[Don Pearce[_3_]]

On Sat, 19 Nov 2011 18:05:11 -0600, "
wrote:

On Sat, 19 Nov 2011 18:23:36 GMT, (Don Pearce) wrote:

On Sat, 19 Nov 2011 12:17:35 -0600, "
wrote:

On Sat, 19 Nov 2011 10:16:43 GMT, (Don Pearce) wrote:

On Sat, 19 Nov 2011 20:22:43 +1100, "Trevor" wrote:


"Don Pearce" wrote in message
...
On Fri, 18 Nov 2011 13:51:37 -0800 (PST), RichD
wrote:

What's the difference between reverb, echo, and feedback?

Echo is a single reflection of a sound - the kind you hear when you
shout "Hello" near a cliff.

Multiple reflections are also common in such instances.


No they are not. One cliff, one echo. No choice.

Two walls of said cliff; multiple echoes. If you're on the edge of the cliff
with no opposing wall there will be zero echo.

Since when does one cliff have two walls? The cliff IS the wall.

Zero intelligence.

Feedback is a situation you only get when you have an amplifier and a
speaker. The sound arriving from the speaker is a little louder than
the one that originally hit the microphone, so that comes out of the
speaker a little louder still. This loop will build until the system
howls.

That would be *acoustic feedback* only, There are MANY other types of
course.

In the context of the question it would simply be confusing to discuss
- or even mention - other kinds.

You cure it by turning down the amplifier so the sound from the
speaker is always a little softer than the original when it hits the
microphone.

Or any other method that reduces the loop gain at the feedback frequency,
notch filtering being a common example.


Again, given the question, no need to complicate the answer.

But you found it necessary to bring up loop gain. Interesting. You wouldn't
be an audiophool, by chance?

Loop gain greater than unity is what causes feedback howl. There is no
way of avoiding it if you want to explain what causes the feedback.

Wrong. *Regenerative* feedback needs a gain unity.

And make no mistake, the feedback the OP was asking about was the loud
howl you get when you turn the PA up too far.

You can't even keep *your* terms straight. You *must* be an audiophool (lack
of an answer speaks volumes).

I leave the verdict to the audience.

d