Working in live audio production, you might have the occasion of working on equipment not set up to handle louder volumes than your gig requires. Speakers are being pushed beyond their limits.I’ve seen this when a bassist uses a SansAmp on stage and is boosting their signal so much that it overloads the input. An instrument sends too hot of a signal into the system.For example, the microphone can’t handle the volume level which it’s detecting and thus distorts the sound that it’s sending into the sound system. A microphone or sound source, like a computer, is overloaded with sound.Reasons for distortionĪudio distortion can occur for a number of reasons. It will amplify the signal only up to its maximum capacity, at which point the signal cuts or clips at the maximum capacity of the amplifier. Clipping, in this case, occurs when an amplifier is pushed to create a signal with more power than its power supply can produce. It’s one thing to over-drive speakers, it’s another to over-drive an amp. This can be seen on the channel level, mixer level, and even the amplifier level. For the needs of this article, I’ll leave it at that. Clipping occurs when an audio component can’t provide enough power supply voltage to cleanly handle the signal. Typically, clipping is the reason for distortion as distortion is merely the audible detection of clipping. Another way to look at it is the loss of clarity is distortion, the addition of interference is noise. If you run a power cable next to an unbalanced cable, you’ll hear noise (interference) in the signal. Think of it like this, if you scream into a microphone and the mic can’t handle the loud volume, then the audio signal will be distorted. Noise is an external (random) signal added to the original signal.Distortion is heard as the result of a change of the original signal to something else.Noise versus distortionĪn easy mistake to make is hearing noise in the system and assuming it’s distortion. For some reason, the sound coming out of the system has been negatively altered and we need to fix it. We usually identify it when we say something like, “that doesn’t sound right.” And we usually are right in that assessment. It can also be the result of a corruption of the signal at the source. What is distortion?ĭistortion is the sound heard where there is an unexpected change of the original signal to something else. And that last one is what I’m hitting today. A sound tech sees distortion as a bad sound reflecting a problem in the audio system. A guitarist sees distortion as an effect for applying to their guitar’s sound. For others, they picture a distorted image. For some, they immediately think of “distorting words or phrases” wherein someone takes what you have said and twists it into something else. →Should steps #1 and #2 'Pass' but Step #3 'Fail' your problem almost certainly an open filter inductor (L506)The word distortion has different meanings depending on who you ask.

In which case 500V is an anticipatable/acceptable unloaded EMF - That said, if the amplifier indeed employs solid state diodes (there seems to be some ambiguity on this point?) good practice will employ filter caps specified at maximum working EMFs ≥ 550V. →Should steps #1 and #2 'Pass' but Step #3 'Fail' your problem is almost certainly an open filter inductor (L506) →'Passage' of step #1 coincident with 'failure' of step #2 implicates the 'B+ switch'

Please measure the following (relative to ground) then report your findings here:ġ) The (DC) EMF apparent at the (common) rectifier cathode point.Ģ) The (DC) EMF at the 'load side' of the 'B+ switch'.ģ) The (DC) EMF at each of PSU output points A,B,C,D →Low Secondary output may owe to an overload condition - in such case please disconnect the rectifiers then re-measure the secondary EMF. →Correct secondary EMF coincident with low rectifier output 'indicts' the rectifiers. the switch intervening the rectifier cathodes and the filter chain) closed and making good contact? Are you seeing appropriate (AC) EMF on the secondary? ( Warning! - Please be mindful of your indicator's maximum limits in contemplation of such measurement!) Click to expand.In which case 500V is an anticipatable/acceptable unloaded EMF - That said, if the amplifier indeed employs solid state diodes (there seems to be some ambiguity on this point?) good practice will employ filter caps specified at maximum working EMFs ≥ 550V.īut I understand your immediate problem is very low/no B+?

No sound audio overload