mikes2017gt
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I know this is a longshot, but possibly someone might know. I'm trying to determine the maximum clean output setting (before distortion) of the 400A head unit (I have the 9-speaker shaker system.)
I have a SMD DD-1 distortion detector, and tried to use it, but it didn't show any input. Strange. Well, after reading the manual again, I saw that it's trigger voltage is 1.25v. BTW, all HU equalization is off and variable line output is working (Forscan tweaks). Additionally, the HU EQ was set flat, i was faded to the front with the balance all the way to the left front speaker (black plug), which is where I was taking the measurements.
With a Fluke DMM, I measured the HU's max output (at 30 volume setting) to be .83 volts with a 1KHz/0db signal and about the same with a 40Hz/0db signal. What a crappy HU output! Nowhere near the 1.25v the DD-1 needs to see. And here I am.
The generally-accepted rule of thumb for HUs is 75% volume is generally where clipping starts. That would be 22/23 on the HU. BTW, a volume setting of 22 doesn't even give you half a volt....45-something. :( But I'd like a more definitive answer than "22 might be it."
So if you've maybe scoped your HU's outputs or otherwise know what volume setting the 400A HU distorts at, please post it.
I have a SMD DD-1 distortion detector, and tried to use it, but it didn't show any input. Strange. Well, after reading the manual again, I saw that it's trigger voltage is 1.25v. BTW, all HU equalization is off and variable line output is working (Forscan tweaks). Additionally, the HU EQ was set flat, i was faded to the front with the balance all the way to the left front speaker (black plug), which is where I was taking the measurements.
With a Fluke DMM, I measured the HU's max output (at 30 volume setting) to be .83 volts with a 1KHz/0db signal and about the same with a 40Hz/0db signal. What a crappy HU output! Nowhere near the 1.25v the DD-1 needs to see. And here I am.
The generally-accepted rule of thumb for HUs is 75% volume is generally where clipping starts. That would be 22/23 on the HU. BTW, a volume setting of 22 doesn't even give you half a volt....45-something. :( But I'd like a more definitive answer than "22 might be it."
So if you've maybe scoped your HU's outputs or otherwise know what volume setting the 400A HU distorts at, please post it.
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