Hi Bach On,
Just trying to see if I got your description of the available corner (see: attached). If that corner is as drawn, that will not give you a lot of volume once you subtract the wood.
Still haven't had a chance to listen to the dual driver ported enclosure? Not considering losses this should give you 16Hz/108dB @ Xmax, or 113dB for the same Eg @ 32Hz (115dB/64Hz). That should give you an idea where you are at.
Regards,
Correction: The total net volume of the corner would be about 10ft^3, so not too bad.
Just trying to see if I got your description of the available corner (see: attached). If that corner is as drawn, that will not give you a lot of volume once you subtract the wood.
Still haven't had a chance to listen to the dual driver ported enclosure? Not considering losses this should give you 16Hz/108dB @ Xmax, or 113dB for the same Eg @ 32Hz (115dB/64Hz). That should give you an idea where you are at.
Regards,
Correction: The total net volume of the corner would be about 10ft^3, so not too bad.
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Hi DrDyna,
Just trying to visualize what the OP is up against in his loft/corner. Also, makes me wonder about the volume level in the nursery? 🙂
Regards,
Just trying to visualize what the OP is up against in his loft/corner. Also, makes me wonder about the volume level in the nursery? 🙂
Regards,
Yes - your drawing is pretty close, though the angled wall joining the corner his 45 inches in length. Also, the big box is located about 18 inches more towards the corner. As you've drawn it, three HC12s currently sit side-by-side pointing into the pipe chamber. Three more will hang from the rear wall (the doorway wall) so they are not sitting ontop of the speakers on the floor. This would allow the ones on the floor to be moved more towards the rear wall. This would allow more sounds from the bass speakers to exit the speaker chamber. The wire connections are on the rear of each HC12. Current placement allows me to access to the connectors for running the wiring. After that, they can be moved as space allows. There is more opening to the right of them where a fourth HC12 could go. But the big box is blocking my putting one in that location. A further consideration is that leaving that opening would allow more sounds from the bass speaker to exit the speaker chamber into the pipe chamber - and out through the shades to the Sanctuary.
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The problem is that the big box is blocking almost 3/4 of the doorway. That makes it hard for people and any equipment to get in and out. As an example, I would not be able to take out one of the HC12s (say, for servicing) without first removing the big box. Replacing that box with one in the corner eliminates that problem.
As you've pointed out, I would lose some volume for the bass box. But the current box was always a bit large for the 15" drivers. I did estimate I'd get close to 10 cubic feet of space.
Hey. I'm not happy about this. I worked hard on that big box. It wasn't pretty, but it was tight and didn't rattle. But it isn't the right shape for the available area.
I did have a brief chance to listen to some sweeps and tones on the bass cabinet before we moved it. But I didn't use any of the new electronic measurement tools.
Bach On
Did some hard thinking last night - that doesn't come easy for me.
I've previously mentioned that there are large wooden bourdon pipes blocking the path from the speaker chamber into the pipe chamber. Those pipes are going to be removed. That will not only open the area up for sounds to exit the pipe chamber, but it will allow the front row of HC12 speakers to be moved forward. So the big bass box can be turned on it's side. Currently there wasn't room for it to fit on it's side. The space is a nominal 48 inches wide, but it was not deep enough (front to back) for the 26" depth of the box. The port on the bass box will exit towards the door.
All this reorganization will allow the space to be a bit more open for sounds to move through the speaker chamber and into the pipe chamber.
Here is a diagram that might make it a bit clearer. It isn't perfect, but it is better than what we have now.
You may recall that I'm waiting for a back-ordered 18 inch driver from Stereo Integrity due in June. It can be placed in a triangular box in that corner to the right of the doorway. I'll research the best dimensions for this cabinet.
For those who have been concerned about the lack of separation between the HC12 speakers, this has concerned me too. When we bought these speakers, the seller threw in some speakers with Allen Presence Presenters. There were eight of them. They consist of one of the Peerless 4 inch mid-range speakers and the same tweeter as the HC12s. Each of these has it's own crossover system. I removed these from the Dummy Boxes they were in. I built small open backed cabinets around six of these. I've ordered L-Pads for each and six adjustable speaker hangers. These can be placed on the walls or the ceiling of the wider pipe chamber to provide a better separation of each stereo pair. I'm hopeful they will do the trick. If not, we'll buy some newer horns and a crossover for this purpose. If there isn't enough in the budget now, more money will gradually replenish the Organ Fund, so they can be bought later.
No. This isn't perfect. But I think things are some better.
Bach On
An externally hosted image should be here but it was not working when we last tested it.
I've previously mentioned that there are large wooden bourdon pipes blocking the path from the speaker chamber into the pipe chamber. Those pipes are going to be removed. That will not only open the area up for sounds to exit the pipe chamber, but it will allow the front row of HC12 speakers to be moved forward. So the big bass box can be turned on it's side. Currently there wasn't room for it to fit on it's side. The space is a nominal 48 inches wide, but it was not deep enough (front to back) for the 26" depth of the box. The port on the bass box will exit towards the door.
All this reorganization will allow the space to be a bit more open for sounds to move through the speaker chamber and into the pipe chamber.
Here is a diagram that might make it a bit clearer. It isn't perfect, but it is better than what we have now.
You may recall that I'm waiting for a back-ordered 18 inch driver from Stereo Integrity due in June. It can be placed in a triangular box in that corner to the right of the doorway. I'll research the best dimensions for this cabinet.
For those who have been concerned about the lack of separation between the HC12 speakers, this has concerned me too. When we bought these speakers, the seller threw in some speakers with Allen Presence Presenters. There were eight of them. They consist of one of the Peerless 4 inch mid-range speakers and the same tweeter as the HC12s. Each of these has it's own crossover system. I removed these from the Dummy Boxes they were in. I built small open backed cabinets around six of these. I've ordered L-Pads for each and six adjustable speaker hangers. These can be placed on the walls or the ceiling of the wider pipe chamber to provide a better separation of each stereo pair. I'm hopeful they will do the trick. If not, we'll buy some newer horns and a crossover for this purpose. If there isn't enough in the budget now, more money will gradually replenish the Organ Fund, so they can be bought later.
No. This isn't perfect. But I think things are some better.
Bach On
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Why not simply measure what you have and then you'll have some notion of where to go, instead of continuing to invent elaborate theoretical options of every sort?
I think it is fair to say that nobody has shown much confidence in anticipating the sound in your church.... even if your box advisors are confident about the specific output in the neighbourhood of your box.
So give it a try with a mic (after devotions of course).
And Happy Mother's Day to all who celebrate it.
Ben
I think it is fair to say that nobody has shown much confidence in anticipating the sound in your church.... even if your box advisors are confident about the specific output in the neighbourhood of your box.
So give it a try with a mic (after devotions of course).
And Happy Mother's Day to all who celebrate it.
Ben
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Have you considered the possibility to play some organ music through the setup and see what it sounds like?
Would take some setting up in proper pairs series and parallel and either a music player or a CD to feed the beast.
At least you would be able to set up something in a recording that you could do some useful comparative listening with.
Would take some setting up in proper pairs series and parallel and either a music player or a CD to feed the beast.
At least you would be able to set up something in a recording that you could do some useful comparative listening with.
lab 12 TH??
I'm not an expert at all... but I hear the LAB 12 tapped horn 2 or 3 weeks ago! the box are not so big! and the go really low! I love the LAB12 driver because he can produce low notes without distortion! There was only 2 box and the bass was damm good... with 8 box it will be better... I think it can go low to 16hz... you can probably find a plan online for 16hz notes!
I'm not an expert at all... but I hear the LAB 12 tapped horn 2 or 3 weeks ago! the box are not so big! and the go really low! I love the LAB12 driver because he can produce low notes without distortion! There was only 2 box and the bass was damm good... with 8 box it will be better... I think it can go low to 16hz... you can probably find a plan online for 16hz notes!
Attachments
I setup all six of the HC12s and the big box with the single 15" and no port. Used splitters and patch cords from a CD to play through all four amps. The sound was excellent for organ music. But the same signal was going to each stereo pair. Thus, the woofers on the HC12s were playing the same bass notes as the bass box. (That won't be the case when we use the sound engine. It will send pedal voices ONLY to the designated pedal speakers.)
I had several people listen to the setup - including two organist friends. All of them were impressed with the fidelity. But I didn't have the sound measuring equipment and software at the time. Then I had to move the equipment into the pipe chamber. I haven't had time to get everything reconnected. Like it or not, I have to share the building with people who have no appreciation or concern about the organ.
I will get some measurements ASAP, but I have one or two other things to do in my life - including doing some things for my wife.
Bach On
Bach On
Hey, I think that's my picture! In fact, yes, I recognize the old volume knob on my lightswitch dimmer, haha!
Pipe loft layout and subwoofers.
Hi Bach On,
Post #545: "...pipes are going to be removed...the big bass box can be turned on it's side...port on the bass box will exit towards the door..."
That sounds like a good solution. The big box should work well w/ the dual 15" ST385 or a single 18" SI HT18.
Post #545: "...waiting for a back-ordered 18 inch driver from Stereo Integrity due in June. It can be placed in a triangular box in that corner to the right of the doorway. I'll research the best dimensions for this cabinet."
I feel it would be a good idea to build a box with a similar response to the big box. The main output at the very low frequencies comes from the port(s), the easy way to keep those two boxes in phase is to build similar enclosures, i.e.: bass reflex tuned to about the same frequency. You don't have to worry too much about the size, whatever fits the corner is going to be slightly smaller than ideal 🙂. After taking a closer look at the corner I come up w/ an internal net volume of roughly V_net=8-8.5ft^3. It might be better to use a shelf port instead of the round port (?). I made a sketch of my basic idea. There is a lot left to be fleshed out, e.g.: you'll need some driver protection in front of the driver(s), the internal bracing needs to be worked out. But basically, this should work.
Post #545: "...Allen Presence Presenters...Peerless 4 inch mid-range speakers and the same tweeter as the HC12s."
Xrk971 has done a lot of work w/ small wide range drivers (search in the fullrange forum). Maybe something like the FaitalPro 3" to 5" drivers would work for you as fillers in multiples? E.g.: the 3FE25/$19.-- or the 4FE35/$24.99. Lots of ways to do this.
US SPEAKER - 6" & 8" Speakers - 6" & 8" speakers by Eminence Speaker, JBL, Vifa, EV, RCF, Beyma, Peavey, Celestion, P.Audio, Ampeg, Crate, Jensen, Fane and Pyle. 6" bass speakers & 8" bass speakers. Find the right 6" or 8" woofer here.
Regards,
Hi Bach On,
Post #545: "...pipes are going to be removed...the big bass box can be turned on it's side...port on the bass box will exit towards the door..."
That sounds like a good solution. The big box should work well w/ the dual 15" ST385 or a single 18" SI HT18.
Post #545: "...waiting for a back-ordered 18 inch driver from Stereo Integrity due in June. It can be placed in a triangular box in that corner to the right of the doorway. I'll research the best dimensions for this cabinet."
I feel it would be a good idea to build a box with a similar response to the big box. The main output at the very low frequencies comes from the port(s), the easy way to keep those two boxes in phase is to build similar enclosures, i.e.: bass reflex tuned to about the same frequency. You don't have to worry too much about the size, whatever fits the corner is going to be slightly smaller than ideal 🙂. After taking a closer look at the corner I come up w/ an internal net volume of roughly V_net=8-8.5ft^3. It might be better to use a shelf port instead of the round port (?). I made a sketch of my basic idea. There is a lot left to be fleshed out, e.g.: you'll need some driver protection in front of the driver(s), the internal bracing needs to be worked out. But basically, this should work.
Post #545: "...Allen Presence Presenters...Peerless 4 inch mid-range speakers and the same tweeter as the HC12s."
Xrk971 has done a lot of work w/ small wide range drivers (search in the fullrange forum). Maybe something like the FaitalPro 3" to 5" drivers would work for you as fillers in multiples? E.g.: the 3FE25/$19.-- or the 4FE35/$24.99. Lots of ways to do this.
US SPEAKER - 6" & 8" Speakers - 6" & 8" speakers by Eminence Speaker, JBL, Vifa, EV, RCF, Beyma, Peavey, Celestion, P.Audio, Ampeg, Crate, Jensen, Fane and Pyle. 6" bass speakers & 8" bass speakers. Find the right 6" or 8" woofer here.
Regards,
Your drawing is much better than mine. I like the look of that corner box. I believe I can do that port. But I wonder about one thing. You've drawn the speaker face of the corner box sloping back from the door end in the direction of the corner. I'd estimate it is leaning back something like a 70-75 degree angle.
I figured to turn that joint into a right angle. My calculations were that a 24 inch wall against the nursery wall and a 24 inch wall for the speaker face would require a 34 inch angled wall. That would get the raw volume to 10 cu. ft. with a 60 inch height on the cabinet. Or did I goof up in my calculations? Mine would look like a right triangle with the 90 degree at the door. My number crunch on the volume is that it's a square divided by 2, multiplied by the height.
Thanks for the suggestions. One of the organ techs is concerned that Stereo Integrity didn't post the specs for the 4 ohm version of the 18 inch driver, just the 2 ohm version. I ordered the 4 ohm - which is backordered. He's suggesting that I wait to build the cabinet. I'm just not confident that they will send the specs with the driver.
Any thoughts?
Bach On
Hi Bach On,
Post #553: "...I figured to turn that joint into a right angle. My calculations were that a 24 inch wall against the nursery wall and a 24 inch wall for the speaker face would require a 34 inch angled wall..."
Yes, that changes things. It's just so hard to communicate even simple geometry without a picture.
Taking height as H=73.5", and staying 1/8" away from the walls, I get:
- For the driver baffle across the corner (my initial try) V_net=8.55ft^3,
- for your 24"x24"x34"triangle I get V_net=~7.75ft^3, and
- taking the whole corner triangle w/ your method ~ 29.5"x29.5"x41.7" V_net=13.37ft^3, or about the same as your original big box.
You still have some time to think about it, but the biggest box has my vote. Maybe a 1.5" setback from the corner for 28"x28"x39.5"?
As to the driver specs, I don't know how reliable SI's specs are either, especially when they don't give any, but from other projects (e.g.: avsforum) I would assume they generally are in the ball park. You could measure the specs yourself. There is quite a range of tuning in your big box w/ the SI HT18: for your 7-3/8" port anything from 24"(probably best for the 18") to 34" port length should work fine, that's a big tuning range. Good your organ tech brought it up, it would probably be best to design in some relatively easy adjustability for the port.
Let me know what size you can live with, and I'll try to make a more complete drawing if you want me to.
Regards,
Post #553: "...I figured to turn that joint into a right angle. My calculations were that a 24 inch wall against the nursery wall and a 24 inch wall for the speaker face would require a 34 inch angled wall..."
Yes, that changes things. It's just so hard to communicate even simple geometry without a picture.
Taking height as H=73.5", and staying 1/8" away from the walls, I get:
- For the driver baffle across the corner (my initial try) V_net=8.55ft^3,
- for your 24"x24"x34"triangle I get V_net=~7.75ft^3, and
- taking the whole corner triangle w/ your method ~ 29.5"x29.5"x41.7" V_net=13.37ft^3, or about the same as your original big box.
You still have some time to think about it, but the biggest box has my vote. Maybe a 1.5" setback from the corner for 28"x28"x39.5"?
As to the driver specs, I don't know how reliable SI's specs are either, especially when they don't give any, but from other projects (e.g.: avsforum) I would assume they generally are in the ball park. You could measure the specs yourself. There is quite a range of tuning in your big box w/ the SI HT18: for your 7-3/8" port anything from 24"(probably best for the 18") to 34" port length should work fine, that's a big tuning range. Good your organ tech brought it up, it would probably be best to design in some relatively easy adjustability for the port.
Let me know what size you can live with, and I'll try to make a more complete drawing if you want me to.
Regards,
tb46
First, I am aware that you put time, experience and effort in the drawing you posted. I would be remiss if I didn't express my strong appreciation.
Here's my crude drawing of what I envisioned. Dimensions on it can changed. But the angle at the door is different. That creates a little more internal space.
This one would be a little deeper into the corner. On yours, the driver was turned more towards the opening - that could be better since volume is a concern. I'm just trying to get a slightly larger number of cubic feet.
Bach On
The cowboy saddled his horse and ran off in all directions.
Seems to me, the next step is test what you have. And take it from there. Or not.
Maybe the test protocols seem forbidding? The simplest test is to just get a friend with a secret hand on the switch and see if listeners can characterize the difference between presence and absence. Not the kind of detailed information REW provides, but a million times* better support for decision-making than plugging numbers into a sim or calculating volumes in the privacy of your room.
Preparation for that test procedure requires approximately zero time and no equipment.
Ben
*just an estimate. I could be off by an order of magnitude or two.
Seems to me, the next step is test what you have. And take it from there. Or not.
Maybe the test protocols seem forbidding? The simplest test is to just get a friend with a secret hand on the switch and see if listeners can characterize the difference between presence and absence. Not the kind of detailed information REW provides, but a million times* better support for decision-making than plugging numbers into a sim or calculating volumes in the privacy of your room.
Preparation for that test procedure requires approximately zero time and no equipment.
Ben
*just an estimate. I could be off by an order of magnitude or two.
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Hi Bach On,
I think I got it. I'll see if I can get to calculating the volume, etc. tomorrow.
Regards,
I think I got it. I'll see if I can get to calculating the volume, etc. tomorrow.
Regards,
I just thought I'd post to mention that I did not get any specs when my SI drivers arrived.
I'm interested to see how this turns out 🙂
If you are porting, would placing a rectangular port at the bottom, so that the floor is kind of an extension of one side of it, help extend the tuning lower slightly?
I'm interested to see how this turns out 🙂
If you are porting, would placing a rectangular port at the bottom, so that the floor is kind of an extension of one side of it, help extend the tuning lower slightly?
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