I have experience with the sauce. Dip the crow three or four times.
It's masks that musty odour!
It's masks that musty odour!
I realize that but the SR-1 is the one with the updated webpage with price, pics, (limited) specs and dimensions listed.
In all likelihood the B-40 is even worse than the SR-1 in performance. That old accordion surround driver will have xmax somewhere between 4 and 8 mm, probably closer to 4.
At low frequencies the driver is just an air pump and an old accordion surround driver is really not a good air pump.
What the B-40 will excel at is resale price. The reputation is there so it's easy to get people who have no idea what they are doing to pay way more than it's worth.
To be honest, I'm shocked that you wanted this thing at all after experiencing your own homemade subwoofers. This leads me to believe that you haven't heard them at anywhere near their potential, maybe your input voltage is too low. We'll find out when you get the new DI box. Both of your current subs are going to slaughter the B-40.
Even back before we got the system operating, some discussion took place suggesting changing out the 15 inch Dayton drivers for an 18 inch driver with a higher Xmax. I believe those Daytons had an Xmax under 10 mm.
I didn't do so - mainly because of the cost. There is room in the boards for a pair of 18 inch holes.
Does anyone have suggestions for a budget priced pair of 18 inch woofers that would work in this 12 cubic foot ported box? Two of those HT18s would probably have worked. But the only 18 inch model Stereo Integrity now offers is around $550 each.
Any sage observations?
BO
I didn't do so - mainly because of the cost. There is room in the boards for a pair of 18 inch holes.
Does anyone have suggestions for a budget priced pair of 18 inch woofers that would work in this 12 cubic foot ported box? Two of those HT18s would probably have worked. But the only 18 inch model Stereo Integrity now offers is around $550 each.
Any sage observations?
BO
SI is going to come out with a new higher priced 18 in April I think (higher priced than the one you have but lower priced than the one they are currently selling). When this hits the market there will probably a flood of old SI 18s (same model you have) on the used market. In fact I think there are already some listed for sale on avs forum. And I'm pretty sure once the uproar about the new driver dies down SI will bring back the discontinued 18 that you have again.
But you can't put 2 of them in a 12 cubic foot ported box, that won't work very well. One would probably work ok in that box.
And since you have room for a B-40, you can sell that thing and build another box for another SI 18 instead.
Other than the SI 18 there is no value like it in the current market but if you keep your eyes on the sale, clearout, buyout and used market you can find all kinds of stuff.
But you can't put 2 of them in a 12 cubic foot ported box, that won't work very well. One would probably work ok in that box.
And since you have room for a B-40, you can sell that thing and build another box for another SI 18 instead.
Other than the SI 18 there is no value like it in the current market but if you keep your eyes on the sale, clearout, buyout and used market you can find all kinds of stuff.
Don't know about sage.
But here is some Parsley Rosemary and Tyme.
If I were in your shoes, I would be looking first of all if you are getting the full output of your amp.
Art gave you a simple method. Play a 600 hertz tone on the organ c at 8 foot pitch ( I know you know that ) Flue pipe not a stopped or a reed on the Artisan settings.
Measure the voltage output from the amp.
You may not be getting all that the amp can deliver. And that may be the problem. I believe that you have a remedy on it's way if that is the case.
Next point.
Two drivers in an enclosure only give you 3 to 4 db in a real world setting over a wide bandwidth.
Voltage sensitivity gain is much over hyped on the forums. The plus 6 in sensitivity that gets repeated over and over.
Actual ability to shift air is two times as much, or 3 db greater than a single driver.
That difference will be barely perceptible.
You may recall that I'd wondered earlier within this thread if our current amp was putting out anything like it's rated output to these boxes. Perhaps the preamp will increase the signal strength coming from the Artisan output. That should provide sufficient power to these boxes. And maybe a combination of more watts and DSP from the Behringer amp will help as well.
In the previous threads where I was first beginning to discuss and research this project, you raised the issue of having too few drivers dedicated to the bass lines. You also suggested that having our large HC12 boxes in front of those homemade boxes could reduce the amount of low sounds that would make it through the shades and out into our Sanctuary. Despite what you might have thought, I did not ignore those observations. They were very valid concerns. These factors may be contributing to some of what I'm currently hearing (and not hearing). I intend to put the B-40 in front of the other speakers much closer to the opening of the organ shades. MAYBE that will do a little something to mitigate it's deficiencies. Or maybe not.
Like I said, I'm going to be experimenting.
BO
I don't think I said that at all, you said that. The bass will find it's way out.
What I said was that it doesn't make sense to devote that much space to the high frequency boxes and so little space to the low frequency boxes. I suggested moving all the higher frequency boxes out of the room and devote the whole space to a bunch of low frequency subwoofers.
The low frequency boxes require a lot more driver displacement and a lot more cab volume than the higher frequency boxes to produce spl at the same levels. You have a ridiculous amount of high frequency boxes stacked in a clump taking up a huge amount of space that the low frequencies need.
Do you have some sort of volume control?
Or perhaps a little voice inside your head that tells you take it down a notch or two? Also known as a conscience or an inner sense of right and wrong.
You can come over as quite offensive at times.
I'm saying this because I know you well enough that you most probably do not wish to be perceived like this.
Any time I have made similar attacks I try to correct it. It cheapens a person when that is the way they talk to others.
You are too intelligent of a person to have to resort to similar semi abusive communication.
Use your intelligence. Make your point politely and it will have just as much weight.
This is your problem. If you inferred anything in that post as an attack that's on you, none was implied. That post contains a bunch of facts and does not talk about anyone personally or their character at all. There's no way any reasonable person could perceive that post as an attack, that's ridiculous.
On the other hand, if you would like I could compile a list of links to posts that you have made brutally attacking people and their character and integrity, and even calling them names. Your assaults on Jeff Bagby were childish, rude and shockingly uncalled for. And you've done the same with me, calling me names and dripping with condescension.
If you want to call me out it's going to come right back to you. The hypocrisy here is unbelievable, especially considering the post you quoted is completely without insult of any kind.
Remember this little gem?
http://www.diyaudio.com/forums/subw...binet-16-hz-organ-speaker-32.html#post4442451
That's what an attack looks like. Not a single fact and the whole thing is personal and insulting. And I really don't care, it doesn't bother me. What bothers me is that you try to make me out to be a bad guy when you've posted stuff this this several times.
There's way too much chatter about feelings here. Stick to the facts. if the facts offend you, that's a personal problem.
This is misleading because it's only part of the story.
The theory is not wrong so this can be accurately simulated. Assuming the center to center spacing of the drivers is 1/4 wavelength or less at the top of the passband they are fully mutually coupled up to that frequency that c-t-c distance = 1/4 wavelength and the simulator results are accurate.
First situation -
One driver in a 50 liter sealed box with 1 watt applied vs
Two drivers in a 50 liter sealed box with 1 watt total applied (0.5 watt per driver).
An externally hosted image should be here but it was not working when we last tested it.
You get about 3 db more using double drivers but use a lot less driver excursion. And you get less than 3 db at the lower frequencies because the box size didn't change, the dual drivers feel cramped.
Second situation -
One driver in a 50 liter sealed box with 1 watt applied vs
Two drivers in a 50 liter sealed box with 2 watts applied (1 watt per driver).
An externally hosted image should be here but it was not working when we last tested it.
Now we are seeing 6 db gains across some of the passband but excursion is still lower for the dual drivers because the box size is the same. And you don't get much increase at the lower frequencies because the box size didn't change.
Third situation -
One driver in a 50 liter sealed box with 1 watt applied vs
Two drivers in a 100 liter sealed box with 2 watts applied (1 watt per driver).
An externally hosted image should be here but it was not working when we last tested it.
And that's what people talk about when they say you gain 6 db by doubling up the drivers. If you also double up the cab size and the power applied you get close to 6 db more across most of the bandwidth, certainly across the usable passband of a subwoofer. Maybe not quite a full 6 db but close.
And in this last situation the excursion is the same (per driver) as the single driver in a box half the size with half the power applied. The excursion curve is so close it overlays almost perfectly.
So yeah, you do get approximately 6 db more by doubling up the drivers as long as you double up the power too. And if you also double up the box size you get that 6 db increase all the way down into the low frequencies too.
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Good info, JAG.
How big would the box need to be for two of those SI HT18s to work well down to 16 Hz.?
Or would it be better to have two smaller boxes? I can make them tall and wide. Depth is my problem. I have to have an aisle for the pipe tech to be able to walk through to get to the pipes for tuning and maintenance.
BO.
How big would the box need to be for two of those SI HT18s to work well down to 16 Hz.?
Or would it be better to have two smaller boxes? I can make them tall and wide. Depth is my problem. I have to have an aisle for the pipe tech to be able to walk through to get to the pipes for tuning and maintenance.
BO.
Are you asking about bass reflex (in your Tapped Horn thread
) or TH?The TH would be bigger.
Although one box with a 16 Hz tuning or two boxes of the same volume with a 16 Fb result in the same output, two boxes are better in terms of lower distortion, ease of bracing, and ease of transport and installation. Two boxes also are better in terms of failure mode- Fb remains constant if one driver fails, so excursion won't kill the second driver.
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Somehow I deleted my post. Anyway, twice as big as the single driver box tb46 designed for you would work. It could be smaller or larger depending on how you want it to perform. "Work well" is relative and subjective. And Weltersys is right, a tapped horn would have to be bigger than a ported box.
One large box or two small boxes is up to you. And remember you can put a subwoofer anywhere, it doesn't have to be in the same room. You could hide a sub in a stage, in a pulpit, in a broom closet (if properly vented), in the ceiling (attic) or somewhere else. If they aren't together there will be phasing issues but they don't have to be together.
Before planning the next step though, make sure your current system is operating at max potential. As the guys have been saying a voltage measurement can only help. If for some reason that's not in the cards maybe just try visually inspecting the cone excursion.
Play a low note (make sure it's at the excursion max frequency which will be a bit above tuning if you are using a high pass filter, you can look back at tb46's design notes as he probably posted that info for the max excursion frequency) as loud as you can and visually inspect the cone. If you put a small white dot on the cone it can help. Persistence of vision will turn the dot into a line. If it's not moving about 2 inches peak to peak it's not performing to full potential. If it's moving further than 2 inches peak to peak that's fine too, as long as you stay within the driver's physical limits (xlim) and it continues to sound ok past xmax.
You can conduct the same visual experiment with your other sub box too, look for peak to peak excursion level of 2x xmax.
If you can't hit xmax you are wasting potential. This also means wasted space, as you could get the same spl from a smaller driver in a smaller box (assuming you can get the smaller sub to xmax).
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