Hi,
Has anyone seen that drole layout : S300 MTM
If I can understand why it is usefull to make closer both woofers in order to a better center to center for higher frequency beginning of the honney comb effect, however I wonder about the fullly offseted tweeter in between as well as adding two tweeters for a tweeter array. Proac and Living voice offseted sligthy the tweeter in their MTMs but never as far as M&K Sound breaking the vertically mid to tweeter layout "rule"!
What if suppressing the two top and bottom tweeters ?
How can be horizontal response with such fully offsetted tweeter if all the centers to centers are not 1/4 WL but 1.5 WL due to the size of drivers and tweeter face plate ?
Thanks for your thougths
Has anyone seen that drole layout : S300 MTM
If I can understand why it is usefull to make closer both woofers in order to a better center to center for higher frequency beginning of the honney comb effect, however I wonder about the fullly offseted tweeter in between as well as adding two tweeters for a tweeter array. Proac and Living voice offseted sligthy the tweeter in their MTMs but never as far as M&K Sound breaking the vertically mid to tweeter layout "rule"!
What if suppressing the two top and bottom tweeters ?
How can be horizontal response with such fully offsetted tweeter if all the centers to centers are not 1/4 WL but 1.5 WL due to the size of drivers and tweeter face plate ?
Thanks for your thougths
Also : 3 tweeters have sligth magnitude differences due to both production but also different position on the "x" axis due to the array ?! Is not that giving a confusing treble reproduction in that area where ears are so.... picky ? That speaker has a 1500 hz cut-off.
indeed impossible above 300/400 hz cut-off with such 6" midwoofers... and maybe the woofers are not in parrallel but in a 0.5 way arrengement like Barefoot https://barefootsound.com/micromain27/
Which is more intriguing me is the tweeter full offset in the vertical plan.
...VS classic MTM arrays (or close à la Living Voice)
Which is more intriguing me is the tweeter full offset in the vertical plan.
...VS classic MTM arrays (or close à la Living Voice)
The angle and distance variation are negligible at listening distance.
I read the linked page and could not see their reason for using multiple tweeters, what am I missing?
A vertical array of three tweeters creates a lot of vertical directivity. This was popular in home theatre speakers about a decade ago, I think? ... I believe there was vertical directivity spec (Dolby, THX or some such) that could only be reasonably met with a vertical tweeter array... any one recall the details ?
j.
j.
Right, though don't remember the details beyond like with high aspect ratio (CD) horns we only want to cover (isolate) an audience from any room reflections.
Seems odd to me cause one of the reason people use MTM is to reduce vertical directivity. Does an array produce the same behavior? My basic understanding is the arrays are used for bass behavior only ? What is meant by "vertical directivity" please ? Foccusing sound or the opposite : adding more energy off axis for soundstages reasons like avoiding MTM effect and let the room creates its soundstage VS more clarity with focused treble (horn, wave guide, MTM (for that last just for reduce floor to ceilling reflexion) ?
one of the reason could be also to reduce distorsion due to the 1500 hz x-over, maybe. Or to reduce the crossover slope because more x-max margin ? But seems a too much expensive solution for a brand ? While they maybe need 3 tweeters to acheive enough spl for the THX certification ?
The few loudspeakers I remember having several tweeters were from Sony or huge Dynaudio flagship.
Now if offsetting the tweeter(s) or not is non important because all is merging in the far field at listenning distance, say 10 feets, then having the woofers closer to each other is an advantage to increase a little the crossover frequency with the tweeter or the honey comb fitering is just about the woofers spacing in a MTM ?
I tried X-Dir to mimic MTM and also Edge with two woofers only with mic at 10 feets and off axis and I can't see any clear rule pops up !
one of the reason could be also to reduce distorsion due to the 1500 hz x-over, maybe. Or to reduce the crossover slope because more x-max margin ? But seems a too much expensive solution for a brand ? While they maybe need 3 tweeters to acheive enough spl for the THX certification ?
The few loudspeakers I remember having several tweeters were from Sony or huge Dynaudio flagship.
Now if offsetting the tweeter(s) or not is non important because all is merging in the far field at listenning distance, say 10 feets, then having the woofers closer to each other is an advantage to increase a little the crossover frequency with the tweeter or the honey comb fitering is just about the woofers spacing in a MTM ?
I tried X-Dir to mimic MTM and also Edge with two woofers only with mic at 10 feets and off axis and I can't see any clear rule pops up !
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No, I wouldn't say this. Back in the day the D'Appolito configuration was seen as a way to reduce lobing through the cross, making the vertical wider. The more recent talk of narrow vertical is as a caution, since the woofer spacing can be a design limitation.
In any case, using three tweeters this way produces some complex lobing in itself. That's not to say it doesn't sound OK, but it may not be a choice some of us (who do not have imposed requirements) would make.
Right, with my lack of technical knowledge way back when and sometimes still do when appropriate to post a response, I drew sound 'bubbles' at different frequency diameters to 'see' the theoretical patterns to determine driver size(s) based on theoretical XO points that would meet my target polar responses.
well they talk about the tweeters array in page 8 but the writting before about phase alignement with Z center near the woofers surround and no difraction because woofers are recessed is odd to me.
Is the soundstage suffering of horizontal off axis tweeter on a baffle because having ourselves 2 ears on the same line ? Made for being more focussed on what happenning in the horizontal surrounding of our body (threats) ?
Or just the designers put the drivers in a vertical line to find a better radiation patern ?
Or just the designers put the drivers in a vertical line to find a better radiation patern ?
ahaha ! 😆
Have you been trying to put a tweeter and a midwoofer in the same horizontal axis in your long audio diy journey ?
Have you been trying to put a tweeter and a midwoofer in the same horizontal axis in your long audio diy journey ?
You can get an idea of how this arrangement might perform in this review of an older sibling:
https://www.audiosciencereview.com/forum/index.php?threads/m-k-s-150thx-speaker-review.45586/
https://www.audiosciencereview.com/forum/index.php?threads/m-k-s-150thx-speaker-review.45586/
That's not an MTM, that's a two-way speaker where the midrange array is designed to approximate a line source down to about 1khz, and the tweeter does like wise.
That's different than an MTM; in an MTM, the midranges approximate a line source while the tweeter is a point source.
If you get the spacing relatively tight on an MTM, you can approximate point source behavior all the way through the midrange.
One of the fundamental challenges with building any type of array is handing off from one frequency range to another.
Also, the power tapering used in the M&K speaker is perfectly valid, there are a lot of good reasons to power taper.
That's different than an MTM; in an MTM, the midranges approximate a line source while the tweeter is a point source.
If you get the spacing relatively tight on an MTM, you can approximate point source behavior all the way through the midrange.
One of the fundamental challenges with building any type of array is handing off from one frequency range to another.
Also, the power tapering used in the M&K speaker is perfectly valid, there are a lot of good reasons to power taper.