Just want to know how do you tell if your amp is send clipping signals to your speakers?

Heres my problem I connected my 2 Diamond Audio 6x9's (which are 70-120rms) this weekend to a phoenix gold zx475ti amp, the amp puts out 75x4 @4ohms I have the amp gain set about 2/3 and at full range & bass boost is at 0. Now everytime I turn the volume up to 40 (the max volume is 60) the speakers sound like there getting muffled and distorted is this because of bad tuning or is there something wrong with the amp. The other 2 channels on the amp are still left open waiting to hook up a sub.

I have a PG 600.2Ti 2 channel amp running my DA hexs s600s the gain is also set at about 2/3 and I have no problem with distortion or anything

 

It depends on how serious you are about it. I purchased an oscilloscope off of ebay for a low price and bought a level-setting cd from David Navone and set the gains perfectly with no clipping, but maximum output. All the equiptment could cost less than $100.

 

^^^^^ Thats really the only way to do it.... When the clipping first starts you will not be able to audibly hear it.

 

quick simple way to get you in the ball park is to:

1. turn the gain on the amp all the way down.
2. turn up the volume to just below full, usually a couple of numbers down.
3. slowly turn up the gain on the amp until you just start to hear distortion, thats too much. back it down about a 1/8 or 1/16.

that should get you in the neighbor hood and protect your speakers from damage.

 

What is the cause of my speakers getting muffled? I'll play a CD for about a minute and the speaker begin to get low and sound muffled when amp is about 2/3 of the way up. What I don’t understand is the amp puts out 75rms and the speakers can take up to 120rms. If I keep the gain a little below 1/2 way I don’t have any problems, but the speakers aren’t even that loud when the gain is at 1/2 way, I know they have a lot more potential.

 

just curious what causes clipping.

 

Clipping is caused by over driving the input of the amp. If the amps max input is 1.0v and you apply a 1.25v signal the top of the signal will be 'clipped' off. The closer you get to maximum output of the amp the more distortion you will get. When a speakers signal is cliped the signal rises like normal and then 'flatlines' at the max level before lowering back down. You whould be able to find pictures of this on the internet (o'scope pics that is)

 

http://www.st-andrews.ac.uk/~www_pa/...pping/fig1.gif

http://www.science.smith.edu/departm...ppedspikes.gif

There are a few pics of what clipping looks like

 

Back to your problem....

You say you have another PG amp installed. I would swap the rear speakers and the front speakers at the amps. If the problem continues with the rears you need to look at the speakers, if the problem goes to the front speakers the problem is with your amp (or somewhere before it).

The only way to diagnose a problem like this is by process of elimination, and since you already have an amp installed it should be rather easy!

 

thanks for all your help. First thing Im gonna try is switch to High Pass instead of Full Range. Take a look at the pic attached it is the frequency control dial what should I set it at for the 6x9's? theres also a black push button right next to the frequency dial that says 10x what is this for and should it be on or off when I switch it to High Pass?

Thanks for helping me out with my problem

 

The 'correct' setting would depend on the entire frequency response of the system. The 10x button would NOT be used in this situation, as you have a full range speaker being used.

To set your crossover frequencies you need to know what frequency the speaker is capable of reproducing without a large amount of distorition. The problem with this is that NO manufacturer will post this information because it depends greatly on the quality of the amp being used. Another factor to consider is the frequency that other speakers are playing at. If you have a sub playing from 30 - 120 hz then you would want your next set of speakers (technically a midbass) to start playing around 100hz (slight overlap is always nice to prevent hearing 'gaps' in the frequency response). Most 6x9s will not play down to 100hz reliably, especially at high wattage.

Another method of setting it is to start about 250hz and slowly turn the dial down while the stereo is playing a track with a good bass note. You should be able to audibly hear the speaker start to distort at a certain point, then dial it back up a hair.

 

is that 10x frequency button only used for when running components?

 

Its for the high pass filter... high pass filters generally run in the 5-10Khz range. So, you push it in and the value given on the dial is increased ten fold.

 

Or your amp could be a lil powerful than you think, and the gain is just too high...my recommendation is turn the gain down a bit more and see how much better it gets a louder volumes.