Indeed, right click image and open in new tab. It works on my PC...
I forgot to mention, the red line is the 3rd order harmonic and probably responsible for the edgy sound I noticed. The orange line is the 2nd harmonic.
To be honest, I build these speakers and then listened to them and was disappointed by the harsh sound they produced in the mid to lower treble region. I only carried out these measurements afterwards to be a little bit surprised to confirm my suspicion that this had to do with distortion caused by driving the tweeters from too low frequencies.
Increasing the cross-over totally changes the sound quality in this critical hearing range! It really makes the CBT36 much more a high-end speaker!! It is a bit of a mysterie to me why Keele didn't notice the distortion. I guess his decision to use the 1khz cross-over was primarily driven by the desire to minimise interference due to driver spacing, but honestly I cannot hear any of this when using 3khz as cross-over. In fact Keeles next design (the CBT24) uses full range drivers only and he told me that interference due to driver spacing was really not as audible as one may expect.
Before the CBT36 I had hypex driven loudspeakers using mundorf amt tweeters--VERY good tweeters! With the cross-over modification on the CBT36 it is simply spectacular how well the sound quality of the cheap tweeters used in CBT36 compares to these expensive amt tweeters in terms of distortion. The sound dispersion of the CBT36 is of course much better, so all in all a big improvement relative to my previous speakers!
I forgot to mention, the red line is the 3rd order harmonic and probably responsible for the edgy sound I noticed. The orange line is the 2nd harmonic.
To be honest, I build these speakers and then listened to them and was disappointed by the harsh sound they produced in the mid to lower treble region. I only carried out these measurements afterwards to be a little bit surprised to confirm my suspicion that this had to do with distortion caused by driving the tweeters from too low frequencies.
Increasing the cross-over totally changes the sound quality in this critical hearing range! It really makes the CBT36 much more a high-end speaker!! It is a bit of a mysterie to me why Keele didn't notice the distortion. I guess his decision to use the 1khz cross-over was primarily driven by the desire to minimise interference due to driver spacing, but honestly I cannot hear any of this when using 3khz as cross-over. In fact Keeles next design (the CBT24) uses full range drivers only and he told me that interference due to driver spacing was really not as audible as one may expect.
Before the CBT36 I had hypex driven loudspeakers using mundorf amt tweeters--VERY good tweeters! With the cross-over modification on the CBT36 it is simply spectacular how well the sound quality of the cheap tweeters used in CBT36 compares to these expensive amt tweeters in terms of distortion. The sound dispersion of the CBT36 is of course much better, so all in all a big improvement relative to my previous speakers!
