Topic: School me on car audio stuff

[KDXSR5]

yes you can do that if you have two sets of RCA connections on your deck

You just confused me. I thought I could take the 4 sets of speaker wires off of my deck and run them to the HI INPUT on an amp and have that run the 4 speakers. Then run RCA from the back of my head unit to a different amp to power a sub. But you say I must have two sets of RCA to do that... which I do not have, I only have one set. I am lost again.

[Duffil]

You just confused me. I thought I could take the 4 sets of speaker wires off of my deck and run them to the HI INPUT on an amp and have that run the 4 speakers. Then run RCA from the back of my head unit to a different amp to power a sub. But you say I must have two sets of RCA to do that... which I do not have, I only have one set. I am lost again.

what he means is with a 4channel amp, you could run from dual RCA pre-outs.

I've been basing my comments knowing you have a single pre-out.

[pumkin toy]

yes that looks correct!  but i thought that the 4 channel amp would also have to be connected to a set of RCA's coming from your head unit, just like the amp running the sub. but i could be wrong.  come to think about it i want to know the answer to that question for sure! lol  sorry i'm not trying to confuse you, i just thought that each amp HAS to have a set of RCA's

[Duffil]

yes that looks correct!  but i thought that the 4 channel amp would also have to be connected to a set of RCA's coming from your head unit, just like the amp running the sub. but i could be wrong.  come to think about it i want to know the answer to that question for sure! lol  sorry i'm not trying to confuse you, i just thought that each amp HAS to have a set of RCA's

no you are not required to run RCAs.

[KDXSR5 [OP]]

Ok cool. Now that I have how it works figured out, how do I go about selecting an amp for my 4 speaker system?

I know I need:
4 channel
HI INPUT (this is assuming not all amps have this option)

But what else do I need as far as watts and such are concerned? Again, I am retarded on this subject (amongst others) so I need lots of help.

[pumkin toy]

no you are not required to run RCAs.

awesome!  thats good to know, because i have a mono block amp running the sub in my S2000 and i also have a four channel i would like to hook up to the regular speakers.

[86bobbedtoy]

Ok cool. Now that I have how it works figured out, how do I go about selecting an amp for my 4 speaker system?

I know I need:
4 channel
HI INPUT (this is assuming not all amps have this option)

But what else do I need as far as watts and such are concerned? Again, I am retarded on this subject (amongst others) so I need lots of help.

yeah not all amps have this option
you can also get a line level to RCA adapter- 20$
I highly recomend a Rockford amp there cheap on ebay and put out awesome amounts of power
my t3002 says 965 on the birth sheet bridged @1 ohm
378x2 at 2 ohms

[Duffil]

how much do you want? 400 setup properly will pound like hell in a small cab. Of course, you don't have to turn it up that far.  I say if you are looking at a 4channel setup, 300 or more and you should be able to tune it to your needs.  Where's that 86bobbedtoy guy he's better than I am with this stuff I think.

edit: there he is!

[KDXSR5 [OP]]

So how does this one look? I am just using crutchfield to search because I am somewhat familiar with their website.

My deck (Blaupunkt BPV660 http://www.crutchfield.com/p_023BPV660/Blaupunkt-BPV660.html?tp=5684 ) has 27 watts RMS x 4 so I figured that this one with 75 watts RMS x 4 would work much better.


http://www.crutchfield.com/p_023THA475P/Blaupunkt-THA475PnP.html?showAll=Y&tp=115

[Duffil]

not bad but you'll be paying more for it than it's worth IMO.

another thing to consider is how much power your speakers can handle. That amp pushes 85W RMS max to 4 outputs...can your mids/highs handle it?  if you drive your speakers too hard they will distort.

[KDXSR5 [OP]]

not bad but you'll be paying more for it than it's worth IMO.

another thing to consider is how much power your speakers can handle. That amp pushes 85W RMS max to 4 outputs...can your mids/highs handle it?  if you drive your speakers too hard they will distort.

I wont be buying through crutchfield, they are expensive.

How do I figure out what my speakers can handle?

[KDXSR5 [OP]]

JBL 4 incher specs (dash)

Power Handling, RMS 50 Watts
Power Handling, Peak 150 Watts
Sensitivity 91dB 
Frequency Response (±3dB) 75Hz - 23kHz
Impedance 2 Ohms



Pioneer 6x9s in boxes specs

Specifications
Watts MAX. Music Power 440 Watts
Watts Nominal Power Handling (RMS) 80 Watts
Frequency Response 25Hz ~ 33kHz
Sensitivity (1W/1m) 93dB
Ohm Rating 4 ohm


What can be told by these in respect to the power I should be looking for in an amp?


And what is up with the two different ohm readings? 2 for the small ones and 4 for the big ones?

[86bobbedtoy]

well the 2 ohmers bridged would be a 1 ohm load not all amps can handle this for long periods.
also when you bridge an amp you kill the sound quality
never bridge mids or highs
I would say a 2-400 watt amp remember the brand has alot to do with it.
and never buy anything from Crutchfield- ever,
they are over priced and dont like to honor there waranties.
I used to really like the sound quality of the pioneer amps.
they made a 300 watt for a while but not sure if they still do.

[KDXSR5 [OP]]

well the 2 ohmers bridged would be a 1 ohm load not all amps can handle this for long periods.
also when you bridge an amp you kill the sound quality
never bridge mids or highs
I would say a 2-400 watt amp remember the brand has alot to do with it.
and never buy anything from Crutchfield- ever,
they are over priced and dont like to honor there waranties.
I used to really like the sound quality of the pioneer amps.
they made a 300 watt for a while but not sure if they still do.

So... When looking at the 4 channel amps they list them as whatever watts RMS x 4. Should I be adding up those RMS reedings to get the 300 watt or whatever big watt number you are referring to?

[Duffil]

yep. same as a deck. Pioneer 40W is 10wx4.

[KDXSR5 [OP]]

ok cool, got that figured out.Well actually does the added up watts number go off of the RMS or Peak?  Also is there going to be a problem running a 4 channel amp for 4 speakers when 2 of them are 2 ohm and 2 of them are 4 ohm?

[Duffil]

peak usually. try to ake it seem bigger/better. only brand I know rates off of RMS is Eclipse.

[KDXSR5 [OP]]

Ok cool. What about running two 2 ohm and two 4 ohm? Problem or not?

[Duffil]

depending on wiring man,and what your amp can handle. get an amps, then wire the speakers to the lowest the amp can handle.

[KDXSR5 [OP]]

depending on wiring man,and what your amp can handle. get an amps, then wire the speakers to the lowest the amp can handle.

Now I am lost again lol.

[blackdiamond]

awesome!  thats good to know, because i have a mono block amp running the sub in my S2000 and i also have a four channel i would like to hook up to the regular speakers.

You can always run an RCA "Y" cables to split the low level into multiple amps.  You don't have to worry about ohm load issues with low level inputs.

 

[blackdiamond]

JBL 4 incher specs (dash)

Power Handling, RMS 50 Watts
Power Handling, Peak 150 Watts
Sensitivity 91dB 
Frequency Response (±3dB) 75Hz - 23kHz
Impedance 2 Ohms



Pioneer 6x9s in boxes specs

Specifications
Watts MAX. Music Power 440 Watts
Watts Nominal Power Handling (RMS) 80 Watts
Frequency Response 25Hz ~ 33kHz
Sensitivity (1W/1m) 93dB
Ohm Rating 4 ohm


What can be told by these in respect to the power I should be looking for in an amp?


And what is up with the two different ohm readings? 2 for the small ones and 4 for the big ones?

Have you ever heard the term "KISS" for "keep it simple stupid?"

If you're planning to run your four main speakers from an amp, the power of your head unit means nothing since the power isn't directly driving the speakers.  As long as you don't have an amp (or head unit if hooked up directly) that has significantly more power available than your speakers can handle you won't have to worry about it at non painful listening volumes.

Concert volume is somewhere around 96 dB and your speakers will produce 91 & 92 dB sounds with 1 watt input, this is what the sensitivity rating means.  If you had a 4 channel amp for the four main speakers that was rated in the 50 to 100 watts per channel (200 to 400 watts total) you'll NEVER have a problem.  Quality is more important than power.

Legacy makes amps that have high ratings but yield crappy sound.  I've owned a 20 watt AIWA shelf stereo that sounded WAY better than a similar 100 watt Pioneer.

[86bobbedtoy]

peak usually. try to ake it seem bigger/better. only brand I know rates off of RMS is Eclipse.

and fosgate

[Duffil]

yeah actually you do. you can't run a 2 ohm speaker system with an amp that is only 4 ohm stable, regardless of running hi or low level inputs.

[blackdiamond]

depending on wiring man,and what your amp can handle. get an amps, then wire the speakers to the lowest the amp can handle.

With a 4 channel amp he should be looking at one for one meaning each speaker has it's own channel.

He could split the input (from the head unit to the amp) and I doubt it would make any difference since the amp, and not the head unit, would be loaded by the speakers.

[KDXSR5 [OP]]

Have you ever heard the term "KISS" for "keep it simple stupid?"

If you're planning to run your four main speakers from an amp, the power of your head unit means nothing since the power isn't directly driving the speakers.  As long as you don't have an amp (or head unit if hooked up directly) that has significantly more power available than your speakers can handle you won't have to worry about it at non painful listening volumes.

Concert volume is somewhere around 96 dB and your speakers will produce 91 & 92 dB sounds with 1 watt input, this is what the sensitivity rating means.  If you had a 4 channel amp for the four main speakers that was rated in the 50 to 100 watts per channel (200 to 400 watts total) you'll NEVER have a problem.  Quality is more important than power.

Legacy makes amps that have high ratings but yield crappy sound.  I've owned a 20 watt AIWA shelf stereo that sounded WAY better than a similar 100 watt Pioneer.

I know the head units power does not matter if running an amp to the 4 speakers because the power is coming from the amp, not the head unit. But I don't want to over power my speakers. Which is why I listed the specs for both of the speakers I have. So you are saying just go with any good quality brand 4 channel amp with anywhere from 50w RMS x 4 on up? And just not worry about over powering them?

[blackdiamond]

yeah actually you do. you can't run a 2 ohm speaker system with an amp that is only 4 ohm stable, regardless of running hi or low level inputs.

You are correct that you can't run 2 ohm speakers on an amp that is only 4 ohm stable, BUT the low level input into the amp makes no difference.  Low level imputs have nothing to do with the load on the amp.

A lower ohm loading will simply produce more heat in the amp and it's the heat that damages the amp.  They are rated so that the cooling is adequate to run at a normal operating temp.  At low volumes you won't have a problem.  The problems come with the power required to push bass.

One of my best friends in an electrical engineer that enjoys both car and home audio so I've picked his brain on this stuff over the years.

[KDXSR5 [OP]]

So if I get a 4 channel amp that is stable for 2 ohm loads I should be ok.

[blackdiamond]

I know the head units power does not matter if running an amp to the 4 speakers because the power is coming from the amp, not the head unit. But I don't want to over power my speakers. Which is why I listed the specs for both of the speakers I have. So you are saying just go with any good quality brand 4 channel amp with anywhere from 50w RMS x 4 on up? And just not worry about over powering them?

Yes - Just look for a quality brand (Kenwood makes quality amps) with a reasonable rating and don't worry about it.

[Duffil]

I never said the input makes a difference. go ahead and push 1/2 ohm through a 4ohm stable amp at 500Watts. just do it. I am done contributing to the thread now that the "smart" people have joined in.