Sorry i presumed u knew what bfm stood for. Bill Fitzmaurice he has a whole forum devoted to his stuff. It gets mixed reviews tho. So im not set on anything at this point. And im back to phone internet again after my ISP decided to be jerks. I wan to have a play on horn resp soon and see how certain cabs sim vs others.
Klampy.....
So.....here is where you have to decide if you want tight impactful kick drum / bass sound, or if you just want loud flabby sound?
What is the key to tight sound? Well, since I'm extremely stubborn and have no problem repeating myself, again, the answer to this is *time alignment*. I cannot stress this enough - anybody who is running a large multi-way PA system with horns (and who knows what they are doing), has a processor that is capable of time correction. This is used to time align the outputs of your various speaker, which results in something approaching correct *impulse response*.
What is a Kick Drum sound? Its a sound *impulse*, a bunch of sound frequencies occuring at the same time which result in you hearing a kick drum. If the 80hz part (coming out of your ss15's) of the kick sound arrives 5ms behind the 200hz part (from your mains) of the kick sound..........well, it's going to have much less impact and overall sound like wooly crap.
Here is additional discussion on time correction, group delay, impulse response etc:
lilmike's Shiva X2 Tapped Horn (note the graph scales)
http://www.diyaudio.com/forums/subwoofers/190635-th-18-flat-35hz-xoc1s-design-4.html#post2604579
http://forum.speakerplans.com/show-off-your-sound-systempart-2_topic38351_page361.html
FOH online | A Realistic Approach to Subwoofer Time Alignment
Live Sound International | Tech Talk: How to correctly get loudspeaker drivers in sync
You NEED one of these, you NEED to delay your tops to match the delay in your subs:
Behringer: ULTRA-DRIVE PRO DCX2496
Once you do this, you can start to seriously consider if you need more output from your mains in the mid-bass.
I would also be concerned with the group delay peak around 150hz in the SS15, that can't be playing nice......
So.....here is where you have to decide if you want tight impactful kick drum / bass sound, or if you just want loud flabby sound?
What is the key to tight sound? Well, since I'm extremely stubborn and have no problem repeating myself, again, the answer to this is *time alignment*. I cannot stress this enough - anybody who is running a large multi-way PA system with horns (and who knows what they are doing), has a processor that is capable of time correction. This is used to time align the outputs of your various speaker, which results in something approaching correct *impulse response*.
What is a Kick Drum sound? Its a sound *impulse*, a bunch of sound frequencies occuring at the same time which result in you hearing a kick drum. If the 80hz part (coming out of your ss15's) of the kick sound arrives 5ms behind the 200hz part (from your mains) of the kick sound..........well, it's going to have much less impact and overall sound like wooly crap.
Here is additional discussion on time correction, group delay, impulse response etc:
lilmike's Shiva X2 Tapped Horn (note the graph scales)
http://www.diyaudio.com/forums/subwoofers/190635-th-18-flat-35hz-xoc1s-design-4.html#post2604579
http://forum.speakerplans.com/show-off-your-sound-systempart-2_topic38351_page361.html
FOH online | A Realistic Approach to Subwoofer Time Alignment
Live Sound International | Tech Talk: How to correctly get loudspeaker drivers in sync
You NEED one of these, you NEED to delay your tops to match the delay in your subs:
Behringer: ULTRA-DRIVE PRO DCX2496
Once you do this, you can start to seriously consider if you need more output from your mains in the mid-bass.
I would also be concerned with the group delay peak around 150hz in the SS15, that can't be playing nice......
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i have a MiniDSP on its way. which i believe has delay settings within. beyond this, even on their own, the deltas just dont have the punch when talking about open air use. hence my desire for more output. the cabs theyre in atm, are reflex tuned to 80hz. i still want to horn load them one way or another, but i completely understand the time alignment so will be sure to try this first before rebuilding cabs.
current cabs need to be modified to fit the D220ti inside so this is happening first.
current cabs need to be modified to fit the D220ti inside so this is happening first.
Hi Klampy
Good to see that you are upgrading your HF drivers and are moving to a digital crossover.
Doubling up on your Delta 12 mids in a QB5 cab using the digital crossover to set the EQ would get you a lot closer to your ideal with minimal expense.
By the way what is your front end that you use with your PA?
Looking at your pic in post 67 do I see a laptop on a folding table?
Have you got a mixer as well hidden in behind there.
Simple tweeks to the front end of your system could make a significant difference - You are building a fairly awesome PA system. Crap in crap out!
Want to try an experiment? Just put the source components on a better support! (One that does not vibrate)
Good to see that you are upgrading your HF drivers and are moving to a digital crossover.
Doubling up on your Delta 12 mids in a QB5 cab using the digital crossover to set the EQ would get you a lot closer to your ideal with minimal expense.
By the way what is your front end that you use with your PA?
Looking at your pic in post 67 do I see a laptop on a folding table?
Have you got a mixer as well hidden in behind there.
Simple tweeks to the front end of your system could make a significant difference - You are building a fairly awesome PA system. Crap in crap out!
Want to try an experiment? Just put the source components on a better support! (One that does not vibrate)
Thanks for the kind words Xoc. front end is my acer laptop witha denon DNMC6000 digital mixer.
As far as sound output goes its all done by asio drivers. Im not sure how much adjustment i hace on the output side. Ill try what u said regarding the table.
Turbodawg. I read the thread u linked. Enough said. Cant wait to get my dsp.
As far as sound output goes its all done by asio drivers. Im not sure how much adjustment i hace on the output side. Ill try what u said regarding the table.
Turbodawg. I read the thread u linked. Enough said. Cant wait to get my dsp.
You'll be getting less out the ports, and restricting ventilation around the magnet (if you're really hammering them), so I'd advise against it for high-power use.
Chris
ok, im just waiting on grilles now to call them done, but i glued a layer of accoustic(eggcarton) foam to the back, lower 1/3 of the cab. and also wrapped the tweeter horn in polycroft wadding. along with the new crossovers and new D220ti CD they sound very much full and clean. im yet to crank them up, but i can already hear that they sound better to me. im expecting that as the volume climbs, they will get more and more impressive until their SPL limit of course.
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