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<blockquote data-quote="eharri3" data-source="post: 5449004" data-attributes="member: 591579">Are you jsut setting your gain at the head unit&#039;s voltage output rating and leaving it like that?Could be your head unit isn&#039;t making the rated output voltage on the sub RCA pre out. I have the same issue, my MRP-M500 is wired at 4 ohms to my Pioneer Premier 10. I can&#039;t get the right voltage&nbsp; on the dmm from my MRP M500 unless my gain is somewhere around 1-1.5 volts and my head unit is rated for four. I don&#039;t seem to get a linnear rise in sub volume until it&#039;s set right about there.&nbsp; If I try it with the amp at 4 volts the sub doesn&#039;t hit until I&#039;m almost near max volume.It&#039;s been this way with a 2 and 4 volt Alpine head unit, with the 2 volt my gain was around .5 volts. And meanwhile&nbsp; my mid-high amp always ends up almost exactly at the input sensitivity level that matches the head unit voltage rating. After some research I found out some Alpine head units have a history of making less voltage on the sub pre-outs, meaning you&#039;ll be cranking the gain more than you think is right to get the max output and it&#039;ll look like the sub amp isn&#039;t doing rated power. I guess I won&#039;t know for sure what the issue is until/unless I try it with a head unit that is known to make rated output or close to it at the sub pre out. With my gain this high though my sub hits like it should and sounds clean all the way to my max undistorted volume, with no boost. This thing may be underpowered but if Im reading things right it would have to be underpowered by way more than a 3rd to be this much off. I find that hard to believe even with a low end Alpine, maybe if it was Sony Xplod or something. And even with the gain at less than 2 volts and the volume cranked there&#039;s never audible distortion, which I would imagine there would be if the extra power needed to get me the right voltage on the dmm came from a badly clipped signal. When I move the gain knob with the DMM hooked up the output voltage is still rising gradually in this range, no sudden jumps or anything like it goes right from 20 to 40.I have looked high and low for bench tests or reviews and never seen any.</blockquote>

[QUOTE="eharri3, post: 5449004, member: 591579"] Are you jsut setting your gain at the head unit's voltage output rating and leaving it like that? Could be your head unit isn't making the rated output voltage on the sub RCA pre out. I have the same issue, my MRP-M500 is wired at 4 ohms to my Pioneer Premier 10. I can't get the right voltage on the dmm from my MRP M500 unless my gain is somewhere around 1-1.5 volts and my head unit is rated for four. I don't seem to get a linnear rise in sub volume until it's set right about there. If I try it with the amp at 4 volts the sub doesn't hit until I'm almost near max volume. It's been this way with a 2 and 4 volt Alpine head unit, with the 2 volt my gain was around .5 volts. And meanwhile my mid-high amp always ends up almost exactly at the input sensitivity level that matches the head unit voltage rating. After some research I found out some Alpine head units have a history of making less voltage on the sub pre-outs, meaning you'll be cranking the gain more than you think is right to get the max output and it'll look like the sub amp isn't doing rated power. I guess I won't know for sure what the issue is until/unless I try it with a head unit that is known to make rated output or close to it at the sub pre out. With my gain this high though my sub hits like it should and sounds clean all the way to my max undistorted volume, with no boost. This thing may be underpowered but if Im reading things right it would have to be underpowered by way more than a 3rd to be this much off. I find that hard to believe even with a low end Alpine, maybe if it was Sony Xplod or something. And even with the gain at less than 2 volts and the volume cranked there's never audible distortion, which I would imagine there would be if the extra power needed to get me the right voltage on the dmm came from a badly clipped signal. When I move the gain knob with the DMM hooked up the output voltage is still rising gradually in this range, no sudden jumps or anything like it goes right from 20 to 40. I have looked high and low for bench tests or reviews and never seen any. [/QUOTE]

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