Nickel on it's side demonstration...

[IWalker]

Has anyone ever heard the sales pitch about the ML descent and depth designs that having the 3 drivers operating in the alignment they're in reduces cabinet vibration such that you can put a nickel on its side on the top, and it won't fall over? Heard that at an audio store this weekend...then went home and tried it on my sub...during the opening of the opening track of Dark Side of the Moon. The heartbeat. The cone was moving like crazy...and the nickel wasn't moving. Anyone else ever tested this?

 

[Kenscollick]

A few months ago when I auditioned Summits I did notice a nickle on the sub. the salesman went through the demo with the nickle. But what is the point?

 

[MotorToad]

The point is the same as when they would do this with Honda's CBX in the showroom. The system's balanced, the same as the inline-6 engine in the CBX.

What it means in regards to the subwoofer is that the cabinet doesn't act like an out-of-phase passive radiator, nor does it muddle the bass by moving about driven by the woofer. If you put a big woofer pointing to the side in a crappy or undersized cabinet, the woofer moves one way, the cabinet the other... The woofer moves back, as does the cabinet. This damps the woofer's movement in relation to the air it's supposed to be pushing and you get muddy noise.

You could get the same result with two woofers pointing opposite directions but I don't know how well this bipolar arrangement woofer would interact with dipolar ESL panels, or if it'd even matter. Three woofers makes it about as omni-polar as I think you could want.

 

[IWalker]

That's what they'd have you believe. Any decently rigid/spiked/heavy cabinet won't have this issue (as mine doesn't) the true benefit of the ML design is that the mechnical resonances should cancel each other, thus lowering mechanical distortion. But that's harder to show than putting a nickel on the top!

 

[Joey_V]

The nickel trick worked on my brothers Promedia 5.1 subwoofer turned to the max. The nickel has an exceptionally wide edge... probably should try a penny so the most minute vibrations will topple it over.

 

[Audioseduction]

Stand a penny or a nickel on a desk and hit the top of the desk with your closed hand. You'll find it a little difficult to topple it over. Most likely many half way decent subs can pass that test.

 

[risabet]

Stand a penny or a nickel on a desk and hit the top of the desk with your closed hand. You'll find it a little difficult to topple it over. Most likely many half way decent subs can pass that test.

My cheap Velodyne f-1000 does it quite nicely!