looking for MCM 55-1855 graphs

[sberube]

Does anybody know where I could find (at least) spl graphs for the MCM 55-1855 drivers? I know John "Zaph" has used it in a design (but discarded it to use a seas driver instead) and planet10 has a page for this driver, but the graphs have a low resolution. And the manufracturer doesn't seem to have more than thiele params.

Any help would be much welcome.

[Zaph]

Originally posted by sberube
Does anybody know where I could find (at least) spl graphs for the MCM 55-1855 drivers? I know John "Zaph" has used it in a design (but discarded it to use a seas driver instead) and planet10 has a page for this driver, but the graphs have a low resolution. And the manufracturer doesn't seem to have more than thiele params.

Any help would be much welcome.

Hello,

I don't have that project posted anymore but I still have the data. By memory however, I can tell you the response is smooth up to 2Khz where it drops off pretty quick. The breakup node is at 8kHz and is relatively tame, enough so that a notch filter is typically not needed on this driver. I don't think I'd cross over lower than 2kHz.

I can post a curve when I get home from work today.

I have a brand new pair of these which will be part of a comparison of 5" $15 woofers, which I will do when I get some time. There are 5 pairs of woofers in this test:

MCM 55-1855 Aluminum cone
MCM 55-1505 Fiberglass cone
Dayton 295-301 Coated paper cone
Dayton 295-330 Aluminum cone
Silverflute W14 Wool cone

It should be interesting to see how the cheap stuff compares.

[Zaph]

Actually, I have one on a speaker junk backup cd here at work. This appears to be an in-box curve with the baffle step peak showing up in the 1kHz range. I didn't take this curve, as I don't own CLIO, but by memory it looks accurate. According to the file date, this is from 2002. Later on I will be able to confirm that the current production looks the same.

[sberube]

Cool, Thanks alot man. I really appreciate the info.

BTW, I've noticed a model you've built in the archive section of your website using two MCM 55-1855's and a seas 27TFFC. If you don't mind, I'd really like to have a peek at your x-over as this is the exact configuration I'm looking into building as a sealed center channel.

If you could email me your design, I'd be much appreciative.

[Zaph]

my email address is threeXYZpoint14159265358979323846@yahoo.com. Remove the X, Y and Z. Then I'll send back a return email with the design and some additional advice for center channel usage.