I might try some passive tapering but I have found no one who has talked about the proper way to do it. No diagrams etc. Is it as simple as series resistors after the crossover to the various speakers???
The other question is in the wiring of the speakers. I can do the math to get the overall resistance the amp sees, but does the group of series speakers with different resistance behave differently when paralleled. For example you have a 2 4 ohm series for a total of 8 ohms you also have 4 4 ohm series for 16 ohms. You parallel 8 ohm group with the 16 ohm group for a total of 5.33 ohms. So my question is does the 8 ohm group play louder than the 16 ohm group. Is this one of the passive ways to power taper?
I could use some help thanks.
Tom
Power shading a floor to ceiling line doesn't have the same effect as it does on shorter arrays and is considered by most of the well know line array experts like Dave Smith and Jim Griffin to not be a good idea.
It makes no sense to me when you are using a big ribbon for the HF element.
There is an old thread here which had similar sentiments although I don't agree with Jim that a full range array is not as good as a two way without more specifics on the set up used.
Line Array Power Tapering?
It makes no sense to me when you are using a big ribbon for the HF element.
There is an old thread here which had similar sentiments although I don't agree with Jim that a full range array is not as good as a two way without more specifics on the set up used.
Line Array Power Tapering?
I am using a large ribbon because it is part of my main speakers. It is a newform research r45 and will borrow it to try with a line array. Others have built line arrays with these ribbons so I thought I would give it try.
Read the link and they do not address or explain how they are power tapering. So to my original question if a 8 ohm group is louder than a 16 ohm group? And how are they doing the the tapering passively ( If it can be done passively)
Thanks Tom
Read the link and they do not address or explain how they are power tapering. So to my original question if a 8 ohm group is louder than a 16 ohm group? And how are they doing the the tapering passively ( If it can be done passively)
Thanks Tom
As you can read in my posts on tapering I usually suggest less tapering than others. But tapering can be effective for some applications as I explain in my NFLAWP at:
http://www.audioroundtable.com/misc/nflawp.pdf
In this paper I have an example of passive tapering in which I use driver connections in parallel and series methods which create groups that have different impedances. Hence, I favor power tapering which is lossless and uses no resistors.
I also include calculations how to compute the SPL for various groups of drivers and different impedances.
Power tapering is most effective with cone drivers as they have overlapping power dispersion when arrayed. Ribbon drivers typically radiate such that their vertical plane sound fields may not overlap--specifically vs. frequency. Ribbons tend to radiate such that their vertical dispersion is more limited than their horizontal dispersion. In fact ribbons radiate such that their vertical plane dispersion trends to the ribbon aperture height at their highest frequencies.
fluid would appreciate that I currently have a full range driver line array in the design stage. I'll reserve the right to change my opinion about full range arrays once I hear the new design.
http://www.audioroundtable.com/misc/nflawp.pdf
In this paper I have an example of passive tapering in which I use driver connections in parallel and series methods which create groups that have different impedances. Hence, I favor power tapering which is lossless and uses no resistors.
I also include calculations how to compute the SPL for various groups of drivers and different impedances.
Power tapering is most effective with cone drivers as they have overlapping power dispersion when arrayed. Ribbon drivers typically radiate such that their vertical plane sound fields may not overlap--specifically vs. frequency. Ribbons tend to radiate such that their vertical dispersion is more limited than their horizontal dispersion. In fact ribbons radiate such that their vertical plane dispersion trends to the ribbon aperture height at their highest frequencies.
fluid would appreciate that I currently have a full range driver line array in the design stage. I'll reserve the right to change my opinion about full range arrays once I hear the new design.
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I don't know anything about that ribbon, but it in pictures it looks like it is three smaller units combined.
The point of the link was to say don't power taper a floor to ceiling array 🙂
I don't have any practical experience of it so I can't offer you anything on the how.
Why do you want to, what do you think it will do? You aren't planning on building a Bessel Array or a CBT so I don't understand the reason for tapering 😕
I would be interested to hear more about the design you have in the works, I hope it works well for you. Line arrays in general are a little thin on the ground and people that have practical experience with more than one type are even rarer.
From what you wrote before it was the combing that you were most concerned about. For myself I am totally satisfied that it's a red herring in practice. With a long line of small enough drivers and a reasonable listening distance you can't hear it, and it even becomes hard to see in measurements in room at 2 to 3m other than above 15K (Outdoors is easier to see).
Digital processing can be very useful in getting an improvement if you can add that into your options. Basic PEQ can wrangle it into line but I do prefer mine with DRC.
Get yourself Bill Waslo's X-Sim program and model the scheme you like to use with it. It will give you an insight in how it all works together. It can show you how many watt each driver gets etc.
For instance, 25 drivers, 5 drivers parallel, 5x series compared to 25 drivers 5 drivers series, 5x parallel:
5 drivers parallel:
5 drivers in series:
As we see here it does matter how everything gets wired. My arrays are wired according to the second scheme, but if time permits I'd like to try out the first.
Your case can be modeled too, use the driver's impedance curves.
Very interesting 🙂.
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Quote:
Originally Posted by Jim Griffin:
"fluid would appreciate that I currently have a full range driver line array in the design stage. I'll reserve the right to change my opinion about full range arrays once I hear the new design."
I'd like to see Jim start a build thread so we newbies could learn from yet another experienced 'phile. I'm strongly considering the PE CBT kit, but might be swayed to DIY something that would be better.
Originally Posted by Jim Griffin:
"fluid would appreciate that I currently have a full range driver line array in the design stage. I'll reserve the right to change my opinion about full range arrays once I hear the new design."
I'd like to see Jim start a build thread so we newbies could learn from yet another experienced 'phile. I'm strongly considering the PE CBT kit, but might be swayed to DIY something that would be better.
HankF,
If the OP does not mind going a little off topic...
The CBT concept is a very clever concept, like any other it requires certain things to perform it's best. If you look around the array conversations here there have been a few measurements floating around that really show it's potential.
What I want to say is: pick the one that can work best in/with your room. Figure out how you can make the speaker + room work together. That's an area where we as DIY can get the most benefit.
If the OP does not mind going a little off topic...
The CBT concept is a very clever concept, like any other it requires certain things to perform it's best. If you look around the array conversations here there have been a few measurements floating around that really show it's potential.
What I want to say is: pick the one that can work best in/with your room. Figure out how you can make the speaker + room work together. That's an area where we as DIY can get the most benefit.
Jim: Thanks for your message. I replied.
wesayso: Understand the room interaction thing. My room is huge: 10 to 15 ft+ sloped ceiling height, room open to kitchen, hall, and upstairs loft - LOTS of cubic feet and not symmetrical. My Acoustat Model 3's are too wide - cover up part of my 134" projection screen. Narrow line array's would be perfect fit.
wesayso: Understand the room interaction thing. My room is huge: 10 to 15 ft+ sloped ceiling height, room open to kitchen, hall, and upstairs loft - LOTS of cubic feet and not symmetrical. My Acoustat Model 3's are too wide - cover up part of my 134" projection screen. Narrow line array's would be perfect fit.
I built one about 10 years ago that Jim commented on over on PE's techexpress forum when I got into it with Rick Craig. Jim basically affirmed that I had followed his procedure.
It worked great until I had to move it 600 miles on a moving truck. I've not had the time to trouble shoot whether one of the hundreds of welds on the Tweeter array of 64 Dayton ND20FA, came lose or whether my Rane AC23 died in the trip.
Mine was/is active crossed tri-amped, with a separate tube enclosure for each mid range and a 12 inch woofer for each channel crossed at near sub levels. Each channel has a 12 inch DVC 15mm xmax woofer, 17 3.5 inch midranges, and 32 dome tweeters. It was awesome.
I still have all the pictures and all the research.
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I built one about 10 years ago that Jim commented on over on PE's techexpress forum when I got into it with Rick Craig. Jim basically affirmed that I had followed his procedure.
It worked great until I had to move it 600 miles on a moving truck. I've not had the time to trouble shoot whether one of the hundreds of welds on the Tweeter array of 64 Dayton ND20FA, came lose or whether my Rane AC23 died in the trip.
Mine was/is active crossed tri-amped, with a separate tube enclosure for each mid range and a 12 inch woofer crossed at near sub levels.
I still have all the pictures and all the research.
I'm building a new one for downstairs. It has to fit more easily in the downstairs living/din/kitchen open concept space. The mid range will go 70% of the ceiling to floor to make the coupling. The tweeters will be planars. There will be an 8 inch mid woofer, and a 12 inch sub woofer in a sealed tube equalized to about 27 hz F3. And like before, I will be using active crosses with 8 separate amps. the six amp channels for the tweet/mid/mid woof will be 100 watts rms per channel. The sub will be using a big heavy amp that puts out 375 watts per channel, necessary for equalizing into the deep bass range.
And once again, all speakers will have their own individual cylindrical tube enclosures packed with fiberglass to 4 lb/cu ft, with wood rods in the fiberglass, to eliminate 98 of the back wave, and remove all even order harmonics in the back wave.
Interesting enclosure concept. I assume this will be your primo speaker pair, given the total cost. All the best to you!
Hmm total cost? Haven't really thought about it after the WAF told me I could do it.
Rane 6 150 watts rms/channel amp from ebay : $90
Onkyo Preamp w/ remote control(got into turning it down from the couch): $110 ebay
Already own the 375 rms wt/ch sub amp.
Already own the DOD equalizer
Already own the two 8 inch mid woofs
Already own the two 12 inch subs
two 4 way mono Behringer electronic crossover units: $260
40- Dayton Audio CE Series CE65W-8 2-1/2" 8 Ohms. $5.20 each: $208,
14- Dayton Audio PTMini-6 Planar Tweeter 6 Ohm: $156
various box and materials: $30
various connection cables: $50
Total: $904---spread over about 5 months of purchasing, so as not to freak out the WAF: at about $180 a month.
So maybe..... yes. Or maybe I just won't do it at all.
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Good plan
A number of years of tinkering with line-arrays has taught me that individual driver enclosures are very important, maybe essential. Building line arrays in boxes without this criterion is daunting., with it, downright intimidating. Using tubes will save a lot of work.
I really like the approach. Killer system for an additional outlay of $900 - that's the real DIY ethic.
I don't know the Behringer units you are considering. I used a DCX2496 for many years until the limitation of 6 outs finally kicked me to go MiniDSP. The MiniDSP 10 x 10 (8 x 8 board) had very clearly superior audio to Behringer, most noticeable in the bass. It will force your budget up a notch. Worth consideration. On the other hand the Behringer units you are considering may be a wholly different animal than the DCX2496.
A number of years of tinkering with line-arrays has taught me that individual driver enclosures are very important, maybe essential. Building line arrays in boxes without this criterion is daunting., with it, downright intimidating. Using tubes will save a lot of work.
I really like the approach. Killer system for an additional outlay of $900 - that's the real DIY ethic.
I don't know the Behringer units you are considering. I used a DCX2496 for many years until the limitation of 6 outs finally kicked me to go MiniDSP. The MiniDSP 10 x 10 (8 x 8 board) had very clearly superior audio to Behringer, most noticeable in the bass. It will force your budget up a notch. Worth consideration. On the other hand the Behringer units you are considering may be a wholly different animal than the DCX2496.
Only the CX-2310 gives me what I need. I will need two of them because I need a 3 way with a sub output.
I will have 2 subs running equalized 27-about 100 in sealed tube. The digital versions either require a computer to organize it(which I'm sure I could use my MacBook Pro) for, or they are too complicated for me in my old age and also have stuff I don't need, or they don't have dual sub outputs, or it adds more money that I really don't need to get a terrific unbeatable system. I'm always the minimalist. Get what I need to do the job properly, but not more.
For example, it is my philosophy that crossing in the middle of the Fletcher-Munsson sensitive range is counter productive to lowered distortion and open ness in the sound. And so in a line array this means that it would be best to cross at about 550 and 5000 which is a little more than 3 octaves. To do that without comb means that the mid has to be about 2.5 inches or smaller. And to do it without stress to the speaker , and to have a line long enough to couple with the ceiling and floor means at least 20 of them per channel.
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