anyone familiar with Eminence MCM 55-745 12" woofer

[ceramic]

hello everyone,
is anyone familiar with this speaker model? the info I found is contradictory, no reply from Eminence (yet).

MCM 55-745 made by Eminence 1992, 12", paper cone, 8ohms;

-the magnet sticker reads 55-745; (?)21012; 8ohm; 67-92130064 G5.
-the cone stamp reads 451268-1; 12 92



I have two and would love to make an extension cab for my bass guitar (I use an Ampeg 2X10) and even use the them for music as an aux sub (using the LFE and a power amp).

Have a great day!!

 

[TBTL]

Eminence on bassreflex.de

Nominal diameter 12"
Nominal power handling 75 W
Impedance 8 ohm
SPL 97 dB (1W, 1m)
fs 59 Hz
Vas 120,4 L
Qts 0,63

That would be a large cab.

 

[ceramic]

thanks @TBTL, I am familiar with at least 2 specs for this speaker, I'm familiar with the page you referenced... it contradicts what I have found on a different webpage:

Google Groups
manufacturer/Model MCM 55-745

RMS= 100W
1W/1m= 92dB
Fs= 30Hz
Vas= 6.59cu ft (187L)
Qts= 0.38


http://www.rdrop.com/users/billmc/enclosures.txt
---SEALED BOX---
vol= 2.19
F3= 60Hz

------PORTED BOX------
vol 5.41
F3= 33Hz
Fb= 32Hz

 

[ceramic]

picture of it:

An externally hosted image should be here but it was not working when we last tested it.

 

[TBTL]

Can you measure fs? 30 and 59 Hz is a large difference so it should be easy to find which set of parameters is more plausible.

 

[bjorno]

Eminence MCM 55-745

Hi All,

FYI:

b

 

[bjorno]

Hi All,

FYI:

b

Adding some 'pesky' text...

A 12" Frame was used to Calculate the Sd Param. and Re was chosen to be 5.6 Ohm.:
In case: If Sd and Re have deviant Values: DIY Recalculate all affected Param. that are using Sd and Re to get a better total T/S estimation.
But as all Calculations here below are using Consistency Check as comparing with Qts, Vas, fs and the given SPL(All held unchanged) In prior to conducting a real T/S Measurement: There is no reason avoiding the T/S Checked Parameters in Programs like Hornresp, MJK or any other that is considered enough reliable in order to determine a Box Volume where in the Reality the Requirement of absolute Power will not differ more than a dB or so.

b

 

[ceramic]

Can you measure fs? 30 and 59 Hz is a large difference so it should be easy to find which set of parameters is more plausible.

Yes, I am inclined to go with the 30Hz after a quick voltage measurement... so one set of specs is more plausible in that sense. But it could very well be 28Hz or 35Hz hence my reason to ask the online community..

@ bjorno:
do I understand it correctly, did you just check the parameters in a software and one set doesn't make sense? Those are a lot of numbers, I am not that educated in this subject but I'm willing to learn.. ;]

 

[ceramic]

Eminence MCM 55-745 specs

I received word from Eminence Speaker LLC; this is what mr. Lucas, Design Engineer, sent me regarding this speaker, Eminence MCM 55-745:

"-pro audio mid-bass woofer, 2" voice coil and a 30 oz ceramic magnet

-T/S parameters:
*a conservative thermal power rating based on the voice coil diameter would be about 150 watts

05-RE OHMS 6.70
06-LE MH 2.25
07-QM 4.74
08-QE .420
09-QT .380
10-XMAX MM 2.80
11-BL TM 13.46
12-EFF % 1.19
13-FS HZ 30.20
14-MMS GMS 59.26
15-CMS mm/N .4687
16-RMS NS/M 2.3723
17-VAS LTRS 186.55
18-SD SCM 532.36
19-EBP 72.7
20-SPL dB 92.8"



Hope this helps future enquiries, thank you for the effort and time everybody.

I will start a new thread now, seeking advice on the type of enclosure/baffle I should pursuit given the specs of the drivers... I'll come back and add the link, feel free to join the conversation. Have a great day everyone!

 

[ceramic]

Thread related to the Eminence 55-745:
Looking for a low end low power solution using two 12” old school Eminence woofers

 

[harby]

Saw one of these for sale and ran the Eminence parameters. It truly is a bass guitar speaker, it doesn't fit many other uses.

It works best in a smaller box than earlier suggested. I came up with a 1.3 cu ft box, with a 1.8" diameter port 1" long (the thickness of a hole in good baffle).

With that, the power handling maxes out about 40W "maximum electrical power" at 60Hz or 40W pushing it over XMax below 30Hz (but bass guitarists might like making distortion...). In a ported box, this needs a subsonic filter, or an amp or instrument which doesn't make subsonics.

Makes 113dB at 100Hz with that 40 watts though... and +/- 3dB 60Hz-1kHz