Are MK's Right For Me?

[Skizza]

Hi all, I'm thinking about getting some SI BM mkIII's but I have a few questions hopefully you can answer. I'm looking to put two 12's in fiberglass pocket enclosure on my dodge magnum. Obviously I will already be limited in terms of bass, but given my enclosures and amp specs (seen below), would you recommend SI BM mkIII's over Realm LFT12D4F, Earthquake SWS-12, and MTX Thunder Thin 12"? How do the mk's measure up to those in terms of poundage? I want something that sounds good, but want to maximize bass also (I know, cake and eat it too).

Here is the info about my setup:


Enclosure Specs:

• Product dimensions: 750x450x250 mm.
• Appr. Airspace: R- 0.65 cu. ft. L- 0.71 cu. ft.
• Mounting Depth: R- 7.2 in. L- 8.1 in.

Amp Specs:

• 1000 watts x 1 @ 4 ohm mono
• 1500 Watts x 1 @ 2 ohms Mono
• 2060 Watts x 1 @ 1 ohms Mono
• Variable Low-Pass Filter: 50Hz - 150Hz @ 24dB/Octave
• Variable Subsonic Filter: 15Hz - 40Hz @ 24dB/Octave
• Variable Bass Boost @ 45Hz: 0 - +18dB
• Variable Phase Shift: 0 - 180°
• THD: <0.08%
• Signal-to-Noise Ratio: >100dB
• Frequency Response: 5Hz - 250Hz
• Input Impedance: 10kO
• Input Sensitivity: 300mV~8V
• Tiffany-Style RCA Jacks
• Parallel Line-Out RCA Jacks
• MOSFET High-Speed Switching Power Supply
• Heavy 4 oz. Pure Copper PC Traces at All Preamp & Amplification Stages
• Internally Mounted Fan-Cooled Power Supply
• Solid Brass Nickel-Plated Terminal Blocks (4-Gauge Power, 8-Gauge Speaker)
• 4-Way Protection Circuitry: Thermal, Short Circuit, Overload & DC Offset

[Electrodynamic]

The thing to keep in mind is that the BM mkIII is a top-notch SQ subwoofer. It was not designed with perceived output being the number one goal. The BM mkIII is extremely linear, VERY low distortion, and plays over a super wide bandwidth. Low distortion, linear topology (BL), subwoofers do not sound like other conventional subwoofers. They don't have that "stressed" or "broken in" sound as the volume gets turned up. A BM mkIII can be doing a 133 and sound like another driver that's only doing a 127 because of the extremely low distortion, as distortion is perceived as loudness to the human ear.

The box volume you're working with is also a bit large for a BM mkIII. See our FAQ thread and you'll see box volume vs power handling in there. And with the depth of your enclosures (close to 8"), you can almost use any subwoofer(s) you want...besides the low internal volume issue.

Oh, I forgot to add that the BM mkIII probably has 1.5 to 2 times the displacement as the other subwoofers you mentioned. Most shallow subs have 5-7mm of Xmax. The BM mkIII has 14mm of Xmax.

[hobie1dog]

When you made the comment, " I want something that sounds good", then you owe it to yourself to get a BM...it plays loud and deep too. Has alot less distortion than the other woofers listed.

[Skizza]

Originally Posted by Electrodynamic

The thing to keep in mind is that the BM mkIII is a top-notch SQ subwoofer. It was not designed with perceived output being the number one goal. The BM mkIII is extremely linear, VERY low distortion, and plays over a super wide bandwidth. Low distortion, linear topology (BL), subwoofers do not sound like other conventional subwoofers. They don't have that "stressed" or "broken in" sound as the volume gets turned up. A BM mkIII can be doing a 133 and sound like another driver that's only doing a 127 because of the extremely low distortion, as distortion is perceived as loudness to the human ear.

The box volume you're working with is also a bit large for a BM mkIII. See our FAQ thread and you'll see box volume vs power handling in there. And with the depth of your enclosures (close to 8"), you can almost use any subwoofer(s) you want...besides the low internal volume issue.

Oh, I forgot to add that the BM mkIII probably has 1.5 to 2 times the displacement as the other subwoofers you mentioned. Most shallow subs have 5-7mm of Xmax. The BM mkIII has 14mm of Xmax.

I'm back! I read this before as no, they are not right for my application, but people keep telling me Mk's MK's. Honestly I didn't really understand the box volume vs. Power handling thread so I'm back with more questions. Just to be clear, in your opinion I should go with a normal sized (non shallow mount) sub made for small enclosures? Sounds like my enclosures are like a "tweener", to much airspace for MK's, but too little for a lot of non-shallow subs. If MK is not for my application, can you make any recommendations?

Thanks again.

[Electrodynamic]

Originally Posted by Skizza

I'm back! I read this before as no, they are not right for my application, but people keep telling me Mk's MK's. Honestly I didn't really understand the box volume vs. Power handling thread so I'm back with more questions. Just to be clear, in your opinion I should go with a normal sized (non shallow mount) sub made for small enclosures? Sounds like my enclosures are like a "tweener", to much airspace for MK's, but too little for a lot of non-shallow subs. If MK is not for my application, can you make any recommendations?

Thanks again.

Well you have the depth available for a "normal" depth subwoofer but the enclosure volume is still pretty small. A BM mkIII will work in your application but you must run lower power on them (250 to 300 watts each) due to the extra enclosure volume above what is recommended. The good thing about the extra enclosure volume that you have is that they will play lower and not require additional power to reach a certain output level.

Again, the BM mkIII's are not a power hungry "I must put recommended power on them to get them to move" subwoofer. They are perfectly happy with 250 to 300 watts each. In fact, there is a customer that supplied pictures and a guide of his install where he is using a JL 250/1 on his BM mkIII and absolutely loves it.

Keep in mind that power handling is not a power requirement!