I have an Alpine CDA-7875 (60x4 max, 27x4 rms I think) and Polk EX components all the way around in my TII. First question is, who thinks moving the front 4" speakers from the dash to the doors would help in terms of getting a better sound from them? I know my shins like hearing the music well, but I think I'd rather my ears got the better end of the deal.
Second question would be, these speakers can take quite a bit of power yet they distort at anything over 1/2 volume. Is this just because my deck cant give them the power they need? Thanks for any help

 

bump

 

If you want to add more sound, i would add 6.5s to the doors instead of moving the 4s over. If you want to do that, there are some companies that make a 3 speaker component set. For example, MB quart PSD316 has a 6.5" + 4" and a tweeter for $520+, but they are awesome speakers.

Your speakers are distorting because yes they are underpowered. If you had some lower end speakers they would be fine, but the ones you have I would give them the RMS they want.

Good luck with what you go with.

 

I've got the MB Quarts in my 91 Miata.....Awesome!

Got Boston Acoustic Pro 6.5's in my 3rd gen doors with Boston Acoustic Rally 6's in the rear and 8" Vega sub-tube under the rear strut brace

Can't get much better than this!

 

I'm currently not financially able to buy new speakers, but in the future I probably would go for that MB Quart setup as well as an amp or two.
For the moment though, would just moving the 4" speakers I have now to the doors give any significant advantage? Thanks for the input so far!

 

No. With moving the 4 inch into the doors there would be no advantage at all. On that car the biggest advantage will be in adding 6" speakers to the door to work in concert with the dash speakers.

If the Polk 4 inch speakers are distorting they need to be crossed over (at least 200Hz at a 12dB slope) or you need to send less bass too them. The 30 watts a channel RMS that that deck will do (properly wired) is more than enough to drive those speakers to peak.

With those little speakers your BBE should not be over 3 and your Bass engine center freq should be 80Hz or higher. Of course again properly crossed over and you could lower the bass center freq and increase the BBE (or MX/loudness if your deck has that).

 

The RMS rating on the 4" speakers is about 100 watts and the 6.5 rear are about 140 so both sets do seem to need quite a bit more power. It seems a good 4 channel amp is next on the list. Any recommendations?

*edit - After looking up the actual figures, I could only find max figures being that the 4" maxes at 130 and the 6.5s max at 160 so my RMS "figures" were slightly high. Still, you get my point. They need more power*

 

You and LoSRx7 are wrong thinking that the problem will be solved with going with an amp. Maybe on the rear speakers, but not the front until you add 6 inch speakers into the door.

Even the best sounding Polk 4 inch speakers have an average power handling of only 35 watts. That deck easily puts out that.

According to Polk (http://www.polkaudio.com/car/specs.p...18&speaker=115)

the 4 inch EX speakers are rated at:

Power Handling (continuous) 35 watts

and have a Overall Frequency Response of 90-22kHz.

So if you are trying to run any freq under 80 hz you will blow them, and if you really crank that deck for long periods of time you blow them.

That's why they sound crappy. You are just slightly under the average maximum power and you don't have them crossed over right?

 

The fronts sound pretty clean actually. The rears are the ones im getting the distortion from.

 

Have you checked to see that the rear ones are in phase?

They also do not have a great low freq range (Overall Frequency Response 55-22kHz) and they to will sound distorted with the BBE being over 3 and the bass setting being up at all.

 

Hmm... I have both high and low crossovers built into my deck so It looks like I need to set that for just above 55 for the polks. Would you advise picking up a sub for low end punch or should I just sell the polks for some speakers with a bit more low end to them?

 

That deck does not have a built in high pass crossover, it has a varible boost point. If it has a RCA sub-woofer output (which I didn't remember on that older deck if it did) the built in crossover is only low pass. Meaning only low freqs are sent.

On the front and rear channels, they are full range; no matter where you crossover the sub output at.

A sub will sound night and day better than the polks but you will have decide if you want to give up the room and money.

 

I do know my head unit and it does have both low and high pass filters. It will cut freqencies as low as 80 on the high range and will cut them as high as 160 on the low range I beleive