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<blockquote data-quote="XTRProBoy" data-source="post: 2448706" data-attributes="member: 571009">^I said something similar in the other thread (the sticky on how to set your gain).I don&#039;t get the calculation of the &quot;target voltage&quot; at all, particularly since you&#039;re measuring it with no load.&nbsp; Doesn&#039;t sense any make.If my amp puts out a rated 450W RMS at 4-ohms and 1200W RMS at 1-ohm, that would mean if I were running it at 4-ohms I&#039;d look for a target no-load voltage of 42.42V AC.&nbsp; If I were running it at 1-ohm I&#039;d look for a target no-load voltage of 34.64V AC???This doesn&#039;t sense any make at all if you ask me.&nbsp; Input stage gain setting is supposed to match the amplifier for the input signal and nothing else.&nbsp; How does this have anything to do with the load impedance you&#039;re driving (particularly when you&#039;re supposedly measuring the voltage on the speaker terminals of the amp with no load attached)?You&#039;re telling me that if I drive my amp into 4-ohms instead of 1-ohm it magically becomes less sensitive on it&#039;s input stage requiring me to set the gain &quot;higher&quot;???&nbsp; Again, how is this justified/explained?&nbsp; The RCA level from the HU did not change (same test tone, same HU volume level), the amp did not change (it&#039;s the same amp, the same gain knob, no load attached, etc.), so why if you plan on running the amp into a higher impedance (in this case) would you set the gain higher?&nbsp; That has nothing to do with matching the RCA level in that case, as you&#039;re arbitrarily setting the input stage sensitivity so the output terminals of the amp read some strangely calculated figure with no load attached.Maybe I&#039;m just not understanding something here, but just from what I can understand the whole thing seems like nonsense to me.&nbsp; :shrug:Another note:&nbsp; The only way that target voltage would stay the same for all impedances of an amp is if the amp were completely unregulated on the output side meaning it would always double power into half impedance/halve power into double impedance.&nbsp; Some amps are like this, however many amps are not.&nbsp; (E.g. Calculating this target voltage would have netted the same value at any impedance on my old Orion XTRPRO 1000, but the same cannot be said in the case of my HCCA D2400.)Still setting my amp like this either way (either 34.64V or 42.42V) ended up in the sub sounding ridiculously underpowered with music content.&nbsp; Perhaps that&#039;s the point of using the lower test tones/setting gain &quot;overlap&quot; but that still doesn&#039;t account for the strange voltage calculations which don&#039;t seem to make sense at all given that you&#039;re trying to set the amp for the RCA level.</blockquote>

[QUOTE="XTRProBoy, post: 2448706, member: 571009"] ^I said something similar in the other thread (the sticky on how to set your gain). I don't get the calculation of the "target voltage" at all, particularly since you're measuring it with no load. Doesn't sense any make. If my amp puts out a rated 450W RMS at 4-ohms and 1200W RMS at 1-ohm, that would mean if I were running it at 4-ohms I'd look for a target no-load voltage of 42.42V AC. If I were running it at 1-ohm I'd look for a target no-load voltage of 34.64V AC??? This doesn't sense any make at all if you ask me. Input stage gain setting is supposed to match the amplifier for the input signal and nothing else. How does this have anything to do with the load impedance you're driving (particularly when you're supposedly measuring the voltage on the speaker terminals of the amp with no load attached)? You're telling me that if I drive my amp into 4-ohms instead of 1-ohm it [I]magically[/I] becomes less sensitive on it's [B]input stage[/B] requiring me to set the gain "higher"??? Again, how is this justified/explained? The RCA level from the HU did not change (same test tone, same HU volume level), the amp did not change (it's the same amp, the same gain knob, no load attached, etc.), so why if you plan on running the amp into a higher impedance (in this case) would you set the gain higher? [B]That has nothing to do with matching the RCA level[/B] in that case, as you're arbitrarily setting the input stage sensitivity so the output terminals of the amp read some strangely calculated figure with no load attached. Maybe I'm just not understanding something here, but just from what I can understand the whole thing seems like nonsense to me. :shrug: Another note: The only way that target voltage would stay the same for all impedances of an amp is if the amp were completely unregulated on the output side meaning it would [I]always[/I] double power into half impedance/halve power into double impedance. Some amps are like this, however many amps are not. (E.g. Calculating this target voltage would have netted the same value at any impedance on my old Orion XTRPRO 1000, but the same [I]cannot[/I] be said in the case of my HCCA D2400.) Still setting my amp like this either way (either 34.64V or 42.42V) ended up in the sub sounding ridiculously underpowered with music content. Perhaps that's the point of using the lower test tones/setting gain "overlap" but that still doesn't account for the strange voltage calculations which don't seem to make sense at all given that you're trying to set the amp for the RCA level. [/QUOTE]

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