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Using 2x T-39 V coupled towards a wall, How far from the wall do my tops need to be before a delays are necessary? Will a delaying my tops be greatly beneficial under 40 ft from woofer cone to tops? I am thinking the Haas Effect would make it seem like there would be no great benefit. However in home audio setting the speaker distance in the setup only a couple feet off I have noticed a big difference. Basically is it worth the money to buy a couple Behringer Shark DSP110s or a DCX2496 for this?

My current setup is (for mobile DJ):
2x Behringer DSP415 (sometimes 4 of them)
1x Crown XTI 1000
1x BBE Sonic Maximizer 882i
2x T-39 20"
I have a DBX Driverack PX coming in next week and replacing the BBE

Also I am looking for a RELIABLE wireless mic for announcements, not pops, hisses, or cutting out. Sound quality for clear speech not singing, trying to keep under/around $200 150 ft minimum actual range if there are any suggestions.

Thanks
Dan

subharmonic wrote:Using 2x T-39 V coupled towards a wall, How far from the wall do my tops need to be before a delays are necessary? Will a delaying my tops be greatly beneficial under 40 ft from woofer cone to tops?

It depends how low you crossover. If it's 80 Hz or lower delay is of minimal concern. Use it if you've got it, don't lose sleep if you don't.

You'll want to delay the tops regardless of where you place the subs since the T39 has a ~8 foot horn path. That is, unless you plan to place the tops 8 feet -behind- your subs.

dude, you have have a crown xti 1000. It has built in delay....


if I put my tops on top of my t30s, I can tell that the bass is a tad behind the tops, I doubt anyone else notices, but I do. The t30 has 9 feet of throat (10?), so it has to travel 9 feet before you even hear it. if your tops are in front of your subs (relative to the audience) this is going to be exaggerated.

sine143 wrote:dude, you have have a crown xti 1000. It has built in delay....


if I put my tops on top of my t30s, I can tell that the bass is a tad behind the tops, I doubt anyone else notices, but I do. The t30 has 9 feet of throat (10?), so it has to travel 9 feet before you even hear it. if your tops are in front of your subs (relative to the audience) this is going to be exaggerated.

I thought the output delay was only for the signal going to the subs, not the one looped out to the PA speakers. That was my understanding, guess I didn't have time to play with it more yet. As for the subs usually will be off 20+ feet elsewhere behind the mains for most gigs given out setup

Bill Fitzmaurice wrote:

subharmonic wrote:Using 2x T-39 V coupled towards a wall, How far from the wall do my tops need to be before a delays are necessary? Will a delaying my tops be greatly beneficial under 40 ft from woofer cone to tops?

It depends how low you crossover. If it's 80 Hz or lower delay is of minimal concern. Use it if you've got it, don't lose sleep if you don't.
I consulted for 4 years at a large outdoor pavilion where there was lawn seating that began 200 feet from the stage, where the subs were stacked. EAW KF 850s, crossed at 80Hz, were tower mounted at the beginning of the lawn seating, delayed 200ms, but all of the below 80Hz information came from the subs an additional 200 feet away. You could not tell the difference.

Thanks, We have a wedding tonight so I will rework the crossover (currently at 100hz) and see if it sounds better.

subharmonic wrote: Thanks, We have a wedding tonight so I will rework the crossover (currently at 100hz) and see if it sounds better.

Just for grins, you can answer the question yourself. just add a delay of 8ms + 1ms for each foot the subs are behind the mains. Add the delay to the tops. see how it sounds - you know, take a walk around the venue, etc. If you don't like it, turn the delay off. I'd be willing to bet you'll prefer the sound with the delay.

subharmonic wrote:
if I put my tops on top of my t30s, I can tell that the bass is a tad behind the tops, I doubt anyone else notices, but I do.

If you notice 9ms you're crossed high, or with insufficient slope.

I thought the output delay was only for the signal going to the subs, not the one looped out to the PA speakers.

Backwards you have it. The mains are delayed, otherwise the lows reach the audience after the mids. But of far more concern than matching the subs and mains is matching the mains and the backline, when there is a backline, as in guitar amps, drums etc. with livesound. The mains must be delayed so that the sound from the PA doesn't reach the audience before the backline does, and at 500 Hz even 5ms is quite audible, whereas at 50 Hz even 50ms is not.

Bill Fitzmaurice wrote:Backwards you have it.

I know you're the wise sage around these parts, but you're starting to sound like Yoda, and it's kind of freaking me out.

jcmbowman wrote:

Bill Fitzmaurice wrote:Backwards you have it.

I know you're the wise sage around these parts, but you're starting to sound like Yoda, and it's kind of freaking me out.

hahaa oh man i thought the same thing until i put the emphasis on 'backwards, you have it' lol
great rule of thumb info here Bill thanks..

I understand I need to delay the mains but I have no means of doing that unless I read the XTI manual wrong. From my current understanding I can delay the XTI speaker level output but it is pushing the subs. I need some way to delay my mains, like the shark or dcx. Unfortunately I didn't have time to play with the delay settings as I was finishing my subs yesterday. I need to confirm or deny my current understanding of the XTI amp.

I just got back from soundcheck and played a little more with the cross over and noticed a big difference, I A-B'd a couple different settings and settles on the 45-80Hz with a 12db drop seems the best: 6db seemed a little sloppy sounding and 24db was too harsh. Time to change and go back to the venue

are your tops powered? I thought you were running a mono setup out of the xti.... my bad. Unless you are pushing tops with the xti, you cannot use its delay (it cant quantum tunnel your subs forward hehehe).

sine143 wrote:are your tops powered? I thought you were running a mono setup out of the xti.... my bad. Unless you are pushing tops with the xti, you cannot use its delay (it cant quantum tunnel your subs forward hehehe).

Sorry about the confusion. Yes they are powered tops. I guess I could check with LaForge in Engineering to see if a tachyon pulse from the main deflector into the XTI can cause a rip in time space. It worked on my George Foreman.

only if you happen to be in a Klingon bird of prey. Slingshot around the sun at warp 9ish and you should have perfectly timed subs and tops

The inability to time align powered tops unless you're driving them with a crossover with time align built in is one more argument against them. Convenient, but inflexible.