G'day Freddy
The 4012HO might be good, try running a model.
Each time you double X-max your maximum output at low frequencies increases by 6dB. How much output do you want and how low do you want to go? Choose the size/extension/efficiency balance that suits you. Hornresponse will help you get close.
Cheers
William Cowan
The 4012HO might be good, try running a model.
Each time you double X-max your maximum output at low frequencies increases by 6dB. How much output do you want and how low do you want to go? Choose the size/extension/efficiency balance that suits you. Hornresponse will help you get close.
Cheers
William Cowan
Hi William,cowanaudio said:
I'm thinking of building the LAB12 design earlier in the thread as I still have 4 NIB drivers. I was also concerned with resoance from driver pressure as though not wide, they are long. I was thinking of a B&W style Matrix along the length of the line to break it into 4, 6 or 8 sections. Lots of rounded coutouts, and adjusted for the volume of the braces. I can't see a way to brace across the path inside the lines as that would inhibit airflow. Otherwise another layer on the outside , perhaps decoupled by grren glue or similar to tame the panel resonance.
Comments? Suggestions?
I'd electronicslly HP at 20 and LP at 50-60. Tons of power available with a rack of Quest amps, and later, a very large open plan room to fill. A pair should be fine in the current situation. Maybe 8 later, so getting the design right on a pair makes the other 6 an easy production run. They're easy to fit into and diguise in the decor in the larger room.
Brett,
I have been using a stereo pair of tapped horns with the LAB12 drivers since last spring,they work well enough that I haven't seen the need to fool with them further,at least for now.Don't have the time,anyway,with work and other projects getting in the way.
Since you already have the LAB 12s,go ahead and build one to see how it works.It would be a simple matter to replace the driver at a later date if you don't like it.
I have never tried the swiss cheese type of bracing,seems like it might cause a lot of air turbulence. My cabinets vibrate to some degree,but standing right next to them(they are in the garage)you don't hear anything.Doubling up the outside walls wouldn't be a bad idea,but will be heavy!
The tapped horns replaced my LABhorns,the LABs don't have a chance against the tapped horns below 30 hz.
Keep us posted,I would be very interested to see what you think of them.
Eight of them?Yikes!You will be the new Bass King!
I have been using a stereo pair of tapped horns with the LAB12 drivers since last spring,they work well enough that I haven't seen the need to fool with them further,at least for now.Don't have the time,anyway,with work and other projects getting in the way.
Since you already have the LAB 12s,go ahead and build one to see how it works.It would be a simple matter to replace the driver at a later date if you don't like it.
I have never tried the swiss cheese type of bracing,seems like it might cause a lot of air turbulence. My cabinets vibrate to some degree,but standing right next to them(they are in the garage)you don't hear anything.Doubling up the outside walls wouldn't be a bad idea,but will be heavy!
The tapped horns replaced my LABhorns,the LABs don't have a chance against the tapped horns below 30 hz.
Keep us posted,I would be very interested to see what you think of them.
Eight of them?Yikes!You will be the new Bass King!
Cheers William,cowanaudio said:
not optimal but Freddy did a sim earlier in this thread (~post 400) and it looked OK. If I didn't have the drivers already, I'd just go with your suggestions and the design details on your site. Can't get Peerles stuff at trade like many ithers.
How do you find these compared to ypur 18Sound OB sub?
Hi Don,Don Bunce said:
Your posts earlier in the thread gave me the idea for doing this. About 3 years ago I had a pair of corner loaded LABs in my living room, which I sold when I moved for work. I'm currently in a much smaller room so a pair will suffice. I was hoping to build a pair for use now, and work on them until I move back to my home, which is a huge open plan area.
With 8, I was thinking 4 in two pairs on the front wall (mod one each side to reverse driver), two 90* to the side and the last two at the rear. I can get them almost perfectly spaced from the couch position, and veneered / painted white (wall colour) and built into bookcases, I thought I'd have a stonking loud distributed bass (a la Toole) that's easy to build. It should also fit into the decor fairly well.
For bracing, I was thinking of something that would look similar to yours in terms of open area, just cut from a single piece as it'd be easier to do on the saw table. Add another similar to it at 90*. In 10mm play and the holes cut with a rounded router bit, turbulence should be fine.
G'day Brett
That horn of Freddy's only has 3dB more sensitivity than the driver on it's own. You should be able to get 6-10dB increase in sensitivity. There are many drivers available that have 10+mm X-max and an Fs in the 30-50Hz range. Look at some of the car audio stuff. I like the Peerless XLS and XXLS drivers because I've used many of them before and they have a great motor in them, but there are others that are worth a look too.
Cheers
William Cowan
That horn of Freddy's only has 3dB more sensitivity than the driver on it's own. You should be able to get 6-10dB increase in sensitivity. There are many drivers available that have 10+mm X-max and an Fs in the 30-50Hz range. Look at some of the car audio stuff. I like the Peerless XLS and XXLS drivers because I've used many of them before and they have a great motor in them, but there are others that are worth a look too.
Cheers
William Cowan
Hola William,cowanaudio said:
I have been looking at other drivers, but they cost money, and ATM I have none. The LAB's will do short term as I have no lack of power and have several sheets of ply here leftover from another project.
Finally got the knack of Hornresp today with TH so have been doing some modelling and have my next bass guitar LF section via a TH sorted.
Cheers
cowanaudio said:
Hi William,
actually I found it not to be easy to obtain what you proposed. My aim is to use an existing driver.
So I had to mess around a lot with the size of mouth, throat and length of the TH to find a rising response configuration.
To make life a little easier, I prepared a spreadsheet to assist. It helps to calculate the parameters for hornresp as well as it calculates additional information of the TH to be designed. May be it could be of use for you here:
Tapped_Horns_v1.xls
Finally I found the following configuration of the TH:
What scares me is that I was able to find a rising response only with a throat larger than the mouth! It looks almost like a TL. In addition this introduces a large dip @ 100Hz (compared to my last design, which has double the net volume).
Actually I do not have a clue whether this my work in practice. May the dip @ 100Hz be as bad as Hornresp promises it?
Hi Erik,Volvotreter said:
Thanks for the .xls. I'll have a play with it later.
KHorns don't go anywhere near as low as either of your designs: I know I still have a pair stacked in the hall. When I added my LABhorns below them from 70-80Hz it made a huge difference to the LF of the system. Your conicals dive just below 100Hz from memory, so perhaps the second one is better. Room gain will add to the bottom. IIRC the drivers for these were quite cheap, so byuild 4.
G'day Eric
That's a pretty funky design! I don't know what your driver's sensitivity is so I don't know If you are actually getting any gain over the driver in a vented box, but I suspect not.
You need to try a few more drivers. For a start try Fs a bit higher than your cutoff (~1.2-1.6 times seems to work well) and a Qts around the 0.4 to 0.6 mark are a good place to start. A throat of Sd/2 and mouth of 2Sd should come close to working with the right driver. If you're serious about output, try starting with something like the MTX Thunder 9500, you should be able to get great 20Hz output with that one.
When you say you want to out gun the Klipschorn, are you talking about sensitivity, max output, LF extension or all of the above? I'd assume the Klipschorn has sensitivity over 100dB/W/M and a ~30Hz cutoff, in room. You'll be able to better the cutoff fairly easily and in a small enclosure but the efficiency and maximum output will require a larger enclosure. If size and cost is not a consideration, you would be better building a large front loaded horn that couples it's flair into the room. A 20Hz horn that uses the room as a part of it's flair isn't ridiculously large and will intrude into the room only by 500-600mm. This will outgun your current horn sub by a large margin in all respects.
Cheers
William Cowan
That's a pretty funky design! I don't know what your driver's sensitivity is so I don't know If you are actually getting any gain over the driver in a vented box, but I suspect not.
You need to try a few more drivers. For a start try Fs a bit higher than your cutoff (~1.2-1.6 times seems to work well) and a Qts around the 0.4 to 0.6 mark are a good place to start. A throat of Sd/2 and mouth of 2Sd should come close to working with the right driver. If you're serious about output, try starting with something like the MTX Thunder 9500, you should be able to get great 20Hz output with that one.
When you say you want to out gun the Klipschorn, are you talking about sensitivity, max output, LF extension or all of the above? I'd assume the Klipschorn has sensitivity over 100dB/W/M and a ~30Hz cutoff, in room. You'll be able to better the cutoff fairly easily and in a small enclosure but the efficiency and maximum output will require a larger enclosure. If size and cost is not a consideration, you would be better building a large front loaded horn that couples it's flair into the room. A 20Hz horn that uses the room as a part of it's flair isn't ridiculously large and will intrude into the room only by 500-600mm. This will outgun your current horn sub by a large margin in all respects.
Cheers
William Cowan
G'day again Eric
Try the MTX Thunder T9515-04 in a 5.2M TH going from 400 to 2800cm^2 as a start. It shows flat response to 20Hz and 105dB sens when sitting in the corner of your room, all in ~700Liters. Max output looks to be around 135dB @ 20Hz. That should be almost enough in a domestic environment!
This is a 2 minute play, I'm sure you can get closer to the mark with a bit more time.
Cheers
William Cowan
Try the MTX Thunder T9515-04 in a 5.2M TH going from 400 to 2800cm^2 as a start. It shows flat response to 20Hz and 105dB sens when sitting in the corner of your room, all in ~700Liters. Max output looks to be around 135dB @ 20Hz. That should be almost enough in a domestic environment!
This is a 2 minute play, I'm sure you can get closer to the mark with a bit more time.
Cheers
William Cowan
@Brett & William
thanks for your response.
Hi Brett,
right, thats why I asked if the predictions from hornresp in regards to the dip @100Hz will come true.
Regarding the graphs itself, souldn't the larger horn be capable of a higher xover frequency?
Look for the direct comparison right here (grey is the larger, black the smaller TH):
The Eminence EPS 15-500 is not very suitable driver for a ported subwoofer application. It rolls off rapidly at 40Hz. Both TH's improve the low end a lot.
What do you think of the negative conical flare?
The initial aim was to use the existing eminence driver.
All of them if possible
What I meant was that I would like to make use of the Eminence driver and that I'm looking for the "best" choice of TH possible for this driver.
Erik
thanks for your response.
Brett said:
Hi Brett,
right, thats why I asked if the predictions from hornresp in regards to the dip @100Hz will come true.
Regarding the graphs itself, souldn't the larger horn be capable of a higher xover frequency?
Look for the direct comparison right here (grey is the larger, black the smaller TH):
cowanaudio said:
The Eminence EPS 15-500 is not very suitable driver for a ported subwoofer application. It rolls off rapidly at 40Hz. Both TH's improve the low end a lot.
What do you think of the negative conical flare?
The initial aim was to use the existing eminence driver.
All of them if possible
What I meant was that I would like to make use of the Eminence driver and that I'm looking for the "best" choice of TH possible for this driver.
Erik
Couple questions while I try to get the new Hornresp set up so I can figure out how to model these guys. I apologise if some of these have been covered, but at ~30 pages there is a lot to wade through. Pointers rather than answers welcome.
a) Has anyone modeled up something with the Pyle Pro PPA 12? Probably not the greatest driver on the planet, but it's currently on sale at PE for $28. With Fs=36, Qts = .66 it looks like a candidate for a ~30Hz horn
b) Is the TB W8-740C a non-starter? I see it's been mentioned a couple times, but I don't remember an actual sim for it. Fs does look a bit low for a 30Hz unit, unfortunately.
c) Has anyone experimented with alternate folding strategies? I am considering an experiment that would require the mouth to be ~3.5 feet down the cabinet (well, technically 3.5 feet off the floor). It doesnt' at first glance look too easy to come up with a 'two bend' setup that works well, but I haven't really spent too much time trying.
I guess a straight L shaped cabinet is straightforward enough, but it doesn't really fit well with my physical arrangement too well.
Does the driver have to fire straight out the mouth? For some reason, I'm thinking it may be easier to come up with a folding strategy if I can orient the driver 'sideways' - something that starts to look more like a Tuba. At the wavelengths involved, I can't see this being a problem, but I don't fully 'grok' the issues at play.
d) Any unexpected issues with multiple drivers? I have a bunch of 7" drivers with Fs=45Hz and Qts = .5, and given Williams ~1.5x Fs guideline, it looks like 4 per cabinet might be workable in a ~30Hz setup, albeit with limited output.
Thanks for any help - I suspect some of these questions will be obvious once I start modelling, but I guess I'm falling prey to a bit of impatience.
a) Has anyone modeled up something with the Pyle Pro PPA 12? Probably not the greatest driver on the planet, but it's currently on sale at PE for $28. With Fs=36, Qts = .66 it looks like a candidate for a ~30Hz horn
b) Is the TB W8-740C a non-starter? I see it's been mentioned a couple times, but I don't remember an actual sim for it. Fs does look a bit low for a 30Hz unit, unfortunately.
c) Has anyone experimented with alternate folding strategies? I am considering an experiment that would require the mouth to be ~3.5 feet down the cabinet (well, technically 3.5 feet off the floor). It doesnt' at first glance look too easy to come up with a 'two bend' setup that works well, but I haven't really spent too much time trying.
I guess a straight L shaped cabinet is straightforward enough, but it doesn't really fit well with my physical arrangement too well.
Does the driver have to fire straight out the mouth? For some reason, I'm thinking it may be easier to come up with a folding strategy if I can orient the driver 'sideways' - something that starts to look more like a Tuba. At the wavelengths involved, I can't see this being a problem, but I don't fully 'grok' the issues at play.
d) Any unexpected issues with multiple drivers? I have a bunch of 7" drivers with Fs=45Hz and Qts = .5, and given Williams ~1.5x Fs guideline, it looks like 4 per cabinet might be workable in a ~30Hz setup, albeit with limited output.
Thanks for any help - I suspect some of these questions will be obvious once I start modelling, but I guess I'm falling prey to a bit of impatience.
G'day again Erik
The Tapped Horn designs are very sensitive to the driver used. The wrong driver will severely restrict bandwidth and not allow you to achieve a response that is even close to flat in band. It's best to find a suitable driver and work with that. The problem with the tapped horn is you don't have the back chamber volume to play with, like you do in a FLH. It's similar to having a driver with Qts of 0.9 and trying to force it to work in a vented box, it just won't happen. Don't do the reverse taper, you won't beat a Klipschorn with that! To better the 104dB sensitivity figure you will need to get everything right.
zobsky, A corner load is absolutely not necessary. It just qualifies my sensitivity specification. The tapped horns appear to perform much better away from a corner than a compromised bass horn.
dwk123, you can try non optimum drivers and you may even get some good results. My first horns used the Peerless 830500, which isn't too suitable, but I made some good TH bass with them. The 830564's I'm using now offer greater bandwidth, flatter response and more sensitivity. The only real difference between the drivers is stiffer suspension on the 830564. Multiple drivers do work well. I've made two dual driver Tapped Horns and they behaved as expected.
Cheers
William Cowan
The Tapped Horn designs are very sensitive to the driver used. The wrong driver will severely restrict bandwidth and not allow you to achieve a response that is even close to flat in band. It's best to find a suitable driver and work with that. The problem with the tapped horn is you don't have the back chamber volume to play with, like you do in a FLH. It's similar to having a driver with Qts of 0.9 and trying to force it to work in a vented box, it just won't happen. Don't do the reverse taper, you won't beat a Klipschorn with that! To better the 104dB sensitivity figure you will need to get everything right.
zobsky, A corner load is absolutely not necessary. It just qualifies my sensitivity specification. The tapped horns appear to perform much better away from a corner than a compromised bass horn.
dwk123, you can try non optimum drivers and you may even get some good results. My first horns used the Peerless 830500, which isn't too suitable, but I made some good TH bass with them. The 830564's I'm using now offer greater bandwidth, flatter response and more sensitivity. The only real difference between the drivers is stiffer suspension on the 830564. Multiple drivers do work well. I've made two dual driver Tapped Horns and they behaved as expected.
Cheers
William Cowan
I just had another look at that MTX Thunder T9515-04 driver. It shows a lot of promise in a 20Hz Tapped Horn.
Have a look at 400-2200cm^2, total length 5.2M with the front tap 500mm back from the mouth.
570 liters internal and with one mounted in each front corner of the room, it is capable of almost enough sub bass for anyone. (143dB@20Hz)
Cheers
William (Bass Head) Cowan
Have a look at 400-2200cm^2, total length 5.2M with the front tap 500mm back from the mouth.
570 liters internal and with one mounted in each front corner of the room, it is capable of almost enough sub bass for anyone. (143dB@20Hz)
Cheers
William (Bass Head) Cowan
Wow. Just googled the driver and they're a heck of a piece of work.cowanaudio said:I just had another look at that MTX Thunder T9515-04 driver. It shows a lot of promise in a 20Hz Tapped Horn.
Have a look at 400-2200cm^2, total length 5.2M with the front tap 500mm back from the mouth.
570 liters internal and with one mounted in each front corner of the room, it is capable of almost enough sub bass for anyone. (143dB@20Hz)
Cheers
William (Bass Head) Cowan
That TH you suggested makes my LABhorns seem small. They might be good in loftspace where the bulk doesn't matter.
What about the 18LW1400's you used OB? They might make a nice TH driver.