Ok, so now I've finished the ghetto sub at the workshop I'm onto my next project - a sub that is going into a 6500sqf warehouse. It doesn't have to be insanely loud or balanced, but needs to have decent response from 40-120Hz. The box will be placed in a corner, if that changes the response.
I plan on using some 10" Peerless XLS subs that I have lying around. Specs are as follows:
Le = 0.844mH
Re = 2.7Ohm
Re+Rs= 49Ohm
Rc = 18.15
Fs = 38hz
Fl = 29hz
Fh = 48hz
Qms = 8.52
Qes = 0.497
Qts = 0.469
Sd = 353cm^2
Dd = 21.2cm
Cms = 359.744 um/N
Vas = 63.651 litre
Bl = 7.954 T*m
Ref Efficiency = 0.678%
SPL = 90.46 Db/W/m
Now, I have a very limited budget that I am working with, so using these subs is ideal as they cost me next to nothing. I have a few hundred put aside to buy a (second hand) amplifier, so that side of things can come in the future. Guessing I'd end up with somewhere in the realms of 400Wrms stereo. I can easily build a suitable active LPF/subsonic filter.
Basically, I have absolutely no idea what to build. There are no size limitations and I have a fully equipped wood workshop to use (as well as 18mm ply).
*I've had a little bit of a play around with hornresp but couldn't get anything that even looked usable from it
*I've had a look at some of the Decware designs, but was turned off purchasing plans as I've been told they lack a lot of detail that's needed.
*I've modeled some regular ported and sealed boxes, but don't know if they'd have enough volume for such a large area short of hooking multiple boxes up together.
If you were in this situation, what would you build? I don't mind if the thing comes in weighing 400lbs, as once it's in place it won't be moved.
I plan on using some 10" Peerless XLS subs that I have lying around. Specs are as follows:
Le = 0.844mH
Re = 2.7Ohm
Re+Rs= 49Ohm
Rc = 18.15
Fs = 38hz
Fl = 29hz
Fh = 48hz
Qms = 8.52
Qes = 0.497
Qts = 0.469
Sd = 353cm^2
Dd = 21.2cm
Cms = 359.744 um/N
Vas = 63.651 litre
Bl = 7.954 T*m
Ref Efficiency = 0.678%
SPL = 90.46 Db/W/m
Now, I have a very limited budget that I am working with, so using these subs is ideal as they cost me next to nothing. I have a few hundred put aside to buy a (second hand) amplifier, so that side of things can come in the future. Guessing I'd end up with somewhere in the realms of 400Wrms stereo. I can easily build a suitable active LPF/subsonic filter.
Basically, I have absolutely no idea what to build. There are no size limitations and I have a fully equipped wood workshop to use (as well as 18mm ply).
*I've had a little bit of a play around with hornresp but couldn't get anything that even looked usable from it
*I've had a look at some of the Decware designs, but was turned off purchasing plans as I've been told they lack a lot of detail that's needed.
*I've modeled some regular ported and sealed boxes, but don't know if they'd have enough volume for such a large area short of hooking multiple boxes up together.
If you were in this situation, what would you build? I don't mind if the thing comes in weighing 400lbs, as once it's in place it won't be moved.
If you really truly mean that I'd be happy to do a sim for you. But I have a feeling you don't really mean that.
All I need is the size limitation (per cab and total size with multiple cabs) and driver xmax and the amount of drivers that you have.
For the most part all the Decware stuff is pure junk. Some of their stuff will work ok with a limited selection of drivers but if you can't simulate it first you shouldn't build it. And their notion that their stuff will work with a wide variety of drivers is pure marketing.
I did a quick sim just out of curiosity. I assumed you have 10 drivers and are ok with 2300 liters total, that can be broken up into 5 cabs with dual drivers or 10 cabs with single drivers.
I assumed 150 watts RMS power handling capability and somewhere between 12.5 and 15 mm xmax which is fairly typical for this kind of driver.
I used your requested 40 hz low knee, although personally I'd go lower.
This is shown with 1500 watts total so most music should be just fine at this power level with minimal or no power compression. And excursion is fine at this power level even without a high pass filter.
This is 2 pi (open field) response. If you have boundary reinforcement from a single wall or a corner you could gain as much as 6 - 12 db on top of this (assuming infinitely rigid boundaries and perfect reflections).
What more could you ask for? If you say smaller size or fewer drivers I'm not really interested in helping further.
I assumed 150 watts RMS power handling capability and somewhere between 12.5 and 15 mm xmax which is fairly typical for this kind of driver.
I used your requested 40 hz low knee, although personally I'd go lower.
This is shown with 1500 watts total so most music should be just fine at this power level with minimal or no power compression. And excursion is fine at this power level even without a high pass filter.
This is 2 pi (open field) response. If you have boundary reinforcement from a single wall or a corner you could gain as much as 6 - 12 db on top of this (assuming infinitely rigid boundaries and perfect reflections).
What more could you ask for? If you say smaller size or fewer drivers I'm not really interested in helping further.
A 40 hz low knee would cause the subs to puke with the music I like but a 27 hz low knee would cover most music. So let's go lower and go bigger or sit at home sucking our thumb.
This is a 27 hz horn in about 7660 liters with 24 drivers (you said you had 80 drivers and unlimited space so this shouldn't be a problem). You can break this down into 1, 2, 4, 6, 12 or 24 modular boxes.
This is shown with only 2000 watts (83 watts per driver) so you could run it like this and have no need for a high pass filter or you could increase the power several times and get a lot more peak spl but you would need a high pass filter in that case.
Or you could increase the number of drivers in a horn like this, add more power and blow the roof off. It's up to you.
This is a 27 hz horn in about 7660 liters with 24 drivers (you said you had 80 drivers and unlimited space so this shouldn't be a problem). You can break this down into 1, 2, 4, 6, 12 or 24 modular boxes.
This is shown with only 2000 watts (83 watts per driver) so you could run it like this and have no need for a high pass filter or you could increase the power several times and get a lot more peak spl but you would need a high pass filter in that case.
Or you could increase the number of drivers in a horn like this, add more power and blow the roof off. It's up to you.
I haven't grabbed an amp yet. Going off what I've seen within my budget there will be ~800-1000wrms available though.
2000L in total size? I've not really been given an upper limit but it has to unfortunately be slightly sensible. There's only around 600wrms for main speakers so I don't want to massively overpower that.
While I have a heap of drivers, I'd prefer to only use 4-6. As awesome as more would be, it's probably overkill and extra complexity I don't really need. Current drivers are stated at 12.5mm xmax and meant to be 250wrms.
Size is ok, I'd prefer just not to eat up so many drivers in what will be a ***** and giggles project. Thankyou very much for all the work you've done so far though if you're not interested in helping further.
What did I read?
"If you can't simulate it you shouldn't build it"
How will there be any progress?
If you can't simulate it you "should" build it. That's only my opinion.
Besides many things may look good on paper.
And sound mediocre.
It's the relentless perseverance and passion that drives new ideas.
Maybe you can't simulate it because it hasn't been invented yet. And the software doesn't account for many, many things. It's just a general model.
"If you can't simulate it you shouldn't build it"
How will there be any progress?
If you can't simulate it you "should" build it. That's only my opinion.
Besides many things may look good on paper.
And sound mediocre.
It's the relentless perseverance and passion that drives new ideas.
Maybe you can't simulate it because it hasn't been invented yet. And the software doesn't account for many, many things. It's just a general model.
You said you had a few hundred budgeted for an amp. No need to go used or low power. This amp is more than enough to power all 80 of your drivers at once and it's about $1000 delivered to your door.
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"Sensible" is whatever you think it is. If you get good mains with upwards of 100 db sensitivity and high power handling they could keep up with a sub like these pretty easily, especially since most people prefer the bass to be boosted upwards of 10 db over the midrange.
4 - 6 ten inch drivers isn't going to do much bass in a warehouse. And 4 - 6 ten inch drivers in 400 liters total is your average boring run of the mill design, there's plenty of existing info on ported box and tapped horn design. If you search for the driver model you will probably find existing plans for this driver.
With your resources (80 drivers) and unlimited space this sounded like it might be unique and fun. But hey, good luck and have fun with it.
There hasn't been much progress in the last 100 years except in materials. Acoustic theory was well understood a LONG time ago.
While a sim can't tell you how anything will sound, it can tell you almost exactly how it will perform in every category except subjective preference. While it's true that sims can't account for every aspect, the things that are not considered are well known and the impact they will have on the physical product is well understood.
And there's very few things that cannot be simulated. Your creation can easily be simulated, if you could measure the t/s parameters of your conjoined iso unit. And if you did simulate it you would find that while it may be subjectively pleasant sounding, it doesn't perform very well in terms of max spl or efficiency. There are other enclosure designs for the same drivers that would provide much more output and also be subjectively pleasing. So while it's nice that you've created something you like by pure luck, please respect the fact that you can get a lot further a lot faster if you understand the science and simulate the potential results.
For the most part, if your sims don't match your measurements you are doing something wrong. They really are that accurate if done properly.
Imagine what the jet industry would be like today if they didn't simulate almost every aspect of their products. There would be a lot of death and twisted metal on the ground and not much up in the sky. There is a science to this stuff and while you might get lucky sometimes going by intuition alone you are far more likely to succeed by taking advantage of the vast knowledge and resources that are readily available.
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Unfortunately there's a big difference between a few hundred and ~$1200AUD.
While I do have 80 drivers, most of them are earmarked for other projects that actually earn money. This is just something for a bit of fun, as much as I'd love to use them all I just can't.
Again, thanks for your help and input.
Technically 12 hundred IS a few hundred but I digress.
If you look at Behringer products you should be able to get something with 2000 watts or so for half that much or less, probably much less in the used market. If you want to stick with premium brand names you will indeed be limited to used products and low power but that's a choice, not the only option.
If you look at Behringer products you should be able to get something with 2000 watts or so for half that much or less, probably much less in the used market. If you want to stick with premium brand names you will indeed be limited to used products and low power but that's a choice, not the only option.
Let's continue this in your thread then. I'd be happy to sim it. But you need to measure the t/s parameters of your conjoined unit, they WILL NOT be the same as a regular iso unit because you've added a bunch of mass.
It's only literally off the charts until you change the range of the charts. Although I don't have WinISD currently I'd be pretty surprised if you couldn't change the range to view up to 1000 db. So nothing is really off the charts. You can change the range in all the WinISD graphs.
I guarantee if you measure the t/s parameters and give me accurate enclosure dimensions and you measure it properly outside away from reflective boundaries with accurate equipment, my sim will match your measurement.
I meant no disrespect although there is obviously a reason something can't be simulated.
As far as personal preference of sound, I prefer tubes. But they have a much higher harmonic distortion than SS.and horible efficiency. In a simulation tubes would never have been considered and thus never been made.
I do agree with your view on areospace. You obviously know much about sound but if very little has changed in the last 50 years. I'll eat my hat.
As far as personal preference of sound, I prefer tubes. But they have a much higher harmonic distortion than SS.and horible efficiency. In a simulation tubes would never have been considered and thus never been made.
I do agree with your view on areospace. You obviously know much about sound but if very little has changed in the last 50 years. I'll eat my hat.
What is it that you think can't be simulated? Akabak can simulate almost anything you can dream up. Any shape, any size, almost limitless complexity. And it's over 20 years old. The math behind it is MUCH older, many decades older.
You prefer ketchup or barbeque sauce?
While things have changed in some areas, the science of ACOUSTICAL ENCLOSURE DESIGN has made almost no progress in well over 50 years. The math has been well understood for horns (MOST of the common flare types), OB, IB, sealed boxes, transmission lines, ported boxes, and most other things. Danley did come up with a clever variant on the TL recently, targeting a very specific calculated benefit, but other than that it's been pretty quiet. Even with the tapped horn, the enclosure type didn't change (it's still a transmission line) the acoustic theory didn't change, an existing simulator (Akabak) was able to predict it's performance very accurately because physics certainly has not changed. What did change was the intent of using a clever driver position to fill in a natural transmission line null, that's it. And that's fairly big news considering that really nothing else truly innovative has come along in decades.
The general public was largely unaware of the math behind this stuff but it was out there. And with the advent of simulators (over 20 years ago for Akabak and over 40 years ago for Hornresp), the general public doesn't even need to know ANY math.
The main advances have been in materials that allow stuff like transistors and very high temperature adhesives to be invented and manufactured. But with respect to box design there's very little new under the sun.
If you can calculate how a wave behaves in a closed and/or open ended duct of constant or varying cross sectional area, you basically have the math to program a relatively fully featured simulator. And that math has been around for about a century. And since even the alignments that may not have been invented yet (if this is even a possibility) need to follow the rules of physics, the current simulators are ready and waiting for them to be invented since they are already fully capable of simulating the effect of waves in any shape enclosure you can imagine.
Tube sound is ALL about distortion (and high output impedance causing bloated bass I think?), and since it's primarily even order distortion it sounds great. You can easily emulate the tube sound and play it through transistors and get the sound you like with the efficiency of SS.
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I don't want you to eat your hat.
What I would like to do is show you how to use your simulator properly and discuss the science behind what you built. But only if you are interested. Changing the range of the graphs in WinISD is easy enough for both axes so let's simulate it properly and compare it to something else.
If you want to continue let's do it in your thread.
What I would like to do is show you how to use your simulator properly and discuss the science behind what you built. But only if you are interested. Changing the range of the graphs in WinISD is easy enough for both axes so let's simulate it properly and compare it to something else.
If you want to continue let's do it in your thread.
That would be excellent.
I appreciate it. Thank you.
I know I'm swapping efficiency for low end.
But I really don't understand what I'm looking at.
I know what I hear. Deeper lows than anything I've heard. But I need a pretty big amp to drive them.
Hey dreadnought if you are looking for SPL at 40hz
This is not your best choice. But if you want 20 hz minus? You should check it out.
Just a guy, that's very kind of you, I hope it's no bother and you find it somewhat interesting.
I'll post the specs of the Orion and draw something up I might have to use pencil and paper if Autocad is misbehaving.
I appreciate it. Thank you.
I know I'm swapping efficiency for low end.
But I really don't understand what I'm looking at.
I know what I hear. Deeper lows than anything I've heard. But I need a pretty big amp to drive them.
Hey dreadnought if you are looking for SPL at 40hz
This is not your best choice. But if you want 20 hz minus? You should check it out.
Just a guy, that's very kind of you, I hope it's no bother and you find it somewhat interesting.
I'll post the specs of the Orion and draw something up I might have to use pencil and paper if Autocad is misbehaving.
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