Hay guys, I am working on a 1960 four door impala sport Sudan; I am taking it completely apart getting it acid treatment and rebuilding it. This is going to be my daily driver ( it can get 16 or 17 mpg if you leave a 283 in it stock without beefing it up or use a new 5.3 fual injection from a gmc or Chevy truck) and I want my master car system (which is a four way four part based towers with separate rear subs) . I know you guys are home audio but, I need the mathematical and engineering help. I want most of it all figured out, if it means anything I am going to run:
td 1200 nakamichi (cassette deck with remote radio box/ and remote CD player)
Full early 90's generation zapco competition system (all symbilink = RCA with ground plus hot and ground for accessories)
30 band equalizer
4 part crossover
Z100c2 30 watts for tweeters
Z200c2 60 watts for mids
Z300c2 90 watts for mid bass ( or z600c2)
Z600c2 150 watts for sub woofers
Duble that's whole thing for front and back ( starting with front)
I do not know the speakers that needs dessition.
Tweeter
Six to four inch mid
Eight to ten inch midbass
Fifteen inch sub woofer
Now what I need you guys for is phasing I wanna do it all by wire length. The maximum speaker distance range without subs is about 35 inchs give or take 4 inchs by intended ear of speaker, with sub about 80 inches give or take 7 inches. So I need to know how much wire to delay the closest speaker to the farthest, I am having a tough time since it is all engineering math but I figure one of you will know. I know frequency changes phasing offset. So how do I calculate?
Ps no pics but measurements.
Tweeter T
Mid M
Mid bass B
Sub woofer S
Left L
Right R
Front F
Rear P
Left speakers measure with left ear right with right
Rough speaker center measurements
All inches
F R T 35
F R M 43
F R B 48
F L T 61
F L M 68
F L B 70
P L T 58
P L M 55
P L B 56
P R T 42
P R M 46
P R B 51
P S 120
I'm just trying to get this stuff right, I want a very natural acurate system, the car is huge and will have a lot apolstry. The front mids and midbass are the conner in front by the door below the dash, tweeter is roughly 15 inches below eye level in the rear dash and back has mid and bass in the rear deck below the window and tweeters up in the roof. Thank you for reading and replying.
td 1200 nakamichi (cassette deck with remote radio box/ and remote CD player)
Full early 90's generation zapco competition system (all symbilink = RCA with ground plus hot and ground for accessories)
30 band equalizer
4 part crossover
Z100c2 30 watts for tweeters
Z200c2 60 watts for mids
Z300c2 90 watts for mid bass ( or z600c2)
Z600c2 150 watts for sub woofers
Duble that's whole thing for front and back ( starting with front)
I do not know the speakers that needs dessition.
Tweeter
Six to four inch mid
Eight to ten inch midbass
Fifteen inch sub woofer
Now what I need you guys for is phasing I wanna do it all by wire length. The maximum speaker distance range without subs is about 35 inchs give or take 4 inchs by intended ear of speaker, with sub about 80 inches give or take 7 inches. So I need to know how much wire to delay the closest speaker to the farthest, I am having a tough time since it is all engineering math but I figure one of you will know. I know frequency changes phasing offset. So how do I calculate?
Ps no pics but measurements.
Tweeter T
Mid M
Mid bass B
Sub woofer S
Left L
Right R
Front F
Rear P
Left speakers measure with left ear right with right
Rough speaker center measurements
All inches
F R T 35
F R M 43
F R B 48
F L T 61
F L M 68
F L B 70
P L T 58
P L M 55
P L B 56
P R T 42
P R M 46
P R B 51
P S 120
I'm just trying to get this stuff right, I want a very natural acurate system, the car is huge and will have a lot apolstry. The front mids and midbass are the conner in front by the door below the dash, tweeter is roughly 15 inches below eye level in the rear dash and back has mid and bass in the rear deck below the window and tweeters up in the roof. Thank you for reading and replying.
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Hi,
You cannot adjust phasing by the length of the speaker wires in any sense.
Without digital shenanigans you cannot adjust time delay, but you can
with a 4 way digital crossover, but not a 4 way active analogue crossover.
However in the analogue domain the whole set up can be adjusted for
overall group delay (in degrees) with the right x/o points, such that
the overall distances don't matter, but you can't have the tweeters
in the rear, they have to be in the front, with the mid and bass.
Dash mounting the tweeters above the mid and bass is the way to go.
You don't need to replicate drivers front and rear,
T/M/B front and S rear will do the job, and TBH
will sound better in the rear seats than the front.
rgds, sreten.
You cannot adjust phasing by the length of the speaker wires in any sense.
Without digital shenanigans you cannot adjust time delay, but you can
with a 4 way digital crossover, but not a 4 way active analogue crossover.
However in the analogue domain the whole set up can be adjusted for
overall group delay (in degrees) with the right x/o points, such that
the overall distances don't matter, but you can't have the tweeters
in the rear, they have to be in the front, with the mid and bass.
Dash mounting the tweeters above the mid and bass is the way to go.
You don't need to replicate drivers front and rear,
T/M/B front and S rear will do the job, and TBH
will sound better in the rear seats than the front.
rgds, sreten.
An externally hosted image should be here but it was not working when we last tested it.
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Thanks analog is a must... I'm a tape head. There is a mild 5 inch difference within the sets so I would need a a phase adjuster in analog for 4 channels, know any? Any other advice will be welcome.
jplesset
I thought of that, I was asking because i wasn't sure. Resistance equals delay and frequency matters so I thought it maybe doable. I will stick to a phase adjuster.
jplesset
I thought of that, I was asking because i wasn't sure. Resistance equals delay and frequency matters so I thought it maybe doable. I will stick to a phase adjuster.
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I'd suggest just going digital with an off the shelf DSP, I don't get why you are calling it heresy.
Delays aren't that simple to do in the analogue domain, you can't get pure delay as in the digital domain. And to use delays you don't even have to use any DSP filters, you are just buffering up the signal.
I know many people in the car audio industry would disagree but you don't need any delay on the speakers and certainly not by adding 300 kms of wire(!). Carefully adjusting the phase by adjusting the slopes of the crossovers might be helpful thou.
But really the best system in a classic car like that sedan of yours would be a classic one matching the car I think.
But really the best system in a classic car like that sedan of yours would be a classic one matching the car I think.
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