Yes, the difference over coaxials is significant, certainly enough to justify throwing them in your existing cans.
Was the 6 pack a noticeable improvement? Yes, it definitely was. Hard to really quantify as I never really focused on a "before vs after".
I've been told that the 6-pack is comparable to the sound output of a pair of Rev8's or the XM9's. They don't get the lower midbass tones that the larger drivers do, but they do pretty darn good. the magnet on the back of the midbass driver is the same as the larger 8" drivers and there's no tweeter in the way. so there's actually extra surface area relative to traditional HLCD's with the horn in the middle.
The 4 speakers run at 4 ohms and the 6 speakers run at 2 ohms. because the horn takes the high frequencies, and the midbass takes the lower they don't 1/2 the resistance like you might think. It's similar to how component speakers or even coaxials work. so adding the extra pair of midbass takes it from the 4 ohms to the 2 ohms.
I have it wired pretty simple: 2 channels. wired in parallel. For this reason, I'm using a 2 channel amp for my tower speakers so I have the channels stable at 2 ohms. I am using the PPI P600.2
My tower was actually wired with the tower speakers on a 4 channel amp (not bridged) so by using a 2 channel amp, that actually freed up a pair of conductors on each side that I was able to repurpose for Tower Speaker LED's. Love how it worked out. I also put polyfill in with the midbass.
There's nothing wrong with doing it in phases, like I did. start with the 4-pack, see how you like it. it'll most certainly be a solid improvement over coaxials for a pretty modest investment. And then you can decide if it'd make more sense to go with a 6-pack or to bite the bullet and go to 8 or 10" big boy HLCD's.
I really do appreciate the headroom that I gain by only having the 6.5 cans. Sure, someday I'd love to have some Rev10's or something, but they are HUGE and that's something to factor in, not to mention the price of that kind of upgrade.
I'm pretty happy with mine for a good mid-level system. it's hard to beat for the money.
2008 Moomba Mobius XLV. Monster Cargo Bimini, WS Rev 410's, Polk Cabins, 3 Infinity Subs, PPI amps, WS420, Exile BT, upgraded ballast pumps, up to 3,500+ pounds of ballast, Blue LED's...
1992 Supra Sunsport. **SOLD** 2k pounds ballast, Surf System, Blue LED's everywhere, decent audio system.
Tow Rig: 2013 F150 Ecoboost FX4 (wife's rig) Other money pits include:1998 BMW M3 Cabriolet, 2009 Audic A6 Avant 3.0T, 2005 Kawasaki ZX-6R 636.
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