surface mounting 10.2

[soundnovice]

this topic might have been discussed somewhere else, but anybody tried surface mounting alpair 10.2 in pencil or vented bookshelf designs. does it effect the sound quality considerably?
not flush mounting will save hell lot of woodwork for me!

[Scottmoose]

It won't do the sound quality any favours, and probably look daft too. This is one of those cases where a bit of effort expended in construction is worth it. If you're really struggling, you could always build up a front baffle with thin layers of cork or similar, although admittedly you'd have to like the look of cork (I do as it happens).

[fastbike1]

With a router and a circle jig it's no more than 30 minutes for a pair including a test cut. An hour if you haven't done it before.

Originally Posted by soundnovice

this topic might have been discussed somewhere else, but anybody tried surface mounting alpair 10.2 in pencil or vented bookshelf designs. does it effect the sound quality considerably?
not flush mounting will save hell lot of woodwork for me!

[TiMBoZ]

I don't think it makes THAT much difference. Especially for wide range. How much it matters soundwise might also depend on the baffle width. How much the baffle extends out past the driver frame. There are commercial designs where the woofer isn't flush mounted into the baffle face but the tweeter is. Others where all drivers are mounted flush within a large baffle. B&W have tweeters mounted above baffles like antennas etc. This would be factored into the XO I guess. But I think if it was really critical, I think you would see consistency ie: all baffles would look approximately the same, which they don't. If you made otherwise identical but one flush mounted set of pencils and a non flush mounted set of pencils, would one hear the difference? Could one measure it?Maybe off axis in a perfectly tuned room. Personally, I wouldn't sweat it. If you stick an A10 on half decent box, there'll be bigger fidelity issues to worry about. Like your room.

[Scottmoose]

Unfortunately, you would hear (and measure) it quite easily, particularly off-axis. With the thick frames on the MA drivers there is a severe surface discontinuity if not flush mounted. Sorry. As the world's worst woodworker, I'd love it if it were otherwise, since, odd looks aside, I'm in favour of anything that makes life easier, but alas it does make a difference, and not a small one.

You don't get consistency because it depends on circumstances and the drivers in question. Especially with multiway designs.

With that said, the room does indeed dominate in the lower registers with a point-source design. Higher up, again, depends on the speaker in question.

[TiMBoZ]

You don't get consistency because it depends on circumstances

What circumstances?

So if you don't 'flush mount' an A10 - it's worthless, broken?

[chrisb]

Originally Posted by TiMBoZ

What circumstances?

So if you don't 'flush mount' an A10 - it's worthless, broken?

he didn't say that - you could just expect (and most likely easily measure) greater degree of higher frequency diffraction artifacts

[silverhairbp]

Everybody has their own tastes. For some, surface mount might be an acceptable arrangement. For others, it might require a flush mount in a sealed cabinet of optimum volume with multiple driver braces and carefully beveled cabinet edges at just the right angle.

Mount the driver however you want and listen to the results. If it seems lacking, try a different arrangement, flush mount, change the cabinet stuffing, the port opening, yada, yada, yada.... There are a lot of options that are not hard to test.

That's what's nice about this hobby. Experiment with whatever you want to try. It's not like building an airplane.

[Scottmoose]

Quite. But to avoid diffraction effects from discontinuities at the edge of the frame, it has to be flush mounted. Fact.

What circumstances?

The type[s] of drive unit involved, the shape and size of the frame (and whether they were designed for flush or surface mounting), their dispersion characteristics / polar response / on / off axis FR, crossover frequencies & orders where relevant and a host of other factors you presumably don't need me to list.

So if you don't 'flush mount' an A10 - it's worthless, broken?

Where on Earth did I say or imply that? Don't be silly. I simply pointed out the fact that all of the MA drivers are designed for flush mounting and that this is required to avoid measureable and audible diffraction effects. That's just the way it is.

[TiMBoZ]

does it effect the sound quality considerably?

I think was the question.
There are a gazillion different interpretations of baffle/drivers in situ. Your point makes mountains out of molehills IMO.