Audio Equalization, Is Parallel or Cascade better

Question

I'm not really an audiophile, so I can't determine the difference. I was playing around with Matlab's Graphic EQ and I noticed that there is a difference in the Magnitude response for the same gain between parallel and cascade. I understand that there is a difference graph-wise because in cascade, the magnitude response adjusts around its center frequency according to the command gain but is ~unity otherwise. Parallel however has a resonance at the center frequency and has low gain at other frequencies. But when I listen to the audio, I can't seem to hear the difference?

So if the difference in sound is negligible for non-audiophiles like me, what would be other advantages if I were to choose what would I use? Are they also equal in processing delay, complexity in implementation or number of calculations, and/or memory? Or any other factors?

Thanks in advance!

Answer 1

I very much prefer cascade where the individual bands are implemented as peaking filters. This way the EQ is truly flat if all gains are 0 dB and it's very cheap to implement (one biquad per band). On the downside, they are a little harder to update especially if it's supposed to be "click free" .

Parallel EQs often end up with residual pass band ripple and significant group delay distortion even if they are nominally flat. It's also more expensive to implement.