Component location problem

[ahammond 0]

I need help troubleshooting a new speaker install/upgrade. I just installed Boston Acoustics in front and rear. SR60 6.5 components in front and SR95 6x9 in the rear deck of a 96 Impala SS. The problem is now the rear sounds much flatter and the front is way too bright up high. These were upgrades to 12 year old Boston 6.5s and Pioneer 6x9s. Old speakers sounded fine but I wanted better sound and a bit louder. Old speakers were 50w rms and new are 80-85 rms. Amp is 100x4 rms and I also have on a seperate 450w mono amp a 300W Pioneer 10' shallow sub in a sealed box inside the cabin, not the trunk. Location of the 6.5 components up front are, woofer mounted in the door stock location about ankle height and the tweeter mounted in the base of the pillar molding facing directly across the dash at each other. With the old 6.5 components the highs were not very bright but with the new SR60s mounted in the same location it is very very bright. I have even set the jumpers in the crossovers to cut the tweeters -4db and the HU is cutting another -4db off the treble setting, this is what makes the rear sound too flat or hollow. The car has always had a hollow sound in the middle of the car. When driving you can lean forward 4 inches and the front sounds much louder, if you lean 4 inches to the rear the back sounds much louder, it is like the middle of the car is between the front and rear fields or the two fields are tonally different. This is why I choose both front and rear from the same brand this time, I would have thought they would sound good together, not the case. Also I went up to the next level of the Boston product line, they are not the Pro60SE simply because they were too expensive. I have double checked the polarity of all speaker wiring several times, + is + and - is -. Any advice or help in correcting this would be great, other wise I may just have spent 700.00 for nothing and have to put the old setup back in. Would angeling the speakers differently help, if so how is this done. Would changing the tweeter location to the door next to the woofer down low be wise? What would you try?

[///M5 2,833]

You forgot to describe the MOST important thing, the install. I doubt that the equipment was your problem, but how you put them in.

[ahammond 0]

I'm not sure what you are meen the "install', location or mounting? I think the problem is location but I just wanted opinions on where to try moving the tweeters to so they aren't so in your face. As I said originally " Location of the 6.5 components up front are, woofer mounted in the door stock location about ankle height and the tweeter mounted in the base of the pillar molding facing directly across the dash at each other." The tweeters are mounted in the cups that came with them in a hole cut out of the pillar plastic molding, is there a better way? Thats all I have ever seen done. I didn't think that how a tweeter is mounted affected its sound, just location and aiming. Woofers are mounted to a flat mdf baffe in the factory location but aimed directly across the vehicle at the other side, same as the tweeters, aimed directly across at the other speaker. I would think that aiming the tweeters at the vehicle center or driver/passenger is going to make them sound louder and higher still. The problem is that the tweeters are just louder than any other speaker, even when crossover jumper set at -4db. 6x9s are just dropped into the factory location in the rear, it had a foam seal between the rear deck and the speaker so I reused it.

I am looking at two problems here. Front tweeteers over power any other speaker and there is a hollow empty feeling in the middle of the vehicle between front and rear sound fields. Any help is much appreciated.

[altoncustomtech 773]

You'll want to experiment by moving the tweeters around the front of the car. Every speaker set is different, even from the same manufacturer. The same locations hardly ever work for one set from another. Give them some long speaker wires and use a bunch of velcro pads and stick them in different spots, with different aiming. ALSO be sure to try switching the phasing on the tweeters. You'd be surprised at how easy a fix that can be to a tweeter or two that's just too bright. I currently have everything in phase in the front of my Jimmy EXCEPT the passenger tweeter cuz it just screamed. Switched the polarity on it and not only was it not as bright but the sound stage lifted and shifted back to center and everything leveled out and sounded exactly like it should.

[///M5 2,833]

I'm not sure what you are meen the "install', location or mounting?

If you just bolted them where the stock ones were without any other work that is definitely the problem.

[ahammond 0]

I'm not sure what you are meen the "install', location or mounting?

If you just bolted them where the stock ones were without any other work that is definitely the problem.

M5,

I would really appreciate your opinion since everyone on this forum thinks you know your stuff but did you even read what I posted? I did not simple bolt them in the stock location without any other work.

Stock speakers were 4x6 mounted in the bottom front corner of the door, they were replaced the first month I owned the car back in 1996. At that time I put Boston 6.5 SC components, now I have purchased the next level up in the Boston product line, the SR60s. Tweeters are not mounted in the door with the woofers, they are in the base of the pillars just above the dash pointing straight across the dash at each other just as they have been since 1996. I don't understand why they are so loud as compared to the next level down, the old SC60s. The woofers are mounted in MDF baffles but are pointed srtaight across at the other woofer. Would angleing them someway help change the empty hole in the middle of the car? Where would you move the tweeters to, down by the woofer?

I haven't tried the previous suggestion of polarity change of the tweeters because of weather but I plan to try that soon as I can. Any other suggestions that I can try at the same time?

[///M5 2,833]

No, I didn't hardly read what you wrote. I asked for some specifics which you then responded with a bunch of other stuff regarding wanting an opinion on location. No way in hell can I comment on a different one with the background you've given us so far. Re-reading, I realize you added that they are screwed to a piece of mdf. Not really very complete. Describe what you've done, what you have, and so on. Otherwise it is impossible to help.

Pictures never hurt either.

Play with more than just the tweeter phase...

[ahammond 0]

No, I didn't hardly read what you wrote. I asked for some specifics which you then responded with a bunch of other stuff regarding wanting an opinion on location. No way in hell can I comment on a different one with the background you've given us so far. Re-reading, I realize you added that they are screwed to a piece of mdf. Not really very complete. Describe what you've done, what you have, and so on. Otherwise it is impossible to help.

Pictures never hurt either.

Play with more than just the tweeter phase...

Man I'm truly sorry, but I don't know how else to describe the details of this problem. I have given all the specifics I can think of. I have stated the equipment I have, even given model numbers. I have stated the exact location of each speaker component. I have stated exactly how each speaker component is installed. I have stated the two problems, over powering front tweeters and how the vehicle seems to have two seperate sound fields front and rear with the middle having a 'hollow' sound.

If there is more information that you need to help me I would truly be happy to give it to you but I don't know what that would be.

So I guess thats it, I'm sorry if I wasted you time......

[ryan s 12]

If I understand correctly...

Sounds like the tweeters are creating early reflections off the dash, the windows, or the door panel. Can you hear "phantom" sounds at certain frequencies?

Either reverse the polarity of the tweeters relative to the mids, or move the tweeters elsewhere. Since they're already off-axis...and already EQ'd...your only choices are polarity reversal or placing them more off-axis.

My tweeters are mounted coaxially with the mids in the doors. Sound height aside (it's only at neck level or so), the tweeters are aimed dang near directly into the seats. That rotation alone cut down on harshness and apparent beaming 20-fold.

As for the dead zone in the car...have you tried running without the rear speakers? Angling the mids won't help a lot, since they barely play in the directional frequencies (~1600Hz) before the tweeters take over...depending on the passive's XO frequency, that is. I think it's due to the fact that the front isn't playing the mids loud enough since you "can't" turn them up relative to the tweeters.

Also, can you bridge your amp/run one channel to each driver? That may help due to increased power. The passive XO saps power and add "character" to drivers that may not be desirable.

[ahammond 0]

Ryan, thanks for your time. As you and Alton suggeted I reversed the polarity on both tweeters tonight, it did help a bit but not quite enough, the louder it is the worse it is. As much as I hate to since I already have the holes cut in the pillars from the previous installed components I will try other tweeter mounting locations and angles as soon as I can and maybe see what effect reversing polarity on only one tweeter has on the sound field . You are probably right about the reflections, while I had them out of the mounting cups I placed them on the dash facing straight up at the windshield and they were just as bright and over powering as before the polarity reversal. I am using an amp that is 4 channel x 100 RMS and the front components are rated at 85W so I think they are not under powered. I can raise the gain on the front 2 channels so they are getting more than the rear and see what that does. I have a seperate HiFonics 450W x 1 for the 10" sealed sub in the back seat . When I run the fronts only, it sounds like the music is several feet farther in front of me than the speakers are which is probably why there is such an emptiness in the middle of the car. I really hope I can get this solved, its pretty frustrating.

[ryan s 12]

Hmmm...that last part is interesting. For those of us obsessed with our "front stage" one of the goals is to get the sound to appear as if your car doesn't have a windshield or windows...a wide stage, if you will. Kind of like sitting 10 feet from a pair of speakers is infinitely better than sitting 3 inches away.

If your amp has enough crossover abilities (high pass filter on channels 1 and 2 at ~80Hz, maybe a low pass around 2Khz...and a high pass on channels 3 and 4 from 2-5Khz...) you can run that amp on on the fronts only...one channel per speaker. I've seen more than one review where people wrote that running without the passive crossover supplied with the speakers changed the character of the tweeters dramatically.

Of course...it requires another run of speaker wire for each tweeter to the amp, and an amp which has the correct values of XO points...but short of a new component set, it might be worth a shot. Otherwise, you could use some type of foam over the tweeter to try and tame them.

Oh by the way...I wonder how much the doors are at fault for "losing" sound. The MDF baffles need to be sealed so the back waves of the speaker don't conflict with the front waves. Also, I bet you have a huge hole for the window regulator...if that was sealed up, the mid would sound better. The sound definitely seems to be left behind...somewhere...since you're giving them decent power and they're mounted to a good baffle.

[///M5 2,833]

I'd try throwing a HUGE dash pad up (ie a comforter or something) and see if it is the tweets or the reflections that are driving you nuts. Cover as much of the dash and as much of the incident windshield as possible.

I also tend to listen to drivers on their own when I am trying to solve problems. Mixing with the mid may be a fault of the crossover design, but such that it doesn't work in the alignment in your car.