I think this is worth a little bump...
Quote:
Originally Posted by takman  |
A couple things.. I think it would be clearer if you removed the light-green
fill below the plot. Are both monitors sounding for this test ? I think it would
be best if only one monitor was used to make it easier to see which reflections
are coming from which speaker. Your microphone was at the listening position ?
If each peak is a reflection your first obvious one looks to be at about 1ms.
Is there anything a bit over a foot away from your monitor ? The next
largish reflection is at about 4ms or 5ft away. If both monitors were
active could this be from the other monitor ?
I
think this is how you're supposed to use an ETC plot. Everything that
arrives at the listening position that is not the direct signal is a reflection
and shows up as a peak. For a reflection not to cause smearing of the
sound it has to be quite a bit lower in intensity than the direct signal
(it also can't arrive too late or you'll get an echo). You want as many of
these lower reflections as possible (a diffuse field) and you want them all
to decay exponentially in a reasonable amount of time.
I see in your case all reflections die down after about 400ms, which doesn't
seem so bad. My mostly empty untreated room goes on for 700ms (on the ETC,
the room itself continues to ring much longer than that).
Paul P