Bruce,
Although i have yet to put forth any further comments on the speaker auditions, i have to disagree with some points.
The MA speakers are forward, but the upper end (lower tweeter frequencies) are smoothly reproduced. Something in the M60 or with its tweeter is causing an unpleasant resonance during that whistling passage and this is why i call the Axioms "bright". I reserve the word harsh for a speaker that consistently and constantly produces this effect but the M60s do not (source dependant). This whistling is a frequency in the very high end of midrange and in the lower end of the upper spectrum (a
human whistle tends to fall in the 1kHz to 3kHz area). To say that the MA or the Tannoys do not reproduce that whistling realistically or equally as annoying would be a fallacy. I have yet to hear a person's whistle that actually makes me wince like when the sound is reproduced by my M60s. Having heard this passage on several other well made speakers, i doubt it is the linearity of Axioms and the assumed 'lack' of linearity of other speakers that is causing this effect.
Secondly, the graph of the GR10 cannot be compared to the GR60.
There will be similarities but conclusions about the GR60 performance cannot be made from the GR10 graphs.
Note the differences between the M80s, M60s and M22s in an
overlaid graph. (M80s are the top line, M60s the middle line and M22s the bottom line).
If the scale up to 50Hz was removed increasing the amplitude of this chart it would make the differences alot more easy to read but we'll got with this.
There are many things one can pick out of this graph to see how these 3 speakers, with the same components and build design can still vary in some areas signficantly to make a difference noticeable to the ear.
M80s play louder. Well according to the charts that is true as noted by the higher SPL for the M80 UNTIL you reach the 3.5-5kHz range where the SPL narrows to a value for all 3 speakers that is probably indistinguishable by the ear. So the M80s play a louder range than M60s and M22s but
not equally across the whole spectrum.
M80s have more bass. I think the hump between 150 and 200Hz may have something to do with that.
I digress. Back to the idea at hand. If you try to view specifically the M60 and the M22 at 2.5-3kHz you will see nearly a difference of 4dB in 2 peaks with the M60 while the M22 remains more linear, pehaps with a slight dip. Since these spikes come into the range for human whistling, have we potentially found the culprit spectrum for our harsh whistle sound from the M60? Perhaps using the M22 and M60 in a comparison of this could resolve the hypothesis.
In any event, the point remains, without proper graphs for the GR60s or the Tannoys, or having talked with their engineers, we cannot say what has or has not been done in tweaking the sound of these brands and models and we cannot draw conclusions on their actual linearity. Personally i feel the tweeters from the Tannoy and the MA GR60s are very articulate (more so than the M60s, easily distinguishable while using the switcher) and were very equivalent in their sound reproduction. I had trouble finding any real difference in sound between them (the tweeters that is). Both portrayed a whistling sound that was annoyingly loud and forward (bright) but without making me wince and there is a harmonic reason for it. I'm just doubting that reason is because the M60s are playing the sound more realistically, or more linear.
