![]() So I am thinking that if I put a pair of simple 100mV full scale analog DC meters across the OP, I can more or less, extrapolate/interpret a 50 to 100mv needle deflection as showing the presence of a clipped AC wave form. ![]() As soon as I started to clip the amp, boom, the meter interpreted the "minor" clip and read/interpreted it as a DC component and measured a significant increase of 20X tp 40X the prior full clean power level of 1-3mV. All the way up to, but prior to the 93.5 V threshold, there was obviously nothing appreciable for the meter to read except the presence of 1 to 3mV offset voltage, even at full power (93.4 V). The clipping detector shown here relies on one factor - how close to the supply voltage is the amplifiers output signal at any instant in time. Nominal, full-scale line input of 200 mV rms lights two of the green LEDs. Ii) Secondly on the clipping, I was playing around on the bench with my Marantz 2325, after adjusting the DC offset and Bias, I thought I would start to clip the amp through dummy loads and see how a DC meter would "see/interpret" the clipped wave form. This value is convenient for this application, which uses three green LEDs, two yellow LEDs, and one red LED to show the relative peak levels of the stereo channels. it is a temp measure until I get a larger one off the bench. The amp I was using is not that powerful so Im not suprised. ![]() I noticed on one pair of speaker that when I hit the peaks, the tweeters would drop put, these are a medium sized pair of Polk Audio 3 way's, anyway they cut out and came back on, is it safe to assume that there is some kind of protection built into the internal crossover? is this common in certain brands? Othewise I cant figure out why they would shut down and come right back again. I) -I was testing my rig out using some test songs with some dynamic range content. maybe a comment or thought on them both.(all around the clipped signal subject). I did notice a couple of things that puzzled me in the last couple of days of tweaking and testing. This circuit was intended to be used as a separate, portable unit, to signal by means of a LED when the output wave form of a particular audio stage is. So it doesn't detect a square wave but just compares output to rail. But thanks all for the rather firm straightening up, I feel a bit taller now. Isn't this just a peak voltage detector circuit and not an actual clipping detector Based on the circuit linked the circuit requires amplifier rail voltage and compares the signal to that, when they are equal the LED is powered. I'm sorry for my "loose" use of terms, re "DC", like I said, I only started my bench back up after 30 yrs and I'm not so sure how good I was in the first place at least compared to some of the professional level people here. I grabbed a breadboard yesterday, so I think maybe except, the quick fix thought below ii) the only way is to make the circuit then calibrate and verify it with the scope. Ok, I will stop calling DC, I see where most say just listen for it, well I do, but the problem is if I am driving 2 or 3 stereo amps simultaneously, it is impossible to discern which one of them is clipping.
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