2012-05-21T03:45:46Z Claes Martinsson Copyright 2012, Claes Martinsson SPHPBLOG
The THAM15 (187 l) and THAM12 (96.25 l) :


The THAM10 (60.75 l) and THAM12 (96.25 l) :


And just for fun, why not compare David and Goliath :)
The THAM6 (42.18 l) and THAM15 (187 l) :


If I could figure out how to overlay the THAM10, 12 and 15 graphs you would see that these is a method to the madness, each models differs by approx 10Hz in response depth.

And finaly a comparison in size to a fairly standard 218 subwoofer, choosen for it's comparable sensitivity and familliar size :


THAM series direct links :

THAM10

THAM12

THAM15

THAM6

TPAM10HT

Simply choose, print, build and be amazed :)

oh, and yes, there is something else in the works...



This is still very much a work in progress, just thought you might like a preview, a teaser if you will, if this becomes a official THAM design remains to be seen, so no promises.
]]> http://www.martinsson.cc/blog/index.php?entry=entry120331-124819 2012-03-31T00:00:00Z 2012-03-31T00:00:00Z
Once again Johannes Rodin is to blame for yet another new THAM design seeing the light of day, his first words where "- it's tuned to low and the enclosure is to big" but eventually he came around to seeing it my way :)

If you csn not find your driver below and have questions like "will this driver work?" then please try yourself using the data provided above and simulate it using hornresp, if it works, please let me know, all the info you need to find out if your driver will work is already provided here.

The drawings will be updated, and the original Beyma 12LX60 will be added to the simulations, I have seen it and it looks just fine.

The designproocess :


Frontview :


Internal dimensions :


Braces and their postions :


Driver Baffle (note that the cutout is driver dependent) :


Assembly control dimensions :


Hornresp dimensions :


Default driver example Beyma 12LX60V2 :


hornresp simulation input data :


Flat on open ground 1W 1m Beyma 12LX60V2 :


Along a wall 1W 1m Beyma 12LX60V2 :


In a corner 1W 1m Beyma 12LX60V2 :


Max SPL Beyma 12LX60V2 :


Groupdelay Beyma 12LX60V2 :


System volume :


Phase :


Impedance :


Cone excusrion :



Please note that I do not judge the following simulations, this should be left to the potential DIY'er, but it goes without saying that some simulations shows better results then others.

Some designer notes - This design prefers high BL (about 20 or higher) and low QTS, but i guess thats a given to anyone visiting this page, right!* :)

*/ I try to make it a point that not only hell bent speaker nerds should be able to DIY a decent tapped horn.

Other driver examples all simulated in 1PI environment :

B&C 12PS100 :


B&C 12NDL76 :


B&C 12NW76 :


B&C 12BG100 :


Beyma 12P80Nd :


Faitalpro 12FH500 :


Faitalpro 12FH510 :


Fatialpro PR300 :


Faitalpro 12HP1020 :


RCF MB12N407 :


RCF LF12G301 :


RCF LF12N301 :


RCF LF12N401 :


18sound 12NLW9300


18sound 12W500 :


18sound 12W700 :


Beyma 12LX60 :


BMS 12N804 :


BMS 12N630 :


Eminence Kappalite 3012LF :


Eminence Definimax 40012HO :


JBL 2204H :


JBL 2206H :


JBL GTi1200 :


JBL 2020H :


Precision Devices PD 121 :


Precision Devices PD 122 :


Precision Devices PD12SB30 :


Precision Devices PDN12MH25 :


And finaly some build pictures that i got sent to me :



]]> http://www.martinsson.cc/blog/index.php?entry=entry120315-210219 2012-03-15T00:00:00Z 2012-03-15T00:00:00Z


It just so happened that I had a couple of JBL 2386 2" horns collecting dust in the storage room, I realized this was not quite an obvious match, rather the opposite in fact.



Well, needless to say this unholy union needed some tweaking...



This did the trick, these horns are very fun to listen to, the resolution they provide crossed over at 140Hz to the THAM6 residing under the tv rack is just amazing, although the frequency response is not exactly "ruler flat" :)



Not scoring very high in the WAF category, but then again, I don't have that problem :)



They look like good old stadium horns they use at the tracks :)



Not that far off actually, these horns, the JBL 2386's where actually intended for clustering applications in arena type environments, their dispersion pattern being 40x20 (HxV).



So they sound nice and clear with great resolution down to approx 300Hz, they are more then loud enough for apartment use, and they cost me a whooping 230sek each :)
]]> http://www.martinsson.cc/blog/index.php?entry=entry120110-222118 2012-01-10T00:00:00Z 2012-01-10T00:00:00Z
As usual I got a lot of help from my friend Johannes Rodin who also helped me out on the THAM series designs.

The TPAM10HT design principle, lovingly referred to as "tapped pipe" allows for relatively compact outer dimensions while still reaching it's goal of simulated in room 20Hz reproduction.

TPAM10HT contains a lot of compromises in order to reach it's performance with approx 80 liters of system volume, one of which is the driver depth (max 120mm), the other is the sound pressure level, even if i believe it should be sufficient for most users.

The TPAM10HT has been simulated in all positions and with two drivers i found to be of interest, but there might be more suitable drivers out there.

Please note that I can't answer questions regarding the suitability of these other drivers, no disrespect intended but I simply do not have the time, instead please use hornesp. and the data provided here to find your best candidate.

This is the TPAM10HT :









The cutout geometry shown in the drawings above is tailored for this driver :

Product Line: Peerless Gold
Model Number: XLS-P835028

Be aware of this if you choose to go for another driver.

TPAM10HT system volume and principle :


Simulation results for the Peerless XLS-P835028 at 1W & 1m :

XLS-P835028 When positioned in a corner:


XLS-P835028 When positioned along a wall:


XLS-P835028 When positioned freely on the floor:


XLS-P835028 Electrical impedance:


XLS-P835028 Cone excursion:


XLS-P835028 Group delay:


XLS-P835028 Impulse response:



I also found the B&C 10NW64 to be a candidate, below you will
find the simulation results for the B&C 10NW64 at 1W & 1m :


B&C 10NW64 When positioned in a corner:


B&C 10NW64 When positioned along a wall:


B&C 10NW64 When positioned freely on the floor:


B&C 10NW64 Electrical impedance:


B&C 10NW64 Cone excursion:


B&C 10NW64 Group delay:


B&C 10NW64 Impulse response:


These are my recommendations for now, they will both fit in the TPAM10HT but please note that the cut out geometry specified in the drawings are tailored for the Peerless XLS-P835028, so some adjustments might be necessary if you go for the B&C 10NW64.

If the driver of your choice (outside of those above) can't be fitted within the 120mm depth restriction the box may be widened, but doing this will void any of the results above and I would strongly recommend a simulation prior to build.

This design has not been built and tested in real world conditions yet, results will be posted when this has been done.

Finally some build pictures :

]]> http://www.martinsson.cc/blog/index.php?entry=entry110905-211334 2011-09-05T00:00:00Z 2011-09-05T00:00:00Z
This is my suggestion for a very compact, lightweight and capable 10" loaded tapped horn which should provide well from 50Hz and up in real world conditions.

Many thanks to Johannes Rodin for providing good ideas and valuable insight, his help in my designs to date (THAM6, THAM15 and now THAM10) is a big part of the end result.

This is the THAM10 :


Part 1 of the drawings



Part 2 of the drawings



The hornresp input data


The cone excursion at 1W (and approx. 100dB output)


The SPL graph in 2PI (halfspace, flat on open ground) and 1W.

The following simulatons are made in a 1PI environment, I will not judge these simulations, that is best left to the potential DIY'er.


Loaded with the B&C 10MD26 and placed along a wall, 1W, 1m.


Loaded with the B&C 10PS26 and placed along a wall, 1W, 1m.


Loaded with the B&C 10HPL64 and placed along a wall, 1W, 1m.


Loaded with the B&C 10NDL64 and placed along a wall, 1W, 1m.


Loaded with the Beyma 10G40 and placed along a wall, 1W, 1m.


Loaded with the Beyma 10LW30N and placed along a wall, 1W, 1m.


Loaded with the RCF L10-750YK and placed along a wall, 1W, 1m.

My previous designs all provided approx. 10Hz lower low frequency drop off corner in reality then the simulations showed, and with that in mind I have no difficulties thinking this design should be capable of useful response from 50Hz.

They should be (must be) processed with a low frequency cut of filter set at minimum 40Hz, preferably 50Hz, and with a slope of 24dB/Oct for safe operation at higher levels, the upper cross over point may be set as the user feels appropriate at each given situation.

Designed with the B&C 10NW64 in mind, a lightweight neodynium woofer, these small boxes should be easy to handle, and easy to transport, the amount of power the THAM10 will safely handle is yet to be determined by real world use.

Intended for use as bass speakers in small live acts where sub bass is not required, and space is limited, they should be able to surprise in a positive way with regards to sound pressure level given their size and weight.

Questions regarding other suitable drivers will not be answered, try simulating them yourself in hornresp using the data provided above.

BUILD PICTURES :









]]> http://www.martinsson.cc/blog/index.php?entry=entry110306-224208 2011-03-06T00:00:00Z 2011-03-06T00:00:00Z
PLEASE NOTE THAT THE FOLLOWING IS A DEVELOPMENT RELEASE ONLY.

Useful response from 50Hz, I'll let the pictures explain the rest.









]]> http://www.martinsson.cc/blog/index.php?entry=entry110205-183805 2011-02-05T00:00:00Z 2011-02-05T00:00:00Z
PLEASE NOTE THAT THE FOLLOWING IS A DEVELOPMENT RELEASE ONLY.



Adding a reflector in the front chamber to reduce possible turbulence, and adding a 12mm distance plate beneath the driver to secure that the cone newer comes in contact with a hard surface, this may also reduce compression risks.]]> http://www.martinsson.cc/blog/index.php?entry=entry110130-205617 2011-01-30T00:00:00Z 2011-01-30T00:00:00Z
I belive it would look something like this :



The details remains to be sorted out, as is the simulation, but it seems to amount to a seriously capable design in a format that mimics the usual size of PA bass enclosures.

PLEASE NOTE THAT THE FOLLOWING IS A DEVELOPMENT RELEASE ONLY.]]> http://www.martinsson.cc/blog/index.php?entry=entry110130-204135 2011-01-30T00:00:00Z 2011-01-30T00:00:00Z
PLEASE NOTE THAT THE FOLLOWING IS A DEVELOPMENT RELEASE ONLY.

Overview:


Loaded with the B&C 10NDL64 :


Loaded with the B&C 10NW64 :


Loaded with the B&C 10MD26 :


The hornresp input window


All simulations in 2PI, 1W, same box different drivers.

Let's see hoe far we can go with a 300x450x500mm box :)

next up is this, same outer dimensions, different folding :



With some dimensions :


In 2PI loaded with the B&C 10NW64 :


In 0,5PI same driver, rather impressive for it's size :


The input window data :
]]> http://www.martinsson.cc/blog/index.php?entry=entry110126-222217 2011-01-26T00:00:00Z 2011-01-26T00:00:00Z
This is a work in progress, and this is just to show you that I'm still active, and perhaps also what I'm thinking of.

PLEASE NOTE THAT THE FOLLOWING IS A DEVELOPMENT RELEASE ONLY.





The driver chosen in this case is th B&C 10PS26, again please note that this is not anything more then a thought and the room for improvement is yet to be explored.

There are better drivers out there, and the sims should be in 2PI, nothing else is valid, so take this with a pinch of salt.]]> http://www.martinsson.cc/blog/index.php?entry=entry110126-065426 2011-01-26T00:00:00Z 2011-01-26T00:00:00Z