Can somebody explain this to me

[Ben P]

In my car I am running:

6" front components amped by Alpine 2 channel

4 x Sony 6x9s amped by Sony 4 channel

2 x 12" RM subs amped by Vibe 2 channel

Everything is fine except with the front components. As you might expect from this system there is loads of sound in the rear, so to compensate I had planned to run the rear amps at slightly lower levels than the front.

Heres my problem. My front components are Infinity 605s and are rated at 90W RMS or 240W Max. The Alpine amp that drives them is rated at 2x55W RMS or 2x120W Max. I thought that this would mean I could run the amp at full level output without any risk of the speaker distorting or blowing. But even with the amp level set at half way, the front speakers start to distort at volume level 28 on the head unit. (Goes up to 30 I think)

It wouldnt be so bad, but I can run the rear 6x9s at full amp level and they still dont even hint at distorting even with head unit volume at full.

Any ideas? Am I being thick?

 

[CS_Matt]

are u tryin to run bass through the front aswell?

my suggestion would be to run the subs for the bass and only run treble through ya other speakers, they shouldnt distort just by running treble through them

 

[viceroy]

Possibly its the amp distorting since youre running it at full level output. Try dropping the output level to say 80% and try again.

I always try match my amp and speakers to so that the amp at 100% is 80% of my speakers max output. eg 80W amp with 100W speakers and even then I only run the amp at 80% max. This little formula has always held me in good stead

 

[Tom]

its the head unit what make is it?

bet its a jvc or a sony

 

[Rick]

Your better off using an amp with an equal or higher RMS rating than the speakers, not vice versa. A bigger amp will be able to produce the same power as your current one while still working well within its own capabilities, therefore not producing distortion.

Rick

 

[Ben P]

OKay cheers for the replies a couple of answers.

- the head unit is a 4x50w Panasonic 701 job, not a piece of crap

- I am running the subs from 1 amp, and bass through everything else as well otherwise it sounds too flat

- In respect to the speaker/amp rating my amp is rated at 2 x 120 max the speakers are rated at 240w max

Its so annoying because they are supposedly decent components.

 

[luke.B]

it sounds like the problem you have is that the 6 x 9s are alot more efficiant than the components, also as you are running 4 6 x 9s then the components will never keep up. the infinitys are a quality speaker but can only play so loud as they are desigened for good representation of sound. try putting the high pass filter on your alpine amp on take away the bass from the front and it should sound better, if it still dosent sound loud enough try turning down the amps to the 6 x 9s and the fronts, remember that the controls on your amps are only gain settings so turning it down doesnt mean that the power to the speakers has been reduced so try both at about 3/4 gain then play with the fade on the head unit (only possable if you have a seperate sub out rca). It is not normally recomended to have the gain settings on full on your amps as the further up the gain is the lower the quality of the sound. If all of this fails to stop the front speakers distorting then look at changing the front speakers, but it shouldnt come to that.

Hope this helps



Luke



Hope

 

[luke.B]

oh forgot to mention that the reason you dont wwant to run any bass through the front is that they are not designed to play at that frequency so they will distort alot sooner if they are being forced to play bass.



Luke

 

[Ben P]

Cheers Luke

I will try your suggestions and yes I have a separate sub RCA out

 

[dann172]

An amplifier will never produce a perfect signal at 100% of its gain...its just not going to happen....drop the gains down before you knacker your speakers....

 

[Ben P]

Just to clarify I am not running my amps at full gains, more like half way.

The problem is my front speakers distort at anything higher than this, whereas my rears could run on full if I wanted to.

 

[dann172]

I see...but if your pushing the head unit really high then one would think the signal to the amps would not be at its best.....your better off lowering the max head unit volume and increasing the amp gains....just a thought....

 

[Ben P]

okay ii turned off the bass for the fronts which has allowed me to up the gain and thus keep my head unit volume lower.

much better than before thanks to all!