I would say for a speaker +/-2.25db is a very good response for a speaker. However the premise of this post was to Eq. a speaker's response for a particular genre of music, in this instance rock music. That is what I have an issue with. That is not a good premise from which to design a speaker.
I think the only thing that divides us is the concept of designing in an FR based on musical genre. That I will vigorously claim is bad starting precept.
That wasn't really the premise of the post. I guess it could have been clearer. I wrote that there had been a discussion about what characteristics made a speaker work well for rock, and shared the findings.
Then I wrote that we had spent time to have our speakers work well on rock. This does not mean that is all we have been doing, or that we had done so at the expense of everything else. As I have stated several times, our goal is for our speakers to work well across all genres of music. It brings to reason that we have not EQed them exclusively for one particular genre of music, as that would be the complete opposite.
The reason I brought up rock specifically, is because it is a genre speakers often do not master, and as a consequence many people are looking for speakers that do that genre well.
I said that for rock, it would be good with a balanced top end:
The current Manta tune is basically +/-1dB from 400hz and up.
This is obviously favorable for other genres as well.
I said that for some tunes, a slight dip between 2-4khz could be favorable for some recordings:
The current Manta tune is ~1dB down in the 2-3,5khz area.
This is less than unintentional crossover dips in many speakers. Based on my extensive testing this works well across genres. It is just enough to take unwanted edge and harshness off recordings where this is present (rock or anything else), without diminishing clarity of others.
I said it would be good with a slight focus on the upper bass / lower midrange:
The current Manta tune has an intentional lift in this area anechocially, which translates to a balanced in-room response that gives a full, natural sounding midbass, as opposed to many speakers that are lacklustre in this important area.
This works well for both rock and other genres.
I said that it would be good with plenty of capacity across the frequency range:
The Manta does 96dB@1m with less than 0,5% THD across the board.
A commercial speaker will always be a set of compromises, and as any other manufacturer (one would hope) I make deliberate choices in this regard. That being said, I think future owners will find that the Manta is less of a compromise than most (bar the requirement of a subwoofer of course). The best possible in-room sound with a broad range of genres (not just "hifi music", and not just classical) will always be my top priority.