DiyMobileAudio.com Car Stereo Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
2,298 Posts
Discussion Starter #1
I've got a 6.5", 4", and tweeter in each of my front doors, I'm swapping out my current 6.5s for Peerless SLS 830946s when they show up, and I'd like to fix another issue while I'm redoing my baffles for the slightly larger midbass drivers- My 6.5" and 4" are both running IB, and I'd like to enclose one of them to keep the rear waves from interfering with each other.

Madisound recommends a vented .4 cube enclosure for the SLS, but that's for an F3 of 44Hz and these won't be playing below 65 or so.

The 4" might be easier to enclose but I don't know how large of an enclosure to make for a dedicated mid- playing roughly 300Hz-3.3KHz.

Would it be better to keep the SLS IB, or the midrange IB??

I'm tempted to try XTC foam baffles for the 4"s, but everyone seems to hate those. Most of the negatives I've heard about the XTC baffles have been about losing bass response though, which won't be an issue with a 4" mid.

Specifics:
'04 Tahoe.
a/d/s/ PX tweet (minus housing).
a/d/s/ 344is midrange.
(currently) a/d/s/ 336is 6.5", soon to be replaced with Peerless SLS 6.5".
Somewhat deadened doors.

Visual:


Thanks in advance!
-Cory.
 

·
Registered
Joined
·
1,146 Posts
The foam baffles aren't really an enclosure.

I think if your rear waves can't get back into the car you could leave them both open.

I'd first try it and see what results you get.

There are plenty of 2.5 way and 3-way home speakers that don't have separate airspace for the midbass and midrange.
 

·
Registered
Joined
·
2,298 Posts
Discussion Starter #4
Well if I disconnect my 4s as it sits right now, my 6.5s move enough air that the cones of my 4s move too. Like a passive radiator. Not to a dangerous level, but enough to figure that when it's all playing the 4s are fighting the backwave of the 6.5s as well as trying to reproduce what I'm feeding them. I expect I'll be getting a lot more movement out of the SLS cones than I'm getting out of my a/d/s/ drivers also.

My thought is that they would all run better/clearer if there was no backwave "confusion" behind the baffle. Am I mistaken?
 

·
Registered
Joined
·
2 Posts
If your main concern is keeping your 4" driver from seeing the back wave of your 6.5" driver then you really only need to enclose one of them. I'd think it'd be easier to make a smaller enclosure in your door for the 4". You just need to figure out the size and you're set.
 

·
Registered
Joined
·
2,298 Posts
Discussion Starter #7
I do plan to add some closed cell foam behind that area as well as possibly more damping, Deflex pads or Dynaxorb could be a good alternative.

Any ideas on what a good starting volume would be for a sealed a/d/s/ 4" speaker, that won't make it sound like it's in a tube?
 

·
Registered
Joined
·
5,755 Posts
If I was going to put any of them in an enclosure it'd be the mid range since it would need the smallest one. You want the MB to have as much air space as possible.
 

·
Registered
Joined
·
2,298 Posts
Discussion Starter #10
Apparently I missed half of your entry...

EDIT:

Which PX tweeter are you using? Have any experience with the 6.5 and PX in a 2 way configuration? How much more does the 4" contribute?
The 335PX and 336PX used the same tweeter, as far as I know there's really only the one version of the PX tweeter. I have these out of the billet housings so I could angle them more on-axis and still clear the door panel opening.

I LOVE the 346is mid/PX tweeter/PX crossover combination, it sounds the same to me as the full 336PX set. I'd say identical. I believe mechanically and acoustically the 346is mid and the 336PX mid are the same, just without the handbuilt billet basket of the PX mid.

I used them in that configuration in my last car off 125 watts per channel, they sounded amazing.
With the 4" also in the mix I can tell there's a lot of potential but I'm not getting what I want out of them yet because they're underpowered. I have a temporary setup running them right now with only 80 watts to each 3-way set passively crossed through Diamond Audio midbass crossovers and the PX crossovers.
I'm switching my setup to active soon since I just received my other amp today, they'll be getting 80 watts per driver next instead of 80 watts per door and I expect they'll wake up even more with the 4" in there too.

I'll be selling the 346is mids, the PX crossovers, and another set of new PX tweeters that I have, the silver PX/Concept.1 ones. Maybe as a set or maybe as individual components. The PX crossovers have been impossible to find lately, I had 8 of them and this is my last set..





 

·
Registered
Joined
·
2,735 Posts
That looks pretty nice. Sorry if I took you off track. I'm doing my first DIY with some a/d/s and was glad to see that somebody already took the plunge.

I can't say I have any profound wisdom, but based on everything I've read these guys already hit it on the head...

Seal up the mid-range, get it tuned, and tell us how it comes out? I'm excited to find out what you have to report.
 

·
Registered
Joined
·
2,298 Posts
Discussion Starter #12
I'm considering getting some XTC foam baffles for the 4" mids, and fiberglassing the outside of them to make them rigid. I don't know if it'll be the appropriate volume though because I've sealed plenty of speakers before but never tuned a sealed enclosure for a midrange..

I'd love to make an enclosure out of PVC pipe and an endcap so I can try different volumes by cutting the length down, but one side of the mid is very close to the power window motor and there's no room. I pretty much have one chance at making close to the right choice which is why I'm here asking..

Maybe an XTC foam baffle reinforced with fiberglass on the outside and loosely stuffed with polyester fiberfill?
 

·
Registered
Joined
·
2,735 Posts
I think that sounds like a pretty good start. If you're going with potential fiberglass it seems you could also "form" some type of fabric with a glue if you're having problems with tight spaces. I would think the trick would be to make sure that it's symmetrical though.
 

·
Registered
Joined
·
641 Posts
If I was going to put any of them in an enclosure it'd be the mid range since it would need the smallest one. You want the MB to have as much air space as possible.
What he said....

IMHO it's not really necessary to enclose the 4". What's most important is front/back wave separation, baffle rigidity, etc.

An enclosure of .1 - .2 cubic feet for a 4" crossed at 300 hz would probably help out improve midrange clarity and SPL. I enclosed my 6.5" woofers in about ~.4 - .5 cubic feet and it helped out in these areas.

Unfortunately it rolled off too much of the low end harmonics that I like so I ultimately had to remove the enclosure. But for your application this should not be an issue.
 
1 - 14 of 14 Posts
Top