Alpine (9833) Time Correction in the S2000
Thread Starter
Registered User
Joined: Oct 2000
Posts: 718
Likes: 0
From: SF Bay Area
Alpine (9833) Time Correction in the S2000
Time Correction in Alpine Head Units creates defined delays in specific audio channels so that sound from all speakers reaches the listener's ears at the same instant.
I have made some initial measurements and calculations for Time Correction in the S2000. Please feel free to post your own settings for comparison or so they may serve as a starting point for others who have an install similar to yours (Please post your speaker configuration).
I have the Alpine 9833, but this should work for most people who:
A) have speakers in these common locations, and
b) have an Alpine HU with Time Correction capability
S2000: USDM Left hand drive. All measurements to driver's head. (I am about 6' tall and drive with the seat pretty close to the back--maybe a couple of notches forward from the farthest back position)
Front Speakers: Components with woofers in stock door location and tweeters just in front of the door handle/door lock (distance to listener is the same for tweeter and woofer).
Rear Speakers: Components in rear panels ala Lucid
Subwoofer: None yet.
Anyway, I sat in the drivers seat with a tape measure and got the following measurements for each of the speaker distances (to the closest ear).
Front L = 85 cm
Front R = 122 cm
Rear L = 32 cm
Rear R = 75 cm
Sub L = N/A
Sub R = N/A
The manual says to calculate the time correction 'T' for a speaker 'S',
T = ((distance to farthest speaker - distance to S) / 343) * 1000.
In my case, the most distant speaker is the Front Right. Depending on your install, your farthest speaker may be the same, or it may be a subwoofer in the footwell or trunk.
***********************
Using this calculation I got the time correction for each speaker as follows:
Front L = 0.37 m = 1.1 ms correction
Front R = 0 = No correction (this is the farthest speaker)
Rear L = 0.90 m = 2.6 ms correction
Rear R = 0.47 m = 1.4 ms correction
***********************
Bass Focus:
As far as I can tell Bass Focus is just a way to further change speaker delays in pairs (BEYOND what you have set in Time Correction Mode). The manual doesn't make a lot of sense but if I understand this correctly, one application would be to add a delay to the rear speakers (an echo effect). For this you would just select Bass Focus mode, hit "Band" until the rear speakers are highlighted, then rotate the knob to add a few more ms delay to what is already there.
I haven't messed with Bass Focus yet. I can't even figure out why they call it Bass Focus. All I know is that my HU kicks A$$ over HU's that don't have Bass Focus...
Oh yeah, whatever you do, DO NOT set a negative value for time delay. This may cause the sound to get to your ear before it leaves the speaker, thereby causing a ripple in the space-time continuum and reducing engine torque...
I have made some initial measurements and calculations for Time Correction in the S2000. Please feel free to post your own settings for comparison or so they may serve as a starting point for others who have an install similar to yours (Please post your speaker configuration).
I have the Alpine 9833, but this should work for most people who:
A) have speakers in these common locations, and
b) have an Alpine HU with Time Correction capability
S2000: USDM Left hand drive. All measurements to driver's head. (I am about 6' tall and drive with the seat pretty close to the back--maybe a couple of notches forward from the farthest back position)
Front Speakers: Components with woofers in stock door location and tweeters just in front of the door handle/door lock (distance to listener is the same for tweeter and woofer).
Rear Speakers: Components in rear panels ala Lucid
Subwoofer: None yet.
Anyway, I sat in the drivers seat with a tape measure and got the following measurements for each of the speaker distances (to the closest ear).
Front L = 85 cm
Front R = 122 cm
Rear L = 32 cm
Rear R = 75 cm
Sub L = N/A
Sub R = N/A
The manual says to calculate the time correction 'T' for a speaker 'S',
T = ((distance to farthest speaker - distance to S) / 343) * 1000.
In my case, the most distant speaker is the Front Right. Depending on your install, your farthest speaker may be the same, or it may be a subwoofer in the footwell or trunk.
***********************
Using this calculation I got the time correction for each speaker as follows:
Front L = 0.37 m = 1.1 ms correction
Front R = 0 = No correction (this is the farthest speaker)
Rear L = 0.90 m = 2.6 ms correction
Rear R = 0.47 m = 1.4 ms correction
***********************
Bass Focus:
As far as I can tell Bass Focus is just a way to further change speaker delays in pairs (BEYOND what you have set in Time Correction Mode). The manual doesn't make a lot of sense but if I understand this correctly, one application would be to add a delay to the rear speakers (an echo effect). For this you would just select Bass Focus mode, hit "Band" until the rear speakers are highlighted, then rotate the knob to add a few more ms delay to what is already there.
I haven't messed with Bass Focus yet. I can't even figure out why they call it Bass Focus. All I know is that my HU kicks A$$ over HU's that don't have Bass Focus...
Oh yeah, whatever you do, DO NOT set a negative value for time delay. This may cause the sound to get to your ear before it leaves the speaker, thereby causing a ripple in the space-time continuum and reducing engine torque...
but those look very close.
Registered User
Joined: Oct 2002
Posts: 7,584
Likes: 1
From: Baton Rouge, LA
[QUOTE]Originally posted by LATEOTT
Time Correction in Alpine Head Units creates defined delays in specific audio channels so that sound from all speakers reaches the listener's ears at the same instant.
I have made some initial measurements and calculations for Time Correction in the S2000.
Time Correction in Alpine Head Units creates defined delays in specific audio channels so that sound from all speakers reaches the listener's ears at the same instant.
I have made some initial measurements and calculations for Time Correction in the S2000.
Registered User
Joined: Jan 2004
Posts: 13,826
Likes: 0
From: New Slowmyrna Beach
IMO this is FAQ worthy. Many people will want to know this. I've bookmarked it.
now we need S-pod calcs.
still working on my install. waiting for my sub. It's a doosey.
Thanks Late!
now we need S-pod calcs.
still working on my install. waiting for my sub. It's a doosey.
Thanks Late!
Thread Starter
Registered User
Joined: Oct 2000
Posts: 718
Likes: 0
From: SF Bay Area
Thanks guys!
Hopefully we can get darkknight's and a couple of other measurements to confirm mine.
I was pleasantly surprised at the improvement time correction made. It's cool how you can hear the soundstage shift as you make the corrections.
One thing I might add is that it is likely you will want to reset your L/R balance. We naturally use balance (louder volume) to center the sound stage when sitting off-center, but with time correction I found I don't need as much balance shift.
Hopefully we can get darkknight's and a couple of other measurements to confirm mine.
I was pleasantly surprised at the improvement time correction made. It's cool how you can hear the soundstage shift as you make the corrections.
One thing I might add is that it is likely you will want to reset your L/R balance. We naturally use balance (louder volume) to center the sound stage when sitting off-center, but with time correction I found I don't need as much balance shift.
