I don’t think I’m quite ready to launch into building one just yet, as I am still at the fundamental stage at the moment. Could I substitute 25mm MDF for plywood when I am, as I prefer to work with MDF?
guessing the more bends at the mouth (end where sound expels) is to simulate the more flared end of the horn?
you say the round end is superfluous... I would have thought using a rounded end would help control the box air volume better. I only knocked up that example in SketchUp quickly to capture the idea that MaVo mentioned.
all things being equal and it wasn't undesirable to have a rounded top to the box (say it was easily doable and maybe even desirable) would a more angular box be more technically correct?
the reason I ask is because I don't have a very good understanding of how sound goes around corners and don't want to go to a lot of work for it to be unproductive.
In that case, Silent Screamer, you may not want to build a TH. My impression is there is more "art" needed than other systems (in both wood-stuff and driver selection) and they are less forgiving in the sense that once the glue is dry, you get what you made; unlike BR, for example, where ports can easily be modified, cabinets stuffed, etc.
Ben
Ben
Hey Ben not too worried about the cabinet side of things as I am reasonably skilled with power tools, but I am having trouble trying to work out Hornresp. Wish there was more pictures to the instructions as I don't do all that well with text descriptions.
Yo scream,
Hornresp was intimidating to me as well. The above link is the one i used o get over that.
Then i just began stuffing parameters into it for kicks.
Hornresp was intimidating to me as well. The above link is the one i used o get over that.
Then i just began stuffing parameters into it for kicks.
Hi there : could the more experienced TH-builders propose a few well-suited drivers 12" or 15" for a tapped horn bass/subwoofer ? are the t/s criteria similar for a TQWT ? What kind of MF and HF enclosures work best with a TH woofer of e.g. 40-400 Hz ? This thread is very informative, thanks.
When I said "art," I didn't mean you would have any trouble measuring lumber accurately before cutting it. I meant the difference between theory and actual results.... are sometimes surprising.
Somebody talks about picking suitable drivers. Art or science?
And don't forget, the impressions you get on this forum about THs may not be the same as what you'd hear anywhere else.
Ben
Last edited:
MDF is not as stiff as plywood so requires more bracing than plywood.
Use it if you want to.
Fold patterns can also be what you want, they don't "simulate" anything, but more folds make for more deviation from Hornresp predictions.
If you want to make a rounded top, go ahead, but it it won't affect the sound quality in the low frequency range.
Art
TH come in all shapes and sizes and frequency ranges, and use a wide range of drivers.
If you look at various designs, most list a variety of drivers that will give good results in the particular design.
Although there is a wide variety of speakers that can be used in TH, none will give much more than 2 octaves of smooth response, 40-160 Hz would be about the limit.
If a 400 Hz crossover point is desired, TH are just not a good choice, unless the range was only to be from 100-400 Hz, requiring another sub (and path length time compensation) below.
If you do a lot of stuffing,TH/TQWP range may be extended, but sensitivity is lowered to the point where a FLH or a BR may be a better choice.
Art
@weltersys : I am planning a setup with a middle and a high frequency flared horn plus compression drivers. Since a bass horn is unpractical, I would like to build a tapped horn subwoofer ( lowest possible - 500 Hz). Good drivers : high EPB, low Qts, high fs and Xmax... right ? Is a TH a good addition for flared horns ?
Ben,
Picking a suitable driver for a T.H. uses the same "science" as the choice for any design, the T.S. parameters dictate whether a driver will work well in a given application.
Some degree of "art" comes in regarding suitability for a particular application.
For instance, the Eminence 3015LF or 4015LF work well in TH, but when pushed hard, distort fairly badly because the cone is too light to take the stress without deforming.
For someone using a low output amp, the sensitivity these drivers provide in a TH would be an advantage. For someone wanting really high output from a relatively small box, the cone breakup is a distinct disadvantage.
For someone looking for more clean output, a heavier cone would be selected, which would then require more amp power to achieve the same level as the light cone, but may have 3-6 dB more ultimate level.
Other "artistic" choices may be whether multiple small drivers or isobaric pairs would be advantageous over a larger driver.
Programs like Hornresp or Akabak still allow some degree of "art", but most artists would think it more propeller head pocket pen protector science.
You might remember I was able to find a pair of $5 drivers used as an isobaric pair to replace the Acoustic Research 10" drivers blown in a TH test, were it not for Hornresp, I would not have considered those drivers viable.
As it turned out, the cheap drivers in a TH work well from 20-60 Hz, filling in below the other BR subs in my shop.
Art
Hi Chano,
A TH is suitable as a subwoofer in the range below 100Hz (generally speaking). If you are looking for a broad band woofer (Post #70: "...lowest possible - 500 Hz") you would be looking at a different enclosure.
Regards,
A TH is suitable as a subwoofer in the range below 100Hz (generally speaking). If you are looking for a broad band woofer (Post #70: "...lowest possible - 500 Hz") you would be looking at a different enclosure.
Regards,
Thanks guys some really useful posts in the last couple of pages (that Hornresp link is very helpful) and I think it will help any novice trying to get a good start in TH design.
TH being suitable for 40-160Hz sounds like I am on the right enclosure track, as that is the target frequency I am chasing, 20Hz-80Hz would be even nicer but it sounds like this is the right enclosure to try it with.
The more I think about it a tall thin cabinet is not such a bad shape to go with as a smaller floor foot print probably has a higher WAF, and stop the temptation of things being put on top of the speaker that might happen with something more cube shaped.
I have been playing with a somewhat different build concept to what many of you are currently using.
Using a router I am currently designing some speakers that are built in slices (think a loaf of bread) but instead of having to screw all of the internal boards into place I can cut them all as part of the box (think smiley face cut into each slice of bread)
Using templates to ensure uniformity, I could potentially make the cuts of any shape I want, and still create a layered structure not unlike the plywood, but with wider strips of material (18mm-25mm strips).
Currently I am only looking to do this on a smaller cabinet where waste would be minimal, but nothing stops it being scaled up provided you don’t mind chewing up a few sheets.
Using an 8’ x 4’ sheet (2400mm x 1200mm) should be able to get three slices per sheet, maybe five or six sheets per cabinet? Cost of regular plywood (nothing flash) is about 2.5 times the cost of MDF, so maybe $150 - $180 a cabinet for MDF.
TH being suitable for 40-160Hz sounds like I am on the right enclosure track, as that is the target frequency I am chasing, 20Hz-80Hz would be even nicer but it sounds like this is the right enclosure to try it with.
The more I think about it a tall thin cabinet is not such a bad shape to go with as a smaller floor foot print probably has a higher WAF, and stop the temptation of things being put on top of the speaker that might happen with something more cube shaped.
I have been playing with a somewhat different build concept to what many of you are currently using.
Using a router I am currently designing some speakers that are built in slices (think a loaf of bread) but instead of having to screw all of the internal boards into place I can cut them all as part of the box (think smiley face cut into each slice of bread)
Using templates to ensure uniformity, I could potentially make the cuts of any shape I want, and still create a layered structure not unlike the plywood, but with wider strips of material (18mm-25mm strips).
Currently I am only looking to do this on a smaller cabinet where waste would be minimal, but nothing stops it being scaled up provided you don’t mind chewing up a few sheets.
Using an 8’ x 4’ sheet (2400mm x 1200mm) should be able to get three slices per sheet, maybe five or six sheets per cabinet? Cost of regular plywood (nothing flash) is about 2.5 times the cost of MDF, so maybe $150 - $180 a cabinet for MDF.
That link Simple Tapped Horn Tutorial using Hornresp - AVS Forum does not shown the diagram and other graphics.
How do we access them?
2octaves is about the max you can expect from a TH.
Most TH can manage 1.5octaves and to get up to 1.7octaves most will require a lot of EQ (both passive and active) to attenuate the ripples that seem to be inevitable at the upper end of the required octave range.
40 to 160Hz and 20 to 80Hz will be very difficult to achieve from a TH.
How do we access them?
2octaves is about the max you can expect from a TH.
Most TH can manage 1.5octaves and to get up to 1.7octaves most will require a lot of EQ (both passive and active) to attenuate the ripples that seem to be inevitable at the upper end of the required octave range.
40 to 160Hz and 20 to 80Hz will be very difficult to achieve from a TH.
Last edited:
Show us the Hornresp input data and we might be able to identify what is nearly unique in your example.
How much EQ has been added to get that response?
How much EQ has been added to get that response?
That's the last measured response of my POC TH with the "dogfood duct" mod. No EQ was added. The duct basically eliminated the notch at the upper end of the TH's passband and extended it a bit as you can see. It might be possible to get even better results by emulating the system in AkAbak and adjusting the length, width and location of the duct to flatten the response even further.
For more information, see The Subwoofer DIY Page v1.1 - Projects : "Proof of Concept #2"
Looks like you have proved my comment.
You have done it, but many never get anywhere near your posted results. You also used EQ, the passive variety.
Getting back to the simple nature of the thread (as this thread is for the complete newbie to TH) how much is an octave?
I know what an octave is in singing terms, but what does that look like in frequency response and why (if it can be explained simply) is it limited to 2 octaves?
The Hornresp post helped a bit, but I failed to see how to get a drvier of my choosing to anywhere near remotely flat.
I know what an octave is in singing terms, but what does that look like in frequency response and why (if it can be explained simply) is it limited to 2 octaves?
The Hornresp post helped a bit, but I failed to see how to get a drvier of my choosing to anywhere near remotely flat.
- Status
- Not open for further replies.