HaveBlue

Hi All-
For all you stereo gurus out there:

Can you use two amps to power 6 speakers? In other words, I have a friend who is wiiling to sell me his two Sony 2-ch amps. I will be powering 4 front speakers (2 stock mid-range with tweeters, 2 new mid-range with tweeters in kickpanels) and 2 rear speakers (Sony). Can I power the 4 front with a 2-ch and the 2 rear with a 2-ch?

Thank you!

tomus1000

Sure you can. You just need to make sure that your head unit has 2 outputs (front and rear). If not, you have to split the one RCA output to go to both amps. This will work but you will have no "fade" control (kind of like "balance", just front to rear).

This is all assuming that you have an aftermarket radio in the vehicle. If you do not, get one before buying the amps. With a factory radio you are forced to use a HIGH/LOW level converter. The quality of this conversion for car stereo aplication is poor at best.

The only problem with your 6 speaker scenario is that the amp that is running the 4 speakers is going to drown the one that is running only 2. When you run 4 speakers off of a 2 channel amp you reduce the resistance load, thereby doubling the power output from the amp. If they are 100 watt amps, one will be putting out 100 watts, and the other will be putting out 200 watts. Ther rear speakers will play at half the volume of the fronts.

Well, this info should help you or throughly confuse you. In either case, I'm happy to help.

Noel

Cebby

You need to know if the amps can drive a 2 Ohm load. Likely your existing speakers and new speakers are 4 Ohm. If you wire these in parallel, your amp will see a 2 Ohm load. If it isn't rated to drive 2 Ohm it will overheat and shutdown. If it doesn't have a good protection circuit bult into it, it will cook the amp. If it can drive a 2 Ohm load, it will typically develop twice the power than in 4 Ohm - you might run into a power handling issue with the stockers. An alternative is to wire the front speakers in series. If all the speakers are 4 Ohm, your amp will see an 8 Ohm load. This isn't good, because the amp won't make enough power. My experience with factory speakers is that they don't have the range or power handling of aftermarket units. Personally, I'd ditch the stockers. With speakers in the stock locations and in the kicks, you'll have some imaging issues too. Kick panels are the way to go though...

Cebby

Sorry, Noel. I was composing and watching TV and didn't realize you had responded.:pat:

williemon

If you reduce the amp gain on your front, then it would better match the rear, and also would not pass as much current, but that may or maynot help if you listen at a volume that could call for an overcurrent situation in the amp. Rember, if you half the resistance to the amp, you double the current flowing through it. Some amps dont run well like that. You could run one set of fronts and the rears in series to 1 amp, and the other front set on its own amp, or both fronts in series. In any case, if you do run in series, yes that makes resistance at 8 ohms and power output will be cut in half from that amp, but that translates to a 3db cut in percieved loudness, which actually is very little. Doubt you would even hear a difference. If you dont call upon the amps to squeeze every db of juce from them then it would be a moot point. Being an audio fanatic, I tend to use an amp to its max ability. Not for sheer volume, but to have headroom for the undistorted peaks I want in the music and the non muddy bass. Have fun. Thats what its all about. Later.

HaveBlue

This brings up another question:

How do I reduce the resistance?
On a 2-ch amp, do I run two wires out of each channel to each speaker? Or do I run one wire to one speaker and another wire from that speaker to another?
Does anyone have pictures?

WILL SOMEONE PLEASE HOLD MY HAND?

Oh yeah! Another question:
I am looking at a Sony 4-ch amp. The specs say 75W x 2 + 200 x 1 @ 4 ohm. Does this mean I could power my two rear speakers and my single 12" sub with one amp?

Thanks again!

Churnd

75x2, for 2 speakers and a sub? definitely not. besides... unless your amplifier has 2 different filters, you can't drive a speaker w/ a tweeter and a subwoofer.

Cebby

I think HaveBlue's other amp he is talking about is a bridgable 4 channel amp (hence the 75wx2 +200x1). He could use that on the rear and sub. If it is bridgeable, there is probably a filter in the amp - depending on vintage... If not, maybe an electronic xover or coil...

I'll see what I can dig up on wiring for you. I could try to explain it, but a picture will make it very obvious.

Cebby

Here is a link to an article by a well respected individual in car audio (I met this guy at a contest years ago).

Series vs. Parallel Wiring Article and Diagrams

Sorry in advance about the pop-ups on that site...

4FonZ

Hey HaveBlue... That's exactly what it means.

You can take that amp and power 4 speakers (4x75 should be) like 2 fronts and 2 rears...

Or just do 2 fronts and 1 sub... Channels 3 & 4 will go to the sub... bridged... if it presents a 4 ohm load.. you have to look into a sub that is DVC dual voice coil @ 2 ohms .. somethin like that..

HaveBlue

GREAT! After reading that website, I am more edumacated
THANK YOU!

So, for the front 4 speakers, I will want to wire them parallel from each channel (2-ch amp) and parallel in the rear from one channel and bridged to the sub (4-ch amp)?
On a 4-ch amp, can I bridge twice. For example, can I bridge to the sub and bridge to run the rear speakers in parallel?

Cebby

Bridging gives you mono output. Keep the rears in stereo and bridge mono for the sub.

rowan

speaker stuff can be confusing. i read most of that site and it was pretty good. i have a single 500 watt, 4 ohm 10" MTX sub. should i just get single channel 500 watt amp thats 4 ohms?? or a 2 channel 250 watt amp and bridge it. i dont even know what bridging means for sure... well i need an amp so if any of you smarties know what to get that would be good.


ahha sorry for asking a question on your thread good luck with your system. if i dont get help here i guess ill start a new thread. thanks.

Cebby

That speaker is probably rated for a maximum input of 500 watts. You don't need to (or want to) get an amp rated for 500 watts continuous output. Get something that is around 300 watts so you have some headroom... What kind of music do you listen to?

rowan

yeah ok, a 300 watt amp sounds better (Cheaper too)

i listen to all kinds of music. rock, old stuff like the doors, hendrix, etc,... basically everything.. techno, rap, you name it. id even listen to classical, if i had some CD's.

Cebby

You definitely want to leave some headroom with such a diverse music selection. You'd be surprised, but Classical can really torture a system. I like pretty much everything, too. Two types I don't care for are Country and Western Sorry to those who like that stuff, but it's not for me.

Vato Loco

Is this going to be enough power going to 2 10"

Kenwood Subs with this Kenwood Amp? This is my sub set up only, are these subs going to be loud?

Cebby

More than enough. I had 4 Boston Pro 10's in an infinite baffle setup driven by only 150W (1/2 of a 4 channel amp bridged into 4 Ohms) and I could hit 128 Db. It will be plenty loud, but there are a few things to consider. You can wire that up a couple of different ways. The subs you are looking at are 4 Ohm, single voice coil. You can run them one per channel in 2 channel mode (100 watts/ch @ 4 Ohm) or you can bridge the amp and run them in parallel. The amp is 2 Ohm stable and develops 600 watts (peak at 14.4 v) this way. You run the risk of cooking the speakers if there is a brutal peak in the music - just don't crank the gains on the amp. You'll want to have some beef in the system to help deliver the power - 4 guage (at least depending on the rest of the system) power fused by the battery and fused again before the amps, 12 guage speaker cable to the subs and a capacitor in line with the power cable to the sub amp to help with the transients. Make sure you build the sub box to the manufacturer's specs. If you are only going for loud, here's a couple of thoughts: Ported enclosures are louder than sealed; and more cone area is always louder. What are you doing for the mids and highs in your system? Are you a big Kenwood fan?

prerunner guy

look, just take the weakest speakers you have in the truck and run those solely off the head unit. then, take the remaining 4 speakers and run them directly to the speakers. The head unit's power will all go to the speakers hooked up. The 2 2 channels amps will power the four speakers then. There is no need to run 6 off 4 channels. That is not the smartest thing for quality. Do what I said and you will be happy.

prerunner guy

AS far as the 10" mtx sub goes, get a 500 watt amp that has around 300 watts rms. The 500 will give you the peak power capabilities but the rms is the continuous. Jensen makes a decent one and kicker makes a good one. Don't get a 300 watt amp because that will only be 150 rms.