| Looking for extreme low loud bass...el pipo, horns,... - Click HERE for Original Thread |
| pat allen |
Hi, subject says it all.
I am just finishing to rebuild a freaking power amp, and fallen into my hands a nice sub for very cheap.
The sub i have is a car subwoofer, SWX 1242D capable of 1000wrms, 3000 peak, 12 inches, dual 4 ohm voice coil.
The amp is a QSC usa 900 clone, sligtly modified to pump around 1000wrms at 8 ohm in bridged mode.
I also have a "down converter" which takes the fundamental frequency down low and divide it by two and put it back into the music...it remembers me the so called "Epicenter" from Audio control, for car system applications. It realy makes the difference !!!
So, i have also a 12 inch concrete tube...it just lends me to build a EL PIPO.
(COPY/PASTE FROM THE WRONG FORUM, SORRY)
sub spec
I am also thinking about a front loaded horn, but i am totaly lost as to where to start picking up info for this. I searched a bit on this site, i returned me either super specific info with complicated calculations, or elusive info.
Can i have some help my friends ??
I have enough space, i am using my home basement for the project.
Is there any calculators tha i can download and enter my sub specs and "fo" wanted, then it returns most of the dimensions to build the horn ??
Id like to get pictures of finished projects similar to mine.
thanks !! |
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| Fish Chris |
if their are any "Transmission Line Subwoofer" calculators out there, I'd sure like to find one !
I'm fixing to start experimenting with TL setups myself. I have searched unsuccessfully, for some type of calculator. So now I think I have decided to just get me a nice big sonotube (probably a 16" or 18") x 14ft or so. Then attach a couple of 15" Dayton Titanics to one end of it {in a push-pull configuartion}, and start playing around with this and a frequency meter. Too low... cut off some pipe. Too high.... add some stuffing.
On the one hand, a calculator would be great..... But on the other hand, personally speaking, I think I might take a little more pride and satifaction in the project if I did it myself, and it then especially if it came out bombastic :-)
Peace,
Fish
PS, This guy is using two 10"s in each of these tubes. http://www.teresaudio.com/haven/subs/subs.html
This setup seems kind of modest to me.... but then this guy was not trying to rock the house down either. He was just shooting for the "nicest sounding bass" he could get, and claims he has found it with this setup. |
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| pat allen |
I know how you feel ;)
I made few test last years with my actual sonotube.
12 feet long, 12inches diameter. I was using a 12inch subwoofer that i was already having, not good quality.
I made some sound test with a frequency generator. The tube was horizontal. I read somewhere that it MUST be vertical...:confused:
Anyway, i got some noise going out of it, but was a bit disapointed about the SPL. There was something like 100w in play.
Its been 2 hours now that i am searching this forum...
there is a lot of simple questions unanswered, and there is far more bla bla bla (no offence to anyone plz) rather than real buildups or physical tests.
simple question like:
1-what kind of "system" makes the most SPL
2-what is the easiest one to build
3-what is doable and what is not
practicaly speaking, a system that makes terrific spl, but within a very narrow bandwidht is out of equation...
My quest is to build "something" that can makes music sound like music, from anything in between 0hz and 100hz, where most of the "normal on the shelf" speakers literally stop to play...
AND/OR something that makes the house going off of its foundations...
i wonder what 0hz sounds like...anyway...
I played a lot in the past in car audio, i made a lot of good "kit" with many subs, the better one was with 4 12 inches in a minivan. It was quite loud and very disturbing ;)
i played with...bandpass, double bandpass, compound, ported, sealed,...
i know how good bass feel, and id like to make it in my house :D
I have big thought about a front or rear loaded horn. The fact that it can extend the fo of the sub 1/2 is tempting, but seems a lot complicated to build and calculate. |
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| freddi |
the late Bob Bullock's free DOS t-line boxmodel program might (?) work - someone here may have a feel for specifying stuffing density so could ~correlate to MJK's work (?)
http://www.hal-pc.org/~bwhitejr/ |
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| Cameron Glendin |
Ive made a few sonotube pipes subs and all I can say is that they are worth the effort.
one was made with a 12" 8ft length of pipe and a 12" kenwood car stereo driver siliconed into place. pipe is filled with polyester
the other uses a 4" voice coiled 18" (industrial 98 db@1w, 1m) in a 10ft pipe, 18" diameter, siliconed into place. filled with fiberglass
I have used them both vertically and horizontally with no noticable difference.
The first system lives in my living room, The second lives in a 250 seat cinema.
awesome is a common comment at the cinema! |
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| AndrewT |
Hi Pat,| quote: | | I am also thinking about a front loaded horn, but i am totaly lost as to where to start picking up info for this. I searched a bit on this site, i returned me either super specific info with complicated calculations, or elusive info. |
most of the information on this site and the references quoted in it are consistent. There are anomalies but often they are more to do with the amount of truncation of the true horn and the sound (depth and quality/response variation) that results from that truncation (cutting off the horn before it reaches it's required length/mouth area).
The facts are.
1. the mouth circumference >= wavelength of the lowest frequncy to be reproduced.
2. the flare rate, controlling the length, is related to the lowest frequency to be reproduced.
3. the horn length >=either a quarter or a half wavelength of the lowest frequency to be reproduced.
4. the throat area should be related to the cone area, usually equal to or down to one third Sd area.
5. the frequency range from a horn loaded driver cannot approach the ten octaves in normal music. Usually it is divided into two or three octave segments and each is designed for appropriately.
6. the room loading on the horn can usefully reduce the mouth area required for good sound reproduction. This is usually only applied to the bass frequencies, mid and treble frequency horns are usually designed for operating into free space.
The result of all this is that as the required bass frequency goes down the bigger the horn becomes, in volume, length and width. |
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| AndrewT |
| quote: | Originally posted by Cameron Glendin
Ive made a few sonotube pipes subs and all I can say is that they are worth the effort.................the other uses a 4" voice coiled 18" (industrial 98 db@1w, 1m) in a 10ft pipe, 18" diameter, ............The second lives in a 250 seat cinema.
awesome is a common comment at the cinema! |
I have aquired a pair of 18inch drivers but with a low Xmax. would these be suitable for Sonotube loading?
How much power does one need for a Sonotube to give effective bass and sub-bass?
How far below Fs does a Sonotube go and still be effective? |
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| Fish Chris |
Hey Cameron G, each successful TL subwoofer pipe I hear of, gives me that much more confidence.
I notice you said they work fine horizontal.... as I originally suspected.... Although I think I have figured out at least one reason this is not rcommended > The stuffing needs to be spread evenly, and given some time and use, if layed on its side, the stuffing might tend to squash down to the bottom side. Maybe if one could find a stuffing with more body... like maybe furniture batting ?
Peace,
Fish |
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| Cal Weldon |
Fish,
You might want to try basalt insulation. Sold as Rock Wool among other names. Not likely to compress over time. |
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| cyclotronguy |
The idea of standing vertical invloves boundary loading..... ie Allison technique... turning 4 pi space into 2 pi space.
With a long enough tube, ya gets the woofer loading into the floor and the vent at the ceiling.
Cyclotronguy |
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| qwad |
| :D cheers you might want to check out the bib thread here i you can find it in the loudseaker section in the full range section:apathic: hope this helps think its worth you checking it out cheers TC:devilr: |
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| pat allen |
:xeye: i still dont have some clear idea as to which design to choose... horn or tl ?
what should i expect from both if properly designed ?
i will try the tl for sure asi have all the material to do it, but i would like to get some idea with my Alpine sub spec, what box dimensions it could be for the horn type.
What are the basics with horn type, such as, do i have to choose a fo, 1/4 or 1/2 lenght,...
Sure that my wich is to find someone kind enough to help me design or find box dimensions for a horn box with my sub spec.
:xeye:
thanks. |
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| AndrewT |
Hi,
tell us how low you want the bass horn to go and we'll tell you if it can fit inside the house.
Will it be floor (one boundary) or floor+wall (two boundaries) or corner (all three boundaries) loaded?
How much truncation do you think you can accept?
I have no idea, all I know is that more truncation means more deterioration in performance. |
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| Cameron Glendin |
Andrew, the speaker seems to load well with the pipe, whether it reacts like a large infinite baffle or a ported design I do not know.
I have always liked the sound of voight 1/4 wavelength styles of speakers and have used a tapered pipe (6.5inch Vifa 2 way) as my main speakers for over 10 years now. When it came to adding a sub, the natural 1/4 wavelength bass sound was my modivation to experiment. It was far easier than I suspected.
My approach was simple, tune the pipe to the 1/4 wavelength of the speakers fs, fine tune with dampening material. The most time consuming aspect of the project was picking up the pipe from Boral formworks, and each was made and working on the same day.
To me 1/4 wavelegth speakers have a more efficient low end than ported or sealed. I cannot comment on horns, but am very tempted to try to build one next! Audio Express have an interesting design recently published. A friend of mine boosts the 27hz in his horns and they sound awsome!
Other 1/4 wavelength ideals that I have had luck with is the use of Altec inspired wings/ baffles added to the sides of standard style cinema speakers. I guess that if you create the conditions to create a more perfect wave, the more natural the sound.
I usually place my 8 ft pipe in the corner with the driver facing down on 2" feet and the other end only is a few feet from the ceiling, when I place it on its side, it is then fairly close to both side walls, so perhaps the results are only similar due to the shape of my particular room.
The cinema is set up driver facing down at 1/3 width behind the screen. The sub is powered by a 300w amp and has had no problems at extreme sound levels and its a big room! it is only required below 50hz.
Most of my work done in cinemas I have seen the results through a spectrum analizer, unfortunatly not in this case with the pipe sub. To my ears/bones the result is equally as impressive as my last cinema sub which was based on an expensive EV driver ($ 750 )with a foam surround in a 600 litre box tuned to 25hz, it was measured 3db down at 25hz. The sonotube used a cheaper driver ($400 )with a cloth surround (tighter suspension).
Now I do not understand the theory, but have been told that a usable response from 22hz can be expected from the sonotube sub. Hopefully I will see the results through a spectrum analizer one day.
Next time I make one I will be using rockwool as the dampening material!:) |
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| GM |
Greets!
http://www.crutchfield.com/S-AuK3sU...=500SWX1242#Tab
According to these published specs an Alpha TL (which is basically what the El Pipe-O is) tuned to Fs would be:
L = 117.38"
CSA = 25.481"^2 (~5.696" dia. or 5.048" square)
stuffing density w/ polyfil = 0.781 lbs/ft^3 (21.63 oz total)
These can be rounded up to the nearest inch/whatever without penalty. Considering the driver's highish Qts and power rating, I'd use at least a ~6" pipe.
WRT FLH, this driver really wants to be BH loaded, which if there's enough room (probably not) and budget will get down to around 9 Hz with a ~43% calc'd efficiency (108+ dB/W/m half space), but a ~19.8 (or less) - ~70 Hz FLH is doable too. Any higher and the CR gets too high.
GM |
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| Fish Chris |
First off, please don't take this as if I'm arguing with you, as you wouldn't have to know much, to know more than me. However, I have read (and gained as much, in viewing successful TL horn designs) that a 12" sub should have at least a 12" diamter pipe.... if not 13" or 14". Remember El-Pipo used a 24" pipe, for two 21" inch subs.... then later, for single 21" subs....
How do you conclude that a 6" pipe would be okay for a 12" woofer ?
Here are the specs for the 15" sub woofer(s) I'm looking at:
http://www.partsexpress.com/pe/psho...tnumber=295-420
I was thinking of at least a 16" diameter pipe, if not 18"...... No ?
Geeez, what I'd give for a straight up TL design calculating program.... just type in the woofer specs and click go.....
Peace,
Fish |
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| GM |
Greets!
Conventional wisdom says use a pipe of ~the same CSA as driver Sd, but it's BS and even the pioneer speaker designers knew this since it was well known from building pipe organs that the circumference of a pipe sets its LF cutoff, so to get around this humongous size required they put the driver in a big box and tapered it down to a big, long tube vent that was equal to ~Sd to keep acoustic efficiency fairly high. Somewhere along the line the box was reduced because as more power became available they didn't need so much box efficiency, then dropped altogether as the Vas of the drivers dropped (acoustic suspension era) and continues unabated today in the quest to get ever smaller cabs and why this ultra low Vas driver only requires a small pipe to load it properly.
So much for 'conventional wisdom'. It was ~valid at one time, but no longer unless a high Fp is desired or acceptable.
That said, the bigger the pipe the greater its gain up to a point of diminishing returns, which is around 4x Vas, so at ~7810.6"^3 for this driver, a ~9.2" dia. is the theoretical point of diminishing returns in a ~117.38" long pipe. There's a trade-off for this extra gain though, its Qp will be higher, as will its harmonic distortion, so will require more stuffing for best performance.
WRT a 'straight up' TL calculator, many moons ago I posted an Alpha TL Excel spreadsheet based on Rick Shultz's formulas, which I believe were an extension of G.L. Augspurger's work and the one I used. For a more flexible designer that allows tapering and driver location at other than the closed end of the line, download MJK's Classic TL paper and make your own calculator.
WRT the Titanic, for Fp = Fs:
L = 168.31"
CSA = 73.963"^2 (~9.704" dia. or 8.6" square)
stuffing density w/ polyfil = 0.461 lbs/ft^3 (53.13 oz total)
Max pipe size = ~20.2" dia.
GM |
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| pat allen |
| quote: | Originally posted by AndrewT
Hi,
tell us how low you want the bass horn to go and we'll tell you if it can fit inside the house.
Will it be floor (one boundary) or floor+wall (two boundaries) or corner (all three boundaries) loaded?
How much truncation do you think you can accept?
I have no idea, all I know is that more truncation means more deterioration in performance. |
OK, my quest is to fill the gap into my home theater.
I cant realy fit anything into the listening room, but i can use the whole home basement to do it.
So my idea was to bolt the tl line right under the floor of the listening room, and could even use a 90 degree elbow and vent it behind the stereo/tv cabinet with a fake register...
so i want deep low loud bass...
the front loaded horn also seemed to me to be good because of the spl output it seems to make...
If i go this route, it will reside on the concrete floor, in one corner of the home basement.
I do believe fun happens with home cinema with 15hz thru 80 hz...
And, i dont have any idead as to what you means with "truncation, boundary,...".
thanks. |
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| AndrewT |
Hi,
for 15Hz you require a VERY big horn.
I'll give some numbers and you'll see the futility of bass and sub-bass horns.
Using two 18inch drivers and setting throat area = 2*Sd makes the horn shorter.
Using floor and wall loading i.e. putting the horn mouth up against a wall AND floor junction reduces the horn mouth by 75%. This also shortens the horn.
The horn length should be 8.3m (=27feet) and the mouth area= 20.8sqm (=224sq Feet).
If you truncate it (chop off the front end to make the horn shorter and the mouth smaller) by 50% then the horn length is 4.15m (=14feet) and the mouth area is reduced to 2.1sqm (=23sq Feet). That is still a big horn and the performance in the range 15Hz to 30Hz will be severely compromised. This truncated horn is too short, the minimum length is between 5.7m and 11m (quarter to half a wavelength).
One can either truncate less and add back in some of that big mouth or go to the small end and make the throat smaller (this requires a lot less volume).
If you use one driver (throat =1*Sd), the horn will increase in length by 1.25m and if you reduce the throat to half of Sd then it will increase in length by a further 1.25m. The 50% truncated horn is now 6.65m (=22Feet) long (comfortably over 5.7m).
Do you have sufficient space in your floor for a mouth that size?
A 15Hz horn is only for incorporation into the design of the building not as an add-on.
A 20Hz horn is a lot smaller and 27Hz is very much smaller again, have a look at Tom Danley's Labhorn. Download his paper on designing the speaker for lot's of detail. |
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| GM |
Greets!
Bottom line, low tuned TL or multiple driver IB, with the latter preferred since there's a trend to ever lower content being added to the LFE channel. I saw a measurement awhile back with a near DC cutoff in one of those animated movies, so a bunch of mass loaded drivers in a IB manifold seems the way to go and XO this sub around 35-40 Hz to a somewhat more compact dual driver bass corner horn (or two ;)) such as the LABhorn to get the high res/SQ/'slam' of the most audible portion of the LFE's BW.
GM |
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| AndrewT |
Hi Gm,
your posts always seem to impart knowledge.
When are you going to write a Wiki for us? |
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| GM |
Greets!
Thanks, I try as best I can.
On what? there's already a horn one and I defer to the 'Cult of the Infinitely Baffled' on all things IB. Regardless, I'm not going to potentially waste my time writing something instructive that just anyone can change without my knowledge/permission.
GM |
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| Fish Chris |
Finally some actual numbers I can work with.... now if I could just understand all of these numbers completely, so that I might be able to make any neccessary tweaks.
Correct me if I'm wrong, but I believe the "Alpha" set up you provided the numbers for, is a "half wave" pipe ? ...and of course the Omega is a quarter wave, which is quite workable, but not as efficient.
So back to the Alpha, as I think I can deal with a pipe (or two) of 146 1/4"......
Just a few concerns;
1) What is the actual tuning frequency of this design ? Or, more importantly, how much 20Hz to 25Hz bass will I get with this set up ? {remember, I will be using this set up, in conjunction with a HT that already includes a 12" powerd sub woofer, that should be able to handle mid base, down to 40Hz sub base just fine... I'm really only wanting to reinforce the lower end (40Hz and down)... big time ;-)
2) My sono tube will have to be 10" diameter. The chart shows calculations for a 9.7" diameter pipe. What adjustments do I need to make with the length, amount of stuffing, etc, to keep the performance equal ?
3) Is it advisable to attach a 10" pipe, right flat to the face of a 15" sub (no small enclosure in between, but rather, a flat face plate, with a 10" hole in the center of it) ? I guess this might help to prevent the sub from bottoming out so easily, huh ?
Thanks again GM,
Peace,
Fish |
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| GM |
Greets!
BTW, I forgot to add a PW to the spreadsheets, so to keep from potentially screwing up the programming I recommend adding your own so that you can only input values in red........
GM |
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| pat allen |
hum hum, excuse me guys...
should i start a new thread and let you talk in between you ?
It is very cool that you exchange all this info, but id like the thread to stay focussed on my questions :confused:
i mean, the discusion is going here and there...i just dont get it. Should i read all this talking, is it relevant to my questions ? i just dont know !!
i dont have any 18 inches sub, i only have a 12inch one and that is what i want to use, nothing else.
The only thing i understand now is that a horn can get very big if you are not specific enough with your question/spec.
thanks. |
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| jeff mai |
| quote: | Originally posted by pat allen
i mean, the discusion is going here and there...i just dont get it. Should i read all this talking, is it relevant to my questions ? i just dont know !! |
If people stop talking you certainly wont learn anything from them! |
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| Rademakers |
| quote: | | Should i read all this talking, is it relevant to my questions ? |
You mean you didn't already? I think you should, if you read between the lines there is a lot of relevant information to be found.
You can also read the diyaudio wiki about horns.
Basically it comes to this; If you do mind cutting a >20 ft^2 gap in your floor next to the wall/corner, make a TL. I doubt there aren't a few dozen threads about designing one.
| quote: | | Is there any calculators tha i can download and enter my sub specs and "fo" wanted, then it returns most of the dimensions to build the horn ?? |
Hornresp, but you need more information. Designing a horn won't be easy anyway.
Wkr Johan |
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| pat allen |
I didnt wanted to sound rude and make every one shut off, i just feel that my question is lost. You can talk as much as you want, i am not the one who can decide about this, but when someone takes its time to start a thread, my thougth are to respect the person and not "hack" the thread with question given into questions.
i read in between the line and there is more info that i need, which is totaly confusing.
I have more questions but i feel that it is going nowhere. Continue to talk in between you guys.
:whazzat: |
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| Cameron Glendin |
| quote: | | i will try the tl for sure asi have all the material to do it, but i would like to get some idea with my Alpine sub spec, what box dimensions it could be for the horn type. |
this sub driver is quite inefficient. 83db 1 watt one meter, If loud is the aim, their are a lot of speakers out there that are much much louder! so if a big bass is important to you, get a different speaker.
Now a 32hz wave is aprox 34 ft, 1/4 of that is ball park 8 ft, a 12 inch pipe, 8 ft long has a volume of aprox 180 litres (does your woofers vas match within x4 ?)
The other serious way of deep deep bass that was mentioned by G.M is the infinite baffle, or extremly large sealed box (up to 4x Vas), compound loaded in a push pull configeration is very nice.
| quote: | | i only have a 12inch one and that is what i want to use, nothing else |
Well a big sounding bass is going to be very hard to do with this speaker, why did you buy it in the first place? does it look pretty?
Both of these designs are very simple to build and get right, they are not rocket science, Bass Horns on the other hand are! speaker efficiency is obviously important for filling a big room, not just a car boot and would suggest that you look for one thats over 90db at 1w @ 1metre or invest in one very expensive amp!
| quote: | | The only thing i understand now is that a horn can get very big if you are not specific enough with your question/spec. |
no, they are just huge, it has nothing to do with specifics
Out of curiosity, what do you expect to hear between 15 to 25 hz, what music or movies do you listen to? big on pipe organ music perhaps?
| quote: | | I didnt wanted to sound rude and make every one shut off, |
well you were and we have! :xeye: |
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| jeff mai |
| quote: | Originally posted by Cameron Glendin
this sub driver is quite inefficient. 83db 1 watt one meter, If loud is the aim, their are a lot of speakers out there that are much much louder! so if a big bass is important to you, get a different speaker. |
I agree with Cameron. In your first post you mention 1000W power handling. This means a big, heavy voice coil and likely lots of power compression at that level.
1000W gets you a 30db increase in SPL. That's 113db/W/m and you'll not get close to that in reality due to power compression. If you start with 98db/W/m sensitivity (there are some 15" drivers that reach this figure), you only need around 30W to reach the same SPL.
High power handling reaches a point of diminishing returns. |
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| AndrewT |
| quote: | | 98db/W/m sensitivity (there are some 15" drivers that reach this figure), |
Yes there are lots of good efficient big drivers that get to that level of sensitivity and even higher.
The one factor they have in common is an Fs of between 30Hz and 50Hz and a few even higher.
It's that efficiency vs size vs bandwidth compromise.
Using these type of drivers is great for conventional bass that rolls off above 30Hz and lower if equalisation is used.
For sub-bass use these big drivers need a lower Fs or lots of post equalisation power.
A low efficiency driver does not necessarily have a wider bandwidth, but most wide bandwidth subs are of necessity less sensitive. |
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| Cameron Glendin |
Free Air Resonance (Fs) : 28Hz
umm his alpine is not that different to some cloth edged hi efficiency |
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| Rademakers |
It's actually very different,
To get 98 dB/W/m the driver has to have an efficiency of 3.98%, this driver has an efficiency of a mere 0,1%.
For a driver with a Fs of 28 Hz to get 3.98%, that would mean Vas has to be 10 times larger (~320 liter/11.9 cu. ft) and Qts 4 times lower (~0.15), than this Alphine.
The Alphine is great for low bass from a relative small enclosure, but if you want it to be loud better stay within 3 ft of it. Just put the opening under your seat ;)
The two most common designs I know, for raising the in-box efficiency would be a bandpass or a horn.
The only horn that's going to get low enough with a relative small mouth would be a Tapped horn.
But if you're up to it you might get nice results with a conventional BLH or FLH.
Wkr Johan |
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| GM |
Greets!
Actually, with a mere 19.1 mm Xmax it can't to any LF of note without some serious box gain since it's excursion limited to ~40 W, so for this reason a tapped horn isn't viable either. As I previous noted it really wants a huge BLH, but I imagine the floor cutout size would be completely unacceptable even if in a corner, so best IMO to return it to the car's trunk where it was designed to be.
GM |
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| Rademakers |
| quote: | | Actually, with a mere 19.1 mm Xmax it can't to any LF of note without some serious box gain since it's excursion limited to ~40 W, so for this reason a tapped horn isn't viable either. |
Ok, you lost me here :xeye:
Excursion limited to ~40 Hz based on what? Isn't a tapped horn providing neccesary gain as does a BLH? Do you expect a full blast at 15 Hz. Do you suggest to get the frequency response flat down to 15 Hz or do you incoorperated roomgain? (No attacks, just wandering).
For certain drivers I've never seen better predicted low-frequency performance than in a tapped horn, for a given size. I might be completely wrong here but I think a BLH and a tapped horn have a lot in common, which makes it all the more suprising you suggest one, while outruling the other.
Wkr Johan |
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| GM |
| quote: | Originally posted by pat allen
hum hum, excuse me guys...
should i start a new thread and let you talk in between you ?
It is very cool that you exchange all this info, but id like the thread to stay focussed on my questions :confused:
i mean, the discusion is going here and there...i just dont get it. Should i read all this talking, is it relevant to my questions ? i just dont know !! |
Greets!
Well, I was trying to 'kill two birds with one stone' by giving you some of what I consider pertinent info by answering Fish Chris's Qs, but judging by your 'thanks, but no thanks' response you just proved the old adage 'no good deed goes unpunished' :(, so I asked Fish Chris to start a new thread and have a moderator transfer all the impertinent posts lest we overload you with too much data.
Hopefully this will occur soon, but in the meantime, what specific Qs do you have that hasn't been answered?
GM |
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| GM |
Greets!
~40 W, not Hz. Yes, it does up to a point, but if you look at TD's tapped horn WP there's gaps in the excursion plot like a too small horn has that will bottom out this driver at relatively modest SPLs down where box gain is most needed. A proper BLH OTOH will have a gain inversely proportional to frequency all the way to the desired F3, but the price you pay is a ~basement sized M = ~0.5 hyperbolic labyrinth with a ~9 Hz Fc.
No, I ignore room gain for the most part because in my experience there's isn't much down low due to a typical home's structure being little more than an acoustic power robbing mechanical damper. I'm sure a home in Quebec is pretty solidly built, so won't be as bad, but assuming it will take up all the 'slack' is a 'crapshoot' at best, so plan for the worst and hope for the best since it's better to attenuate than be caught 'short' IMO.
As always though, YMMV.
GM |
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