Second Article Published
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From: Boise ID
Second Article Published
http://www.hometheaterhifi.com
We evaluated the stock system... pretty sorry THD and freq respose.
Brian
Car Audio Editor
We evaluated the stock system... pretty sorry THD and freq respose.
Brian
Car Audio Editor
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From: Taylor TX
NCM Sinkhole Donor
Re: Second Article Published (brianw21)
Great article Brian. Are you open to technical critique?
I believe this is slightly inaccurate. Only the 8" is driven by the amp in the door, which also provides the filter for the 8". The 3" is filtered by the Bose processor, but is amplified by the HU internal amp (same for the rear speakers).
The HU sends full-range to the processor, the processor does filtering and other magic "Bose" processing, then the processed signal is sent back to the HU for amplification to the speakers. So the HU has pre-out's and pre-in's for the front 3's and the rear 5.25's. It also has speaker-outs for the front and rears.
I'm assuming the 18W you measured was at the 3" - not the 8". The 8" should have been something like 50W RMS.
But it still sucks, I agree :jester
Each amp powers a 3" and 8" driver, in each door. We were able to get about 18 watts out of one using a voltmeter
The HU sends full-range to the processor, the processor does filtering and other magic "Bose" processing, then the processed signal is sent back to the HU for amplification to the speakers. So the HU has pre-out's and pre-in's for the front 3's and the rear 5.25's. It also has speaker-outs for the front and rears.
I'm assuming the 18W you measured was at the 3" - not the 8". The 8" should have been something like 50W RMS.
But it still sucks, I agree :jester
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From: Boise ID
Re: Second Article Published (lotzahp)
Thanks, the article was edited to be more specific. I actually measure 38 watts using a 25hz test tone, but the THD was off the charts >4%. The 18watt measurement was confined by the best THD mesurement.
We haven't yet agreed to the max power rating measurements for class D amplifiers. In my opinion up to 2% THD is acceptable, and not very noticeable below 100hz. Some of my colegues disagree :)
Brian
We haven't yet agreed to the max power rating measurements for class D amplifiers. In my opinion up to 2% THD is acceptable, and not very noticeable below 100hz. Some of my colegues disagree :)
Brian
