2011 Silverado Crew Cab 6.2L Sundown, XS Power, Mechman Build

[SixTwoRado]

2 hours ago, guero187 said:

did you screw the amps directly to the cab of the truck?

The amp rack board is heavy duty velcroed to the back wall and bracketed at the bottom.  The bottom and middle of the amps are screwed into the amp rack board.  And for the top mounts I used rivnuts on the back wall of the truck where there is a hump that sticks out.  So nothing going through to the outside.  So the tops of the amps are bolted into the rivnuts, if that makes sense... 

Still trying to figure out what subs I should go with that will sound proper with proper box volume.  Think Im leaning towards running just two SA8V3 on the scv2000 lol.  Gonna have to keep it tuned down though.  Not sure what else to fit. Unless I make a box liked I said that has an extra portion sticking out in the floorboard area of the middle seat. 

[BP1Fanatic]

Ok, I'm not a GM guy, however that mofo looks NASTY! 

[SixTwoRado]

Alright you guys for reference here is the box I'm actually using that the E-8s sound like crap in.  https://www.soundoffaudio.com/ported-quad-8-for-2007-2013-chevy-silverado-crew/

He actually put the slot port facing out the back on mine though and I think the port itself is smaller than what is pictured on his website.  I really think the E-8s are suffering in this box because its on the small side and tuned wayyy too high.  My final wiring impedance measures out to exactly 1 ohm on the multi meter and scv2000 is tuned with the DD-1 and CC-1.  tried multiple different settings.  

So here is my last ditch effort.  Going to try and frankenstein this crappy box...  I ordered two 3" aeroports and Im going to cut out all the bracing for the slot port I can in the box and cover the slot port hole up in the back with a clean piece of abs black plastic.  This should essentially seal the box up.  Then Im going to try and fit the two 3" aero ports either on the front of the box or out the sides.  I believe it comes somewhere around 2.0 cubes after displacements.  Maybe a little less.  I know its small.  Then I'm gonna cut the aerports down to about 15" or around that.  Want to tune the box somewhere around 35hz.  

What do you guys think?  Think the 4 e8s will sound alright in a smaller box with two 3" aeros and running on the SCv2000???  Just a last ditch effort before I trash this box and sell the E-8s. 

[WalledSonic]

Sorry if I missed this, but have you tried the box sealed?  It may just sound better sealed, esp with 4 drivers in that small volume.  I would plug it and compare.  Most people (that I've seen) running under-seat boxes with 8s cant fit more than 2 with a proper port.  Maybe remove 2 of the 4 subs and put the ports where the 2 subs went?  Just spit-balling here.

Truck looks great man, I dig it.

[SixTwoRado]

Walledsonic thanks for the reply man! Really appreciate it.  Yah I think thats a really good idea.  As I said Im going to eventually sell the E8s and go to something completely different.  Trying to find a good box builder here in so cal that actually understands subs like this and can build a real box.  Im going to probably just go with two SA-8s ported and keep the amp down or Im playing with the idea to try and do just one X10 or U 10 or something point up in the middle of the floorboard with the rest of the box under the seat.  Not sure yet.

But yah I think Ill try sealing up the box first and see how that does.  Probably will seal up the port in the back with a nice cut piece of the ABS or HDPE black plastic I still have.  Im really a not a fan of sealed boxes though as far as output but it may sound better in this case.  Might try a little polyfill in the box too but it may not need it.  

If i dont like it sealed then I should be able to cut all of the port walls out of the box pretty easily with my multi tool to gain that space back.  Then I think I can just barely fit those two 3" aeroports in the middle of the box and have them both be about 15" long.  Port area and box volume will still be kind of low for the 4 8s on 2,000 watts but should be a lot better if I get the actual tuning down.  They seem to be handling 2,000 watts no problem.  Especially on regular music. We'll see.  Think two 3" aeroports is too small?

[Hellbilly429]

2 3" aeros are too small for 4 8's with that much power going to them. Even if you backed it down to 1200 watts, the port velocity would be crazy high and most likely cause port noise.

2 4" aeros with that box tuned to 35 hz looks more doable with full length 17" ports. Should get you under 30 m/s air velocity with a 28 hz lowpass filter engaged, and running roughly 1200 watts to the subs instead of the full 2000.

Rusty from DC did get away with 1 4" aero in his truck with 4 DC 8's, but I'm not sure how much power he was pushing to them and I couldn't tell you if he had any issues with it. Guess it comes down to real world testing and personal preference to get you what you want out of the box. 

[SixTwoRado]

12 hours ago, Hellbilly429 said:

2 3" aeros are too small for 4 8's with that much power going to them. Even if you backed it down to 1200 watts, the port velocity would be crazy high and most likely cause port noise.

2 4" aeros with that box tuned to 35 hz looks more doable with full length 17" ports. Should get you under 30 m/s air velocity with a 28 hz lowpass filter engaged, and running roughly 1200 watts to the subs instead of the full 2000.

Rusty from DC did get away with 1 4" aero in his truck with 4 DC 8's, but I'm not sure how much power he was pushing to them and I couldn't tell you if he had any issues with it. Guess it comes down to real world testing and personal preference to get you what you want out of the box. 

Yah I pretty much figured the two 3" aeros would be too small.  Only (very roughly) about 7 in.^2 of port area per cube. I may still try them before scrapping the box.  Unfortunately theres really no way to fit the 4" aeros in the dimensions of the box, unless I maybe made custom ones but dont feel like putting that much effort into this box.

Probably just going to seal it up for now and see how that sounds.  I am giving each sub 500 watts but it seems like they are laughing at that even though they are rated at 300.  Im not blasting it all the time in this truck.  The few times I have pushed it at full tilt for a long time on heavy bass tuned songs they seem unphased, didnt get too warm.  I understand youre saying turn the power down for port velocity reasons though.  

Im really leaning towards just getting rid of these E-8s.  Not working for my setup.  Id really like to run just one big 1500 watt sub somehow.  

What would you guys vote for... Two sundown SA-8s, one X-10, or one of the new U-10s?  I used to have one SA-12 ported in my old truck on a 1,000 watts and loved that thing! It was in the proper box for sure though.  

Im thinking of trying to do a single x-10 or u-10 in a box sort of shaped like the "T" block shape in the tetris game, like below haha.  So the big 10 would be facing up where the middle back seat passenger feet would normally go.  What do you guys think of that idea?  The rest of the box would still be wedge shaped under the seat with one big port out the side. Not sure how the sub would act sort of being in a super small enclosure but then opening up in to the big main part of the enclosure??

[Hellbilly429]

I think as long as the airspace you provide doesn't narrow down to less than or equal to your port area, then you should be fine. Are you stuck on Sundown as your only options?

[SixTwoRado]

3 hours ago, Hellbilly429 said:

I think as long as the airspace you provide doesn't narrow down to less than or equal to your port area, then you should be fine. Are you stuck on Sundown as your only options?

Roger that.  That makes sense.  Might be possible, Im going to have to go to the drawing board and figure it out.  Im open to suggestions of course, but Sundown has never let me down, I've always been impressed.  Plus the rest of the audio in the truck is sundown lol.  What did you have in mind?  Id definitely be open to suggestions for two 8s that can fit easier than the X-8s from Sundown but offer more than the SA-8s?   

Anyone else here running a single sundown U-10?  I could fit one of those easier than an X-10 and they rate them at 1500 watts.  Plus I like the sound of all the SA subs already. 

[Hellbilly429]

Don't get me wrong, I love Sundown subs and have had 2 myself. The DC level 4 subs are rated at 1400 watts and require less airspace than most subs in their size and power range. I've got a level 4 15 from previous build that I loved so much I went and bought a level 4 12 for my new build, lol.

The SD-8 I'm running in NY girlfriend's car takes very little space and sounds decent though, just not probably enough for what you looking for.