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<blockquote data-quote="helotaxi" data-source="post: 2556523" data-attributes="member: 550915">OK Yoda, to you explain it I will.&nbsp; Your amp is not in a perfect lossless world.&nbsp; It doesn&#039;t double its power output each time you half the impedance.&nbsp; It&#039;s not that the amp is less sensitive at the lower impedance, its just that the rail voltage droops underthe high cerrnt load and it take less imput signal to clip the output because of the lower rail. This actaully answers your question from above and is exactly the issue.&nbsp; This whole tutorial is the basic way to do it if you don&#039;t have access to an oscilloscope and you have an amp whose rated output you can trust as legit.Setting the input gain to give you the correct output voltage is exactly what you are trying to do by setting the gain in the first place.&nbsp; If the output doesn&#039;t double each time you half the impedance, then you have to set it with a lower voltage in mind to account for power rail droop to avoid clipping.&nbsp; BTW, even on the older Orion and PPI amps that advertised 2x the powr into 1/2 the load, they didn&#039;t double their power into the lower load.&nbsp; If you were to set them into the higher load for max unclipped power instead of merely rated power you would find that they were comfortably underrated into the higher impedance in order to make their rating into the lower one.&nbsp; With the new amps there is no motivation to underrate the 4 ohm output os they rate it at what it will do and then apply reality to the lower imp. loads.Most people that set their gains with the 0dB tones are quite disappointed because music just doesn&#039;t get to that output level.&nbsp; You are shorting yourself out of 50-75% of the potential of the amp.&nbsp; Use a -3 or -6dB tone and you will quickly find a lot more output.</blockquote>

[QUOTE="helotaxi, post: 2556523, member: 550915"] OK Yoda, to you explain it I will. Your amp is not in a perfect lossless world. It doesn't double its power output each time you half the impedance. It's not that the amp is less sensitive at the lower impedance, its just that the rail voltage droops underthe high cerrnt load and it take less imput signal to clip the output because of the lower rail. This actaully answers your question from above and is exactly the issue. This whole tutorial is the basic way to do it if you don't have access to an oscilloscope and you have an amp whose rated output you can trust as legit. Setting the input gain to give you the correct output voltage is exactly what you are trying to do by setting the gain in the first place. If the output doesn't double each time you half the impedance, then you have to set it with a lower voltage in mind to account for power rail droop to avoid clipping. BTW, even on the older Orion and PPI amps that advertised 2x the powr into 1/2 the load, they didn't double their power into the lower load. If you were to set them into the higher load for max unclipped power instead of merely rated power you would find that they were comfortably underrated into the higher impedance in order to make their rating into the lower one. With the new amps there is no motivation to underrate the 4 ohm output os they rate it at what it will do and then apply reality to the lower imp. loads. Most people that set their gains with the 0dB tones are quite disappointed because music just doesn't get to that output level. You are shorting yourself out of 50-75% of the potential of the amp. Use a -3 or -6dB tone and you will quickly find a lot more output. [/QUOTE]

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