Right, my friend is being pathetic and wants to keep his rear seats, so for now we have this ammount of space to play with:
Height 30" (762mm)
Width 43" (1092mm) the width at the top is the same as between the wheel arches
Depth 43" (1092mm)
Once I have finished beating the idea that loosing the back seats is a good thing, I think we should have about 20" more depth to play with.
For subs, the amp we have is happy doing 2 X 1000Watts RMS into 2Ohm, it will give about 20% more than this with the alternator running as its unregulated. because of this I'm looking at either a single Volt R3853 which is 4 ohm so bridge the amp and give it 2000w (I'm pretty confident they can take this power as a friend of mine runs this kind of power to RV3823s in his PA rig) Or use the RV3823 which is only available as an 8Ohm driver, but we could parallel 2 of them, is there room to do this, this would give more cone area and better powerhandling?
R3853
Nominal Diameter 381 mm
Power Capacity 300 watts
Sensitivity 93 dB/watt/m
Frequency Range 30-500 Hz
Impedance 4/8/16 ohms
Bl Factor 19 N/A
Voice Coil Diameter 75 mm
Voice Coil Material Copper
Maximum Excursion 28 mm (before damage)
Fs 32 Hz
Re 7 ohms
Qa 3.25
Qe 0.44
Qt 0.39
Vas 172 litres
Xmax 5.5 mm
Sd 734 cm2
Vd 600 cm3
Le 1.2 mH
R3823
Nominal Diameter 380 mm
Power Capacity 500 watts
Sensitivity 96 dB/watt/m
Frequency Range 30-500 Hz
Impedance 8/16 ohms
Bl Factor 19 N/A
Voice Coil Diameter 75 mm
Voice Coil Material Copper
Maximum Excursion 28 mm (before damage)
Fs 39 Hz
Re 5.4 ohms
Qa 3.25
Qe 0.35
Qt 0.32
Vas 133 litres
Xmax 4.5 mm
Sd 755 cm2
Vd 340 cm3
Le 0.9 mH
Height 30" (762mm)
Width 43" (1092mm) the width at the top is the same as between the wheel arches
Depth 43" (1092mm)
Once I have finished beating the idea that loosing the back seats is a good thing, I think we should have about 20" more depth to play with.
For subs, the amp we have is happy doing 2 X 1000Watts RMS into 2Ohm, it will give about 20% more than this with the alternator running as its unregulated. because of this I'm looking at either a single Volt R3853 which is 4 ohm so bridge the amp and give it 2000w (I'm pretty confident they can take this power as a friend of mine runs this kind of power to RV3823s in his PA rig) Or use the RV3823 which is only available as an 8Ohm driver, but we could parallel 2 of them, is there room to do this, this would give more cone area and better powerhandling?
R3853
Nominal Diameter 381 mm
Power Capacity 300 watts
Sensitivity 93 dB/watt/m
Frequency Range 30-500 Hz
Impedance 4/8/16 ohms
Bl Factor 19 N/A
Voice Coil Diameter 75 mm
Voice Coil Material Copper
Maximum Excursion 28 mm (before damage)
Fs 32 Hz
Re 7 ohms
Qa 3.25
Qe 0.44
Qt 0.39
Vas 172 litres
Xmax 5.5 mm
Sd 734 cm2
Vd 600 cm3
Le 1.2 mH
R3823
Nominal Diameter 380 mm
Power Capacity 500 watts
Sensitivity 96 dB/watt/m
Frequency Range 30-500 Hz
Impedance 8/16 ohms
Bl Factor 19 N/A
Voice Coil Diameter 75 mm
Voice Coil Material Copper
Maximum Excursion 28 mm (before damage)
Fs 39 Hz
Re 5.4 ohms
Qa 3.25
Qe 0.35
Qt 0.32
Vas 133 litres
Xmax 4.5 mm
Sd 755 cm2
Vd 340 cm3
Le 0.9 mH
Two 15" drivers on the horn?Very hard to fit+large rear chambers occur.
Consider two routes
-Scoop
-front loaded,rear sealed horn
with that size a horn is certainly possible.Its just a question of cutoff and sensitivity vs cutoff.
Xmax is still listed quite low...it wont matter for music at sane levels.
Consider two routes
-Scoop
-front loaded,rear sealed horn
with that size a horn is certainly possible.Its just a question of cutoff and sensitivity vs cutoff.
Xmax is still listed quite low...it wont matter for music at sane levels.
CBFryman, postage would be a bitch from the UK 
Mike.e
Right please explain in VERY BASIC TERMS what I can do with a single 15" as it looks like twin 15s will be too much. The Xmax is low but they are a lot more linear that the figures suggest, they can be run to 20-25mm excursion for extended periods, no problem and still sound very good.
Front loaded rear sealed, sounds to me like a basic sealed box with the sub firing into a horn.
Scoop, your've lost me but I'm thinking something like the PA Cabs which have a folded horn at the top and the mouth looks like a bucket scoop.
You say its a matter of Cutoff (as low as realistically possible) and sensetivity Vs Cutoff (how does this work then).
Mike.e
Right please explain in VERY BASIC TERMS what I can do with a single 15" as it looks like twin 15s will be too much. The Xmax is low but they are a lot more linear that the figures suggest, they can be run to 20-25mm excursion for extended periods, no problem and still sound very good.
Front loaded rear sealed, sounds to me like a basic sealed box with the sub firing into a horn.
Scoop, your've lost me but I'm thinking something like the PA Cabs which have a folded horn at the top and the mouth looks like a bucket scoop.
You say its a matter of Cutoff (as low as realistically possible) and sensetivity Vs Cutoff (how does this work then).
Nope the amp is a stereo AB, rated at 2X1000W RMS into 2Ohm, that is about what it puts out from an 10.5V supply, at 12.5V we measured 1248Watts RMS per channel, and it keeps going up almost linearly to 15.5V if you can keep the voltage up, the amp is barely 60% efficient so if you do the math you get an idea of the current draw and why keeping the voltage up is such a mission. it is rated as stable at 4Ohms bridged but will run at 2ohm bridged if you can keep it cool enough and if you can keep the voltage up near 14V then it will do 3kW bridged
It is a beast of an amp: US Amps 2000X which is the predecessor to the AX2000. www.usamps.com.
I've given up on a big enough alternator, just running with a couple of 110Ah batteries about 6" from the amp.
It is a beast of an amp: US Amps 2000X which is the predecessor to the AX2000. www.usamps.com.
I've given up on a big enough alternator, just running with a couple of 110Ah batteries about 6" from the amp.
Puggie: it takes alot of detailed writing!
You MUST read these links first
http://www.diyaudio.com/wiki/index.php?page=basshorn
http://www.volvotreter.de/ ->Downloads -> Dinsdale horn files/edgar horn files
A scoop is a horn where only one side of the cone is loaded,the rear is un enclosed. Theirs nothing too wrong about this apart from asymmetrical loading,causing 2nd harmonic distortion. Most commercial basshorns dont do this. However,if people are used to hearing reggae through scoops with this distortion,people will like the sound:d
Okay so now post the t/s specs of the woofer youl use.
What was the dimensions[max] again?
State what sort of music etc
And what is your aim
Then I can help with modeling,and CADing up the horn.
Cheers
You MUST read these links first
http://www.diyaudio.com/wiki/index.php?page=basshorn
http://www.volvotreter.de/ ->Downloads -> Dinsdale horn files/edgar horn files
A scoop is a horn where only one side of the cone is loaded,the rear is un enclosed. Theirs nothing too wrong about this apart from asymmetrical loading,causing 2nd harmonic distortion. Most commercial basshorns dont do this. However,if people are used to hearing reggae through scoops with this distortion,people will like the sound:d
Okay so now post the t/s specs of the woofer youl use.
What was the dimensions[max] again?
State what sort of music etc
And what is your aim
Then I can help with modeling,and CADing up the horn.
Cheers
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