Guys this stuff is so good, I just have to share it with you.
When I design a set of speakers, I don't just look at an on axis response to dial it all in. I look at off axis responses in the vertical and horizontal plane.
This can bring to light problems that are not seen in an on axis response. Such problems can be baffle reflections, and driver cancellation from driver offset changes as listening or measuring points move.
This speaker not only has no vertical or horizontal off axis problems but is extremely good on both axis.
Below is the horizontal off axis responses taken at one meter.
The Red line is on axis.
The Orange line is 10 degrees off axis. Hardly any change except at 20kHz.
The Yellow line is 20 degrees off axis. Still nearly dead flat!
The Grey line is 30 degrees off axis. It is still within a +/-1.75db range!
The Black line is 40 degrees off axis. From 250Hz and up it's still within +/-2.5db.
Man the off axis response of that ribbon is killer! A 3/4" diameter dome tweeter can't even do that.
Now most people tend to think that the vertical response from ribbons is poor, and for many longer ribbons this is true, but this one isn't very long. What I really like is the smooth output level across a wide range, and this speaker has it in spades.
See off axis vertical response below.
The mic was pulled back to 60", and this is why we see the sensitivity across the board falling off.
The first line, the Red one, was taken on tweeter axis with the mic at 39" from the floor.
The second one, the Orange one, was taken with the mic moved up to 43". There is hardly any change.
The third one, the Yellow one, was taken at 47". It still looks great and shows that the drivers are acoustically in phase very well. From the back of my room and standing (I am 5' 10" tall) this brings the mic to just below ear level, but close. If I were to step back another foot or two then this would be at ear level.
The last one was taken with a mic height of 51", the Grey line. This is above ear level to me and would be even to a really tall person. We are still looking at a +/-2.5db range, and the highs did not fall out of it in the top end. In fact it appears that the peak in the top may be a little hot straight on but off axis it is as much a blessing than a curse.
A speaker with an on axis and an off axis that is this smooth is rare. The total in room response of this speaker will look very good. I like this speaker the more time I spend with it.
