Memphis vs Boston Acoutics
08-30-2005, 07:45 PM
#21
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Originally Posted by jwa4378,Aug 30 2005, 04:18 PM
if they sound alright by themselves, chances are that they are aligned correctly. You can test them yourself. If you have a bass test CD, go to the Thump track. See if it kicks in or out. Sounds like a phasing problem to me. Sounds like the rear signal is hitting your head faster than the front signal, so you are kind of hearing the same thing twice, thus creating a sort of veiled sound (your ear thinks its one signal, and tries to process it as such, but the time align is slightly off). Does your head unit have a time delay funcition? If so, you may want that tweaked.
John
John
The Pioneer has an auto time align function. Put the included mic on the driver's headrest, turn on the function, it sends pink noise out all outputs (one at a time I'm sure), then times them to all hit the driver's seat the same time....The rears MAY still be out of phase with the fronts, don't forget. But after Art "pops" them I'll know what's up.
Thank you for your continued replies about this, John!
I'm surprised you're not sick of me talking about this yet....I know my wife is... 
09-04-2005, 09:41 PM
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Hi, everyone! 
I am going to Nsxnext1's shop on Tuesday to check F/R polarity, but I think I cleaned up the sound: I turned off the HPF for the rears (set it to PASS). This made the sound "tighter" and more frequency-coherent, with a little more low end and less harshness (since it stopped comb filtering). I went through 5-6 CDs switching between HPF for the rears ON and OFF, and ON degraded the sound on all CDs.
I thought you should have front and rear HPFs ON when using a sub, but your ears are the final judge, after all...........
More on Tuesday night or Wednesday morn.
Thanks to everyone for your input!
Mike
I am going to Nsxnext1's shop on Tuesday to check F/R polarity, but I think I cleaned up the sound: I turned off the HPF for the rears (set it to PASS). This made the sound "tighter" and more frequency-coherent, with a little more low end and less harshness (since it stopped comb filtering). I went through 5-6 CDs switching between HPF for the rears ON and OFF, and ON degraded the sound on all CDs.
I thought you should have front and rear HPFs ON when using a sub, but your ears are the final judge, after all...........
More on Tuesday night or Wednesday morn.
Thanks to everyone for your input!
Mike
09-05-2005, 11:57 AM
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i knew a guy that had his rear fills rolled off in the higher ranges via a Roland Boss DD3? i beilieve; sounded amazing. rather than just cut the frequency off at a particular area it was more of a gentle roll off from low to a higher frequency before finally cutting altogether. the roland boss is essentially a foot pedal for guitars.
09-05-2005, 12:36 PM
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Originally Posted by formulaofsuccess,Sep 5 2005, 11:57 AM
i knew a guy that had his rear fills rolled off in the higher ranges via a Roland Boss DD3? i beilieve; sounded amazing. rather than just cut the frequency off at a particular area it was more of a gentle roll off from low to a higher frequency before finally cutting altogether. the roland boss is essentially a foot pedal for guitars.
Yeah, when I did the Auto EQ and Time Align in the Pioneer, it rolled off the highs from the rears also...but it made them muddy and I did not like it, so I reset it the way I had it before.
More testing today supports that OFF is the way to go with the rear HPF....in my car at least.
I will still check polarity tomorrow...that MAY have something to do with why the Rear HPF would be so drastic in relation to the Fronts....
Mike
09-06-2005, 06:08 PM
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WOOHOOO!!!! FIXED!!!!!!!!
Nsxnext1's tech checked out the car for me and found two things:
1. The left (driver's) mid-bass driver was out of polarity. So not only was it out with the left tweeter, but also fought against the mid-bass in the passenger door. No wonder it sounded thin
2. The foam "buckets" that the installer used were not cut out, and a little small for the Infinity Kappa Perfect 6.1 mid/bass driver so the speakers were suffocating in the buckets. The tech cut out the foam, just leaving an "umbrella" for water deflection, and you would not believe the improved low frequency response!!! OK, maybe you guys would...
All in all, a happy day for me. Nice to know that after all these years of playing and recording music, my ears can still pick up one out-of-phase driver in a system of 7 total drivers
Thanks again to Nsxnext1, his tech, Alex, and to all my friends here who helped me troubleshoot this and who gave their opinions!!
Nsxnext1's tech checked out the car for me and found two things:
1. The left (driver's) mid-bass driver was out of polarity. So not only was it out with the left tweeter, but also fought against the mid-bass in the passenger door. No wonder it sounded thin
2. The foam "buckets" that the installer used were not cut out, and a little small for the Infinity Kappa Perfect 6.1 mid/bass driver so the speakers were suffocating in the buckets. The tech cut out the foam, just leaving an "umbrella" for water deflection, and you would not believe the improved low frequency response!!! OK, maybe you guys would...
All in all, a happy day for me. Nice to know that after all these years of playing and recording music, my ears can still pick up one out-of-phase driver in a system of 7 total drivers
Thanks again to Nsxnext1, his tech, Alex, and to all my friends here who helped me troubleshoot this and who gave their opinions!!
09-06-2005, 06:10 PM
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One other thing....the system sounds better when both front and rears HPFs are OFF. Any reason to NOT do this?? Just seems a LITTLE thinner when the FRONT HPF is ON, of course, since the low end is rolled off. But if OFF, there does not seem to be any frequency interference with the 8" sub in trunk.
Thanks,
Mike
Thanks,
Mike
09-07-2005, 10:28 AM
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I would think that you should only really put the HPF "on" when you are trying to unload bass from the drivers to the sub. This should (IMO) only be beneficial when listening at insanely loud volumes....the point to which the drivers distort because of the bass frequency.
All in all, with everything fixed, how does the Boston compare to the Memphis? I have been waiting to get a clean review, so I can make an educated buy.
John
All in all, with everything fixed, how does the Boston compare to the Memphis? I have been waiting to get a clean review, so I can make an educated buy.
John