Bob,
I suspect the dip occurs at resonance of box and driver system (see the impedance curve). The port looks like it is tuned around 40 HZ (low impedance point) to get better bass extension - this will introduce phase delays around that frequency and affect the transient response.
You are right that a small speaker and a separate sub tends to get better results (like the NHT XD). There are also some monitors that are small without reflex ports that will sound more accurate in the bass and lower mid (but at a risk of sounding a bit bass shy). Alternatively a bigger box speaker is the way to go.
However, I felt that the JM Lab Chorus 706 distortion extended too far up into the lower mid range for comfort (but you can't be too picky with a $450 price tag which makes it a real bargain).
I just suggested to investigate the Solo6 based on its superficial similarity to the Chorus 706. The "pro" monikor and active design suggests it should be better...
I suspect the dip occurs at resonance of box and driver system (see the impedance curve). The port looks like it is tuned around 40 HZ (low impedance point) to get better bass extension - this will introduce phase delays around that frequency and affect the transient response.
You are right that a small speaker and a separate sub tends to get better results (like the NHT XD). There are also some monitors that are small without reflex ports that will sound more accurate in the bass and lower mid (but at a risk of sounding a bit bass shy). Alternatively a bigger box speaker is the way to go.
However, I felt that the JM Lab Chorus 706 distortion extended too far up into the lower mid range for comfort (but you can't be too picky with a $450 price tag which makes it a real bargain).
I just suggested to investigate the Solo6 based on its superficial similarity to the Chorus 706. The "pro" monikor and active design suggests it should be better...