DSP Curves for OEM Deck
02-15-2005, 06:38 PM
#1
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DSP Curves for OEM Deck
If you ever wondered what the DSP curves look like check this out. I connected an RTA (Real Time Analyzer) directly to the outputs of the OEM deck. The volume is set at 60 and all tone controls are flat. There is a disk with "Pink Noise" (sounds like static) playing. The far left of the display is labeled 25Hz and the far right is 20KHz. Each dot represnts 1/3 octave. There is a line through the center of the screen (horizontal) that represents 0 dB. Dots above this line are boosted and dots below are cut.
This is the electrical output of the deck and not the acoustic response of the system. Ideally, you would want the deck to be electrically flat (like an aftermarket deck would be).
It would be great to be able to keep the OEM deck with it's balanced outputs, high voltage swing, aux input, SAT ready, MP3 ready, great integration with the dash and get rid of the EQ curves.
XB Neutral:
XB Hear:
XB Feel:
XA Neutral:
XA Hear:
XA Feel:
TC Neutral:
TC Hear:
TC Feel:
This is the electrical output of the deck and not the acoustic response of the system. Ideally, you would want the deck to be electrically flat (like an aftermarket deck would be).
It would be great to be able to keep the OEM deck with it's balanced outputs, high voltage swing, aux input, SAT ready, MP3 ready, great integration with the dash and get rid of the EQ curves.
XB Neutral:
XB Hear:
XB Feel:
XA Neutral:
XA Hear:
XA Feel:
TC Neutral:
TC Hear:
TC Feel:
oh you are awesome!! this is exactly what I was curious to know! my ears are good but a spectrum analyzer is awesome!! this is got to be a sticky!!
02-15-2005, 07:12 PM
#4
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cool and very interesting. I am not sure why you would hook it up straight to the deck instead of hooking up the mic and checking the car out that way. even if you can somehow flatten that curve out of the head unit you will still get screwed by the speakers, speaker placement, vehicle acoustics, and system setup. good luck!
02-15-2005, 07:12 PM
#5
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cool and very interesting. I am not sure why you would hook it up straight to the deck instead of hooking up the mic and checking the car out that way. even if you can somehow flatten that curve out of the head unit you will still get screwed by the speakers, speaker placement, vehicle acoustics, and system setup. good luck!
02-15-2005, 07:44 PM
#6
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If I did hook up the mic, I would not be measuring anything useful and it would be a pointless post (some would argue it's pointless already). The eq curves are there to make the cheap speakers sound decent. The problem comes when you add aftermarket speakers that don't have the limitations. The OEM eq curves can actually make the aftermarket system sound worse than before.
With the Scion brand, it's not really a big deal to change the deck, it's not an option on a growing number of cars.
As far as trying to fix the situation, there is someone who is already on it!
http://www.jlaudio.com/press/CleanSweep05.html
With the Scion brand, it's not really a big deal to change the deck, it's not an option on a growing number of cars.
As far as trying to fix the situation, there is someone who is already on it!
http://www.jlaudio.com/press/CleanSweep05.html
02-15-2005, 08:11 PM
#7
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I did not understand what you were trying to do. it is interesting that it makes some aftermarket speakers sound worse. I think I might just wait and and gut the whole sound system at once, instead of adding a piece at a time. Thanks for the info.
02-16-2005, 12:34 AM
#10
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Originally Posted by JLTD
If I did hook up the mic, I would not be measuring anything useful and it would be a pointless post (some would argue it's pointless already). The eq curves are there to make the cheap speakers sound decent. The problem comes when you add aftermarket speakers that don't have the limitations. The OEM eq curves can actually make the aftermarket system sound worse than before.
With the Scion brand, it's not really a big deal to change the deck, it's not an option on a growing number of cars.
As far as trying to fix the situation, there is someone who is already on it!
http://www.jlaudio.com/press/CleanSweep05.html
With the Scion brand, it's not really a big deal to change the deck, it's not an option on a growing number of cars.
As far as trying to fix the situation, there is someone who is already on it!
http://www.jlaudio.com/press/CleanSweep05.html
I checked out jlaudio.. that's a great idea, but luckily scion made it easy for use to swap out the radio (they knew we probably would).. but jl audio has some great toys..
speaking of toys.. where did you get that spectrum analyzer? what do you do for a living? and again i thank you for reading the outputs of the dsp curves, you're exactly right it would be pointless to take the curve off of the speakers since that's not the source equalization!
What speaker output did you get this from? I've noticed a slightly different echo effect from front to back..
02-16-2005, 05:53 AM
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Originally Posted by sciontc_mich
speaking of toys.. where did you get that spectrum analyzer? what do you do for a living? and again i thank you for reading the outputs of the dsp curves, you're exactly right it would be pointless to take the curve off of the speakers since that's not the source equalization!
What speaker output did you get this from? I've noticed a slightly different echo effect from front to back..
02-16-2005, 08:00 PM
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sciontc_mich:
You're absolutely right, we are fortunate that we can easily swap out the radio (for now), but don't kid yourself....The OEMs are trying their best to take your choice away by making it difficult to integrate.
The curves are from the front left channel. I was too lazy to check each channel for all settings (36 pics). You're probably right, the rear channels probably do have a different curve to protect the smaller speaker. The Boston system in the Chrysler 300 actually has a different curves for each channel. If you wanted to make that thing sound good (with aftermarket equipment), you need four 30 band EQ's and an RTA so you can undo all the stuff the factory did (about $1200 in EQ's).
Lonely Raven:
Thanks, but I can't afford all the toys I get to play with!
VtScionGuy:
My purpose was not to pitch anything just to share information. I sent the link when Lightdir asked what was the point if you could not change it. There are a growing number of vehicles out there that changing the radio out is not an option. I have seen CD players in blister packs at Walmart for $99. My problem with the aftermarket radios of today is many are not actually an upgrade and none of them intgrate as well as the OEM. I see that many around here have changed the radio because of video, the Feds will soon be taking that away I assure you! The future of the 12 Volt Industry lies in integration.
You're absolutely right, we are fortunate that we can easily swap out the radio (for now), but don't kid yourself....The OEMs are trying their best to take your choice away by making it difficult to integrate.
The curves are from the front left channel. I was too lazy to check each channel for all settings (36 pics). You're probably right, the rear channels probably do have a different curve to protect the smaller speaker. The Boston system in the Chrysler 300 actually has a different curves for each channel. If you wanted to make that thing sound good (with aftermarket equipment), you need four 30 band EQ's and an RTA so you can undo all the stuff the factory did (about $1200 in EQ's).
Lonely Raven:
Thanks, but I can't afford all the toys I get to play with!
VtScionGuy:
My purpose was not to pitch anything just to share information. I sent the link when Lightdir asked what was the point if you could not change it. There are a growing number of vehicles out there that changing the radio out is not an option. I have seen CD players in blister packs at Walmart for $99. My problem with the aftermarket radios of today is many are not actually an upgrade and none of them intgrate as well as the OEM. I see that many around here have changed the radio because of video, the Feds will soon be taking that away I assure you! The future of the 12 Volt Industry lies in integration.
07-12-2006, 04:50 AM
#18
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If I'm going to keep the stock iPod upgraded head unit, but change out the speakers, add a sub, and get new amps to power the speakers/subs, what would be the best setting for the head unit? I definitely don't want to make the new additions sound bad b/c of a wrong setting on the head unit.
07-12-2006, 07:41 AM
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So in other words it's useless trying to do after market speakers with the stock HU. I like the stock HU and don't want to change it out. What speakers will work with it but still sound right?