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<blockquote data-quote="Ctesibius" data-source="post: 6292518" data-attributes="member: 564131">The problem is that there isn&#039;t a &quot;final&quot; SNR.&nbsp; Signal to noise ratio is exactly what it says; It the ratio of the signal to the noise.&nbsp; Guess what?&nbsp; When you have less signal (1w) then the ratio of signal to noise will be lower (85db) than when you have a large signal (rated power output, 104db).This is one of the reasons you need to know the measurement method used to establish the published SNR between two different amplifiers before you can meaningfully compare them.Good reading on the subject; <a href="http://www.bcae1.com/sig2nois.htm" target="_blank">http://www.bcae1.com/sig2nois.htm</a>One of the most important things to know is that SNR is one of those measurements that doesn&#039;t really mean a whole lot as the differences will be inaudible in when comparing any two amplifiers worth owning.The first indicates that the amplifier is capable of 100w of power output while maintaining less than or equal to 1% THD.The second indicates that the distortion at rated power was .05%Look at the second chart in this picture; <a href="http://www.wjjeeps.com/jl_3004_chart.jpg" target="_blank">http://www.wjjeeps.com/jl_3004_chart.jpg</a> (for example purposes only, as this was simply one of the first I could find quickly)It&#039;s the THD+N vs Power output chart.&nbsp; What happens?&nbsp; Well, as power increases from near zero to 100w, the THD+N is gradually decreasing.&nbsp; Why?&nbsp; Because &quot;N&quot; is &quot;noise&quot;, which is generally a fairly steady figure.&nbsp; Now go back to what we said before about SNR; as power increases the SNR improves, right?&nbsp; Well, this is the reason for the decline in the chart.&nbsp; The level of the signal is increasing, but the THD is very low and &quot;N&quot; is a relatively steady figure.....so as power increase the percentage of THD+N decreases (i.e. improves just like SNR improves as we increase the level of the signal).&nbsp; But then what happens at about 200w?&nbsp; It jumps up fairly quickly!&nbsp; Look on the left hand side, find the 1% line and follow it across.&nbsp; Where does it intersect with the charted line?&nbsp; That would be similiar to the &quot;≤1% THD + N&quot; rating.&nbsp; Then find the .05% and trace it across.&nbsp; That would be similar to the &quot;.05% THD+N&quot; rating.Bi-amping is more a function of the crossover than the amplifier.&nbsp; If the crossover is capable of being bi-amped, then you can do so with basically any 4 channels of amplification be it a 4-channel amp, two 2-channel amps, etc.No.&nbsp; Due to the dynamics of music and other various factors, your speakers will almost never receive 100w from a 100w rated amplifier.&nbsp; But you can also use the gain control, volume knob and other level adjustments to affect the amount of power the speakers will receive.I would go with which ever was cheaper as long as they both offered the features I needed, since they both have pretty close to the same rated power output.</blockquote>

[QUOTE="Ctesibius, post: 6292518, member: 564131"] The problem is that there isn't a "final" SNR. Signal to noise ratio is exactly what it says; It the ratio of the [I]signal[/I] to the noise. Guess what? When you have less [I]signal[/I] (1w) then the ratio of [I]signal to noise[/I] will be lower (85db) than when you have a large [I]signal[/I] (rated power output, 104db). This is one of the reasons you need to know the measurement method used to establish the published SNR between two different amplifiers before you can meaningfully compare them. Good reading on the subject; [URL="http://www.bcae1.com/sig2nois.htm"]http://www.bcae1.com/sig2nois.htm[/URL] One of the most important things to know is that SNR is one of those measurements that doesn't really mean a whole lot as the differences will be inaudible in when comparing any two amplifiers worth owning. The first indicates that the amplifier is capable of 100w of power output while maintaining less than or equal to 1% THD. The second indicates that the distortion at rated power was .05% Look at the second chart in this picture; [URL="http://www.wjjeeps.com/jl_3004_chart.jpg"]http://www.wjjeeps.com/jl_3004_chart.jpg[/URL] (for example purposes only, as this was simply one of the first I could find quickly) It's the THD+N vs Power output chart. What happens? Well, as power increases from near zero to 100w, the THD+N is gradually decreasing. Why? Because "N" is "noise", which is generally a fairly steady figure. Now go back to what we said before about SNR; as power increases the SNR improves, right? Well, this is the reason for the decline in the chart. The level of the signal is increasing, but the THD is very low and "N" is a relatively steady figure.....so as power increase the percentage of THD+N decreases (i.e. improves just like SNR improves as we increase the level of the [I]signal[/I]). But then what happens at about 200w? It jumps up fairly quickly! Look on the left hand side, find the 1% line and follow it across. Where does it intersect with the charted line? That would be similiar to the "≤1% THD + N" rating. Then find the .05% and trace it across. That would be similar to the ".05% THD+N" rating. Bi-amping is more a function of the crossover than the amplifier. If the crossover is capable of being bi-amped, then you can do so with basically any 4 channels of amplification be it a 4-channel amp, two 2-channel amps, etc. No. Due to the dynamics of music and other various factors, your speakers will almost never receive 100w from a 100w rated amplifier. But you can also use the gain control, volume knob and other level adjustments to affect the amount of power the speakers will receive. I would go with which ever was cheaper as long as they both offered the features I needed, since they both have pretty close to the same rated power output. [/QUOTE]

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