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-   -   Horn vs. Ported (http://www.avsforum.com/forum/155-diy-speakers-subs/1615210-horn-vs-ported.html)

LTD02 07-23-2014 07:44 PM

Horn vs. Ported
 
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Cheers,


John




.

diy speaker guy 07-23-2014 09:02 PM

This is a good study but one thing is noteworthy. The front loaded horn's low knee is about a half octave below the other two designs. This is a bit unfair to the flh.

It's tricky to do a fair comparison with front loaded horns vs ported or tapped horns because a front loaded horn's low knee is below the frequency at which the tuning excursion minimum occurs while in the other two designs the low knee is above the tuning excursion minimum frequency. This also implies another problematic issue as well, namely that any high pass filters that are used will considerably lower the output of the front loaded horn down near the low knee but won't affect the other two alignments much. The extent of the effect of this hpf issue for all three alignments depends on the particular designs being studied but in general the preceding comment is a factor that definitely deserves attention.

Therefore it is my belief that the only fair way to compare these three different alignments is to use designs that have the same low knee (not the same tuning) and compare them at max spl with any applicable high pass filters in place. Overall these two considerations might not change things a lot (raising the low knee on the flh would give more output but adding a hpf would take some away), but I think that's a more fair way to compare and I think it would show the flh in a more flattering light.

Also, to keep things really fair all three designs should be simulated with the same program. Again, this might not make a whole lot of difference but there will be some difference.

notnyt 07-23-2014 09:18 PM

And this is part of the reason why I used the space I could for ported enclosures and not horns. This is further exaggerated with lower tuning.

maxmercy 07-23-2014 09:32 PM

Great analysis. The horns still rule if power is limited, though, and space and bldg materials are easily obtained. If you have the space and the time, and not so much $$, horns are a pretty good deal for low cost, low distortion SPL if you don't tune too low. Once you tune below 20Hz, the excursion demands become quite real and can only be partially offset by using multiples to raise the low corner SPL.

JSS

mhutchins 07-23-2014 09:33 PM

John,

Thanks so much for this informative simulation and comparison!

As you know, I've been wanting to build a low tuned horn for some time now, but I've never found a design that would go as low as I wanted. Now I know why! It would be monstrous, and the laws of diminishing returns certainly apply in this case! For the gain of just a few dB, you pay a huge space penalty. I guess I'll stick to my Marty sub (hopefully SUBS, by the end of summer).

Really nice comparison. Thanks again!

Mike

LTD02 07-24-2014 01:47 AM

"Therefore it is my belief that the only fair way to compare these three different alignments is to use designs that have the same low knee (not the same tuning) and compare them at max spl with any applicable high pass filters in place."

this is what I used to think as well and is what makes comparing these three systems so tricky. however, where the rubber hits the road -- max spl -- all three have the same 20hz point where excursion hits a minimum (in this comparison) and a steep rolloff under that, so the comparison is fair. it is true that under 20hz, the front loaded horn is more sensitive, so it will get to its max spl point with less power, but so what? under 20hz all three are excursion limited though, so sensitivity isn't terribly important.

the front loaded horn may have a bit of additional spl relative to the other two under 20hz, but since excursion is highly uncontrolled in all three cases under 20hz and as a result all three should have some sort of protective filter in place filtering out sub20hz content, I wouldn't want to gamble on trying to capture any of the slightly higher sub 20hz spl provided by the front loaded horn.

thank you for reading and commenting, dsg.

LTD02 07-24-2014 01:57 AM

"Also, to keep things really fair all three designs should be simulated with the same program. Again, this might not make a whole lot of difference but there will be some difference."

good point. in this particular analysis, it turns out that the areas of interest (the excursion limited zones immediately above and below 20hz for the ported enclosure) model similarly in winisd and hornresp. I just double-checked.

LTD02 07-24-2014 02:03 AM

"Great analysis."


thank you. that means a lot to me, coming from you.




"The horns still rule if power is limited, though..."


no doubt and there may actually be other benefits that aren't captured with these models, as good as they are.

LTD02 07-24-2014 02:47 AM

"As you know, I've been wanting to build a low tuned horn for some time now, but I've never found a design that would go as low as I wanted. Now I know why! It would be monstrous, and the laws of diminishing returns certainly apply in this case! For the gain of just a few dB, you pay a huge space penalty. I guess I'll stick to my Marty sub (hopefully SUBS, by the end of summer)."


i suspect that is the right call. if you have some idea/desire for a different form factor, I'd be happy to work with you on your next one--maybe some sort of push-pull, slot-loaded, mega-marty? ;-)

Decadent_Spectre 07-24-2014 03:41 AM

People around here chase the last 3-6db with great fervor and in that view 4db is significant, the sensitivity advantage is also probably lost on many who simply look at max SPL charts and disregard sensitivity and its subjective impact. Also to really chase a low tuned FLH people would need larger enclosures and multiple high xmax drivers in each from my understanding, the LAB is probably not a good choice for this since excursion is the limiting factor in the lower range. In my view a FLH is the only no compromise solution at any part of the spectrum given enough size and that is precisely why it isn't popular because no one really has the space for an optimally sized horn. I am facing this problem, I want a low tuned FLH but I don't have space for it but I also don't want to compromise and go ported/sealed. This is also why the TH has grown popular as it provides more gain around tuning in the lower region for a given size.

Just my view, appreciate the comparison John!

Bill Fitzmaurice 07-24-2014 05:54 AM

This argument is not unlike that comparing sealed to vented subs. Yes, sealed do have the advantage below the tuning frequency of vented, in a smaller package, but they don't have the advantage above the tuning frequency. By the same token, direct radiators can have an advantage below the knee frequency of a horn, but not above it. This chart shows the maximum SPL, displacement limited, of a pair of Lab 12 in a 300L 20Hz VB, and in a 600L 28Hz horn. The advantage goes to the VB below 24Hz, but above that it's not even close. Even a pair of the VBs driven with twice the power wouldn't match the output of the horn above 26Hz.
http://www.billfitzmaurice.info/imag...hornloaded.jpg

If one is going to make a simplistic assessment of the value of different alignments it would be that sealed/IB goes the lowest, at the highest cost per dB; horns have the lowest cost per dB at the expense of size, and vented box characteristics lie in between the other two. None is inherently superior across the board, neither is any inherently inferior across the board. The one to use is the one that fits your response and output needs, available space and bank account.

FOH 07-24-2014 06:07 AM

 This subject has been if particular interest to me as of late. I've spent a lot of time reading some great material. So thanks for this LTD02.


QUOTE=LTD02;25998458] there may actually be other benefits that aren't captured with these models[/QUOTE]


^ This, ... the "je ne sais quoi" with regard to the flh' characteristics.

noah katz 07-24-2014 08:07 AM

Quote:

Originally Posted by diy speaker guy (Post 25996066)
This is a good study but one thing is noteworthy. The front loaded horn's low knee is about a half octave below the other two designs. This is a bit unfair to the flh.

I thing this is a very important point, since lowering the freq x amount costs x cubed in volume, so that half octave really skews the results.

I think it's also interesting that when it comes to speakers we (myself included) are a lot more tolerant of power differences than with amps.

4 dB for the former is not *that* big of a deal, but if it was an amp we say "that's 2.5X the power!"

Ricci 07-24-2014 08:24 AM

John you are still using winisd? It’s really only good for having a database of driver parameters saved. You know HR can easily do vented enclosures and directly compare them to the horn you are modeling with a quickness… You have to use the same program for all enclosures at least!:p

Ports compress at the highest output levels so you never really get quite as much out of vented enclosures near tuning as the simulations say. Even my 10” flared power ports compress some and those will shift a TON of air. Horns can compress some too once the flow and pressures get high enough but in general the cross section is almost always much larger than typical vents and is also expanding continuously so it is less of a problem usually. Sealed or IB has no vents, or horn throat or compression chamber at all so they are free from this type of compression. You can also get noises from all of the air flow at high output levels. Once again in this aspect it is sealed/IB>horn>vented generally.

Another thing to consider is with sealed/IB/vented and other direct radiator systems the sensitivity is lower as is the maximum output and it is often easy to hear suspension and mechanical noises start to creep in once the driver gets near xmax or a bit past. Especially at the lowest frequencies where the ear is less sensitive and excursion and distortions are higher. With FLH’s and some kinds of BP enclosures the driver is buried inside of the box and any suspension or mechanical noises from the driver are filtered quite effectively so that these sounds cannot reach the ear. (Note I’m not talking about harmonic distortions here but those can be reduced a bit as well.)Not to mention that these boxes often offer a solid gain in sensitivity and max output as well which also helps offset these driver noises. What I’m saying here is that while you may be able to produce roughly the same SPL with a double driver vented enclosure versus a single in a FLH, if the drivers are being driven near their limits the FLH may still sound cleaner with the mechanical distortions and noises from the drivers operation buried inside of its enclosure.Tapped horns I would put somewhere in between direct radiators and FLH’s (or bandpasses).

Also the reduced power demands of more sensitive and efficient systems can have impacts on long term heating and distortions of the drivers. Increased current through the voice coils can have all kinds of effects on the output of the system and most of them are negative.

When you add all of that up the: Sensitivity, efficiency, lack of vents compression or noises and reduced excursion demands from a FLH, combined with the natural filtering effect on some of the garbage noises from a driver under heavy operation produce a system that sounds quite a bit different than direct radiator based systems even if you double or triple up on the direct radiators to match the output capabilities.

I really like the way a good FLH sounds and I’ve heard more than a few…There is just something about them that is different and really worthwhile. But whenever I get to designing a new system I never seem to go with them. Ever. The size is always an issue. They are either too big or they won’t go low enough or they don’t have enough output in the amount of space I have available. I tried to force myself to design one for the PH and ended up getting frustrated and scrapping the design because I couldn’t at least match a TH or vented subs with the amount of cab I had available and extension needed. I still want to design one I feel good about sharing.

Something I would like to hear one day is an uber FLH bass system covering 30-120Hz paired up with a couple TRW-17’s for the 1-30Hz.

diy speaker guy 07-24-2014 08:25 AM

Here's a couple of pictures with a bunch of screen caps that show a few interesting things. They also show how I prefer to compare different alignments. I'm not implying you did it wrong, simply that I do it differently. I prefer to compare max spl with the same low knee. Usually I do it with the same low knee with high pass filters in place but in the instance I did the same low knee without the hpf in place to make a point with row 3 and 5 in picture 1. There are a few points I want to get across and I wanted to do it without 200 screen caps. None of these designs are ideal but I didn't want to spend more than 15 minutes on this.

PICTURE 1
Row 1
- Hornresp inputs for a ported box and a front loaded horn, both with same driver
Row 2 - Schematic showing these designs are the same size (the ported box needed a massive vent to keep velocity down and it's still at 18 m/s at xmax which is a bit high)
Row 3 - Acoustical power of each design at xmax
Row 4 - Diaphragm excursion, just shown to show I am playing fair
Row 5 - Acoustical power of both designs overlaid to show that when the designs are the same size there isn't much difference in output at the low knee - this is true of most resonant vented designs including tapped horns
Row 6 - Acoustical power with hpf in place
Row 7 - Diaphragm excursion with hpf in place

http://i62.tinypic.com/21l2zgx.png

This shows pretty clearly that there isn't much difference in output at the low knee when the ported box and front loaded horn are the same size and have the SAME low knee. Once the hpf is in place the ported box wins by a bit. This also shows that low tuned ported boxes often have problems with port size and resonances inside the passband due to velocity issues.

Horns need to get exponentially larger as tuning decreases if you want flat response and ideal loading. A 30 cubic foot box with a 16 hz low knee as shown in the first post is extremely undersized, but as shown, even with this extreme limit some amount of gain is possible. Approximately the same amount of gain as a tapped horn of the same size with the same low knee.

Now let's look at the other extreme, the same ported box compared to a much larger front loaded horn. The horn still isn't large enough to be ideal size for the tuning but Hornresp has a mouth size limit so I did what I could. At over 14000 liters this isn't a practical living room design but it does show that massive gain and flat response are possible with massive enclosure size. While this design isn't practical it does become more practical if something like this is broken down into multiple units with multiple drivers and used in a large space. Multiples do work and if enough are used they will add up to an ideal full size horn, assuming the original design was an ideal full size horn with multiple drivers.

http://i61.tinypic.com/33ausef.png

Decadent_Spectre 07-24-2014 09:39 AM

Quote:

Originally Posted by Ricci (Post 26004514)
John you are still using winisd? It’s really only good for having a database of driver parameters saved. You know HR can easily do vented enclosures and directly compare them to the horn you are modeling with a quickness… You have to use the same program for all enclosures at least!:p

Ports compress at the highest output levels so you never really get quite as much out of vented enclosures near tuning as the simulations say. Even my 10” flared power ports compress some and those will shift a TON of air. Horns can compress some too once the flow and pressures get high enough but in general the cross section is almost always much larger than typical vents and is also expanding continuously so it is less of a problem usually. Sealed or IB has no vents, or horn throat or compression chamber at all so they are free from this type of compression. You can also get noises from all of the air flow at high output levels. Once again in this aspect it is sealed/IB>horn>vented generally.

Another thing to consider is with sealed/IB/vented and other direct radiator systems the sensitivity is lower as is the maximum output and it is often easy to hear suspension and mechanical noises start to creep in once the driver gets near xmax or a bit past. Especially at the lowest frequencies where the ear is less sensitive and excursion and distortions are higher. With FLH’s and some kinds of BP enclosures the driver is buried inside of the box and any suspension or mechanical noises from the driver are filtered quite effectively so that these sounds cannot reach the ear. (Note I’m not talking about harmonic distortions here but those can be reduced a bit as well.)Not to mention that these boxes often offer a solid gain in sensitivity and max output as well which also helps offset these driver noises. What I’m saying here is that while you may be able to produce roughly the same SPL with a double driver vented enclosure versus a single in a FLH, if the drivers are being driven near their limits the FLH may still sound cleaner with the mechanical distortions and noises from the drivers operation buried inside of its enclosure.Tapped horns I would put somewhere in between direct radiators and FLH’s (or bandpasses).

Also the reduced power demands of more sensitive and efficient systems can have impacts on long term heating and distortions of the drivers. Increased current through the voice coils can have all kinds of effects on the output of the system and most of them are negative.

When you add all of that up the: Sensitivity, efficiency, lack of vents compression or noises and reduced excursion demands from a FLH, combined with the natural filtering effect on some of the garbage noises from a driver under heavy operation produce a system that sounds quite a bit different than direct radiator based systems even if you double or triple up on the direct radiators to match the output capabilities.

I really like the way a good FLH sounds and I’ve heard more than a few…There is just something about them that is different and really worthwhile. But whenever I get to designing a new system I never seem to go with them. Ever. The size is always an issue. They are either too big or they won’t go low enough or they don’t have enough output in the amount of space I have available. I tried to force myself to design one for the PH and ended up getting frustrated and scrapping the design because I couldn’t at least match a TH or vented subs with the amount of cab I had available and extension needed. I still want to design one I feel good about sharing.

Something I would like to hear one day is an uber FLH bass system covering 30-120Hz paired up with a couple TRW-17’s for the 1-30Hz.

Exellent post Ricci, spot on comments that I can fully agree with. No matter how many stacked direct rads I hear, it just doesn't do what FLHs can do, its not just the sound, its also the raw force of impact. Size is the curse of the FLH...

I think something like you described in your last line would be superb and pretty much as close to perfect as one can get without an insanely sized FLH covering below 30Hz. Perhaps the Sonic Boom Generator... as I recall it was about 130db at 3Hz outdoors.

I am looking forward to your FLH design.

noah katz 07-24-2014 10:02 AM

Quote:

Originally Posted by diy speaker guy (Post 26004586)
...Now let's look at the other extreme, the same ported box compared to a much larger front loaded horn. The horn still isn't large enough to be ideal size for the tuning but Hornresp has a mouth size limit so I did what I could. At over 14000 liters this isn't a practical living room design but it does show that massive gain and flat response are possible with massive enclosure size...

Not *in* the living room, but if you just think of it as an 8' cube it doesn't seem so bad :)

MBentz 07-24-2014 11:35 AM

Ricci, have you seen this yet?
http://www.klipsch.com/kpt-1802-HLS/details
http://images.klipsch.com/KPT_1802_H...2000_large.jpg
It's a FLH with a port into the throat (a Klipsch patent)

I think you need to measure one, or at least put a couple into your home...they're only 72" x 48" x 31". While you're at it, drop a massive xmax 18" driver into it too.

Btw, hornresp assumes that the speaker is firing into an anechoic space....how does horn loading change in a finite sized room where you have a lot more loading from nearfield boundaries? I think it's different than what happens for the direct radiator.

notnyt 07-24-2014 11:47 AM

Quote:

Originally Posted by MBentz (Post 26010242)
Ricci, have you seen this yet?
http://www.klipsch.com/kpt-1802-HLS/details

It's a FLH with a port into the throat (a Klipsch patent)

I think you need to measure one, or at least put a couple into your home...they're only 72" x 48" x 31". While you're at it, drop a massive xmax 18" driver into it too.

Btw, hornresp assumes that the speaker is firing into an anechoic space....how does horn loading change in a finite sized room where you have a lot more loading from nearfield boundaries? I think it's different than what happens for the direct radiator.

That thing is just massive. Again, space vs power/displacement.

Decadent_Spectre 07-24-2014 12:00 PM

Reminds me of the Big Bertha horn.

blackoper 07-24-2014 12:17 PM

Quote:

Originally Posted by Ricci (Post 26004514)
[FONT=Arial]John

Something I would like to hear one day is an uber FLH bass system covering 30-120Hz paired up with a couple TRW-17’s for the 1-30Hz.

Im planning on making some trw-17 clones from scratch (i am partnered with a large machine shop making rifle parts). Ill post a thread on here when i do. It should be in the next 6 months. I kind of want to offer a cheap kit to the community when it is done. Anyway Im ramping production up on other things before i have time to do protyping work on it. Ive got some F20s right now but would probably make two ghorns to go with it :-)

LTD02 07-24-2014 01:18 PM

dsg, the focus of this study was max spl in the excursion-limited region.

moving the low corner of the front loaded horn higher up in frequency will result in less spl around 20hz, so that is a different analysis. that is the same thing that bfm is showing, but isn't the objective of this particular analysis.

...

ricci, thanks for the comments.


"John you are still using winisd?"
i still prefer the way max spl is handled in winisd--constant voltage into driver 're'. hornresp assumes no voltage limit, so the max spl for a given "power" is much higher than would be realized using an amplifier with that amount of power.

...

"the LAB is probably not a good choice for this since excursion is the limiting factor in the lower range."

ds, the choice of driver doesn't matter for this type of comparison. the *relative* tradeoff in spl among the systems analyzed will be the same.

Mfusick 07-24-2014 02:16 PM

Quote:

Originally Posted by maxmercy (Post 25996594)
Great analysis. The horns still rule if power is limited, though, and space and bldg materials are easily obtained. If you have the space and the time, and not so much $$, horns are a pretty good deal for low cost, low distortion SPL if you don't tune too low. Once you tune below 20Hz, the excursion demands become quite real and can only be partially offset by using multiples to raise the low corner SPL.

JSS

How come no one designs huge horns with multiple drivers with lots of excursion ? I'd be interested in something that was like that.

Just hit the issues head on, make the cabinet stupid big if that is required, and use a driver with tons of excursion. Problem solved right ? Then the horn just kicks everyone else in the teeth right ?

Mfusick 07-24-2014 02:25 PM

Quote:

Originally Posted by Ricci (Post 26004514)
John you are still using winisd? It’s really only good for having a database of driver parameters saved. You know HR can easily do vented enclosures and directly compare them to the horn you are modeling with a quickness… You have to use the same program for all enclosures at least!:p

Ports compress at the highest output levels so you never really get quite as much out of vented enclosures near tuning as the simulations say. Even my 10” flared power ports compress some and those will shift a TON of air. Horns can compress some too once the flow and pressures get high enough but in general the cross section is almost always much larger than typical vents and is also expanding continuously so it is less of a problem usually. Sealed or IB has no vents, or horn throat or compression chamber at all so they are free from this type of compression. You can also get noises from all of the air flow at high output levels. Once again in this aspect it is sealed/IB>horn>vented generally.

Another thing to consider is with sealed/IB/vented and other direct radiator systems the sensitivity is lower as is the maximum output and it is often easy to hear suspension and mechanical noises start to creep in once the driver gets near xmax or a bit past. Especially at the lowest frequencies where the ear is less sensitive and excursion and distortions are higher. With FLH’s and some kinds of BP enclosures the driver is buried inside of the box and any suspension or mechanical noises from the driver are filtered quite effectively so that these sounds cannot reach the ear. (Note I’m not talking about harmonic distortions here but those can be reduced a bit as well.)Not to mention that these boxes often offer a solid gain in sensitivity and max output as well which also helps offset these driver noises. What I’m saying here is that while you may be able to produce roughly the same SPL with a double driver vented enclosure versus a single in a FLH, if the drivers are being driven near their limits the FLH may still sound cleaner with the mechanical distortions and noises from the drivers operation buried inside of its enclosure.Tapped horns I would put somewhere in between direct radiators and FLH’s (or bandpasses).

Also the reduced power demands of more sensitive and efficient systems can have impacts on long term heating and distortions of the drivers. Increased current through the voice coils can have all kinds of effects on the output of the system and most of them are negative.

When you add all of that up the: Sensitivity, efficiency, lack of vents compression or noises and reduced excursion demands from a FLH, combined with the natural filtering effect on some of the garbage noises from a driver under heavy operation produce a system that sounds quite a bit different than direct radiator based systems even if you double or triple up on the direct radiators to match the output capabilities.

I really like the way a good FLH sounds and I’ve heard more than a few…There is just something about them that is different and really worthwhile. But whenever I get to designing a new system I never seem to go with them. Ever. The size is always an issue. They are either too big or they won’t go low enough or they don’t have enough output in the amount of space I have available. I tried to force myself to design one for the PH and ended up getting frustrated and scrapping the design because I couldn’t at least match a TH or vented subs with the amount of cab I had available and extension needed. I still want to design one I feel good about sharing.

Something I would like to hear one day is an uber FLH bass system covering 30-120Hz paired up with a couple TRW-17’s for the 1-30Hz.


What if you did not have any significant volume or enclosure size issues ? What would you design ? Could you make something work using a single sheet of ply ? 4x8 ? Or two ? 8x8 ?

diy speaker guy 07-24-2014 03:13 PM

Quote:

Originally Posted by Mfusick (Post 26015530)
How come no one designs huge horns with multiple drivers with lots of excursion ? I'd be interested in something that was like that.

Just hit the issues head on, make the cabinet stupid big if that is required, and use a driver with tons of excursion. Problem solved right ? Then the horn just kicks everyone else in the teeth right ?

It's been done. Labhorn stack with at least 6 cabinets. And I do it all the time for theoretical purposes but haven't had enough interest to actually fold something like that yet.

There are practical limitations. Not many people want to build something that they can't get through a regular size doorway or something that weighs over about 300 pounds. So individual cab size is limited to about Labhorn size, 45 x 45 x 22.5.

An ideal front loaded horn for 32 hz is Labhorn size times ~8 cabinets.
An ideal front loaded horn for 22 hz is Labhorn size times ~24 cabinets.
Max total spl for either of these stacks is theoretically around 150 db when using modern pro drivers.

Not many people need or even want something like that. It gets really big and really expensive really fast.

maxmercy 07-24-2014 03:15 PM

Quote:

Originally Posted by Mfusick (Post 26015530)
How come no one designs huge horns with multiple drivers with lots of excursion ? I'd be interested in something that was like that.

Just hit the issues head on, make the cabinet stupid big if that is required, and use a driver with tons of excursion. Problem solved right ? Then the horn just kicks everyone else in the teeth right ?

Yes, stupid big is right. You would need multiple horns to get the excursion capability down low, each of them around 4'x8'x2'-2.5'. Those are not trivial measurements, especially if you need several of them. The laws of diminishing returns will catch up to you. If you don't mind the cost and space to build hundreds of cu ft of enclosures, then multiple low tuned horns can work.

JSS

LTD02 07-24-2014 04:30 PM

"How come no one designs huge horns with multiple drivers with lots of excursion ? I'd be interested in something that was like that."


maybe. maybe not.

that first "dip" above the tuning frequency is where the system is excursion limited.


a front loaded horn that increases the spl in that region +6db relative to a ported design with the same tuning must be at least 4 times larger than its ported counterpart.


since adding a second ported cab provides +6db, the overall horn system still ends up being twice as large for the same amount of excursion limited bass.


by adding another two ported cabs, the ported system will be the same overall size as the single giant front loaded horn, but it will provide +6db relative to the horn in the excursion limited region of the bass.


...
as a side note, with four drivers in the ported setup, the sensitivity gap in the upper end of the frequency range will be narrowing and the maximum spl in the upper end of the frequency range will be about the same.

Mfusick 07-24-2014 04:38 PM

I'm planning a 36 foot long theater (25' wide) above a new construction garage, my riser will probably start around 17 or 18 feet and extend the entire way back so like 18 feet long. I was thinking I could fold some horns inside the riser.

Also, with the 25' width and full 3' false screen wall I'd have plenty of space behind the screen for more. And, if that was not enough I'd be happy to devote a back corner for another (say 50 to 80 cubes sized ) I'd want at least 4 of them, but I think having 8 might kick an amazing amount of ass. The reason I was hesitant to go this route was the ULF wasn't so great with horns most of the time, although the Ghorn seems like a winner. I have no problem building it all inside the room, my door is 36" but stair going to it are 4' wide and I can get sheets of ply into the room, as well as a table saw and anything else I'd need. I plan on cutting and working in the room anyways, actually I'll have two table saws going. One in the room and one below in the garage, plus I have a rip cut and panel saw, router etc... Skill level of build, size of the space, or the amount of wood is a total non factor for me, but I am only interested in doing it if it could be over the top excessive. I would not spend the time and effort or cost on something mediocre or average. I'd rather just build ported cabs tuned at 16hz/17hz which is rather simple for me, or perhaps try my luck with the Ghorns. I'm digesting the plans for that now, it looks a bit more complicated than a simple WINISD designed big ported slot box, but not out of reach.

Anyone wants to help me design something that kicks an amazing amount of ass you can sign up :) This won't be a pussified WAF factor restriction build :D

martinq 07-25-2014 09:07 AM

Quote:

Originally Posted by Mfusick (Post 26018834)
I'm planning a 36 foot long theater (25' wide) above a new construction garage, my riser will probably start around 17 or 18 feet and extend the entire way back so like 18 feet long. I was thinking I could fold some horns inside the riser.
...
Anyone wants to help me design something that kicks an amazing amount of ass you can sign up :) This won't be a pussified WAF factor restriction build :D

Start a new thread about this project when you're ready. Sounds like a perfect/proper sound system waiting to happen! :D

Mfusick 07-25-2014 09:59 AM

I'm ready now! I did actually start a thread but it went over like a fart in church. I've since started thinking I am better off with some ported cabs, which my comfort and skill level can pull off designing and building easier, or perhaps building horns with a pre-existing and winning design like Ghorn.

But I was thinking that making something huge and monstrous and too much might be cool. I think I just have more space to work with, and less WAF restrictions than most so I am sailing in uncharted waters here. I have no trouble or problem making a 50 cubic foot enclosure and then designing it into the back of the room, with fancy vaneer stained wood finish on the exterior, or designing my room around a superior bass solution.

I guess if worse comes to worse I could build 4 ported "marty" subs and call it a day, or design a similar cab myself (taller probably a big more volume) but that seemed rather boring to me. It would however "work" and require less effort and wood.


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