Does this apply to our BF cabs ?

[djtrumptight]

i bought one of these sound level meters today and i ran across this video and i wonder does this also pertain to our cabs or does he need to do this because he has 12 dual 18's under the stage improperly lined up ?

http://www.youtube.com/watch?v=A-uh0hwtspE

[Frederic Gelinas]

Did he say that the delay should be re-adjusted if you change the crossover point? Why?

[DJPhatman]

i bought one of these sound level meters today and i ran across this video and i wonder does this also pertain to our cabs or does he need to do this because he has 12 dual 18's under the stage improperly lined up ?

http://www.youtube.com/watch?v=A-uh0hwtspE

Perfect example of a self-proclaimed "pro" who has not clue one about sound and acoustics. Improperly deployed (horizontally splayed) tops and separated subs = huge "suck" button.

[Bruce Weldy]

Perfect example of a self-proclaimed "pro" who has not clue one about sound and acoustics. Improperly deployed (horizontally splayed) tops and separated subs = huge "suck" button.

The video was about time-alignment, not speaker placement. While most of us can time-align much easier by taking a simple measurement - his situation was different with the tops hung so high. His approach makes a lot of sense and is sound advice.

It's just not going to come into play for the majority of us with speakers only 6 feet off the ground.

As far as his having a "clue" about sound....I don't recall him saying that he designed and/or installed the system. Not everyone has a line-array available to work with. If those boxes have a narrow-enough horizontal dispersion (some of those kind of boxes are designed for that very use), it can work just fine.

[Bill Fitzmaurice]

If those boxes have a narrow-enough horizontal dispersion (some of those kind of boxes are designed for that very use), it can work just fine.

No matter how narrow the dispersion angle you will get combing, as there will always be overlap of the output patterns of the individual cabs. Some boxes work better than others, but none have the capability to defy the laws of acoustics.

[Bruce Weldy]

If those boxes have a narrow-enough horizontal dispersion (some of those kind of boxes are designed for that very use), it can work just fine.

No matter how narrow the dispersion angle you will get combing, as there will always be overlap of the output patterns of the individual cabs. Some boxes work better than others, but none have the capability to defy the laws of acoustics.

No, but it also doesn't mean that the sound will suck either (as referred in the earlier post) . It may not be optimal, but it may still sound just fine. I will never argue theory with you because I'm not educated enough to do so, but in application, the comb filtering may be virtually unnoticed to any but the most-trained ear.

Might a line array sound better? Sure. But does every system that's not a line-array suck? Not by a long shot. That was my point.

[DJPhatman]

Perfect example of a self-proclaimed "pro" who has not clue one about sound and acoustics. Improperly deployed (horizontally splayed) tops and separated subs = huge "suck" button.

The video was about time-alignment, not speaker placement. While most of us can time-align much easier by taking a simple measurement - his situation was different with the tops hung so high. His approach makes a lot of sense and is sound advice.

It's just not going to come into play for the majority of us with speakers only 6 feet off the ground.

As far as his having a "clue" about sound....I don't recall him saying that he designed and/or installed the system. Not everyone has a line-array available to work with. If those boxes have a narrow-enough horizontal dispersion (some of those kind of boxes are designed for that very use), it can work just fine.

In the first 10 seconds of the video, and in the description, he claims to be a "sound engineer". Open mouth, prove ignorance. This aspect alone causes so much doubt, in my mind, as does checking out some of his other "pro audio" videos. No offense, but I tend to not listen to anything that comes out of the mouth of a

To fix the poorly deployed system, and most likely improve the sound over and above time-alignment, is as easy as unplugging the 4 outer-splayed tops, and 8-10 of the 12 ( ) dual-18 subs. But, checking his other videos, you will find that he always deploys with split subs, because it "sounds better". So, will the sound suck? You bet your ass it will, as the comb-filtering, power alleys and voids will be rampant.

And if you wish to tell me that speaker placement does not effect time and phase alignment, then...

[Bill Fitzmaurice]

But does every system that's not a line-array suck? Not by a long shot. That was my point.

I wouldn't say all cluster arrays suck. But during my tenure at a major concert venue during the transition period by pro-touring sound companies from cluster arrays to line arrays I found the best cluster arrays didn't sound as good as the worst line arrays, while the worst cluster arrays were horrid. Keep in mind that the cost of each cab used by pro-touring companies runs between $5k and $10k, with the minimum complement being twelve cabs for even a 3,000 seat room, so they did not take lightly the expense involved.

[Bruce Weldy]

But does every system that's not a line-array suck? Not by a long shot. That was my point.

I wouldn't say all cluster arrays suck. But during my tenure at a major concert venue during the transition period by pro-touring sound companies from cluster arrays to line arrays I found the best cluster arrays didn't sound as good as the worst line arrays, while the worst cluster arrays were horrid. Keep in mind that the cost of each cab used by pro-touring companies runs between $5k and $10k, with the minimum complement being twelve cabs for even a 3,000 seat room, so they did not take lightly the expense involved.

No question they are better. But we don't always get what we want. My point is that this notion that there is only one way to do it is silly. It's not a black and white world in sound. There are great systems, good systems, ok systems and awful ones. I've heard good sound on Vertecs and I've heard good sound on cheap boxes on sticks. I'm way more impressed with someone who makes junk sound good, than one who makes great stuff sound like crap.

I love my BFM boxes and will build more. I will educate everyone I can get to listen to me about how things should be done - but I'm not going to slam 'em just because they don't see it my way.....as long as they make it sound good.

[Bruce Weldy]

Perfect example of a self-proclaimed "pro" who has not clue one about sound and acoustics. Improperly deployed (horizontally splayed) tops and separated subs = huge "suck" button.

The video was about time-alignment, not speaker placement. While most of us can time-align much easier by taking a simple measurement - his situation was different with the tops hung so high. His approach makes a lot of sense and is sound advice.

It's just not going to come into play for the majority of us with speakers only 6 feet off the ground.

As far as his having a "clue" about sound....I don't recall him saying that he designed and/or installed the system. Not everyone has a line-array available to work with. If those boxes have a narrow-enough horizontal dispersion (some of those kind of boxes are designed for that very use), it can work just fine.

In the first 10 seconds of the video, and in the description, he claims to be a "sound engineer". Open mouth, prove ignorance. This aspect alone causes so much doubt, in my mind, as does checking out some of his other "pro audio" videos. No offense, but I tend to not listen to anything that comes out of the mouth of a

To fix the poorly deployed system, and most likely improve the sound over and above time-alignment, is as easy as unplugging the 4 outer-splayed tops, and 8-10 of the 12 ( ) dual-18 subs. But, checking his other videos, you will find that he always deploys with split subs, because it "sounds better". So, will the sound suck? You bet your ass it will, as the comb-filtering, power alleys and voids will be rampant.

And if you wish to tell me that speaker placement does not effect time and phase alignment, then...

Wow.....I wish I had magic powers so I could hear stuff with my eyes.

The OP asked if his approach to time-alignment was valid. It is....but probably not that useful for 99% of the guys on this board because there is an easier way.

But, you elected to disparage the guy and his system without ever addressing the issue at hand. That's not necessary or germane to the question at hand.

[SeisTres]

oh wow, well this thread got derailed big time.

And no, this applies to every cab out there not just his arrangement. However, I would not apply delay this was as delay should be used for time alignment of the cabs. What he's doing is phase aligning the system at that particular frequency. That's the reason why he mentioned having to change delay if xover frequency is changed because the cabs will have different phase different frequencies and will have to aligned all over again.

Which is still ok as a steep xover will be used and the cabs will be the same through out the show. But still, for time alignment, it is simpler to calculate the distance between source of sound, delay that, xover properly and then just rta the whole system as a whole.

[Bill Fitzmaurice]

And no, this applies to every cab out there not just his arrangement. However, I would not apply delay this was as delay should be used for time alignment of the cabs. What he's doing is phase aligning the system at that particular frequency. That's the reason why he mentioned having to change delay if xover frequency is changed because the cabs

I didn't watch more than the first few seconds of the video to see what it was all about, but if what you say is true then yes, clueless he is. And since one usually uses a measuring tape for the purpose of time align, not a sound meter, I suspect you're correct.

There is a method with which one would use a sound meter. The tops and subs are placed out of polarity, with a test tone played at the crossover frequency. The delay is then swept until the meter gives the lowest reading, indicating that the subs and tops are 180 out of phase at the crossover frequency. The cabs are then put back into proper polarity. But the amount of delay would be the same irrespective of the crossover frequency.

[Michael Ewald Hansen]

And no, this applies to every cab out there not just his arrangement. However, I would not apply delay this was as delay should be used for time alignment of the cabs. What he's doing is phase aligning the system at that particular frequency. That's the reason why he mentioned having to change delay if xover frequency is changed because the cabs

I didn't watch more than the first few seconds of the video to see what it was all about, but if what you say is true then yes, clueless he is. And since one usually uses a measuring tape for the purpose of time align, not a sound meter, I suspect you're correct.

There is a method with which one would use a sound meter. The tops and subs are placed out of polarity, with a test tone played at the crossover frequency. The delay is then swept until the meter gives the lowest reading, indicating that the subs and tops are 180 out of phase at the crossover frequency. The cabs are then put back into proper polarity. But the amount of delay would be the same irrespective of the crossover frequency.

That is actually exactly what he does later in the video

[Bill Fitzmaurice]

That is actually exactly what he does later in the video

Like I said, I didn't watch it past the first few seconds. But if he does use that procedure the result will always be the same irrespective of the crossover frequency.

[Bruce Weldy]

As I stated earlier, it made sense to do it that way as the speakers were quite high up and back a little from the subs. Something we (99% of us) will never need to do as we tend to have the tops low enough to just step it off.

I'm sure he used the crossover point as his reference since both the tops and subs could put out that frequency....

Bottom line is, his procedure was valid.....even if his accent was more hick than mine.