Axiom Home Page Forums General Discussion Home Theater installing M60's UP-SIDE-DOWN ? in-cabinet style

Hi everyone,

I'm very excited about a pending puchase of some in-cabinet M60's. Interestingly, I plan to install these flush with a living room wall. My in-cabinets will poke out into an unused storage room behind the TV.

My question is this: My wife would prefer it if these rather large speakers were aligned with the top of the TV from an astetic stand point. This would put the M60 tweeter about 5 to 6 feet above the floor; quite a few feet above my ears when slouching in my chair.

However, if I installed the speaker up side down, the tweeter would be more in line with my ears - but now actually be below the TV screen (46" diagonal). Good idea? or not?

Other question: I'm thinking of making an MDF "frame" that will be sandwiched between the drywall and the flange face plate of this in-cabinet speaker. Using a jig, I'd run my frame through a thickness sander and be able to accurately taper it to replicate some toe-in. This would also have a side-benefit(?) of spacing the front surface of the speak out slightly more form the wall surface - hopefully improving standing wave stuff.

I look forward to all ideas!

Sounds fun and I would try the upside down position as a temporary position to see if you like it this way or if it sounds better with the more standard tweeter on top position. If you are adding an extra baffle you could also allow for some slight downward angle towards your listening poisition. Maybe try to have the tweeters aligned with the midline of the screen.

Thanks Jay - I hadn't thought to add a second "frame" to angle it downwards - that could certainly work out very nicey.

Do you think that any of the adgle adjustments will be adding any unwanted / uneven standwave type problems?

Sounds like an interesting install. I agree with Jay that its a good idea to test out the positioning before making it permanent. I think you are on the right track though.

We need pictures, of course...

I'd check with Axiom on the supplementary baffle-thing. I suspect you're over-engineering it. Axiom speakers have very good off-axis response, so it might not be necessary. Also, I can't help but think that those kinds of baffles (besides being a b!tch to build!) would detract somewhat from the aesthetic you are seeking. I don't think it's a "standing wave" issue; I think it is a diffraction issue.

So, your TV is pretty high up, eh?

Where would the tweeters be relative to your ears if you mount the speakers upside-down? I don't see why this would pose any problem. As a matter-of-fact, I think that is a pretty ingenious solution to your wife's concerns.

I suspect Axiom would have taken care to not allow for any standing wave issues inside the cabinet.

Hi axiomoholic,

I don't recall if you sent me the private email with the same question, but I essentially said that it's not a great idea for several reasons. The in-cabinet M60s are not measured or designed to be used in that configuration, nor are the double-blind listening tests done with the speakers inverted so it's anyone's guess as to just how the tonal balance and soundstage will be affected if the speakers are inverted.

Also, the dispersion of the drivers and the tweeter in the M60 is sufficiently good that the tonal balance and soundstage should remain reasonably consistent even if the tweeters are 5 feet above your ear level when you're seated. Keep in mind that about 50% of the sound arriving at your ears is made up of early and later reflections from the room, with the other 50% representing the direct sound from the speakers. This combination helps keep the tonal balance and soundstage consistent over a reasonably broad angle.

The amount the baffle protrudes is carefully adjusted in the design and the crossover to accommodate a fixed distance from the adjacent wall boundary.

Regards,

Alan

Interesting. I always thought that it was most important to have the tweeters at ear level and that mounting the tweeters so high would pull the sound stage up towards the ceiling.

Thanks Alan - Actually - I had asked a bunch of similiar question regarding inverting the W22's - for much the same reason - bring tweeters down closer to ear level. The fact that the W22's ports would then be forever swallowing dust was one of the big reasons I decided this wounld't be worthwhile.

Thanks for the input on the M60's. I know a number of people like to toe-in there M60's, but I go with a "flat" mounting - Sounds like it'd be a scary proposition to be messing with the origional design - so I will refrain from making saw dust!

Hi Fred,

Certainly the soundstage will shift upwards, but it's the midrange driver that carries much of the important musical and audio content, not the tweeter. The tweeter largely reproduces harmonics and overtones, except for the upper octaves of the piano, violin and other instruments as well as percussion.

Everyone thinks that tweeters beam like a flashlight. Modern titanium dome tweeters and aluminum drivers have very good off-axis dispersion so you don't have to adhere to the "exactly-at-ear-level" rule. There is considerable flexibility. Besides, with surround sound home theater, it's the center channel location that's really critical. You want it as close as possible to the video display so the image and dialog/on-screen sounds are one.

Alan