THAM15 - a compact 15" tapped horn

I ordered a pair of THAM15 boxes from a Swedish firm a few years back and put a pair of 15PS100 in them. I used them for our wedding party and then never really did a lot else. But now me and a friend are putting together a small gathering in a few weeks, so we started playing them a bit more. Just going back and reading about people commenting that there's a lot of "punch", I'm starting to think something is wrong with my two boxes. Just trying right now with one box (open air) being driven through a t.amp 2400 MK-X in bridge mode (so about 2400w @ 8 ohm), being fed with a 2496 Ultracurve at LP 48db 40hz / HP 48db 140hz it sounds pretty muddy and lacks any real punch. I can't really open the boxes to check the internal construction since they are glued, but it feels like it's far from how impressed other people are with them.

I'm definitely not faulting the design, but I'm trying to figure out what could possibly be wrong. Maybe one of the Swedish people who know the THAM boxes would be willing to come visit and try to help with diagnosis? I could definitely pay for travel and time since I'm really at a loss here.
 
I've got a couple of old 15" ATC PA100-375 BLC drivers I'm thinking of for a THAM15 project. It's really a budget build since I was given the drivers for free, but they seem to suite a horn best. This could be a fun project!

I'm simply wonder if I've filled the parameters correct? Hornresp should be set to TH mode and 2,0 x Pi for Tham15 right?

Should I enter or change any particular settings to make the driver suite the enclosure better? Goal is low frequency before SPL. Can I do anything to push it to the 30hz area?

Btw, I don't understand why I can't see the FR and Tal parameters. Is it because I'm using a newer version of Hornresp?
 

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I've got a couple of old 15" ATC PA100-375 BLC drivers I'm thinking of for a THAM15 project. It's really a budget build since I was given the drivers for free, but they seem to suite a horn best. This could be a fun project!

I'm simply wonder if I've filled the parameters correct? Hornresp should be set to TH mode and 2,0 x Pi for Tham15 right?

Should I enter or change any particular settings to make the driver suite the enclosure better? Goal is low frequency before SPL. Can I do anything to push it to the 30hz area?

Btw, I don't understand why I can't see the FR and Tal parameters. Is it because I'm using a newer version of Hornresp?

That’s for a polyfil in a sealed Rear chamber, which you can’t have in a tapped horn. In ‘loudspeaker wizard’ mode you can do the ‘stuffing/filling in the S and L segments.

If you remove L12 (0.1cm) and create a VTC/AtC you can morph this into a lower Hz type of enclosure but it gets big really quick...

I dunno if a THAM gets much lower than 50(?), but part of its charm is in that upper bass regions unique ‘punch or smack’ in delivery I think? Like a ROAR or similar seem to have as well.
 
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The THAM and the ROAR series are sound character related to an extent, this stems from the same people being involved in the designprocess and the balancing of the peoperties, we try to avoid tuning to low and instead balance for decent LF performance and a more puchy, livley sound.

However, if you look at the impedance signatures you will spot the difference, the ROAR shows one additional impedance peak, which in some regards elevates it from a 6'th order design such as the THAM to an 8'th order design, but this is not the only difference, size and coupling area is also increased for each given driver category, rendering the ROAR series quite a bit more capable.
 
I don’t know how close I’ve gotten to the THAM or ROAR sound ‘exactly’, but the similar yet uniquely different layouts of all of them I’ve used or currently have seem to share one thing in common to my ears/chest/face. And it’s quite spectacular!?
 

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I've got a couple of old 15" ATC PA100-375 BLC drivers I'm thinking of for a THAM15 project. It's really a budget build since I was given the drivers for free, but they seem to suite a horn best. This could be a fun project!

I'm simply wonder if I've filled the parameters correct? Hornresp should be set to TH mode and 2,0 x Pi for Tham15 right?

Should I enter or change any particular settings to make the driver suite the enclosure better? Goal is low frequency before SPL. Can I do anything to push it to the 30hz area?

Btw, I don't understand why I can't see the FR and Tal parameters. Is it because I'm using a newer version of Hornresp?

You are not building an exponential horn. You need to change the segments from EXP to PAR. You are going to physically build a parabolic horn.
 
You are not building an exponential horn. You need to change the segments from EXP to PAR. You are going to physically build a parabolic horn.

This is a very real statement! One that’s hard to make sure and realize if trying to make 3 PAR segments emulate a single EXP simmed. Tricky and a challenge to get good. Mediocre is what kinda luck I have with that. Not horrible but never perfect.
 
I agree. Would love to see what you come with Chris.



I think in today's world you need 30hz. The average person knows this stuff now and expect it. Look at all the "when the bass drops" memes etc. My Keystone does half decent.



Every now and then I think of doing Bateman's TH50. 30hz in spades.
 
First build Tham 15"

Newb here. I hope this is an appropriate place to post. I just completed my first sub build based on these plans (THAM 15), although I live in the US so had to use 3/4 inch 11 ply birch and convert as best i could. So far I have loaded it with an 8ohm JBL M115-8A which is all I had lying around powered by one channel on a Behringer (sorry?) EP2000 and running through a DBX Driverack Venu360. It sounds pretty incredible to me! My question is, and this probably demonstrates my level of understanding-- how do I determine the length of the horn so I can calculate the proper delay time to pair it with some 12" active tops? I have messed around with doing it by ear as well and I am aware of expensive programs like SMAART that can help me with that and also that the DBX can do it automatically with an RTA mic, but i think the wind/ city noises can make that difficult. just wondering if anyone had any insight on this or can point me towards a good resource. I don't really understand if it is the walls of the horn I should be measuring or a point right in between or what point I should measure off of the driver hole baffle? I know it wont be perfect doing it this way but I'm looking for a starting point to approximate. Right now 8.5-9 feet seems like the range. am I way off? Thanks for reading this far!
 
The THAM and the ROAR series are sound character related to an extent, this stems from the same people being involved in the designprocess and the balancing of the peoperties, we try to avoid tuning to low and instead balance for decent LF performance and a more puchy, livley sound.

Thank you!


Tom Danley have TAPPED HORNS from mini 12" to XL 18"
-TH mini 129dB 135 dB peak from 700W (maybe an B&C) 48 Hz - 200 Hz - 3 dB from a 24 x 15 x 24 inches enclosure - 140 liters

then (because is commercial) they put an low bass but with lower power (maybe to convince clients to buy next TH115)

-TH112 126dB 132 dB peak from 400W (maybe B&C) 33 Hz - 200 Hz - 3 dB from 336 liters

-THmini15 132dB 138 dB peak from 1.000W (maybe B&C) 50 Hz - 200 Hz - 3 dB
from 212 liters

-TH 115 The Workhorse of the TH line 133dB 139 dB peak from 1.000W (maybe B&C) 38 Hz - 200 Hz - 3 dB
from 420 liters

then TH118 XL 134dB 140 dB peak from 1.700W (maybe B&C 18SW115 or B&C 18IPAL or B&C 18DS115) 38 Hz - 200 Hz - 3 dB
from 732 liters

this is about danleysoundlabs.

Another company is Lambda Labs.

Conclusion: Danley have some customized project for enclosures, tuned and tested, best fit for mid-high topers.

I want to build a cluster of tham 12 with B&C 12PS100, for the beginning I wil start with a single enlosure, then another 3, then another 4. so in the end I want to have 8x THAM12 .

For amplifier I will use Chinese clone FP10.000Q (class TD 4x2100W at 4 ohms -thats why I will go with a better trusted 700W rather than another woofers with overclocking 1.000W).

any better idea?
 
You could use the BOXPLAN-THAM workbook from the site below for that purpose.

The Subwoofer DIY Page - Horn Folding

can you make me a design for B&C 12PS100? A bigger enclosure? how can I design a THAM that get a little lower for this driver? maybe from 45 Hz to 90 Hz instead 50 Hz to never mind 200Hz.

B&C 12PS100 have Fs 44 Hz

my personal email adcipisound003@gmail.com if anyone can send me the excel with a custom project. But lets make it here, to talk along the perfect THAM12 for mobile DJ and live bands.

For me, perfect subwoofer for mobile DJ/Band means scalable like LEGO, multiple enclosures, easy to carry, punchy, tuneful, fast and precise bass.


Thank you all !!!!!!!
 
so, for 179 liters I will get just 120dB @34Hz and just maximum 350W because the 12PS100 will touch the Xmax? :confused:

tHAM 12 have a volume at around 100 liters (55x35x52 cm external). Is almoust half of the size (179 liters is ~double)...


what about something between 100 liters and 179 liters, something a little taller but tuned to accept 700 W and a safe diaphragm displacement ? or is not possible?

who can tell me if a cluster of 4x tham 12 will get louder or will get a little lower too? what about 8x cluster on the floor, centered in straight line in front of the stage? do I get some low frequencies if I put more?

Do I get directivity for bass in 8x cluster?

I just want to obtain the best result.

Or just with 15" is possible to achieve the perfect subwoofers ?????
( remember :) scalable like LEGO, multiple enclosures, easy to carry, punchy, tuneful, fast and precise bass... )

Who test clusters? who compare 12" vs 15"? mini enclosure versus extended enclosure?

Thank you again!:)