TSX OEM HU and the myth of equalization
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TSX OEM HU and the myth of equalization
In response to some comments made recently by tuan209 and others, and some marketing communication being done by JL Audio and others trying to sell some interfaces, I realized I did not KNOW if the TSX HU OP had equalization. So today I tested the output of the TSX OEM HU for frequency response.
Often, OEM audio systems follow the Bose home audio route - use cheap, crappy drivers, insert an EQ to make them sound as good as is possible with those crappy speakers (and in this case adjusting for the car interior, which is not bad in and of itself) and not worry that cheap crappy speaker drivers deteriorate in their performance quickly, and didn't sound that good in the first place.
So Bose car systems, and many others, do signal processing, or equalization, to the signal, to make it more car-appropriate. Newer VWs, for example, are boosting the bass a lot at lower levels and then cutting that boost and decreasing the bass at higher levels. Keeps the OEM speaks from blowing up, but makes that sub you added in the trunk sould like ass.
Well, there may be EQing in the TSX OEM amp. (Technically, there is some, because technically crossovers are a form of EQing, and the amp has xovers iside, even though there's not much in there in the way of EQ circuitry.)
But the preamp output from the OEM HU to the OEM amp is ruler flat from 20 Hz to 20kHz, and does not change all the way up to the max of 40 on the volume control. The signal seemed to be 1-2 dB down at 25kHz - which is of course due to the filtering of the output signal of any CD player (signals above 22.5k are sharply filtered in some way). It's good both in being flat in performance means that the output with aftermarket amps and speakers can sound good, and that at higher levels no signal compression is performed, so the signal, and the sound, don't change with higher volume settings.
The test was performed with a NT Instruments Acoustilyzer and the Alpine CAN test CD, pink noise track 17.
The OEM HU may not have the expensive DACs or high-voltage line drivers of a competition HU, but in all other respects it should perform JUST like an aftermarket mid-fi HU with RCA outputs.
Have a nice weekend, everyone.
Often, OEM audio systems follow the Bose home audio route - use cheap, crappy drivers, insert an EQ to make them sound as good as is possible with those crappy speakers (and in this case adjusting for the car interior, which is not bad in and of itself) and not worry that cheap crappy speaker drivers deteriorate in their performance quickly, and didn't sound that good in the first place.
So Bose car systems, and many others, do signal processing, or equalization, to the signal, to make it more car-appropriate. Newer VWs, for example, are boosting the bass a lot at lower levels and then cutting that boost and decreasing the bass at higher levels. Keeps the OEM speaks from blowing up, but makes that sub you added in the trunk sould like ass.
Well, there may be EQing in the TSX OEM amp. (Technically, there is some, because technically crossovers are a form of EQing, and the amp has xovers iside, even though there's not much in there in the way of EQ circuitry.)
But the preamp output from the OEM HU to the OEM amp is ruler flat from 20 Hz to 20kHz, and does not change all the way up to the max of 40 on the volume control. The signal seemed to be 1-2 dB down at 25kHz - which is of course due to the filtering of the output signal of any CD player (signals above 22.5k are sharply filtered in some way). It's good both in being flat in performance means that the output with aftermarket amps and speakers can sound good, and that at higher levels no signal compression is performed, so the signal, and the sound, don't change with higher volume settings.
The test was performed with a NT Instruments Acoustilyzer and the Alpine CAN test CD, pink noise track 17.
The OEM HU may not have the expensive DACs or high-voltage line drivers of a competition HU, but in all other respects it should perform JUST like an aftermarket mid-fi HU with RCA outputs.
Have a nice weekend, everyone.
Last edited by elduderino; 02-27-2005 at 01:40 PM.
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Intermediate
![Question](https://acurazine.com/forums/images/icons/icon5.gif)
What amp and how many channels on amp.
With the use of 6x9 Rear keeping all speakers.
What would you recomend?
With the use of 6x9 Rear keeping all speakers.
What would you recomend?
Originally Posted by elduderino
In response to some comments made recently by tuan209 and others, and some marketing communication being done by JL Audio and others trying to sell some interfaces, I realized I did not KNOW if the TSX HU OP had equalization. So today I tested the output of the TSX OEM HU for frequency response.
Often, OEM audio systems follow the Bose home audio route - use cheap, crappy drivers, insert an EQ to make them sound as good as is possible with those crappy speakers (and in this case adjusting for the car interior, which is not bad in and of itself) and not worry that cheap crappy speaker drivers deteriorate in their performance quickly, and didn't sound that good in the first place.
So Bose car systems, and many others, do signal processing, or equalization, to the signal, to make it more car-appropriate. Newer VWs, for example, are boosting the bass a lot at lower levels and then cutting that boost and decreasing the bass at higher levels. Keeps the OEM speaks from blowing up, but makes that sub you added in the trunk sould like ass.
Well, there may be EQing in the TSX OEM amp. (Technically, there is some, because technically crossovers are a form of EQing, and the amp has xovers iside, even though there's not much in there in the way of EQ circuitry.)
But the preamp output from the OEM HU to the OEM amp is ruler flat from 20 Hz to 20kHz, and does not change all the way up to the max of 40 on the volume control. The signal seemed to be 1-2 dB down at 25kHz - which is of course due to the filtering of the output signal of any CD player (signals above 22.5k are sharply filtered in some way). It's good both in being flat in performance means that the output with aftermarket amps and speakers can sound good, and that at higher levels no signal compression is performed, so the signal, and the sound, don't change with higher volume settings.
The test was performed with a NT Instruments Acoustilyzer and the Alpine CAN test CD, pink noise track 17.
The OEM HU may not have the expensive DACs or high-voltage line drivers of a competition HU, but in all other respects it should perform JUST like an aftermarket mid-fi HU with RCA outputs.
Have a nice weekend, everyone.
Often, OEM audio systems follow the Bose home audio route - use cheap, crappy drivers, insert an EQ to make them sound as good as is possible with those crappy speakers (and in this case adjusting for the car interior, which is not bad in and of itself) and not worry that cheap crappy speaker drivers deteriorate in their performance quickly, and didn't sound that good in the first place.
So Bose car systems, and many others, do signal processing, or equalization, to the signal, to make it more car-appropriate. Newer VWs, for example, are boosting the bass a lot at lower levels and then cutting that boost and decreasing the bass at higher levels. Keeps the OEM speaks from blowing up, but makes that sub you added in the trunk sould like ass.
Well, there may be EQing in the TSX OEM amp. (Technically, there is some, because technically crossovers are a form of EQing, and the amp has xovers iside, even though there's not much in there in the way of EQ circuitry.)
But the preamp output from the OEM HU to the OEM amp is ruler flat from 20 Hz to 20kHz, and does not change all the way up to the max of 40 on the volume control. The signal seemed to be 1-2 dB down at 25kHz - which is of course due to the filtering of the output signal of any CD player (signals above 22.5k are sharply filtered in some way). It's good both in being flat in performance means that the output with aftermarket amps and speakers can sound good, and that at higher levels no signal compression is performed, so the signal, and the sound, don't change with higher volume settings.
The test was performed with a NT Instruments Acoustilyzer and the Alpine CAN test CD, pink noise track 17.
The OEM HU may not have the expensive DACs or high-voltage line drivers of a competition HU, but in all other respects it should perform JUST like an aftermarket mid-fi HU with RCA outputs.
Have a nice weekend, everyone.
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