assistance with box
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=21450
Printed Date: May 17, 2024 at 6:19 PM
Topic: assistance with box
Posted By: MAXST
Subject: assistance with box
Date Posted: November 13, 2003 at 9:08 PM
Ok..start out with what i have. two MB quart 12" subs in a sealed 1cu foot box, going to be in a 94 accord. 1: Now i heard that in that style of accord its best to point the subs up at the rear deck, is this true...if so read on, if not suggest which way. 2: i want to seal the box from the trunk..leaving the 6x9's in the trunk area, would that be wise? you see what im getting at? third and final: will the top board need bracing and will it effect the sound produce by the subs? THESE SUBS ARE LOW POWER...ONLY 150RMS. ------------- I need quality equipment, feel free to donate.
Replies:
Posted By: auex
Date Posted: November 13, 2003 at 9:20 PM
First thing you should do for question 1 is use a box that is similar to what you would be building and play with them in the trunk to actually see what sounds best to you. How would you be sealing the subs from the trunk when firing the subs toward the rear deck, taking into consideration that you are trying to isolate the subs from the 6x9? Would you be porting the enclosure through the rear deck or come up with some other way of doing this? For question 3, it is always a good idea to use a brace in an enclosure, but sometimes it is unnecessary.
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Certified Security Specialist
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Posted By: MAXST
Date Posted: November 13, 2003 at 9:29 PM
box is being built..it is what MB quart says it does best in. im going to make a hood if you will...and have it sealed up to the area around the seat. Make it look like the trunk is really smaller..wall it off. ------------- I need quality equipment, feel free to donate.
Posted By: bberman1
Date Posted: November 13, 2003 at 9:59 PM
You will probably get better sound if you have them firing into the trunk (without your hood) in a sealed enclosure. Then build a vent in the rear deck or seat so the trunk can vent into the cab. If it were me I would ditch the exterior hood idea. But if you don’t mind me asking what is you objective with the hood/external enclosure? Are you trying to push as much bass into the cabin as possible? !
Posted By: MAXST
Date Posted: November 13, 2003 at 10:05 PM
i was thinkin to put seal them off from the trunk to keep rattles out..try to..but it looks like alot of work.i think ill have them face the trunk opening. ------------- I need quality equipment, feel free to donate.
Posted By: bberman1
Date Posted: November 13, 2003 at 10:16 PM
No matter what contraption you build your going to have rattles. If you want to eliminate the rattles use Dynamat or I would suggest Brown Bread. You can do your whole trunk for about $150.00 in Brown Bread. As far as my vent suggestion I would still suggest you make a vent, it allows the trunk to breath and gives you the effect of putting down your seats.
Posted By: forbidden
Date Posted: November 13, 2003 at 10:54 PM
Some excellent suggestions, make sure you protect your 6x9's from the shock wave of the subs, you can pick up some foam or plastic baffles really cheap from your local shop, thay do an excellent job of keeping the subs from interfering with the 6x9's.
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Top Secret, I can tell you but then my wife will kill me.
Posted By: MAXST
Date Posted: November 14, 2003 at 9:30 AM
im going to use peel n seal, right close to a home depot and stuff. i dunno yet tho.... got me thinking on the vent idea. my amp is on the seat, so the arm rest vent is out. Cutting alot of metal would be necessary to do this as well, now that i think of it. forbidden: you talking about the little plastic cup things you drop in the mounting area then the speaker? Also the 6x9's are playing bass notes- trying to do what the subs are playing and its annoying. i cant firgure out how to stop it. I went thru alot of settings on my cd player...deh-p6500 pioneer, and turned up nothing. i thought since i have the rca in the sub out rca, the bass signals would only be sent to the subs. How do I stop it? ------------- I need quality equipment, feel free to donate.
Posted By: forbidden
Date Posted: November 14, 2003 at 12:00 PM
Exactly what the Dr. ordered, this little plastic or foam "hats" keep the shock wave of the subs from interfering with the motion of the 6x9's woofer. To help keep the damaging bottom end out of the 6x9's either amplify them and use the hp xover, or if you are going to continue to run the 6x9's off of deck power, you can add a passive crossover, a minimum of 6db per octave, by adding a capacitor inline on the positive speaker lead. If you look at the 6x9's tweeter, it has a small one on it (in most cases). Have a look at the passive crossover chart on this site to help you choose the appropriate value.
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Top Secret, I can tell you but then my wife will kill me.
Posted By: auex
Date Posted: November 14, 2003 at 1:35 PM
If you are trying to get the bass out of the 6x9's you could/should use a cap. IMO you will never completely get the subs away from the other speakers in the car. The pressure from the bass will still affect the speakers, even if the bass is only in the cab of the vehicle. As far as the foam "cups" go, they would be the easiest. You could also rebuild the rear deck and go with some other speakers, 6's, 8's, or stick with the 6x9's.
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Certified Security Specialist
Always check info with a digital multimeter.
I promise to be good.
Tell Darwin I sent you.
I've been sick lately, sorry I won't be on much.
Posted By: MAXST
Date Posted: November 14, 2003 at 3:19 PM
These are stock speakers, i want them to stop playing the really really low notes that the subs are playin. For stock 6x9's they are really bassy.. im running them off the HU i have. To cure myself of that i need to make a passive crossover with a cap..look on this site...ok...i take a look..looking.... OK..i have no idea what im looking at.lol If i cant get the 6x9's to tone down or it takes alot to do, just popping in some 6.5in 2 way speakers i have sitting around that can handle more power and make a box outta mdf to seal them of from the trunk..sound good? ------------- I need quality equipment, feel free to donate.
Posted By: auex
Date Posted: November 14, 2003 at 3:37 PM
Use this calc.. Just enter the resistance of the speaker and then put in what frequency you want the highpass crossover at, then hit enter. If you want low pass then use the coil suggested, if you want high pass the use the cap size suggested. For example, if you have a 4 ohm speaker and want it to play only above 200 Htz then you would need a 199 microfarad cap. ------------- Certified Security Specialist
Always check info with a digital multimeter.
I promise to be good.
Tell Darwin I sent you.
I've been sick lately, sorry I won't be on much.
Posted By: auex
Date Posted: November 14, 2003 at 3:39 PM
Ok, still can't edit. I might be wrong on the ohm part, could be speaker or resistance of the crossover circuit. Certified security specalist not audio.
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Certified Security Specialist
Always check info with a digital multimeter.
I promise to be good.
Tell Darwin I sent you.
I've been sick lately, sorry I won't be on much.
Posted By: specialblendj
Date Posted: November 14, 2003 at 8:06 PM
Yeah if you just want to cut off the bass frequencies going to the 6x9's, caps, or bass blockers/speaker savers/distortion blockers or whatever you want to call them would be a cheap way to go. There like 10 bucks a pair and you just wire them to you speaker wire, and they work like a crossover.
Posted By: forbidden
Date Posted: November 14, 2003 at 8:11 PM
What I would normally use on 6x9's to keep out some of the damaging bottom end is 200microfarad - 400microfarad non polar mylar capacitors (radio shack or electronics store or any good installers parts bins). Cut the positive speaker wire at the speaker , hook one end up to one end of the cap, hook the other end up to the other end of the cap. Problem solved except for don't turn the bass up on your cd player.
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Top Secret, I can tell you but then my wife will kill me.
Posted By: MAXST
Date Posted: November 14, 2003 at 9:22 PM
ok i got it down, thanks a bunch. Build time.... except what forbidden said..why cant i mess with the bass on the HU? ------------- I need quality equipment, feel free to donate.
Posted By: forbidden
Date Posted: November 14, 2003 at 9:27 PM
Think of the bass control on your cd as a volume control, the more you turn it up, the sooner you will cause the tiny little amp in your cd player to run out of clean power and start producing all sorts of distorted output that is faithfully reproduced by your speakers. The more you play with bass / mid / treble on a cd player, the sooner the tiny little amp will cause a clipped signal. Hope this answers your questions. ------------- Top Secret, I can tell you but then my wife will kill me.
Posted By: MAXST
Date Posted: November 14, 2003 at 9:38 PM
ahh....it did. on the p6500, it has crossovers and settings galore....one has settings for low,mid, and high....then goes to bass and treble...then HPF- which i have off, should i turn on...and to what if i should., then LPF- 80 with +3 or +4, goes to +6. theres more...but i cant remember it all... ------------- I need quality equipment, feel free to donate.
Posted By: forbidden
Date Posted: November 14, 2003 at 10:30 PM
I am not a Pioneer dealer, thus I do not know the inner workings of their cd players. I would have to do some research into whether or not the built in crossovers work with the built in amp or not. Sometimes all the settings in the world can be a real pain in the a$$. ------------- Top Secret, I can tell you but then my wife will kill me.
Posted By: MAXST
Date Posted: November 14, 2003 at 10:45 PM
oh ya, took me awhile to figure stuff out.. other than the low rca output(2 volts), its an ok hu.
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I need quality equipment, feel free to donate.
Posted By: defective
Date Posted: November 15, 2003 at 11:44 AM
could you not just adjust the frequency of the speakers with the deck? or are you targeting the 6x9s specificaly?
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Posted By: forbidden
Date Posted: November 15, 2003 at 12:11 PM
By using caps on the 6x9's it targets only the 6x9's. Again, as I am not a Pioneer dealer I am unsure of whether the cd player has the capability of frequency limitation using the built in amp / crossover. A lot of cd players that have built in crossovers only allow them to be used on a pre-amp level.
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Top Secret, I can tell you but then my wife will kill me.
Posted By: MAXST
Date Posted: November 15, 2003 at 2:49 PM
Nope...tried that. I'll do the cap thing. that'll be perfect. Thanks for the help all.. Think ill do the fronts as well. ------------- I need quality equipment, feel free to donate.
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