Quote:
JohnM wrote:
 That's not correct. The windowing effects are the cause of the response across the freq band not dropping sharply to the noise floor when no filters are active, but every EQ filter (gain or cut) rings at its centre frequency, the higher the Q (the narrower the bandwidth) the longer it rings. The ringing is easily observed in the impulse response by setting up the BFD in loopback and making a measurement with a sharp filter, it is more obvious with boost than cut but both ring. It is because of this time domain behaviour that EQ filters are able to counteract the ringing of modes, the decay of the EQ filter's attenuation over time matches the decay of the mode's gain, when the filter is properly set to match the mode's bandwidth and gain. |
So, can I assume that would part of the key to using the waterfall to tweak your response...adjusting the bandwidth of the filters to modify the waterfall plot?
What is the ideal decay rate (or realistic desired decay rate where sound quality is not compromised - i.e. we obviously aren't listening in anechoic rooms), or do we just want it to be relatively even across the frequency response?
I guess could also be said that boost in particular should be performed at as wide a bandwidth as possible, with subsequent cuts to included peaks, instead of boosting individual dips - which is more likely to introduce ringing?
This is a very informative thread - it motivated me to pick up a sound card yesterday.
Pete