Rear Pioneer 1695's - no bass
I installed Pioneer 1695's in the front of my '02EX and was really impressed with the bass improvement.
Expecting similar results, I replaced the back speakers with 1695's as well. Unfortunately, the rears barely offer any bass improvement, so I'm disappointed.
When I installed the front speakers, I tried them both with and without "bass baffles". I found the that bass baffles totally killed the bass when they were installed, so I cut most of the baffle, using it only as a rain shield. I assume that this would be the same case if I tried them in the back.
Does anybody have any suggestions on improving the rear bass?
Expecting similar results, I replaced the back speakers with 1695's as well. Unfortunately, the rears barely offer any bass improvement, so I'm disappointed.
When I installed the front speakers, I tried them both with and without "bass baffles". I found the that bass baffles totally killed the bass when they were installed, so I cut most of the baffle, using it only as a rain shield. I assume that this would be the same case if I tried them in the back.
Does anybody have any suggestions on improving the rear bass?
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Keep in mind I haven't seen the back of the '02.... so I speak in more general terms....
The first thing I'd say is make sure you get an airtight seal around the speaker when mounting. In the front doors, this is pretty easy, in the rear, I dunno what the panel cutout looks like. Foam weatherstip tape, or that clay-like caulking material work great as an auxilary gasket. If the cutout in the rear is big, you may need to fabricate a new baffle for your speaker.
The key here again is to remember that 6.5" speakers work best in a configuration known as "infinite baffle". Think of mounting the speaker on a rigid, air tight wall of infinite size. That means the speaker is loaded in an enclosure of "infinite size" or the compliance of the volume of air behind the speaker is much, much greater than the mechanical compliance of the speaker. So in this case you need the rear of the speaker unobstructed (no small air volume enclosure, thus no foam baffle) AND you need the front of the speaker to be as well sealed off from the rear as possible. Think in those terms and you'll optimize the speaker's response. Not sure how big the air volume behind those rear 6.5s are, but if it is really tight back there, then that could really contribute to the problem.
The final thing to look at is the rigidity of the baffle. If the structure the speaker is mounted to moves, then you will lose bass reponse. Again, a custom fab'd baffle plate can help if this is the case.
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-SJ (former username: shinjohn)
'01 DEP EX, and I'm workin' on it! (slowly)
The first thing I'd say is make sure you get an airtight seal around the speaker when mounting. In the front doors, this is pretty easy, in the rear, I dunno what the panel cutout looks like. Foam weatherstip tape, or that clay-like caulking material work great as an auxilary gasket. If the cutout in the rear is big, you may need to fabricate a new baffle for your speaker.
The key here again is to remember that 6.5" speakers work best in a configuration known as "infinite baffle". Think of mounting the speaker on a rigid, air tight wall of infinite size. That means the speaker is loaded in an enclosure of "infinite size" or the compliance of the volume of air behind the speaker is much, much greater than the mechanical compliance of the speaker. So in this case you need the rear of the speaker unobstructed (no small air volume enclosure, thus no foam baffle) AND you need the front of the speaker to be as well sealed off from the rear as possible. Think in those terms and you'll optimize the speaker's response. Not sure how big the air volume behind those rear 6.5s are, but if it is really tight back there, then that could really contribute to the problem.
The final thing to look at is the rigidity of the baffle. If the structure the speaker is mounted to moves, then you will lose bass reponse. Again, a custom fab'd baffle plate can help if this is the case.
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-SJ (former username: shinjohn)
'01 DEP EX, and I'm workin' on it! (slowly)
I have been experimenting with speakers in my 2002 Ody. I did not like the sound of the factory speakers. The factory speakers have a blue plastic cone, and are rated 4 ohm, 20 watts. They sounded best with the treble and bass controls turned up most of the way to max.
My first experiment was to replace the fronts with Pioneer 1695s. I cut away just enough of the rear cone of the rain shield to allow the speaker to fit. With the 1695 in place, and the tone controls level, the treble and bass were great. The bass was particularly good and reached down to low enough frequencies so that I could even feel instruments like the bass drum. The only shortcoming was that there seemed to be a resonance around 1 -2 kHz which gave a honking sound to the music. I found this annoying on classical music with strings or woodwinds. On speech, and on pop music, the effect was not very noticeable.
My next experiment was to get some Clarion SRX1685's and put those in the front to see if that would fix the honkiness. The Clarions have much smaller magnets than the Pioneers, but bigger than the factory speakers. They seem to be slightly less honky than the Pioneers, bit I still want to do better. They also have a little less bass than the Pioneers, but are still much better than the factory speakers.
I then decided to try the 1695s in the rear. The factory speakers being replaced in the rear look exactly the same as the fronts except that they have paper cones instead of plastic.
With the 1695s in the rear, the bass sound that I had heard in the front was not there.
The cavity behind the speakers is enormous. It is probably 4 to 6 inches deep which gives plenty of clearance. The cavity is open down to floor level so the cavity volume is very large. On the passenger side there are some heating or a/c pipes there, but these are well away from the speaker.
The speaker mounts well to the white plastic panel. I got one of the screws through a speaker mounting hole. The other two screws are outside the speaker frame, and the washers on the screws clamp down the edge of the speaker to the plastic panel. The seal around the speaker is excellent.
The problem is that the white panel itself is not much large than the speaker and does not seal itself to the cavity. Both the gap is irregularly shaped, so there is no obvious way to seal it.
If I could seal the gap, I think the bass would come back, but I haven't thought of a way to do it.
On the fronts, I am guessing that the honking sound is a resonance effect. It may be the echo from the outer door panel. The spacing is just about right to give resonances in this frequency band. At 1000 Hz a half wavelength is about 6 inches. My thought is that I need to damp this resonance by adding some acoustic damping material which will absorb mid band frequencies behind the speaker. I would have to mount it close to the speaker so it would stay dry, and also not interfere with the window. I have not yet figured out what to use or how to mount it.
One other thought I had is that the original rain shield that I have partially cut away masked about half of the rear of the speaker. Could it be that it also had the effect of breaking up the resonance?
REQUEST 1
Could someone who has mounted the SRX1685s without cutting the rain shield listen for this midband honkiness and let me know if it is there? Classical music in the Mozart style shows this defect well.
REQUEST 2
Does someone have any ideas on sealing the rear panel? I did see a post from someone who tried a baffle on 1695s in the rear and said that the baffle made things worse, so that does not seem like the right way to start.
I hope someone can help get me closer to perfection.
[This message has been edited by Cymro (edited 12-06-2001).]
My first experiment was to replace the fronts with Pioneer 1695s. I cut away just enough of the rear cone of the rain shield to allow the speaker to fit. With the 1695 in place, and the tone controls level, the treble and bass were great. The bass was particularly good and reached down to low enough frequencies so that I could even feel instruments like the bass drum. The only shortcoming was that there seemed to be a resonance around 1 -2 kHz which gave a honking sound to the music. I found this annoying on classical music with strings or woodwinds. On speech, and on pop music, the effect was not very noticeable.
My next experiment was to get some Clarion SRX1685's and put those in the front to see if that would fix the honkiness. The Clarions have much smaller magnets than the Pioneers, but bigger than the factory speakers. They seem to be slightly less honky than the Pioneers, bit I still want to do better. They also have a little less bass than the Pioneers, but are still much better than the factory speakers.
I then decided to try the 1695s in the rear. The factory speakers being replaced in the rear look exactly the same as the fronts except that they have paper cones instead of plastic.
With the 1695s in the rear, the bass sound that I had heard in the front was not there.
The cavity behind the speakers is enormous. It is probably 4 to 6 inches deep which gives plenty of clearance. The cavity is open down to floor level so the cavity volume is very large. On the passenger side there are some heating or a/c pipes there, but these are well away from the speaker.
The speaker mounts well to the white plastic panel. I got one of the screws through a speaker mounting hole. The other two screws are outside the speaker frame, and the washers on the screws clamp down the edge of the speaker to the plastic panel. The seal around the speaker is excellent.
The problem is that the white panel itself is not much large than the speaker and does not seal itself to the cavity. Both the gap is irregularly shaped, so there is no obvious way to seal it.
If I could seal the gap, I think the bass would come back, but I haven't thought of a way to do it.
On the fronts, I am guessing that the honking sound is a resonance effect. It may be the echo from the outer door panel. The spacing is just about right to give resonances in this frequency band. At 1000 Hz a half wavelength is about 6 inches. My thought is that I need to damp this resonance by adding some acoustic damping material which will absorb mid band frequencies behind the speaker. I would have to mount it close to the speaker so it would stay dry, and also not interfere with the window. I have not yet figured out what to use or how to mount it.
One other thought I had is that the original rain shield that I have partially cut away masked about half of the rear of the speaker. Could it be that it also had the effect of breaking up the resonance?
REQUEST 1
Could someone who has mounted the SRX1685s without cutting the rain shield listen for this midband honkiness and let me know if it is there? Classical music in the Mozart style shows this defect well.
REQUEST 2
Does someone have any ideas on sealing the rear panel? I did see a post from someone who tried a baffle on 1695s in the rear and said that the baffle made things worse, so that does not seem like the right way to start.
I hope someone can help get me closer to perfection.
[This message has been edited by Cymro (edited 12-06-2001).]
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Yes, I know of what you speak. What orientation do you have the horn turned? To minimize this affect, turn the horn so that its long axis is oriented AWAY from your ears. That may help, some.
It sounds to me like you need something better than the price range you are looking. You sound like you are more discriminating, and I'd recommend you look higher up for better sound.
The clay like caulking material I spoke of; works well, and can be formed by hand. Another (messier, and smellier til it dries) option is using silcone window sealant. I use this stuff in speaker boxes all the time....
I think you speak more of a characteristic sound of the speaker, and the horn's beaming effect at frequencies too low for its flare.
You can try damping, but I doubt it will help much, if at all.... If you wanna try, just pop out the speaker, put some damping material behind it (not worrying about window operation for the time being) and see....
Getting good sound in a car is ALOT harder than getting it at home. I'm still working on it and am still VERY VERY far away from "getting closer to perfection". If you are serious about getting better sound in your Ody, start by giving your self a good chance. Spend some good dough on front speakers. I mean $350+ for a front set. That's the realm I think you need to be in if you can discern the things you are writing and can talk the talk you do.
Best of luck to ya!
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-SJ (former username: shinjohn)
'01 DEP EX, and I'm workin' on it! (slowly)
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135 Posts
I think the doors make better enclosures for the speakers than do the rear side panels.
1) Make sure the speakers are wired in phase with each other.
2) You could try filling the area behind the speakers with "polyester fiberfill."
They sell this stuff in Crutchfield and other places and this should help isolate the
back wave from the front wave of the speaker.
If these waves are not isolated from each other, like they would be in a box or when mounted on the rear deck of a car, they can cancel each other and reduce (or eliminate) your bass output.
Good luck!!
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Nelson
2001 Odyssey LX - Silver
2001 Civic EX Sedan - Silver
1990 Mustang LX Coupe - Titanium
1) Make sure the speakers are wired in phase with each other.
2) You could try filling the area behind the speakers with "polyester fiberfill."
They sell this stuff in Crutchfield and other places and this should help isolate the
back wave from the front wave of the speaker.
If these waves are not isolated from each other, like they would be in a box or when mounted on the rear deck of a car, they can cancel each other and reduce (or eliminate) your bass output.
Good luck!!
------------------
Nelson
2001 Odyssey LX - Silver
2001 Civic EX Sedan - Silver
1990 Mustang LX Coupe - Titanium
Joined
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2,132 Posts
Phase coherency left and right is critical. Front to rear is another story. You may actually get better mid-bass response if you wire rears out of phase relative to fronts. See "Speaker Phasing" thread by Dorhn for his experiments with his 6x9s. Not apples to apples here, but something to consider. You don't know until you try.
I'm a bit skeptical of this solution, but you sure could give it a try if you want. Can't hurt, and may even smooth out the bass response a litte....
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-Shin John
'01 DEP EX, and I'm workin' on it! (slowly)
[This message has been edited by shindog (edited 12-07-2001).]
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1,446 Posts
Cymro is right about the air gap between the white plastic panel the speaker mounts to, and the grey plastic enclosure. This needs to be sealed in order to isolate the front wave from the rear wave. I have not done so, but I think that you could use some strips of "Dynamat," that adhesive-backed rubber stuff, available from Crutchfield.
DAL,
By any chance, have you tried your rear speakers with or without the baffles? I am no expert, and I do not want to upset any experts, but it seems to me that the the rear speakers would sound better with baffles just a few inches longer than the length of the speaker. I would guess that your front speakers needed a little bit of space, as opposed to a large or minimal space, behind the speakers to sound good. What do you think?
Jon M.
By any chance, have you tried your rear speakers with or without the baffles? I am no expert, and I do not want to upset any experts, but it seems to me that the the rear speakers would sound better with baffles just a few inches longer than the length of the speaker. I would guess that your front speakers needed a little bit of space, as opposed to a large or minimal space, behind the speakers to sound good. What do you think?
Jon M.
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2,132 Posts
Some people in this forum have tried the baffles in the rear in the '02s to see if they help with bass response. The consensus was that they made it worse.
In my experience, most 6.5" speakers were designed for optimal performance in large enclosures (infinite baffle). Many small 4" speakers often work better with a baffle or surrounding enclosure because they were meant to be installed in smaller dash cutouts.
This is not to say that there isn't a 6.5" speaker out there that would work well with a baffle. It's just that the 1695 and many other popular 6.5"s that sound good in doors don't work well with a baffle.
When in doubt, give it a shot and see what happens.
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-Shin John
'01 DEP EX, and I'm workin' on it! (slowly)
Yeah, I don't feel too much improvement putting a pair of 1695's in the rear comparing to moving the front 02 speakers to the rear. I tried again during the weekend and decided to keep my front "blue" speakers in the rear and only one pair of 1695's in the front. Honestly, I could barely hear the rear speakers while driving and I doubt how my 10 month old baby would tell any difference.
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The only time I would hear the rear speakers is when I sitting in the back watching DVD or football (yes, I installed a tuner to the RES) while waiting for my wife in a mall parking lot... But, I would prefer most of the sound coming from the front speakers (that would be behind the screen) than coming from the rear while using the RES. Oh, and wife does not allow me to buy more toys for myself...
Sid
[This message has been edited by ody2002 (edited 12-10-2001).]
Sid
[This message has been edited by ody2002 (edited 12-10-2001).]
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I too think this honkyness more a characteristic of the speaker itself than a resonance.
I haven't installed my rear upgrade speakers yet until I find a way to properly seal the cavity. Otherwise, you will get no base improvement.
What I am thinking of is making a custom thin, rigid panel that fits the over the white plastic to properly seal the cavity, then mount the speaker to this panel.
What a PITA!
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Another solution for the rear speakers: Does anyone make a small shallow speaker cabinet for a 6.6 inch speaker that is open in the back? I am thinking about the same size as the OEM grill. You could mount this directly over the hole and it would seal around the edges, and therefore give you a nice big sealed cavity behind the speaker.
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