speaker delay?

You can't just guesstimate/measure the horn length and base the delay on the path difference. The combined acoustic and electronic response of each frequency range acts as a bandpass filter with its own phase response. You need to measure the devices under test to determine the delay required. A Behringer measurement mic is cheap and most software can be downloaded as a trial. Measuring will also let you get the best out of a digital crossover by tweaking the frequency response of each frequency range.

distance devided by speed of sound then multiply by 1000

what kind of delays do people use on their HD15 and X1's i use a 200mm delay on the x1's and reverse the phase 

doober wrote: The upper end would be out because these frequencies are coming direct from the driver, not through several feet of horn like the low frequencies do. The low frequencies are therefore delayed compared to the upper frequencies. This is what gives a scoop its distinctive sound.

Ohhh aye, I did know that the sound is slightly phased on scoops but I never thought that the high frequencies won't make it through the horn. It makes sense though!

I'm determined to learn everything about scoops... Thats the task I've set myself over the  past few days since I've been ill just sat on here all day. I have learnt a hell of a lot as well.

The upper end would be out because these frequencies are coming direct from the driver, not through several feet of horn like the low frequencies do. The low frequencies are therefore delayed compared to the upper frequencies. This is what gives a scoop its distinctive sound.

after going from using no delay on my bass,to exact correct delay settings,i can say i was really impressed ,and obviously,when both cabs are in phase,you are getting the full potential out of both cabs ,and not losing some db by not having each phase aligned.