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Discussion Starter #1
So I just want to make sure my thinking is correct for the time alignment on the alpine HD-CDE148BT, it is the same for most of that line of alpine hu. The manual states to measure the distance to the farthest speaker and then subtract the distance to that speaker. I averaged the distance for the tweeter and woofer because I'm using passives. It seems like this is doing it really backwards my initial thinking is that it should calculate it for me when I put in the distances to the various speakers but that is not what the manual says... (the manual, page 67 is the time alignment diagram: https://pdf.crutchfieldonline.com/ImageBank/v20130807074900/Manuals/500/500CDE147B.PDF)

So my measurements:

Speaker setMeasured Distances
front left40
front right53.33333333
subwoofer80

Leads to these settings according to the alpine formula:
Farthest = 80farthest - measured distance
front left40
front right26.66666667
subwoofer0


After explaining the time alignment to my wife she predictably says, "well what about when I'm in the car?" There are presets for that of course :)
 

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So, delay number 30 for front left, delay number 20 for front right, and 0 for sub

Sent from my SM-T530NU using Tapatalk
 

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Do not use the average between the woofer/tweeter - use the distance to the woofer only.
Alpine does not calculate the delay for you, that's why they have the chart in the manual.
This site is helpful too: http://tracerite.com/calc.html
 

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Do not use the average between the woofer/tweeter - use the distance to the woofer only.
Alpine does not calculate the delay for you, that's why they have the chart in the manual.
This site is helpful too: http://tracerite.com/calc.html
OP, follow this advice. Do not average the mid and tweet, use the mid only. And, that website will help you covert the distance into milliseconds.
 

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Discussion Starter #6 (Edited)
Thanks! I actually did a weighted average and gave the tweeter 2/3 of the average and the 1/3 to the woofer thinking that the tweeter's alignment was more important! I applied the settings this morning and the biggest difference was the bass seems to move forward into the sound stage. A lot of the higher frequencies seemed slightly clearer/cleaner but I wonder if I would notice it if I changed it. I would certainly notice the bass. I'll calculate based on the woofer and then use the website to see if its different from the alpine settings.

The alpine chart is fairly close but doesn't match tracerite... This is what I get from tracerite:

T/A Settings In Milliseconds(ms)
Enter these values in your DSP
LT2.34RT1.46
LMR2.34RMR1.46
LMBn/aRMBn/a
SUB:0
1/2 cycle: 0
1/4 cycle: 0

From alpine just using their formula based on just the woofer distances:
By the Alpine Head unit (inches)
Farthest: 80max - distanceCorresponding time value (ms)
front left322.4
front right201.5
subwoofer00


Anybody know what the sub values mean? Is that if you are playing out of phase?
 
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