ADDICTED! thats what you are! You will never be able to walk into another place with sound production without RIPPING the system apart!
Gadget,...You are correct!... I have a renewed interest in audio and it has become an ADDICTION!... I have found this PA stuff to be much more exciting than the audiophile gadgets (pun) I owned in the 1970s... Heck...I had shelves full of stuff including: Numark EQs, MXR dynamic range expander, Nakamichi Dragon, Yamaha high speed DC amp, linear tracking turntable, Marantz receiver with preamp out, six Advent speakers, etc., etc... And nowadays I just have one of those Bose Lifestyle 35 systems... So this install has been extremely challenging, rewarding, and great fun!... You are absolutely correct in that now I am totally aware of any sound reinforcment, and I listen to it very carefully to compare it to the one I installed... And of course,...the youth center system always blows them away...
Remember that in the driverack where the signal is digital.. it no longer acts as an analog signal where signal to noise is key and you need as much signal as possible to push the noise floor down...so get that mixers masters to right at clipping.. occasionally for the gain setup.
Which mixers masters?... The real mixer masters or the ones inside the DriveRack?... Would you please clairify (I mean...spell it out) your "Super Duper Gain Structure Procedure" once you get to the DriveRack... I'm not sure but I could still be under gained here?...
As for the limiter those are called artifacts as the limiter "hunts" for something to do, and as it reacts to them. As usual Kevin .. spot on...in thought process and implementation!
I have had the 'EXACT' same experience with the peak-stop and auto-on functions in the DR. I would like to know what is up with that, but haven't had time or priority to dig deeper into that. Let me know what you find.
Gary,...question: If you were me...would you just go ahead disable those suckers on the other channels?...
As for the deal about adding speakers to lower the impedence.. thai is true, but you need to remember you need to divide the available power by the number of drivers... sure you might get a 50% increase in power but you have also doubled the number of drivers...
So...I'm assuming by doubling the drivers I would also double the bass response or output?... If so I'm going to keep my eye open for another good set of used VRS18s...
you may want to copy your current playback program into a new 'development' space and try autoEQing the room again but with a different response pattern like A, B, C or whatever to see what sounds best. I have noticed that for strictly playback these curves can sound much more like cinema sound that we are all used to.
Wolfgong,...Another excellent idea!...:idea:
Wolfgong or Gary,...Just curious: Is there a different response pattern (it's currently flat) that you would suggest I try for DVD movies and/or CD music?...
I'll tell you whats next... lots more learning.. and experimenting... remember there is no right or wrong way of doing things.. only the results that determine if a thing was worth doing or not!
And...I LOVE IT!
Kevin
Gary,...I forgot to mention: I just returned from praise team practice but I was running behind in getting there... I realized by just HPF-ing everything except the bass and keyboards (drums are acoustic and not miked) that there was a MAJOR IMPROVEMENT in the mix... They practice again this Sunday afternoon before service so I plan on trying some of the other things you suggested...
Regarding drive rack autoEQ response patterns: I only had time to try response A. It sounded pretty good just for playback.
What you can do is go into the EQWizard and when you get to the step that prompts for a response pattern you can dial through them and see a image of what each pattern looks like in the tiny little screen.
I think the one I used had a dip at about 250Hz and a bump to the left and a rising curve to the right.
I hope this helps. I can't do much more for you right now as I don't have a unit hooked up that I can look at.
Kevin..
I was talking about the masters on the Allen and heath
Set the input volumes on the Driverack just below clipping with the mixer clipping... ABSOLUTELY NO clipping on the outputs...
Amps to clipping, then back off a few DB for headroom...
The typical favorite seems to be the \"C\" curve for rock music... I have stored all of them after I got flat first...It's simple to do with the \"indoor method\"
Leave the limiters on, but kill the auto and if possible the brick walls... if you have sufficient headroom the limiter should never normally hit anyway...
If you set the limiters on the amps you are relegating yourself to only about 1700 watts in bridged mono... let the Driverack do that
It's not quite that simple with speakers.. it's like jets.. two jets isn't twice as loud as one... it takes three... you get the 3db of free gain though... Remember that if you have a 200 watt amp to get twice as loud you would need 10 times that power or 2000 watts.
UUFDA I'm pooped.. good weekend though.. excellent band!
Thank you so very much for the valuable information!... I'm heading to the youth center right now to re-check the gain structure because I know that I'm still short of having set-up correctly in the DriveRack... I will also disable the clip limiters on the six PA amplifiers and turn off the \"auto-on\" and \"peak-stop\" artifacts on the other channel limiters inside the DR260... I want to get this done today before the 4:30 praise team practice...
I just looked at sound job for a new beauty salon in Lexington... It looks like a 70.7 volt system will work best for this application... I was able to quote this system (installed) for just under 6K... I quoted using the following items (I only gave descriptions to customer):
It's an open station beauty salon so they only want background music that they can easily talk over (imagine that...20 women or so), with no zone control, no volume attenuators (except main system volume) and no voice over paging... Anyways,...it's going to be a pretty simple setup...for now... I've already considered some what-ifs,..and I'm planning ahead to accomodate any foreseeable expansions...:)
I am curious to hear what Gadget says. I have not done this, but I think that this would work.
Either play a track (or live) of a kick drum hitting at 1 sec intervals or so. Maybe put a gate on it with fast attack and release, and no other effects. When the delay is right it should be loudest and tight.
I have tried using the sample loop on my CD player and find a good kick hit with resonable results. It just time consuming finding the right spot with out too many artifacts. I may make myself a CD when I think to do it and feel in the mood.
Either play a track (or live) of a kick drum hitting at 1 sec intervals or so. Maybe put a gate on it with fast attack and release, and no other effects. When the delay is right it should be loudest and tight.
Dra,...So what your suggesting is by tweaking the limiter you may be able to tune subs for a more punchy bass?... I would be very interested in this as well!...:)
What is your preferred method of setting the delay between your mains and subs?...
Kevin, get much sleep last night? I was talking about setting the delay. What I was saying was that if you had a frequency band wide enough to cover the x-over point that was chopped into intervals, then when the subs were aligned with the top cabs it would be louder and tighter as you swept the amount of delay.
Hmmm.. see what happens when you sleep... A guy can miss out on SOOOO much...
First off let me say that there is no way you'll ever get the time alignment perfect...it AIN\"T gonna happen. Whats right at the crossover point isn't necessarily going to be right 20 hz above and below the crossover.. here we should also add that there is also phase to take into consideration...Phase when done properly will always end up somewhere between 0 and 180deg's...never exactly -0- or -180- degrees...(oops! there's those nasty absolutes cropping up again.. I HATE.. OOPS.,. there's another of my pet peeves... but I digress.. as usual...) The \"Ideal\" alignment will be a compromise at best. that said here's a tried and true method thats fairly easy and quick...but \"your mileage may vary...\"
We will assume a 100 hz crossover point for this exercise.. again \"your crossover point may vary\"...One side of the PA running ONLY! copy the settings to the other speaker or use 'linked stereo'. Play a 100 hz tone with your handy dandy signal generator with equal volumes coming from both subs and tops (of the 100 hz tone). Invert the phase of the subs (thats accessible by left clicking on the numbers of the individual outputs at the far right of the GUI. Turn the polarity phase on and if its set at pos... select neg...) sweep the delay of the tops till the 100 hz is almost canceled. Invert the phase of the subs back and see if there is a large dip on either side of the 100 hz... if so you may be exactly 10ms off... Easily checkable...
Now lets talk a bit about phase... this is the way we see if we can balance the sound of the crossover point with the adjacent frequencies. using the RTA play a pink noise signal and note the bands below the 100 hz crossover point. If there are large peaks (or even if not try this) again using the polarity/phase control we spoke of earlier..turn on the module, make sure it's on the normal polarity for your setup and sweep through the phase till the response on the RTA smooths out...this is only as accurate as the resolution of the RTA, and frankly 28 bands is like using BOZO's shoes to try and navigate a mine field... There are RTA's with upwards of 128 sampling points and more...Like the 'True RTA.. a free.. to moderately cheap depending on features RTA...downloadable...thats another discussion..
Thats it.. again there are more accurate ways with TEF and SMAART type alignment tools.. but only a few have the tools, and actually CAN do this properly.
Perhaps Mikey is lurking and would consider chiming in?
Gadget
:arrow: You do realize that we have only barely scratched the surface on this audio stuff.. don't you :?: :shock:
Excellent!... That is an ingenuous way to set the delay using the tools at hand!... It makes practical sense that the delay will cause cancellation of the mains and subs...if they are 180 degrees out-of-phase and timed properly... I love it!...
For my scenario I'm assuming I should follow this procedure for the flying (JRX115i) mains and the subs,...and then repeat it for the floor (JRX125) mains and the subs?...
Also,...for my scenario...would you recommend just a tad of compression (without make-up gain) for our "live program"?... If so,...where should the compressor be inserted in the signal chain and what would be some good preliminary set points?... Do I need or want the Notch Filter in the chain?...
This is the main chain I currently have for the "live program"...
You do realize that we have only barely scratched the surface on this audio stuff.. don't you
Yep,...I'm just taking baby steps one at a time... I think have the crossovers, gain structure and GEQ pretty well down for now,...so proper delay is next on my long list... I like having a good understanding or being some what confident in one subject before moving-on to the next one... Maybe compression (if you think it could help) and then feedback control are next?...
Kevin, get much sleep last night? I was talking about setting the delay. What I was saying was that if you had a frequency band wide enough to cover the x-over point that was chopped into intervals, then when the subs were aligned with the top cabs it would be louder and tighter as you swept the amount of delay.
Dra,...I have read exaclty what you described on another forum somewhere... I hope to realize more punchy bass if I can get the delay(s) half way close to being right...:?
To me the notch filter is most useful if you are maxing out your AFS filters and need more. A very little bit of compression might be beneficial. But in your application, could be very beneficial, if the following is true. Does the preacher get overly excited and loud at times? Compression would work great for this, but you'd need to punch it in and out. Now, if the band ever plays background while he speaks, that could be a problem. Auto-gain could also be used while he speaks, if he tends to get soft. Again, would need to be punched in and out.
Assuming......I think I'd lean for compression ahead of AFS. I also think I'd lean for AFS ahead of compression. In other words, do I want to quash potential feedback induced by volume (compressor 1st) or potentially trigger the compressor if feedback starts to occur (AFS 1st). Did that make sense? I'm not sure I undersatood it.
To me the notch filter is most useful if you are maxing out your AFS filters and need more.
On one very cloudy day (the next day after the mixer crashed) Gary walked me through using the PEQ's for additional AFS... I thought it was pretty cool because you can be more channel specific (if that makes sense?) by selecting individual channels (in muting the others) while using this method... He showed me how to use the AFS for doing this by clearing the live filters and turning off the filter lift to identify the problem frequencies and then one by one setting the PEQs to suppress the feedback... This is done "live" by using a microphone in different locations with the gain turned-up while ringing-out the system
To me the notch filter is most useful if you are maxing out your AFS filters and need more. A very little bit of compression might be beneficial. But in your application, could be very beneficial, if the following is true. Does the preacher get overly excited and loud at times? Compression would work great for this, but you'd need to punch it in and out. Now, if the band ever plays background while he speaks, that could be a problem. Auto-gain could also be used while he speaks, if he tends to get soft. Again, would need to be punched in and out.
Yes,...the minister fluctuates allot while he is speaking and at times the vocalist(s) as well... I was kinda hoping to do a mild catch-all or set-n-forget compression if it would add any benefit... I think I'd rather not have any at all...if I would need to toggle it... I want to keep this system simple,...and eventually (regrettably so) I will need to wean myself off of it...:(
Assuming......I think I'd lean for compression ahead of AFS. I also think I'd lean for AFS ahead of compression. In other words, do I want to quash potential feedback induced by volume (compressor 1st) or potentially trigger the compressor if feedback starts to occur (AFS 1st). Did that make sense? I'm not sure I undersatood it.
Almost sounds like the chicken and the egg mystery...:)
Gary walked me through it as an exercise but afterwards I put everything back to its original state... I hope to start from scratch again in the very near future to get it set-up for good... It really takes two people to do it correctly I think... One person should be moving about the stage with the microphone held in different directions while the other person is selecting the channels, adjusting the gain, watching the AFS to catch the ringing frequencies, and setting the PEQs...
Gadget,...Thank you for another enlightening conversation!...:brown nose:... They still haven't got an emoticon for that...
It is definately going to take two people to set the delay as you suggested...one to stand between the sub and main and the other to sweep the delay... The subs and mains are about 10-12FT apart... The floor mains are about 8-10" out from the wall but directly under the flying mains... The subs are in the corners and facing-out on the diagonal... Sooo...here's a stupid question: Should the person that is listening for the cancellation point be located directly in front and centered between the sub and main being tested?...or should they be directly centered between the two in both directions?...or should they be directly centered between the two while dancing in circles with a beheaded chicken?...
Also,...I have read that some people like to set a small gap between the crossover points instead of a small overlap... They claim it gives them more of a "studio sound"... Since you been around-the-block a few times I would like your thoughts on this...
I finally got back to the youth area today to set-up the delays between the mains and sub. Your technique worked beautifully! Instead of using my poor hearing I used the RTA mic and placed directly between the mains and sub. I first muted everything but the right sub and noted my volume level with RTA at the crossover point tone. I then muted the sub and enabled the right floor main. I used the amp attenuator and brought it up to exactly the same level. I then enabled both of them and just for curiosity I swept the delay until I found exactly loudest point using the RTA. I noted the delay value and then I inverted the phase on the sub. I swept the delay again until I found exactly the quietest point (via frequency cancelling) and noted the value. The values I noted using both techniques were exactly the same number! I repeated the same process with the right sub and flying main and again the results were identical but a different value ofcourse...
I then placed the sub and floor main right next to each other and followed your phase technique using pink noise. It was very difficult to tell at which point the frequencies below the crossover point was the smoothest (because they were jumping all over the place) but it appeared to be at about -10 degrees on the sub. I'm curious: does this sound about right or realistic to you?...
Thank you for sharing your technique with me!...:)
Good morning all,
You may have seen this on PSW. If not, interesing thread on subs and placement trade-offs. The 2nd link is in the thread but is a quick reference.
Ya,
Ivan is a crony of Tom Danley...need I say more..If you don't know who he is check out 'Danley Sound' and the \"Matterhorn\".. a 40,000 watt 40 driver speaker he was commissioned to build that would be able to set off avalanches...from a great distance and other \"military\" applications...
He is creator of the Basstech 7 and the Labsub, and all the SPL labs speakers. Interesting cat...
Kev..
Seems like you did well.. what does it sound like now? was there any improvement?
G
Kev..
Seems like you did well.. what does it sound like now? was there any improvement?
G
Gary, It definitely sounds better!... I also experimented with the slight overlap (by one step) verses a slight gap (by one step) on the crossovers... Even though the difference between is very subtle (especially to my ears) I kinda of liked the slight gap... It's difficult to explain but it kinda sounded "cleaner" or "fresher" to me...heck I don't know... Have you ever tried it? Dra?... Does the phase correction I came-up with on the subs sound legit to you?...
Ah but you see my young prankster... I can reverse time and make YOU out to be the fool HA HA HA HA!
oh well I shouldn't post when I'm in a hurry... and I'm always in a hurry.. so see ya....But I digress...
Actually nothing surprises me any more... did you sweep all the way through 180 degrees? And thats where it looked AND sounded best? REMEMBER THIS... the ears ALWAYS win! I don't give a darn what the machine says.. if it sounds wrong it's WRONG!
As for the crossover point... it is seldom/never good to overlap...if your going to do it right it needs to be terminated at the crossover point, or separated by a few, to several's of hz.. I have seen JBL\"s with 50 hz spreads at Hipasses and way more for lo passes... Don't be afraid to experiment.
On a lighter note I (on a whim... because I didn't like the way things sounded last w/e... reset using ONLY my ears and years.... the results were STUNNING! The band.. a group of guys I did for about 10 years... but the last time was 13 years ago! Oui Vei! I'm really dating myself now....suffice it to say it was magic... the night was awesome and the recording... UUFDA... more to follow...
Gadget
Actually nothing surprises me any more... did you sweep all the way through 180 degrees? And thats where it looked AND sounded best? REMEMBER THIS... the ears ALWAYS win! I don't give a darn what the machine says.. if it sounds wrong it's WRONG!... Gadget
Soooo...I guess what I'm hearing from you is that it doesn't sound kosher?... OK give me some idea (a starting point) of what YOU normally end up with?... Maybe I should try it again while listening to music and not doing the pink noise thing?... Hey,...I've been meaning to ask you this for sometime now: what's your favorite Steely Dan song for tuning a system with?...
Another question: If I built a custom dual driver subwoofer cabinet could my amp (EP2500 in bridge-mono, 4-ohms) push these, or would these be better?
Which speaker? I say the first (sens, power, extended low end, and it looks like a speaker).
When you say custom, do you mean custom or that you are going to build them yourself? Gadget has posted several sites that offer free plans for a variety of sub designs. I can't remember if it's this forum or the old one.
Ah yes... this I have seen...EV MAN! we'll talk about that in a minute...Heavens no I wasn't saying that doesn't sound right...I was just trying to indicate that I have seen it anywhere BUT right at -0- or 180 degrees. and also that I'm NOT clairvoyant! Newsflash! I've got ESPN ...but it isn't working! :shock: I was also making sure you had actually swept all the way through... I should have known better...you are very thorough.
These speakers...are they for you? what are the criteria?...portablilty...weight...size...low frequency (and I mean LOW...like 20hz area in groups?....actually I realize you are talking limited power so were talking efficiency then...The cabinet here is the important thing..if you don't have a cabinet designed for that exact speaker, then these would be better (actually almost anything would be) http://www.fane-acoustics.com/public_ht ... ch200L.pdf
I have some of these in the 15 inch with the Colossus 18XB and man do they rock with the NADY 2400.. made in the same plant as the QSC RMX series with just a different case...
If you like purity of sound and low frequency projection AND efficiency, then horn designs are the way to go! The LABsubs are awesome! and there are some good ones that are very cost effective here.. http://www.billfitzmaurice.com/
we have built some of these designs with excellent results.
What I'm getting at is that the cabinet is of utmost importance here...you can't just throw any speaker at any cabinet and expect them to bond... if the speaker and cabinet don't match up you'll have premature speaker failure and poor performance.
Comments
Gadget,...You are correct!... I have a renewed interest in audio and it has become an ADDICTION!... I have found this PA stuff to be much more exciting than the audiophile gadgets (pun) I owned in the 1970s... Heck...I had shelves full of stuff including: Numark EQs, MXR dynamic range expander, Nakamichi Dragon, Yamaha high speed DC amp, linear tracking turntable, Marantz receiver with preamp out, six Advent speakers, etc., etc... And nowadays I just have one of those Bose Lifestyle 35 systems... So this install has been extremely challenging, rewarding, and great fun!... You are absolutely correct in that now I am totally aware of any sound reinforcment, and I listen to it very carefully to compare it to the one I installed... And of course,...the youth center system always blows them away...
Which mixers masters?... The real mixer masters or the ones inside the DriveRack?... Would you please clairify (I mean...spell it out) your "Super Duper Gain Structure Procedure" once you get to the DriveRack... I'm not sure but I could still be under gained here?...
Gary,...question: If you were me...would you just go ahead disable those suckers on the other channels?...
So...I'm assuming by doubling the drivers I would also double the bass response or output?... If so I'm going to keep my eye open for another good set of used VRS18s...
Wolfgong,...Another excellent idea!...:idea:
Wolfgong or Gary,...Just curious: Is there a different response pattern (it's currently flat) that you would suggest I try for DVD movies and/or CD music?...
And...I LOVE IT!
Kevin
Gary,...I forgot to mention: I just returned from praise team practice but I was running behind in getting there... I realized by just HPF-ing everything except the bass and keyboards (drums are acoustic and not miked) that there was a MAJOR IMPROVEMENT in the mix... They practice again this Sunday afternoon before service so I plan on trying some of the other things you suggested...
Once again...I thank you!...:)
Regarding drive rack autoEQ response patterns: I only had time to try response A. It sounded pretty good just for playback.
What you can do is go into the EQWizard and when you get to the step that prompts for a response pattern you can dial through them and see a image of what each pattern looks like in the tiny little screen.
I think the one I used had a dip at about 250Hz and a bump to the left and a rising curve to the right.
I hope this helps. I can't do much more for you right now as I don't have a unit hooked up that I can look at.
Cheers!
I was talking about the masters on the Allen and heath
Set the input volumes on the Driverack just below clipping with the mixer clipping... ABSOLUTELY NO clipping on the outputs...
Amps to clipping, then back off a few DB for headroom...
The typical favorite seems to be the \"C\" curve for rock music... I have stored all of them after I got flat first...It's simple to do with the \"indoor method\"
Leave the limiters on, but kill the auto and if possible the brick walls... if you have sufficient headroom the limiter should never normally hit anyway...
If you set the limiters on the amps you are relegating yourself to only about 1700 watts in bridged mono... let the Driverack do that
It's not quite that simple with speakers.. it's like jets.. two jets isn't twice as loud as one... it takes three... you get the 3db of free gain though... Remember that if you have a 200 watt amp to get twice as loud you would need 10 times that power or 2000 watts.
UUFDA I'm pooped.. good weekend though.. excellent band!
G
Thank you so very much for the valuable information!... I'm heading to the youth center right now to re-check the gain structure because I know that I'm still short of having set-up correctly in the DriveRack... I will also disable the clip limiters on the six PA amplifiers and turn off the \"auto-on\" and \"peak-stop\" artifacts on the other channel limiters inside the DR260... I want to get this done today before the 4:30 praise team practice...
I'll post back later this evening...:)
Thanks!
Kevin
I just looked at sound job for a new beauty salon in Lexington... It looks like a 70.7 volt system will work best for this application... I was able to quote this system (installed) for just under 6K... I quoted using the following items (I only gave descriptions to customer):
1. 12EA ATLAS SOUND FAP42TC COAXIAL CEILING MOUNT SPEAKERS
2. 1EA ATLAS SOUND WMA12-23 WALL MOUNT RACK
3. 1EA TRIPP LITE IBAR12 RACKMOUNT SURGE/SPIKE/NOISE SUPPRESSOR
4. 1EA SIRIUS SRH550 TUNER W/SRH550BK BRACKET KIT
5. 1EA MARANTZ PMD800 AM/FM RACKMOUNT TUNER
6. 1EA DENON DCM-290P RACKMOUNT 5-DISC CD CHANGER
7. 1EA AUDIOSOURCE PRE ONE/A PREAMPLIFIER
8. 1EA ROLLS RA2100B 200WATT 70-VOLT AMPLIFIER
Even though it's an entirely different type of system compared to the youth center I'm pretty excited about the possibility of getting it...:)
Kevin
Are you going to need a zone controller with that?
Just curious, because I have a similar thing in the wings.
I am also using the DR260 for zone control in my famous gym installation.
Cheers!
It's an open station beauty salon so they only want background music that they can easily talk over (imagine that...20 women or so), with no zone control, no volume attenuators (except main system volume) and no voice over paging... Anyways,...it's going to be a pretty simple setup...for now... I've already considered some what-ifs,..and I'm planning ahead to accomodate any foreseeable expansions...:)
Kevin
What is your \"super duper\" way to calculate or determine the best or most accurate timing delay between mains and subs?...:?:
Kevin
Either play a track (or live) of a kick drum hitting at 1 sec intervals or so. Maybe put a gate on it with fast attack and release, and no other effects. When the delay is right it should be loudest and tight.
I have tried using the sample loop on my CD player and find a good kick hit with resonable results. It just time consuming finding the right spot with out too many artifacts. I may make myself a CD when I think to do it and feel in the mood.
Dra
What is your preferred method of setting the delay between your mains and subs?...
Kevin
Dra
First off let me say that there is no way you'll ever get the time alignment perfect...it AIN\"T gonna happen. Whats right at the crossover point isn't necessarily going to be right 20 hz above and below the crossover.. here we should also add that there is also phase to take into consideration...Phase when done properly will always end up somewhere between 0 and 180deg's...never exactly -0- or -180- degrees...(oops! there's those nasty absolutes cropping up again.. I HATE.. OOPS.,. there's another of my pet peeves... but I digress.. as usual...) The \"Ideal\" alignment will be a compromise at best. that said here's a tried and true method thats fairly easy and quick...but \"your mileage may vary...\"
We will assume a 100 hz crossover point for this exercise.. again \"your crossover point may vary\"...One side of the PA running ONLY! copy the settings to the other speaker or use 'linked stereo'. Play a 100 hz tone with your handy dandy signal generator with equal volumes coming from both subs and tops (of the 100 hz tone). Invert the phase of the subs (thats accessible by left clicking on the numbers of the individual outputs at the far right of the GUI. Turn the polarity phase on and if its set at pos... select neg...) sweep the delay of the tops till the 100 hz is almost canceled. Invert the phase of the subs back and see if there is a large dip on either side of the 100 hz... if so you may be exactly 10ms off... Easily checkable...
Now lets talk a bit about phase... this is the way we see if we can balance the sound of the crossover point with the adjacent frequencies. using the RTA play a pink noise signal and note the bands below the 100 hz crossover point. If there are large peaks (or even if not try this) again using the polarity/phase control we spoke of earlier..turn on the module, make sure it's on the normal polarity for your setup and sweep through the phase till the response on the RTA smooths out...this is only as accurate as the resolution of the RTA, and frankly 28 bands is like using BOZO's shoes to try and navigate a mine field... There are RTA's with upwards of 128 sampling points and more...Like the 'True RTA.. a free.. to moderately cheap depending on features RTA...downloadable...thats another discussion..
Thats it.. again there are more accurate ways with TEF and SMAART type alignment tools.. but only a few have the tools, and actually CAN do this properly.
Perhaps Mikey is lurking and would consider chiming in?
Gadget
:arrow: You do realize that we have only barely scratched the surface on this audio stuff.. don't you :?: :shock:
Excellent!... That is an ingenuous way to set the delay using the tools at hand!... It makes practical sense that the delay will cause cancellation of the mains and subs...if they are 180 degrees out-of-phase and timed properly... I love it!...
For my scenario I'm assuming I should follow this procedure for the flying (JRX115i) mains and the subs,...and then repeat it for the floor (JRX125) mains and the subs?...
Also,...for my scenario...would you recommend just a tad of compression (without make-up gain) for our "live program"?... If so,...where should the compressor be inserted in the signal chain and what would be some good preliminary set points?... Do I need or want the Notch Filter in the chain?...
This is the main chain I currently have for the "live program"...
M--->GEQ--->FB--->N---D--->
Sorry for all of the questions...:)
Yep,...I'm just taking baby steps one at a time... I think have the crossovers, gain structure and GEQ pretty well down for now,...so proper delay is next on my long list... I like having a good understanding or being some what confident in one subject before moving-on to the next one... Maybe compression (if you think it could help) and then feedback control are next?...
Dra,...I have read exaclty what you described on another forum somewhere... I hope to realize more punchy bass if I can get the delay(s) half way close to being right...:?
Thanks guys!
Kevin
Glad to see the site back up.
Here's my .01.
To me the notch filter is most useful if you are maxing out your AFS filters and need more. A very little bit of compression might be beneficial. But in your application, could be very beneficial, if the following is true. Does the preacher get overly excited and loud at times? Compression would work great for this, but you'd need to punch it in and out. Now, if the band ever plays background while he speaks, that could be a problem. Auto-gain could also be used while he speaks, if he tends to get soft. Again, would need to be punched in and out.
Assuming......I think I'd lean for compression ahead of AFS. I also think I'd lean for AFS ahead of compression. In other words, do I want to quash potential feedback induced by volume (compressor 1st) or potentially trigger the compressor if feedback starts to occur (AFS 1st). Did that make sense? I'm not sure I undersatood it.
Dra
On one very cloudy day
Yes,...the minister fluctuates allot while he is speaking and at times the vocalist(s) as well... I was kinda hoping to do a mild catch-all or set-n-forget compression if it would add any benefit... I think I'd rather not have any at all...if I would need to toggle it... I want to keep this system simple,...and eventually (regrettably so) I will need to wean myself off of it...:(
Almost sounds like the chicken and the egg mystery...:)
Kevin
Dra
Gary walked me through it as an exercise but afterwards I put everything back to its original state... I hope to start from scratch again in the very near future to get it set-up for good... It really takes two people to do it correctly I think... One person should be moving about the stage with the microphone held in different directions while the other person is selecting the channels, adjusting the gain, watching the AFS to catch the ringing frequencies, and setting the PEQs...
Kevin
Dra
Gadget,...Thank you for another enlightening conversation!...:brown nose:... They still haven't got an emoticon for that...
It is definately going to take two people to set the delay as you suggested...one to stand between the sub and main and the other to sweep the delay... The subs and mains are about 10-12FT apart... The floor mains are about 8-10" out from the wall but directly under the flying mains... The subs are in the corners and facing-out on the diagonal... Sooo...here's a stupid question: Should the person that is listening for the cancellation point be located directly in front and centered between the sub and main being tested?...or should they be directly centered between the two in both directions?...or should they be directly centered between the two while dancing in circles with a beheaded chicken?...
Also,...I have read that some people like to set a small gap between the crossover points instead of a small overlap... They claim it gives them more of a "studio sound"... Since you been around-the-block a few times I would like your thoughts on this...
Kevin
I finally got back to the youth area today to set-up the delays between the mains and sub. Your technique worked beautifully! Instead of using my poor hearing I used the RTA mic and placed directly between the mains and sub. I first muted everything but the right sub and noted my volume level with RTA at the crossover point tone. I then muted the sub and enabled the right floor main. I used the amp attenuator and brought it up to exactly the same level. I then enabled both of them and just for curiosity I swept the delay until I found exactly loudest point using the RTA. I noted the delay value and then I inverted the phase on the sub. I swept the delay again until I found exactly the quietest point (via frequency cancelling) and noted the value. The values I noted using both techniques were exactly the same number! I repeated the same process with the right sub and flying main and again the results were identical but a different value ofcourse...
I then placed the sub and floor main right next to each other and followed your phase technique using pink noise. It was very difficult to tell at which point the frequencies below the crossover point was the smoothest (because they were jumping all over the place) but it appeared to be at about -10 degrees on the sub. I'm curious: does this sound about right or realistic to you?...
Thank you for sharing your technique with me!...:)
Kevin
You may have seen this on PSW. If not, interesing thread on subs and placement trade-offs. The 2nd link is in the thread but is a quick reference.
http://srforums.prosoundweb.com/index.p ... 126/0/0/0/
http://www.campuspa.com/images/subarray/
Enjoy,
Dra
Wow!... That's some killer info!... I copied Ivan Beaver's post to a word document for future reference...:)
Thank you!
Kevin
Ivan is a crony of Tom Danley...need I say more..If you don't know who he is check out 'Danley Sound' and the \"Matterhorn\".. a 40,000 watt 40 driver speaker he was commissioned to build that would be able to set off avalanches...from a great distance and other \"military\" applications...
He is creator of the Basstech 7 and the Labsub, and all the SPL labs speakers. Interesting cat...
Kev..
Seems like you did well.. what does it sound like now? was there any improvement?
G
It would be more impressive if he were a crony.... and not a vegetable.
Sorry, that was too easy.
Dra
Dra
Kevin
oh well I shouldn't post when I'm in a hurry... and I'm always in a hurry.. so see ya....But I digress...
Actually nothing surprises me any more... did you sweep all the way through 180 degrees? And thats where it looked AND sounded best? REMEMBER THIS... the ears ALWAYS win! I don't give a darn what the machine says.. if it sounds wrong it's WRONG!
As for the crossover point... it is seldom/never good to overlap...if your going to do it right it needs to be terminated at the crossover point, or separated by a few, to several's of hz.. I have seen JBL\"s with 50 hz spreads at Hipasses and way more for lo passes... Don't be afraid to experiment.
On a lighter note I (on a whim... because I didn't like the way things sounded last w/e... reset using ONLY my ears and years.... the results were STUNNING! The band.. a group of guys I did for about 10 years... but the last time was 13 years ago! Oui Vei! I'm really dating myself now....suffice it to say it was magic... the night was awesome and the recording... UUFDA... more to follow...
Gadget
Another question: If I built a custom dual driver subwoofer cabinet could my amp (EP2500 in bridge-mono, 4-ohms) push these, or would these be better?
Kevin
When you say custom, do you mean custom or that you are going to build them yourself? Gadget has posted several sites that offer free plans for a variety of sub designs. I can't remember if it's this forum or the old one.
Dra
These speakers...are they for you? what are the criteria?...portablilty...weight...size...low frequency (and I mean LOW...like 20hz area in groups?....actually I realize you are talking limited power so were talking efficiency then...The cabinet here is the important thing..if you don't have a cabinet designed for that exact speaker, then these would be better (actually almost anything would be)
http://www.fane-acoustics.com/public_ht ... ch200L.pdf
I have some of these in the 15 inch with the Colossus 18XB and man do they rock with the NADY 2400.. made in the same plant as the QSC RMX series with just a different case...
If you like purity of sound and low frequency projection AND efficiency, then horn designs are the way to go! The LABsubs are awesome! and there are some good ones that are very cost effective here..
http://www.billfitzmaurice.com/
we have built some of these designs with excellent results.
What I'm getting at is that the cabinet is of utmost importance here...you can't just throw any speaker at any cabinet and expect them to bond... if the speaker and cabinet don't match up you'll have premature speaker failure and poor performance.
So what are you thinking here?
G