses the 1" tweeter. So the only anomally now in the Axiom lineup is the QS4's use of a 4 1/2" midrange/woofer.

I wonder if the tweeter change corresponded to the price increase?

I'm curious what the problems would be with the above configuration. Don't most movie theaters actually spread the center channel out several yards across the front screen with 2 or even three speakers so as to spread out the center information for better imaging throughout the theater?

You would think that if you were sitting dead center, in between them, you would get a great, well grounded, "phantom center" center channel, and if you were off axis, the dialogue woudl still appear to come from the center of the screen despite it being off to one side, if only very slightly.

In a large, wide room, I can see how this application woudl eb very useful. It would probably only be problematic when mixing sounds in between the front channels and the center (like in a pan). The sound may appear to "jump" across the screen too much and sonud unnatural.

Anyway - very interesting thought.

Hello Capn_Pickard,

Interesting thought on the panning. The left center will be about 8'6" from the left main, and the right center will be 5'8" from the right main. There is an opening to the dining room to the left of the seating area, that is why there is a difference in spacing on the left. So there is a lot of distance between the mains and the center speakers, so pans should be distinct from the centers to the mains.

I remeasured the angles from the center of the TV to the left and right outboard recliners that are on either side of the couch, they are about 65 degrees off axis. To include these recliners would be difficult, since that gives a 130 degree coverage area from one side to the other.

Even 2 speakers for the center will not include them in the sweet spot for the center, it is a difficult seating arrangement to accomodate.

Maybe if I utilize my pre-amp outputs from the HK 630 and an external amp, I could drive another set of M2i and angle them out to include the outboard chairs. I will only do this if 2 does not give crisp dialogue to those 2 seating positions.

Decisions, decisions. Isn't audio fun?

Thanks,

TonyM

Hello md55,

You are indeed correct, the M2i utilizes the same size midrange driver and tweeter of the M60Ti. I apologize for any confusion.

Thanks,

TonyM

No problem, The discussion brought to my awareness that the QS4 had changed. I wrote as much as I did in case other browsing at the forum were interseted. Let us know what you decide and how they work for you. It's always good to get feedback on other solutions.

Professional speakers with horns are frequently designed to be arrayed because they have a fairly predictable dispersion pattern. Tweeters such as found on the M2 do not have a horn, and I believe have more problems with lobing when arrayed. Whether these problems would bother you or whether you would believe them to be better than a single VP150 is another question.

Of course, on the other hand, systems such as the VP150 don't have horns, either, so maybe it just doesn't matter with home systems or people just ignore it. I don't know...

Bruce

Tony, welcome. In the past I did a fair amount of experimenting with center channel configurations(although I didn't have the M2s). In short, I think that what you propose would work well, although I doubt that it's really necessary. The problem that Mark(BigWill)read about somewhere may be "comb-filtering" when two separated speakers reproduce the same material and partially interfere with each other. This does exist, but it can also happen occasionally with the regular two stereo speakers and in my view shouldn't be given much weight, especially considering all the comb-filtering that's happening continuously in any listening room that isn't an anechoic chamber. The center image will shift slightly as the listener moves to the left or right, but won't move out farther than the center speaker on that side, which should be satisfactory.

The reason that I said that it shouldn't be really necessary is that a single vertical speaker which has very wide dispersion should be adequate, as I've found. Despite a rather puzzling recent report of an M22 having a narrow "soundstage", both my personal experience and the NRC measurements show that the Axiom tweeter has very wide dispersion(which is what determines the soundstage when other factors are held equal). So, a single vertical M2 should be very satisfactory, although your experiment will be interesting.

JohnK,

I kind of like the idea of two M2Is or M3Ts as centers. We will be moving to Florida within the next few weeks and purchasing a house soon there after. The plan is to establish a HT room. This may be a viable consideration, although it will require some experimentation. I have some time to think about it and am looking forward to future posts on the subject.

Jim / CAV104th

"THE MORE YOU KNOW, THE MORE YOU DON'T KNOW"

Hello All,

Thank you for all the replies. There seems to be quite a bit of interest generated by this concept. I will be purchasing the speakers, most probably, in the next 2 weeks to try it out.

Will keep you all posted.

Thanks,

TonyM

Hello Jim,

Interesting that you bring up horn tweeters, currently I am running an 8" mid/woofer with two large piezo horn tweeters angled outwards for my center channel. This does not work very well, it is too harsh in the high end and the mids are not very distinct. This setup moves a lot of air though. My Wife and I often question each other about what someone said in a movie, and neither of us caught what it was. My H/K 630 I doubt is the problem in this scenario, it deserves better speakers.

A single speaker may be enough, but I am used to a lot more volume than I believe one M2i can generate. Two together I believe should be 3db louder than one alone. Please correct me if I am wrong here.

Thanks,

TonyM