posted
I recently blew a pair of comp JBL GT subs circa 1988. got almost 20 years from them, never paid attention to sub characteristics as much throughout the years, but now I am curious.
I was feeding them for 5 years with an equally old Alphasonik, forgot the model but it was only 125watts per channel x2, and that was split between 4 VC's
Bought a lightning audio S.600 4 channel.. Had 225 Watt @ 2ohms X 2 which worked well on them JBL's but time and dry rot on the surround got the best of them....so enough of that. I bought some cheap 12" Kicker CVR's dual 4ohm.
Not up to the standards of many on this board i'm sure, but it suits me for the time being.
Their loaded in a custom sealed box I built 1.65CFM per side. under the back seat of a 2000 Dodge Ram quad cab. Will post pics sometime, was quite fun.
First the CVR's definately sound louder than my JBL's even though the efficiency is lower.
Now I am wondering If am driving them too hard.. They handle 450Watts rms I am giving them only 225 watts each...
The gain on the amp is 75 percent. Xover at about 80 hz.
Question is,,,
1. The cone moves a lot more than the 12.65mm or 1" + on the deepest notes,,, it sounds clean, no clipping of the amp, no bottom out of the magnet, nothing that sounds out of place. In fact, it sounds louder and cleaner with those low notes.
But this excessive travel has me worried if it isn't good for the sub...
2. I'm only feeding them half their rated power. If I opt for an amp that is 500 X 2 is this really going to help me make it louder, if I am already beyond the XMAX rated?
Can it play louder with less cone travel? I thought moving air was the key.
Thanks,
Added some pics of my one of a kind Dodge Ram Under seat box.
Combination of Fiberglass and 3/4MDF. Poured inside the truck to form the floor contour. The neighbors loved the smell. 1.65CF per side, which is not easily done without raising the rear seat. Which I accomplished with 2" channel welded and placed as seat lifters. Plenty of room for my kids to fit back there. My amps are mounted on the back wall, but I can't take a pic until I clean up a couple wires. Don't want it too look half assed.
posted
I have a Pioneer DEH P7000R pretty old too...
I have it wired to my JBL dome tweets.
The Alphasonik pma50x2 to the rear 5 1/4" Pioneers and the Lightning Audio fronts 90 X 2 to the Sony XS697's (another 15 yo speaker)
All this rescued and replanted from a 88 Firebird I had them in,,,
Just couldn't part with the stuff. The only thing I parted with was the very first 10" bazooka tube to ever come out...as well as a Alphasonik 60 watt mono amp that was driving it.. That was crap, i'll admit that.
I can turn the gain down, but now I lose volume.
What I was wondering is, can I actually feed them more power, like 450 watts to make them play even louder? but without the cone travel being so drastic...
Perhaps I am asking to much of this setup. Even though it is half power.
I do remember my old JBL setup and this amp doing something like 136DB with a cheap meter I got at Rat Shack. Nothing technical, but had something to go buy when I was making adjustments. too bad I broke it, and can't see what I got now.
This new setup and CVR's make my eardrums rattle harder, and mirrors shake way more...
posted
Subs are made to move like that. Especially when you use sealed enclosures. I wouldn mind about it to much. Your best choice would be to buy a 800w rms @ 1ohm amp. That will be able to control the subs alot better than what you have now.
For example, I had 1 12" L7 dual 2 ohm kicker sub hooked up with 1 500x2 rockford fosgate amp. and when the sub hit the low notes (say 35hz) the cone apeared to want to come apart from the basket. Now when I purchased a 600w rms @ 1 ohm digital designs ss1 amp The story changed, and when the sub hit 35hz it sounded way louder and with less excursion. The End.
Posts: 203 | From: Puerto Rico | Registered: Jan 2006
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Your RF amp, that was 500watts on each coil at 2ohms?
And you went with less watts 600@1ohm into the same speaker? 300per coil? and it sounded better.
Just want to make sure I understood that right.
I was wondering how it could play louder without the extra excursion. I was looking at a 600@1ohm, but if these subs can take 900 combined, I will parralell them and throw a nice 1ohm amp at them...
-------------------- World Record-Loudest SPL in my driveway Team Powermaster/XS-Power Hifonics Amps, Kicker subs-The way it should be....all were Stolen from me...boo hoo Zensky....World Domination at It's Finest www.zensky.com Posts: 3750 | From: Columbus, OH - formerly FL | Registered: Oct 2003
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quote:Originally posted by sabydaddy: Subs are made to move like that. Especially when you use sealed enclosures. I wouldn mind about it to much. Your best choice would be to buy a 800w rms @ 1ohm amp. That will be able to control the subs alot better than what you have now.
For example, I had 1 12" L7 dual 2 ohm kicker sub hooked up with 1 500x2 rockford fosgate amp. and when the sub hit the low notes (say 35hz) the cone apeared to want to come apart from the basket. Now when I purchased a 600w rms @ 1 ohm digital designs ss1 amp The story changed, and when the sub hit 35hz it sounded way louder and with less excursion. The End.
nice story bud.. and careful with the gain buddy..still tough though without clips.. Posts: 65 | From: manila | Registered: Jan 2008
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