I built a speaker box for a pair of audiobahn 12''1200 QW powerd by audiobahn adp 2502 250w X 4 , 500 x 2 , 75 0X 1 series.the dimensions are 59.75 W 12.75 D hgt # 1 @ 16" hgt #2 @10" with a divider and two round ports 7.5 " long 4' in diamiter. (the square ft of space is 2.05892) port tuned at 40 hz.the ports are in the front of box in angled side of corner on closest to 16" side.The sound sucks compaired to the sealed box that they where in ? I tried to do as much home work as possible before making any atempt at this .The manufacture recomends 2.0 ft ported box. I took the back seat out of the truck to make room for the 12's some 10'" subs that I have, and wanted to build some thing to take up the area that was left over in the spot where the seat use to be.
I chose a ported box because i use to have one (2 15" punch powered by a punch 150 bridged ) the sound was great , so good that it has left a lasting impression .
Can you tell me what specs I should use to compliment the equipment that I have ( like square ft of space and what size the ports should be and the length of port " for both sets of speakers") the 10" s are jl audio VRC 10 W 0 series.
Replies (4)
phatphrank1970 on 07/15/2009 22:56:58
1999 chevy siberado xtended cab
swez on 07/16/2009 10:36:05
It's hard to get reliable specs on Bahn gear anymore. Some sub lines are not intended for ported use because their suspensions cannot handle it.
Also, when porting subs, we need a Subsonic filter to block the ultra deep lows that can ruin the subs and sound horrible too. In calculating the proper size chamber and port dimensions, we have to account for sub and port displacement as well. They make the chamber smaller to a degree and need to be factored in.
Also, the AWxxxx "Q" series subs, what are the voice coil ohmic ratings for this series? If you have a Mfg's link to these subs, we can review them and make some comments. (Hard to find exact model w/o a full model #)
In the meantime, protect your subs by plugging the ports and see if that does tighten up the bass to your satisfaction.
Swez
PS I have reason to believe that Audiobahn Inc., has sold out and shut their doors. (Circa 2007) If you google that name, car audio products don't show up anymore. Support from them directly is pretty much gone. (Good riddens to them as they were not all that)
FuBaR on 07/17/2009 00:15:02
SWEZ,
I can agree with your opinion on Audiobahn subs. I have made many turn into very nice and expensive Door Stops. I switched to Memphis subs, not a single issue aside from a few noise pollution tickets. What is the actual 'definition' of differences between sealed/ported/vented boxes and the drivers put in them? maybe that will help a bit
swez on 07/17/2009 05:16:23
Yep, they make great boat anchors too.
EBP or Efficiency Bandwith Product is what is needed to know to determine if a sub is usable in ported/vented boxes. If EBP is above 50, it can be ported. If below 50, sealed is a safe bet for that woofer.
The formula used is defined as Fs/Qes.
Fs is the resonant frequency of a speaker in free air. (No enclosure used)
Qes is the electrical properties, (Q) of a given driver. (Power handling and electrical impedence properties of the speaker)
Hope that helps,
Swez
I chose a ported box because i use to have one (2 15" punch powered by a punch 150 bridged ) the sound was great , so good that it has left a lasting impression .
Can you tell me what specs I should use to compliment the equipment that I have ( like square ft of space and what size the ports should be and the length of port " for both sets of speakers") the 10" s are jl audio VRC 10 W 0 series.
Replies (4)
phatphrank1970 on 07/15/2009 22:56:58
1999 chevy siberado xtended cab
swez on 07/16/2009 10:36:05
It's hard to get reliable specs on Bahn gear anymore. Some sub lines are not intended for ported use because their suspensions cannot handle it.
Also, when porting subs, we need a Subsonic filter to block the ultra deep lows that can ruin the subs and sound horrible too. In calculating the proper size chamber and port dimensions, we have to account for sub and port displacement as well. They make the chamber smaller to a degree and need to be factored in.
Also, the AWxxxx "Q" series subs, what are the voice coil ohmic ratings for this series? If you have a Mfg's link to these subs, we can review them and make some comments. (Hard to find exact model w/o a full model #)
In the meantime, protect your subs by plugging the ports and see if that does tighten up the bass to your satisfaction.
Swez
PS I have reason to believe that Audiobahn Inc., has sold out and shut their doors. (Circa 2007) If you google that name, car audio products don't show up anymore. Support from them directly is pretty much gone. (Good riddens to them as they were not all that)
FuBaR on 07/17/2009 00:15:02
SWEZ,
I can agree with your opinion on Audiobahn subs. I have made many turn into very nice and expensive Door Stops. I switched to Memphis subs, not a single issue aside from a few noise pollution tickets. What is the actual 'definition' of differences between sealed/ported/vented boxes and the drivers put in them? maybe that will help a bit
swez on 07/17/2009 05:16:23
Yep, they make great boat anchors too.
EBP or Efficiency Bandwith Product is what is needed to know to determine if a sub is usable in ported/vented boxes. If EBP is above 50, it can be ported. If below 50, sealed is a safe bet for that woofer.
The formula used is defined as Fs/Qes.
Fs is the resonant frequency of a speaker in free air. (No enclosure used)
Qes is the electrical properties, (Q) of a given driver. (Power handling and electrical impedence properties of the speaker)
Hope that helps,
Swez
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