95Honda

Power handling has nothing to do with output, at all.

No blackout, you can't see anything, it matches all the other vents... To give you guys an idea of how efficient the sub stage is, unless I have the gains on the sub amps at 1/4 or less, the receiver sets the subwoofer to maximum attenuation during the auto calibration with the microphone, lol... I did have one problem I had to sort out, there was some noticeable 60Hz hum caused by a ground loop, and the fact that none of the Pioneer gear is grounded, lol... I ran a #8 ground wire to bond the receiver and sub amps downstairs, zero hum now!

I haven't modeled, but that sounds big enough... I have installed a few of those exact drivers...

All done! Bass is amazing, zero peaks/dips, just solid low end. It turned out more efficient than I thought it would be. With drivers mover a millimeter or two maximum, the output levels are shaking the walls upstairs. No vent noise/chuffing that was obvious. I did run a flush cut trim bit on both ends of the feed to the vent so there aren't any mismatched wood joints... The surrounds sit about 1" behind where the finished drywall will hang, so between that and the 3/4" for the grill frame clearance will be perfect... The grill will be 36" x 60" and will be stretched with white acoustic cloth... I always liked IB, it has just been forever since I have been able to enjoy it. Everything turned out great, I wouldn't change a thing...

I have hung on to the XXXs for almost 10 years. They are still in perfect shape and have been waiting for something like this... Their Qts is really too high for vented alignments, so sealed or IB is the goign to be the trick...

Manifold all done. It was a bitch getting it up there myself! I'll mount the woofers Sunday, I want the glue to cure all night. Hurricane nuts and 10-24 allen head cap screws to secure the drivers...

That is what it is, I removed the flaps on the back. Whole idea was to keep everything out of sight, I think it will do just that! I have a good feeling I am going to have some serious low end...

No turning back now! I ended up going with a 12" x 6" vent, it should keep compression at a manageable level... I will build the manifold Saturday and hopefully have everything mounted by Sunday. Signal cables are already run. I will just place the amplifiers up on a shelf inside the sofit framing until I get everything done.

They used to make a lot of them, until class D (and Tripath for a while) became so cheap and reliable... MTX and a few others still make them (last time I looked), but they are rarely over 1000 watts due to cost vs. class D...

The class Ds will sound different, but all the other factors in the signal chain will have drastically more effect on the perceived sound quality, assuming the amp isn't being driven into hard clipping. Where you will hear big differences between amps is when they run out of gas and start clipping... No prob on the info, that is why we are here.

If it is the UK, it would likely be in pounds, they are worth 1.5x the US dollar... As far as THD, that is hard to use as a way to compare class D. If you look into into how a class D works it it is a bunch of really fast pulses that are varied and then filtered, so they inherently have more THD than almost any A/B... If I saw a THD rating of 1% on a class D I wouldn't even flinch, that would not be a good rating on A/B before clipping... Efficiency is very similar between amplifiers. They all have similar switching power supplies and output stage topology. Most of the biggest differences you will see advertised is subjective as it is hardly ever measured in a standardized way... BTW, I think I paid $400 for the last Md2d refurb in 2007... My brother is still using it to this day without issue...

Again, I am talking newer class D amps, you are talking vastly different topology... The older class A/B were extremely different. Output topology varied greatly from amp to amp, as did power supplies. Dampening was all over the place and greatly influenced driver control... The biggest sound difference you will hear with a current class D is having one that has enough power to not run out of gas at your chosen output level versus one that doesn't...

how was the power of them? did they meet your expectations? how did they sound? please, man, i need details! They are class D, so they sound like most other class Ds. The differences you here on the sub stage between most class D amplifiers is due to everything but the amplifiers themselves. Don't misunderstand what I am saying, there are differences, but 99% of the sound you hear is determined by everything before and after the actual amplifier stage... They are a 2Kw amp, so they will power any sub made. The last one drove an RE SX 15 to full output before audible amplifier clipping, but honestly, that took less than 1Kw in the alignment I was running...

I have used a couple of the refurbished Md2d amps, they worked fine and were cheap...

You can run that sub with any amplifier. If you are wondering if it is enough power to get full output from the sub, you will only know if you have the enclosure designed...

I would also try and eliminate the remote turn on circuit by jumpering your battery + to your remote turn-on input of the amps and let it rip for a while to see if they shut down... Like everyone else has said, it really sounds like a wiring/DC supply issue...

I built some enclosures out of 1" acrylic (plexiglass) in the mid 90's for some Focal woofers in a car audio install. It seemed to sound fine, but is a lot of work, took forever, I ruined a ton of material and spent hours buffing out scratches... It was also expensive then, I can only imagine now... I really really want to swap my basket out for a TI on my btl when I eventually recone it, would you mind if I messaged you about the details of building a plexi box when I do so? Sure

I built some enclosures out of 1" acrylic (plexiglass) in the mid 90's for some Focal woofers in a car audio install. It seemed to sound fine, but is a lot of work, took forever, I ruined a ton of material and spent hours buffing out scratches... It was also expensive then, I can only imagine now...

MDF dust is terrible... It also isn't supposed to be good for you over the long run... I know I have been breathing it for at least 20 years... MDF is cheap, also... We tend to forget that fact...

Hardwood, besides not liking to be attached at more than one axis and cracking, has too many uncontrolled resonant modes to use as a loudspeaker enclosure material. Successful solid wood cabinets have used the butcher block approach to alleviate the two previously mentioned problems, look at Sonus Faber and you will see what I am talking about. Acoustically, MDF is the best choice of materials in this thread. High quality plywood is the strongest... So choose you poison...

Are you talking Cherry, Poplar or Walnut plywood?

Kind of... They will possibly (very likely) go below one ohm at one point, but it is very narrow in bandwidth... You need to know where if you are truly worried about smoking your amp... At the point where reactance is null, the sub (system) impedance will be almost DCR, plus whatever series resistance the wiring you have is. You will see this point when you model... I would caution use of Youtube as a technical reference...

If you model your enclosure and look at the impedance plot you will see what you amplifier will see and know if you will be too low...

That is the DCR rating, not the impedance. There is no such thing as "box rise", only an impedance curve as it both rises and falls... You can model or measure to see what load your amp sees. The DCR has little to do with the overall load, the enclosure plays the major role....

Save the powerpoint as a Jpeg and then upload that...