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<blockquote data-quote="Silas Pradetto" data-source="post: 24827" data-attributes="member: 34">Re: Help me understand system limiting- setting itYou are correct- the amplifier&#039;s maximum output voltage (and associated wattage into a load) doesn&#039;t matter. Limiting the amplifier&#039;s input voltage limits its maximum output voltage (and again, the watts), which is your goal. You do not need all amp gains to be the same, although it does help with calculations since one more variable is removed and confusion is reduced. When using carefully set limiters, it is best to calculate them with the amp gain turned all the way up, so no one turns the knob up later, effectively rendering your limiter useless.There is only one problem: if you do wrap your head around the calculations involved with getting your DSP settings to equate to amplifier outputs, how do you know what actual limiter setting is best? You can&#039;t brickwall a speaker, it sounds really bad. So where do you engage a soft &#039;RMS&#039; limiter, where do you engage a peak limiter, and what about a thermal limiter? Where does the speaker actually fail, such that you can prevent failure by preventing that condition? You don&#039;t want to limit too early, reducing maximum output, but limiting too late is essentially the same as no limiter.I have a tip: think of amplifier output as voltage, because that&#039;s what it is. If you have 1 volt going into the amplifier and it has a 40x gain (32dB), then 40 volts are coming out, which is 200 watts at 8 ohms. Formula for gain:Gain (dB) = 20*log(voltage 2/voltage1)Forumla for watts from voltage:P (watts) = Voltage^2/R (nominal impedance usually)I hope this helps.Edit: and one more thing. You have to check what scale your DSP is using for output voltage. The common one is dBu, but some use dBv I think. One is referenced to 1 volt, the other to .775 volts, at some impedance, IIRC. You should research and see exactly what your DSP is using, because you have to turn your &#039;amp input voltage&#039; which is your DSP output voltage into dBu again for entering into the DSP.</blockquote>

[QUOTE="Silas Pradetto, post: 24827, member: 34"] Re: Help me understand system limiting- setting it You are correct- the amplifier's maximum output voltage (and associated wattage into a load) doesn't matter. Limiting the amplifier's input voltage limits its maximum output voltage (and again, the watts), which is your goal. You do not need all amp gains to be the same, although it does help with calculations since one more variable is removed and confusion is reduced. When using carefully set limiters, it is best to calculate them with the amp gain turned all the way up, so no one turns the knob up later, effectively rendering your limiter useless. There is only one problem: if you do wrap your head around the calculations involved with getting your DSP settings to equate to amplifier outputs, how do you know what actual limiter setting is best? You can't brickwall a speaker, it sounds really bad. So where do you engage a soft 'RMS' limiter, where do you engage a peak limiter, and what about a thermal limiter? Where does the speaker actually fail, such that you can prevent failure by preventing that condition? You don't want to limit too early, reducing maximum output, but limiting too late is essentially the same as no limiter. I have a tip: think of amplifier output as voltage, because that's what it is. If you have 1 volt going into the amplifier and it has a 40x gain (32dB), then 40 volts are coming out, which is 200 watts at 8 ohms. Formula for gain: Gain (dB) = 20*log(voltage 2/voltage1) Forumla for watts from voltage: P (watts) = Voltage^2/R (nominal impedance usually) I hope this helps. Edit: and one more thing. You have to check what scale your DSP is using for output voltage. The common one is dBu, but some use dBv I think. One is referenced to 1 volt, the other to .775 volts, at some impedance, IIRC. You should research and see exactly what your DSP is using, because you have to turn your 'amp input voltage' which is your DSP output voltage into dBu again for entering into the DSP. [/QUOTE]

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