Waveguide Transmission Line Monitors

[xrk971]

You need to apply some padding to the tweeter to reduce its shelf by about -6dB, otherwise it will sound unbalanced and lacking bass and warmth. The truth is, overall speaker sensitivities can be no higher than the woofer's sensitivity at about 80Hz to 100Hz after baffle step losses. The best non pro-audio type woofers are maybe 90dB - thus a tweeter will generally have to be attenuated down to circa 85dB. 94dB sensitive dome tweeters in a waveguide gain additional sensitivity so will have to be padded down even more.

Any non PA speaker claiming to be greater than 85dB sensitive is basically lying (or claiming it at 1kHz which is a worthless place to be claiming sensitivity as it's not the rate limiting step).

Here is where I ended up on mine. Woofer is 90dB sensitive and overall I am at 84dB or so.

 

[zcables]

Very helpful information; thank you! This is a calculated 2nd order XO that brings down the tweeter level another few dB, as well as attempts to smooth out the system response around 1000hz. I have a lot more reading to do...

 

[zcables]

Constructed the 2nd order crossovers last night and switched the polarity of the tweeters; I read that's beneficial due to the 180 degree phase shift. I'll hook them up today start testing.

 

[zcables]

I did many listening test over the weekend, and the speakers sound very good. They are very detailed and a little forward on the top end (which I like), and strong bass down far enough for all music except the very bottom a of cathedral organ. It's a very enjoyable listening experience, except there seems to be a phase issue.

If I'm sitting in the listening position, everything sounds good until I move my head side to side and the center of the image jumps between ears. I wired these with the phase on the tweeter reversed to the woofer due to the second order crossover, so I swapped that back mid listening session and the issue didn't change. I'll go through and double check the crossover construction, but I know that crossover design and sound reproduction is much more complicated than even software can make it look.