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For me, I'm looking whether the amplifier has enough output to push these drivers sufficiently. I'm also looking for how it handles delivery of power over difficult passages without needing to activate cooling fans. Any turn on/off thumps in my system. How much current is drawn and if it has an negative impact on anything on the same circuit and vice versa. Practical stuff really.

Given the frequencies I'm using it for now, sound quality should be adequate. But I'd like to also be happy with its transparency if I decide to use it in a different application (e.g. powering large front mains).
I was gonna say, short of bringing your completed subs and a store that would allow you to "audition"....

Crown XLS fans I've not ever been able to hear without putting my ear literally up to the unit. They're very quiet, never heard them go into a louder mode but if I'm listening to something at high volume, doubt it would be noticeable if it happens at all (it may be a two speed fan setup, don't know as it always seems the same level when I've bothered to put my ear up there). I've not heard of anyone mentioning the fans as being a noise issue. Mine are in the same open stand as my other gear in my living room for the subs, in the small bedroom setup as 2ch my disc player is noisier and its not bad.

I have used them for mains, did that for quite a while before I built my subs. The background noise related complaints I know of were from a few with very high sensitivity speakers (like 110dB), in a quiet room, of some background hiss. I've not had a problem but I don't have high sensitivity speakers (87 dB for me at the time for mains). I've also got one setup (I have four of these amps total) with some 90dB speakers in a 2ch setup, no hiss issues. No turn/on/off thumps.
 

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Also, how are you planning on wiring the subs? Which voice coil version did you get?
 

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Discussion Starter #23
2ohm version. I'm wiring them in series (to present a 4ohm load) using 8ga cable between the coils and out to the speakon connectors.
 

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2ohm version. I'm wiring them in series (to present a 4ohm load) using 8ga cable between the coils and out to the speakon connectors.
I was going to say the XLS, although capable of 2ohm, aren't as capable at that impedance as others (but the bridged mode at 4 ohm I've seen no issues with), also depends on your ULF goals to an extent (as there is a built-in roll off below 20hz on the Crowns, altho they do fine down to around 10hz per many reports). Then again a Speakerpower amp, if within budget, would be awesome. Don't know if you saw this thread but it may be of interest http://www.hometheatershack.com/forums/subwoofer-amps-high-pass-filters/142826-master-list-hardcore-ish-amps.html
 

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Discussion Starter #25
Very good link, thank you! I've been doing some research on models which do NOT have a high pass filter as I do want response near 10Hz. That's why I've been avoiding amps with DSP's and such.
 

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Very good link, thank you! I've been doing some research on models which do NOT have a high pass filter as I do want response near 10Hz. That's why I've been avoiding amps with DSP's and such.
You don't need the dsp for eq purposes? What will you use otherwise?

ps you know 8g for internal wiring over such a distance is totally overkill? Maybe for a significant distance from amp to sub....
 

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Discussion Starter #27
I plan on using the room correction built into the Emotiva XMC-1 (Dirac Live Full).

I agree it is overkill, but I want a lot of cable to fill in the posts as much as possible and I have a lot of cable left that I want to use.
 

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Discussion Starter #28 (Edited)
Got one enclosure built and starting on the second one's outer walls.

I wanted to measure to see where I am on weight for just the inner enclosure. This measurement is for a 14" cube made from birch with one brace in it...

 

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Discussion Starter #32
Update for tonight: done with the building phase. Routing of all needed edges are complete and the holes for the connectors are drilled. I put them on the side so I have the option to move the enclosure closer to a wall.

Lessons learned: do the routing outdoors! Every inch of my garage is covered with dust. I'll be using my air compressor and my trusty shop broom in the morning:(
 

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Discussion Starter #33
With the garage now clean, I can work start to prepare for the grills. I see many people didn't make grills for their 'high surround' subs, but mine will be located near foot traffic so, for me, it's a must.

I'll hold off on building it until I see how far they extend, but the provisions for the grill needs to be made now. On my current sub, two of the pop-in grommets failed and I wanted this design to improve on them. I decided to use magnets.

K&J Magnetics model number RX033CS-S

They have a 20lb pull force in my application to the should prevent vibrating the grill on the subwoofer's face and from easily movement if bumped.
 

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Discussion Starter #34
So I used a 1 1/4" hole saw. Drilled in a little bit, then stopped, removed the pilot bit, then drilled in further-enough to use a flathead to pry out the center chunk. Placing the magnetic in, I wanted it to be just below the surface so that the body filler will skim its top, giving me a smooth sandable surface.

I attach the magnetics using glue and a dry wall screw. Submerged it in glue so it's just under the level of the face.












 

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Cool idea for sure, but I would give that glue a week and see how much it shrinks and cracks before skimming bondo over top. Just in case. I always use lepage carpenters glue and the puddles always curl and crack.
 

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Discussion Starter #36 (Edited)
Completely agree. Just in the 5 hours of dry time today, the glue level had dropped .



I'm in a holding pattern anyway since my sanding discs won't arrive for another week so they'll be plenty of time for drying.

Plus it's 47F here this weekend; too cold to spread any filler.
 

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Discussion Starter #37
Oh, before I forget....I weighed one of the completed enclosures today (bought a scale) and it's exactly 40lbs. 0:)

The driver is listed at 78 lbs.
 

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Oh, before I forget....I weighed one of the completed enclosures today (bought a scale) and it's exactly 40lbs. 0:)

The driver is listed at 78 lbs.
LOL wonder if you're going to be able to "walk" that sub....
 

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Discussion Starter #39
LOL wonder if you're going to be able to "walk" that sub....
You know as I read more build threads on the forum, my duo is pretty lightweight! There's one thread over in the ported section that had an enclosure weigh 270lbs WITHOUT the driver! I would struggle to get that up the stairs:crying:
 

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You know as I read more build threads on the forum, my duo is pretty lightweight! There's one thread over in the ported section that had an enclosure weigh 270lbs WITHOUT the driver! I would struggle to get that up the stairs:crying:
I used plywood so as not to have as heavy an enclosure as with mdf....without rubber feet they walked a bit. I still move them around separately (box vs driver) and assemble in place. I went with magnets both in the grill frame and on the box, that proved too much magnet, now just use the magnets in the box and a screw in the grill, holds fine. K&J does have a nice assortment to choose from....
 
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