4channel amp question, please look!

M

mr_tinkertrain

Member

Dec 14, 2003

151

0

16

Hot Springs, AR

Jul 13, 2004

#1

• Jul 13, 2004

• #1

Ok wanna put in a 4channel amp to power my 2 rear and 2 door speakers. leaving dash speakers powered by head unit for now. alright all 4 speakers are 4 ohm loads so if tahts all combined it would be a 1 ohm load correct? so if the manufacture says it puts out 100watts rms @2 ohms then taht means its not stable at 1 ohm correct? then i'd blow the amp if i hooked it all up.......maybe i just need some teaching cuz thats how i thought it worked. p.s. can i put new fuseholders after a distribution box or should i just put one fuse up by the battery and thats fine?

 

MyEarsHurt

New Member

May 21, 2004

918

0

0

Jul 13, 2004

#2

• Jul 13, 2004

• #2

Well, I will give you a few of my experiences/suggestions on this because I was planning on doing a similar setup in my last car. Having one set of speakers run off of a head unit, and another set of speakers run off of an amp is generally speaking a bad idea. When its just bass, its not a big deal, but when you are talking about a set of 2 ways then chances are pretty high that you will get a little bit of echo. It may not be that bad, but the speakers powered by the head unit may give off a sound 0.09 seconds before the other speakers (I have no idea on the exact time, it would depend on a lot of factors). Even a small difference between the two would sound odd, and not make very good sound quality, I have heard it happen before. As for wiring the 2 ways in 2 ohm or 1 ohm, I would not do it. Most 2 way speakers are designed to play in 4 ohm, and if you drop the resistance, you could lose quality, or blow the speaker coil. I would save up and get a decent 4 channel to power all the speakers. As for the fuses, you really can never have too many. I have one 80 amp fuse near my battery, and a fuse distro block in my trunk, which feeds my two amps, and it has 2 60 amp fuses.

 

M

mr_tinkertrain

Member

Dec 14, 2003

151

0

16

Hot Springs, AR

Jul 13, 2004

#3

• Jul 13, 2004

• #3

i really dont know alot about this kinda thing but i have a different view on the ohms thing but i know i could be wrong. i am a newb this is just my understanding of it. I thought that your amp could only handle so much of a load and that your speakers and the way your speakers are wired is what determines the load on the amp. so the speakers are still getting their 4ohm loads, but the amp would be putting 4ohms to EACH speaker making the load on the amp 1ohm........as i say this i really dont think i'm right. thats how i thought it worked. you dont lose quality when you wire a dual voice coil sub in parallel thus decreasing the load on it so why would speakers be any different? i'm not saying your wrong, i'm saying this is how i thought it worked. if anyone can explain this more to me please do. but what do you mean by higher quality amp? the one i was thinkin of is a newer rockford putts out like 100rms X 4 @ 2ohms and 50rms X 4 @4ohms. thats good quality isnt it? i am so confused right now......

 

M

mr_tinkertrain

Member

Dec 14, 2003

151

0

16

Hot Springs, AR

Jul 13, 2004

#4

• Jul 13, 2004

• #4

btw i've never seen a 4ch amp that says 1ohm ratings on it so i dont know what to do.

 

grodgers

Member

Aug 21, 2003

178

0

16

Plano, TX

Jul 14, 2004

#5

• Jul 14, 2004

• #5

mr_tinkertrain said:

Ok wanna put in a 4channel amp to power my 2 rear and 2 door speakers. leaving dash speakers powered by head unit for now. alright all 4 speakers are 4 ohm loads so if tahts all combined it would be a 1 ohm load correct? so if the manufacture says it puts out 100watts rms @2 ohms then taht means its not stable at 1 ohm correct? then i'd blow the amp if i hooked it all up.......maybe i just need some teaching cuz thats how i thought it worked. p.s. can i put new fuseholders after a distribution box or should i just put one fuse up by the battery and thats fine?

Click to expand...

to answer your question - no, it is *not* a 1-ohm load. It'll be between 4 and 8 ohms per channel (most stock speakers aren't 4 ohms - but higher).

If you buy a 4-channel amp, the load stability is rated "per channel" - therefore you'll be fine.

 

B

bigb64

Founding Member

Aug 15, 2002

73

0

0

madison heights, michigan

Jul 14, 2004

#6

• Jul 14, 2004

• #6

I belave only class d amps are one ohm stable (mono amps) and yes you can hook up to the distrobution box and have a fuse afterwords.

 

M

mr_tinkertrain

Member

Dec 14, 2003

151

0

16

Hot Springs, AR

Jul 14, 2004

#7

• Jul 14, 2004

• #7

alright thanks for the info grodgers and bigb64. i'll get an amp that puts out 100x4 @2ohms and i'll be set...may just unhook my dash speakers as they are only 3 1/2 neway.

 

Jester73440

New Member

Jul 14, 2004

45

0

0

Jul 14, 2004

#8

• Jul 14, 2004

• #8

is that 100x4@ 2ohms? and the rule about fuses is that you add a fuse everytime you change the size of the wire and keep the 1st fuse as close to the battery as possible

 

Mystifier

New Member

Aug 7, 2003

24

0

1

Lynnwood, WA

Jul 15, 2004

#9

• Jul 15, 2004

• #9

mr_tinkertrain said:

alright thanks for the info grodgers and bigb64. i'll get an amp that puts out 100x4 @2ohms and i'll be set...may just unhook my dash speakers as they are only 3 1/2 neway.

Click to expand...

Keep in mind that unless your door and rear speakers are rated at 2ohms you will not be giving them 100w each. If your speakers are rated at 4ohms like you stated earlier they will be getting 50w each with this amp you are planning on using.

 

M

mr_tinkertrain

Member

Dec 14, 2003

151

0

16

Hot Springs, AR

Jul 15, 2004

#10

• Jul 15, 2004

• #10

but with two 4 ohm speakers wired to one channel that'll make it a 2 ohm load...right? god this is confusing stuff.

 

Jester73440

New Member

Jul 14, 2004

45

0

0

Jul 15, 2004

#11

• Jul 15, 2004

• #11

wired in parallel yes, if your amp is:
100w X 4 channels at 2 ohms- wires each speaker to a channel this will give them about 50w a peice that is all you need to give them most full range speakers are only rated for 40-75w so 50 will be plenty

if your amp is :
100W X 2 channels at 2ohms- Then wire the 2 left speakers in parallel(both + to the + of the amp both - to the - of the amp) to the left channel and both right speakers to the right channel in parallel this will give you 50W to each speaker

i never heard of an echo effect but powering 3 1/2@7-12W would be kind of usless if you do put a bass blocker on them and keep them at high HZ

 

M

mr_tinkertrain

Member

Dec 14, 2003

151

0

16

Hot Springs, AR

Jul 15, 2004

#12

• Jul 15, 2004

• #12

good info jester thanks! maybe i could get 2 ch amp for better power to each speaker and probably cheaper too. i guess you have to wire left and right side on different channels so its in phase? seems like i've read something bout that before. thanks though!

 

Jester73440

New Member

Jul 14, 2004

45

0

0

Jul 16, 2004

#13

• Jul 16, 2004

• #13

keeps it in stereo instead of mono