Please note that, in general, the EQ should be used to cut frequencies, not boost them.

Although it's possible to boost frequencies, since the EQ is digital, you might clip the signal if you boost. For instance, a 0db waveform, boosted with the EQ past 0db, played at 0db volume level, will enter the digital clipping realm. This is exacerbated if you throw loudness into the equation. In practice, this won't happen too often, but the more you boost the frequencies, the more of a chance this will happen.

But anyway, down to your specific question about the frequencies: I think you simply need to adjust the Q of the bands you're trying to boost. Widen the bandwidth of the boosted bands (reduce the Q) and I think it'll do what you're expecting it to do.

Before you read any further, make sure to check out the FAQ entry on "Q" and the equalizer...

Okay, my theory is that the 4-channel version of the equalizer might be using the same algorithm to decide the automatic Q width of each band as the 2-channel version. Resulting in too-narrow bandwith if you boost it very far off-center.

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Tony Fabris