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stieater
06-05-2005, 02:03 AM
I'm fairly new to the whole high-end audio world. so ive got a few questions. looking at component speakers and i was told that the amp had to have a higher rms output than the speakers required. (example; speaker rms power range : 60W. amp RMS power : 100W X 4) right? now does that 100w X 4 mean that it will put out 100w for each speaker?

Beat_Dominator
06-05-2005, 02:06 AM
100 watt would go to each channel.... Front Left, Front Right, Rear Left, Rear Right.

But if you go high-end on comps. you'll want to be able to go over the manufacturers specs because it would give you room to spare in teh power dept.

desi_daru
06-05-2005, 02:13 AM
u dont HAVE to send them more power, but jus like the above post said it gives you head room, all u gotta do then is jus set the gain accordingly and you should b fine

jsloan10
06-05-2005, 02:14 AM
Rather than explain I found an FAQ that saves me the effort of typing-


5.21 What's worse for a speaker, too much or too little power? [IDB]
================================================== ====================

Problems occur (in everyday operation) when distortion is fed to a
speaker. This occurs MUCH more often when you are dealing with an
underpowered system - typically the owner will turn up the volume too
much or set the amplifier gains too high to try and get more volume
from the system. These introduce distortion to the signal - this will
destroy *any* speaker. ((see Section 5.22).)

When a speaker is overpowered, however, it is not nearly as common to
have these kind of problems, so speakers aren't blown as much. Of
course, it is certainly possible to destroy a speaker (thermally) by
overpowering it, but you'll have a pretty hard time doing this on your
own, especially with standard car audio amplifiers.


5.22 Why is distortion harmful to my speakers? [RK]
================================================== ===

Distortion is hard on speakers for two reasons.

Reason 1: Distortion causes the power spectrum to shift upwards in
frequency. A bass note, when distorted, will have lots of high
frequency energy. This will cause mid-ranges and tweeters to fry, if
the amplifier is operating full range. It doesn't harm woofers,
necessarily.

Reason 2: Distortion causes the average power to be much higher.
Typically, a music signal that never clips has an average power level of
1/4 the peak power level for even the most compressed speed metal or
pop. More dynamic music will be 1/8 the peak level or less on average.
When you clip the amp hard, the average output moves up to the
full-rated output of the amp or more. The peak to average ratio can be
less than 2 to 1, with the peaks being at double the rated power of the
amp, and the average being at the rated power of the amp or higher.

Thermally, the speaker can handle the average power being 1/4 the rated
power of the amp (little to no clipping), but it will have a much harder
time with the average power being the amp's rated power or more (massive
clipping). As you might expect, this is pretty hard on the amp, too.

For transients, most speakers can handle a ton of power. But for long
term signals, the power handling is much less.

stieater
06-05-2005, 02:20 AM
not looking to spend much money...just something decent would this amp work for these ok for these sets of speakers?
http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=13124

http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=14400
http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=14403

Beat_Dominator
06-05-2005, 02:22 AM
That amp would only give them 50w.

jsloan10
06-05-2005, 02:26 AM
75 x4 rms Kenwood 8452
link-
http://www1.bottomdollar.com/p__Kenwood_Kenwood_KAC_8452_4_Channel_Amplifier,__ 7485886//

Beat_Dominator
06-05-2005, 02:27 AM
:laugh: you and your Kenwood.

stieater
06-05-2005, 02:38 AM
so id need an amp thats rms power range is higher than that of the speakers?

Beat_Dominator
06-05-2005, 02:39 AM
Those speakers said like 120w max. So an amp from 80-150 would work.

stieater
06-05-2005, 02:42 AM
ok so make sure the amp is higher than the rmp power range and peak power. anything else? ohms?

stieater
06-05-2005, 02:43 AM
*rms power range

Beat_Dominator
06-05-2005, 02:43 AM
Those are 4ohm speakers, so you need to just look at the 4ohm power ratings.

stieater
06-05-2005, 02:52 AM
does this work? http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=13117

Beat_Dominator
06-05-2005, 02:55 AM
Yeah, but for that price you can do better used in our classified section.

stieater
06-05-2005, 03:06 AM
ok cool thanks. one other question. this is about amp/sub hookup. ive got a mono amp running two 12" subs. does running the subs in series mean that the pos/neg from the amp connect to one sub and then the pos/neg from that sub is connected to the pos/neg of the other? or is that parrellel? i think the other kind is running a pos/neg wire from the amp to each sub. also, which produces more bass?

Beat_Dominator
06-05-2005, 03:10 AM
like this? http://www.rockfordfosgate.com/rftech/wiringwizard.asp?WoofQty=2+woofers&WoofImp=Single+Voice+Coil+-+4+ohms&image.x=15&image.y=11

stieater
06-05-2005, 03:16 AM
the first one is one of the wireing diagrams i was talking about. never seen the second but instead of having the neg from sub1 go to the pos of sub2, the pos/neg from sub1 would go to the pos/neg from sub2. also the pos/neg from the amp would only go to one sub

Beat_Dominator
06-05-2005, 03:21 AM
What sub model do you have?

stieater
06-05-2005, 03:24 AM
theyre back at my sisters in the states and all i know is that theyre 12" eclipse aluminums. 500w rms each and the rockford fosgate amp is 1000w rms. my buddy i got them from said that either wireing set-up will work but i cant get a hold of him to ask him which hits harder.

Beat_Dominator
06-05-2005, 03:26 AM
Well you need to know the ohm rating of the voice coils, and if it is Dual or single voice coil. That determines what final Ohm load that you can wire them to for the amp.

If you wire them wrong you will either give the subs too little power, or risk damage to the amp.

stieater
06-05-2005, 03:30 AM
ok thanks

Beat_Dominator
06-05-2005, 03:30 AM
No prob. I'm gonna sleep now :laugh: