Site Links
Howdy, Stranger!
It looks like you're new here. If you want to get involved, click one of these buttons!
Quick Links
Categories
In this Discussion
Please review the site Rules, Terms of Service, and Privacy Policy at your convenience. Rules, TOS, Privacy
Get familiar with the reaction system: Introducing the Reaction System
MCM 53-5165
In-box measurements of MCM 53-5165
http://www.mcmelectronics.com/product/MCM-AUDIO-SELECT-53-5165-/53-5165
Surface mounted in a Denovo 0.23 cubic foot enclosure
http://www.parts-express.com/denovo-audio-knock-down-mdf-023-cu-ft-mini-bookshelf-speaker-cabinet--300-7062
Mounted on center axis, about 8" or so from bottom.
Distortion, SPL accurate, 1M:
Extremely clean above 3K, and still very usable at 2K (with careful crossover work). However - that dip at ~3K is fairly pronounced and may be a turn-off for some people. It doesn't bother me since it falls right in the region that always sounds just fine with a dip. Slightly elevated top end, however, may lend some slight sizzle - but given the pretty much non-existent distortion in that area it will sound cleaner and more natural than the slight rise would otherwise indicate.
Before anyone gets too excited about that dip, however - keep in mind this is a metal dome and as such, has a phase shield implemented. So, let us take a look at the off-axis:
That is out to about 30 degrees or so - seems to be a natural for a sloped baffle.
That being said, if you use this tweeter - keep in mind that the dip at 3K will fill in off-axis, and trying to "fix it" in the crossover to get to a flat on-axis response will probably yield some pretty mediocre results so leave it in there - physics will take care of it. The top couple octaves smooth out nicely just a bit off-axis, as well. This tweeter will probably be great for speakers with a wide spacing and no toe-in.
Speaking of off-axis, some additional evidence for why we don't trust polar models:
The breakup is not predictable using standard simulators, and in this case for maximum effect will require quite a bit of tanking - or at a minimum a dedicated notch at 8500 in addition to whatever other crossover you are using.
http://www.mcmelectronics.com/product/MCM-AUDIO-SELECT-53-5165-/53-5165
Surface mounted in a Denovo 0.23 cubic foot enclosure
http://www.parts-express.com/denovo-audio-knock-down-mdf-023-cu-ft-mini-bookshelf-speaker-cabinet--300-7062
Mounted on center axis, about 8" or so from bottom.
Distortion, SPL accurate, 1M:
Extremely clean above 3K, and still very usable at 2K (with careful crossover work). However - that dip at ~3K is fairly pronounced and may be a turn-off for some people. It doesn't bother me since it falls right in the region that always sounds just fine with a dip. Slightly elevated top end, however, may lend some slight sizzle - but given the pretty much non-existent distortion in that area it will sound cleaner and more natural than the slight rise would otherwise indicate.
Before anyone gets too excited about that dip, however - keep in mind this is a metal dome and as such, has a phase shield implemented. So, let us take a look at the off-axis:
That is out to about 30 degrees or so - seems to be a natural for a sloped baffle.
That being said, if you use this tweeter - keep in mind that the dip at 3K will fill in off-axis, and trying to "fix it" in the crossover to get to a flat on-axis response will probably yield some pretty mediocre results so leave it in there - physics will take care of it. The top couple octaves smooth out nicely just a bit off-axis, as well. This tweeter will probably be great for speakers with a wide spacing and no toe-in.
Speaking of off-axis, some additional evidence for why we don't trust polar models:
The breakup is not predictable using standard simulators, and in this case for maximum effect will require quite a bit of tanking - or at a minimum a dedicated notch at 8500 in addition to whatever other crossover you are using.
I have a signature.
Comments
That dip at 3K would really be a non-issue. People worry too much about that crap. It is fairly high Q which Toole, Vance D. others all agree that a fairly sharp bandwidth (this is a hair broad) High Q (it dips fast over a a short band) dips are highly inaudible in-room. I would take the dip for the rest of its performance and if you cross it at 3K ish to a 4" mid/woof, well?