Speaker Question

[Joe Isuzu]

OK, need some input on a speaker problem I'm experiencing. I completed a sound deadener project and figured while I had the inner quarter trim and door trim panels off, I would replace the speakers. I used the same size so there was no modifying needed. They're done and now I am getting what seems like an echo effect from the rear speakers, right more so than left. I've taken off the inner quarter trim twice now to make sure the connection is good. It seems to be more noticeable when people are talking on the radio than when there's actual music. I've replaced speakers before on a number of different vehicles and not experienced this before. Bad speakers? Any thoughts would be appreciated.

[etlsport]

what kind of head unit do you have? there could be some sort of delay on it... also maybe try switching the speakers and see if the problem switches sides.. i dont think this would have an effect.. but do the new speakers have tweeters that stick out? maybe they are hitting the grille of the panel that sticks back quite some ways.. dont know why that would give an echo sound.. just tryin to think of the problems i had with my rear speaker install

[Triathlete]

Did you try reversing the polarity?

[Y33TREKker]

Did you try reversing the polarity?

That's the first thing that came to mind with me too. The easiest way to ensure correct speaker-wire-terminal/speaker-wire polarity is to put a 9-volt battery (the small square ones) across the speaker leads. When applying the battery across the leads makes the speakers' woofer push outward, the positive battery terminal is on the positive speaker terminal. Check all the speakers just to be sure.

[PHO2GR4]

IItt''ss pprroobbaabbllyy jjuusstt iinn yyoouurr hheeaadd.

Kidding. It's probably the polarity. I never knew about the 9-volt battery trick, though. Nice one!

[IndianaVX]

Joe,
just throwing this out there too, but i have noticed on a couple of stations here in indiana, there is a bugging kinda echo on their broadcasts this is on FM radio.......but im wondering, these same stations are broadcasting in "HIGH DEFENITION"
so maybe thats it. i have noticed alot of overlap too in stations, another station just faintly in background, while list to another........... not really an echo on that one though.....

im assuming by your post that you dont hear/notice the echo when playing cd player, only when listening to radio........

[Joe Isuzu]

Wow, ask a question get 5 responses, this is a great forum!
OK, one at a time
The head unit is the OEM Isuzu one, I crossed that out as a problem b/c I don't recall the OEM speakers having any difficulties (other than sounding a little worn)
With respect to whether the rear speakers have a built-in tweeter, I don't believe they do, the way I understand it, I have 4 woofers and 2 tweeters with the tweeters being up top on the door panels
I don't imagine there is any contact between the speaker and the grill located in the 1/4 trim panel itself so I don't think that's a problem
Lastly, with respect to polarity, I bought special adaptors from crutchfield that would hook up easily with the oem ones, as far as my understanding goes, I don't believe you can switch the polarity inadvertently as the connectors wouldn't work
Believe me, if the speakers were easier to access at all, I would be more than willing to try that anyway, but seeing as how everytime you fiddle with the trim panel you invariably break one or more of the plastic fasteners as well as the fact that it's just a pain in the butt to get to, well I will just assume everything is ok as far as connectors go :(

[Ldub]

Wow, ask a question get 5 responses, this is a great forum!
OK, one at a time
The head unit is the OEM Isuzu one, I crossed that out as a problem b/c I don't recall the OEM speakers having any difficulties (other than sounding a little worn)
With respect to whether the rear speakers have a built-in tweeter, I don't believe they do, the way I understand it, I have 4 woofers and 2 tweeters with the tweeters being up top on the door panels
I don't imagine there is any contact between the speaker and the grill located in the 1/4 trim panel itself so I don't think that's a problem
Lastly, with respect to polarity, I bought special adaptors from crutchfield that would hook up easily with the oem ones, as far as my understanding goes, I don't believe you can switch the polarity inadvertently as the connectors wouldn't work
Believe me, if the speakers were easier to access at all, I would be more than willing to try that anyway, but seeing as how everytime you fiddle with the trim panel you invariably break one or more of the plastic fasteners as well as the fact that it's just a pain in the butt to get to, well I will just assume everything is ok as far as connectors go :(

Just a thought...

Rather than reversing the polarity at the speaker, pull the HU (much easier) & reverse it there.

[Joe Isuzu]

ok, I had a relevation after my volleyball league tonight, I misunderstood the original advice about the polarity, the connector from the VX wiring to the speaker wiring should be fine, however, the wiring from the connector to the speaker may be switched
but I always thought that one of them (positive or negative, I can't remember which) was so much bigger than the other that you couldn't put a negative female on a positive male or vice versa
is this what you guys are meaning? that possibly the polarity is reversed at the speaker? or am I still off base here?

and LDub, I'm thinking if I reverse the polarity at the head unit, that will throw off my front speakers which are working fine, I'd rather have 4 good out of 6 than only 2. but thanks for the input anyway!

[Y33TREKker]

...that possibly the polarity is reversed at the speaker?

That would be the most likely spot where a reversal could occur, especially since you've used adapters to tap into the factory plugs. Although it's been awhile since I've done any stereo mods, most speaker wire I ever saw was either color coded (bronze and silver for example), or actually marked (+) and (-) on the insulation.

It would make sense that aftermarket speakers would have at least one terminal marked so that polarity was easily established, but I don't remember that always being the case, hence the trick of using the 9-volt battery to make sure.

The problem occurs when one side (say the back right) is connected one way, but the other side (back left) is connected just the opposite, making the speakers fire 180 degrees out of phase, and in effect, canceling each other out. (Not the most accurate technical description, but you get the idea).

It sounds like you just added rear aftermarket speakers? If the speaker wire from the adapters is marked (+) and (-), you could still use the battery technique to get the polarities correct and make sure each side is hooked up the same way.

[Joe Isuzu]

ok, I'll give it a try and let you know of the results, I just hate the idea of fiddling with both of those large trim panels just to access the speakers, ugh, oh well, guess I hate the idea of having sucky audio worse!
thanks again for all the advice to everyone who contributed

[Ldub]

ok, I'll give it a try and let you know of the results, I just hate the idea of fiddling with both of those large trim panels just to access the speakers, ugh, oh well, guess I hate the idea of having sucky audio worse!
thanks again for all the advice to everyone who contributed

OK, but I still think you could reverse the polarity on the HU end a lot easier...the HU has to be able to send a signal to just those speakers to control fade & balance.
You would have to switch them inside the wiring connection?

Still just thinkin' out loud... ;)

[mdwyer]

just throwing this out there too, but i have noticed on a couple of stations here in indiana, there is a bugging kinda echo on their broadcasts this is on FM radio.......

Oh, man. I took a road trip with a guy who worked in radio all his life. It was pretty educational. We swung up and down the dial comparing the sounds of the stations. The amount of processing that a typical radio station goes through is stunning. If you ever happen to find two stations playing the same song at the same time (which happens with depressing regularity... thank you ClearChannel.), flip between them and listen to the differences.

They tune the stations to the audience. Young males get more bass. Women get more midtones. ALL of them get louder. Small stations that can't afford all the equalization toys just can't compete!

Aaanyway, sort of a thread hijack, but I wanted to get back to the idea that it might be the radio station. I know KALC in Denver's studio bits sound like they're broadcasting from a bathtub.

Try a CD!

(Besides, polarity would cause the sound to cancel itself -- not echo itself...)