The first thing is to know the difference between
EQing the
HOUSE &
EQing the mic’s
If you don’t start with a
flat HOUSE you will be fighting yourself every time.
Send pink noise through the
system to get a
flat response from your speakers , with a
RTA if you have one
& getting a good sound from any mic will be easier. ( with the ch EQ )
I have to disagree with this. First, a
flat response is not always the most desirable response, just like many other aspects of audio you need to consider the situation as different situations may relate to different goals. For example, a
flat response may be desirable as a baseline response for a tour
house system but it may not be what is desired for a
system that is focused on speech intelligibility, a
stage monitor or a
system used for some genres of music.
Second, it is important to realize that the
system response can vary throughout a
venue. It is virtually impossible to get the same response throughout a large listener area, thus what can be important is developing a feel for the general goals and how any adjustments made for one location may affect other locations. In some applications it may be decided to optimize the response for some specific seats even if at the expense of others while in other applications the goal may be to balance the compromises at any seat, with the result that no seat has the actual desired response.
Third, while a
RTA is better than nothing, it is limited and especially in the hands of anyone who does not understand all of the factors that may be affecting the
frequency response shown. Rather than try to
address the subject all over there is a good synopsis at
http://www.bennettprescott.com/downloads/devil_with_rta.pdf. The bottom
line is that relying solely on a
RTA can lead to spending hours trying to
address something that doesn't really matter or that can't be fixed with equalization. Tools such as dual
channel analyzers can show additional information that can be very useful but that also requires sufficient understanding of what is being shown and what it represents.
A concept that was sort of a breakthrough for me was when I realized that tuning an audio
system is actually trying to
address several potential factors. The general concept is that a
system tuning may often be trying to
address:
- Individual speakers.
- Speaker arrays or clusters.
- The effects of nearby surfaces.
- The effects of multiple, physically separated sound sources.
- General room acoustics.
- Gain before feedback.
- Subjective or artistic considerations.
Every situation may be slightly different in terms of the factors involved and which can be modified or adjusted, the
system tuning tools available, the
system analysis tools available and how effectively they can be applied, the goals and so on. Some tuning aspects may be addressed by the equipment manufacturers and some may be set once and not have to be adjusted while others aspects may be different for each use. But the concept that you are actually usually addressing multiple facets really helped me better understand the tradeoffs and goals involved and especially what may or may not be important or possible to see and/or
address with the tools available.
In general, I believe that it is important in
system tuning understand what you are trying to achieve and what is possible, that is where the
level of experience and knowledge may impact what is possible. Anyone with
pink noise and a
RTA may be able to make improvements, but they may be limited in the improvements possible or understanding how what they do
in one area may affect others. And in the end, no matter what tools are used for the analysis or tuning, it has to sound good to the listeners.
