Re: McCauley M421 Quad 21" Subwoofer
I’d like to shed some light on the design intent of the M421 and its applications. I feel there may be some misconceptions about how it’s meant to be used, so I’d like to clear these up.
The M421 was designed for concert/ touring and fixed installation. While generally viewed as a large venue sub, it also has applications in smaller venues where space is limited. This is especially true in contracting where the client or architect has not planned adequate space for subs.
The M421 will replace 4 or more double 18” subs in terms of output, but takes up less space. This translates to an efficient truck pack that yields more available truck space and less occupied floor space in a venue. It’s also significantly lighter than the combined weight of 4 double 18’s.
It’s not difficult to move around, and is faster to load in and out of a venue since there are less of them. It’s also relatively easy to stack two of them. I and one other person have moved them in / out of venues and stacked them many times, and I am not superman.
They do require a minimum of an FP14000 to power, but you would need an equivalent amount of power or more to drive 4 double 18’s. I absolutely agree you cannot run an FP14000 off of a 15 amp Edison. I also agree that the 240V version of the FP14000 works better with the M421 than the 120V version does.
While the M421 can be used stand alone, we also like to mix them with our M88 double 18’s. I suggest routing the M421 and the M88s on separate aux sends and mix to taste. Here are a few real world examples to give you an idea of the ratio of M421s & M88s to venue size. We did a 2100 seat auditorium with 1 M421 placed in the center in front of the stage and two of our M88s per side. We did a concert in a 5000 seat church with 2 M421 placed in the center in front of the stage and four of our M88s per side. In both cases we had more than enough firepower for the venue.
I’d also like to comment on the settings since this was discussed above on this thread. We recommend a 24dB/Octave Butterworth High pass at 25Hz, and 48dB/Octave Linkwitz Riley Low Pass Filter at 85Hz. These settings are routinely used in the field with very good results. I encourage Bennett to try them.
Ryan Mccauley designed the M421. He’ll be posting some more technical information regarding some of the points in this thread.
Daniel Casado
Director
Engineering Support Group
McCauley Sound
