Need help deciding what size and brand amp I need....
Mark31
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Posted on
I recently bought 2 Audiobahn 12 inch subs, along with a 900 WATT Interfire Amp. While the sound is decent inside the truch, it is almost inaudible from the outside. I was thinking of upgrading to a 1200 WATT amp, but I'm not sure if that's the proper way to solve my problem. Also, What would be a decent brand to get? Thanks.
Kicker 800.4 would work nicely for a mear $205 (got mine on ebay). Nevertheless, there are more capable amps, no doubt, but for the price Kicker works well.
ummm ideally, you don't WANT to hear anything outside of teh truck. anything you hear outside is wasted energy that should e otherwise contained inside the vehicle to make it louder INSIDE the truck sound is energy. people don't seem to get this.
and by the way, nobody else really WANTS to hear your system at a stoplight anyway.
If you are the sort who finds pleasure in annoying other people with your music, don't be surprised when you encounter someone like me, who finds even more pleasure in following you to your destination at a leisurely distance, and slashing your tires while you're in Wal-Mart buying your flintstones vitamins.
Mark31
Unregistered guest
Posted on
Thanx for the advice. I'll take other drivers into consideration. I was asking a friend today that knows a little about stereo's, and he said to not necessarily look for big #'s when it comes to amps. He was saying that there was a big difference between a 1200 WATT max and a 1200 WATT RMS. Should I take it into consideration? This could be the reason my lights dim everytime my subs hit hard. Any advice would be appreciated.
he's very much on the money there. good friend to listen to. RMS is a "continuous" maximum output. "peak" or "max" ratings are inflated, misleading ratings used by lesser companies to make a product look more impressive. the peak rating is what a speaker can handle, or an amp can put out, for a brief moment, in a "burp" or split second of spiked output. peak ratings can't be sustained, and are usually about four times that of the RMS rating of the product. Now, knowing that, also keep in mind that even if an amp is rated for 1200wRMS, such as, say, a JBL BP1200.1 or Kicker KX1200.1, this doesn't mean the amp is always putting out 1200 watts. at max volume, the amp will put out an average sustained wattage of ~1200 watts. remember that volume, in dB (decibels) is a log scale, and not linear. every +10dB is double the audible volume, and to attain twice the audible volume, the amp has to put out ten times the power. in other words, if you're listening at a moderate level, you may be only using about 50 watts of RMS power for the subs. if you turn up the volume to what appears to be twice as loud, you're now maintaining an RMS power from the amp of about 500 watts. so, if ya don't crank the amp to full output, you may only be using a fraction of that 1200 watts.
ok, now with that out of the way, if your lights are dimming, you need a larger alternator. a 1200 watt amp (RMS) amp (class D) will draw around 114A continuously, at full output. most stock alternators only put out about 70-100A total, and the car uses most of that for its own electrical needs.
you may want to dynamat the truck too. it'll make it even more muffled outside of the vehicle, but it'll kill metal vibration inside, and make it sound better where it counts.. to you, the driver.
Mark31
Unregistered guest
Posted on
Thanx a BUNCH, that makes everything a lot clearer. I'll try and find out if the alternator's just a regular stock one. The guy I bought the truck from had a system, but If the lights are dimming this easily, I very much doubt it's anything but stock. Going back to the Amp, The way I'm thinking, unless I'm going to be pushing my system to the max 24-7, and using all 1200 watts, I might as well just save a little money and go with a slightly smaller amp that can still give me great quality. Got any suggestions on a brand of amp? I was thinking possibly a JBL, or someone suggested Orion. I know my Audiobahn's are probably mostly just about looks and not quality, I guess that's why they're so popular with all my HS friends. I'm stuck with them tho. I was wondering however, is the same true fore the Audionbahn amps? Thanx.
Orion has very good amps. I own several myself. expensive though. look at Kicker, JBL, Avionixx, and MTX for amps, in the 600wRMS range, @ 2 ohms perhaps
remember though,if you underpower the subs, you'll decrease the bass, and may try to compensate by turning up the volume, which, in the end, uses just as much power to attain the same volume levels anyway. power + excursion + surface area + box type pretty much determines your SPL.
anyway, a 200A alternator is $180-300 on average.. depends on the vehicle. All in all, it's not that big of an investment for the good it'll do the system. The power source for the system is a vital link in the chain for any good setup.
I'm looking around at a 2001 Intrepid R/T now myself, and the first thing I'll do if I buy one, is pull it into the garage, drop a 200A alternator in it, a battery isolator, then gut it from dash to trunk, dynamat the hell out of it, and run all the cabling for two more batteries in the trunk, and 1/0 AWG power cable. Then, I'll re-assemble the car, and start looking at the audio system itself. heheh when it's done though I figure I'll have about seven grand in the hardware, and who knows how many hours in labor but it should do well at shows.
Mark31
Unregistered guest
Posted on
Sounds great. Thanks again for all the help. I'll write again if I have anymore questions.
Mark31
Unregistered guest
Posted on
Hey, I've been looking around, and think I found a couple pretty decent amps, but I don't want to buy one if I'm not 100% sure it's what I need. The one's i was most thinking about was either a KX1200.1 or KX600.1. I have the specifications on both if you need them
Is the KX1200.1 RATED FOR 1200watts RMS? i'm lookin closer at it on e-bay and it only says 300. Is there anything bigger than that?
Mark31
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Performance The RMS Power Output 300 x 1 The Frequency Response - 20-200 Hz The THD at Rated RMS Power - 1.5% The Signal to Noise Ratio - 95 dB The Input Voltage -13.8v The - Peak Power Output - 1200 x 1 The Power at 2 Ohms - 600 x 1 The Minimum Impedance Unbridged - 1 Features What Amplifier Class?D The Low Pass Crossover Frequency - 50-200Hz The Low Pass Slope - 12dB The Bass Boost - 0-18dB The Bass Boost Frequency -40Hz Is it Fan Cooled?Yes What Fuse Rating? 150 x 1 Does it have Speaker Level Inputs? Yes Does it have Preamp Outputs? 1 pair What color LED Power Indicator? Green Height 2-9/16" The Width - 22-11/16" The Length - 10-1/8"
Great. I went ahead and got the amp, but I was wondering what I should do with my Interfire amp. One my my friends uses an amp for his highs, and another for his lows. Could i just hook up my extra amp like that? Also, i bought a larger alternator, and a second battery. As it turned out,the battery cables on my first were fried. 2 should work great tho.
