Hi
I am thinking of horn loading my set of TAD TM-1201s in a front horn. Probably in a 150 Hz horn and then cross at about 250-300Hz.
Has anyone tried this or would it be better just to use it as a direct radiator?
Are there any commercial horns in that size that suits the TM-1201?
Many thanks,
Jeppe
I am thinking of horn loading my set of TAD TM-1201s in a front horn. Probably in a 150 Hz horn and then cross at about 250-300Hz.
Has anyone tried this or would it be better just to use it as a direct radiator?
Are there any commercial horns in that size that suits the TM-1201?
Many thanks,
Jeppe
Contraindicated
A properly designed horn will provide a decade of usable bandwidth.
You will need a horn of comparable dimensions to provide loading down to a 2 meter wave length.
The primary purpose of such a horn, is to cover the speech range (200-2000 Hz) without bifurcation
There are very few manufacturers that provide, medium format, speech-range horns. Of these the following are notable:
Funktion One (Tony Andrews)
FUNKTION-ONE : OFFICIAL WEBSITE
Community Light & Sound (Bruce Howze)
Community Professional Loudspeakers
This JBL technical tech note may be of some help.
http://www.jblpro.com/catalog/support/getfile.aspx?doctype=3&docid=201
Only in a listening space, a magnitude larger, will use of such a horn be beneficial.
Regards,
WHG
A properly designed horn will provide a decade of usable bandwidth.
You will need a horn of comparable dimensions to provide loading down to a 2 meter wave length.
The primary purpose of such a horn, is to cover the speech range (200-2000 Hz) without bifurcation
There are very few manufacturers that provide, medium format, speech-range horns. Of these the following are notable:
Funktion One (Tony Andrews)
FUNKTION-ONE : OFFICIAL WEBSITE
Community Light & Sound (Bruce Howze)
Community Professional Loudspeakers
This JBL technical tech note may be of some help.
http://www.jblpro.com/catalog/support/getfile.aspx?doctype=3&docid=201
Only in a listening space, a magnitude larger, will use of such a horn be beneficial.
Regards,
WHG
You will find opinions here based on horn resp sims ,that TM 1201 is not really suitable for horn loading. Do a search on forums.
Sorry for the late reply!
whgeiger: Could you post a direct link to the horn you think you be suitable as i'm not able to find it 🙁
limono: Could you also provide a link? I think i have read just about anything about the 1201, but not that its best used as a direct radiator.
Many thanks for your replys,
Jeppe
whgeiger: Could you post a direct link to the horn you think you be suitable as i'm not able to find it 🙁
limono: Could you also provide a link? I think i have read just about anything about the 1201, but not that its best used as a direct radiator.
Many thanks for your replys,
Jeppe
If you want a speech range horn, to match the TD-1201 you will have to design it yourself.
This would be a non-trivial, although a possible exercise. I have already given you guidelines for doing that.
Parameters for this driver follow:
Nominal Impedance 8 Ohm.
Lowest Resonance Frequency (Fo)52 Hz.
Frequency Range 150-4500 Hz.
Rated Input Power 150 W.
Maximum Input Power 300 W.
Sound Pressure Level 100 dB/W (1m).
Total Magnetic Flux 324.000 Mx.
Magnetic Flux Density 14.500 G.
Recommended Bandpass Filter 200 - 3.000 Hz.
Recommended EnclosureOver 11 liter.
Effective Piston Diameter 260,0 mm.
Baffle Opening 276,0 mm.
Mounting Dimensions 293,0 mm.
Weight 11 kg.
Dimensions (diameter x depth) 318 x 110 mm.
Theile-Small Parameters
sd - Piston Area 0,0531 Sq M.
Revc - DV Voice Coil Resistance 5 Ohm.
Levc - Voice Coil Inductance 1kHz (mH) 0,68.
BL - Flux Density (TM) 26,0.
Vas - Equivalent Acoustic Volume (Liter) 63 liter.
Cms - Mechanical Suspension Compliance (x 10-4 m/N) 1561.
Mms - Mechanical Mass of Cone and Free Air Load6 g.
Mmd5 g.
Fs - Free Air Resonance Frequency 52 Hz.
Qms - Mechanical Q Factor1,43.
Qes - Electrical Q Factor0,15.
Qts - Total Q factor0,14.
Xmax - Max Linear Peak Excursion (O-P)2,5 mm.
Pmax - RMS Thermal power Limit300 W.
no - Relative Efficiency5,54 %.
Vd (cm²)1,33.
Max. Excursion Before Damage (P-P)22,
Run some simulations using Horn-Response to see where it takes you.
Horn throat Sd/2, length > c/(4*Fc), Mouth perimeter, = approx. c/Fc
Otherwise a simple sealed enclosure, with low-end equalization will do, unless your listening space is huge. Sensitivity of this driver is high.
As this is a low-Q driver, with limited xmax, c/o at >200 Hz.
Regards,
WHG
P.S.
Here's the SPL plot from Horn-Response (McBean) with the TAD TM-1201 on a cosh horn.
This would be a non-trivial, although a possible exercise. I have already given you guidelines for doing that.
Parameters for this driver follow:
Nominal Impedance 8 Ohm.
Lowest Resonance Frequency (Fo)52 Hz.
Frequency Range 150-4500 Hz.
Rated Input Power 150 W.
Maximum Input Power 300 W.
Sound Pressure Level 100 dB/W (1m).
Total Magnetic Flux 324.000 Mx.
Magnetic Flux Density 14.500 G.
Recommended Bandpass Filter 200 - 3.000 Hz.
Recommended EnclosureOver 11 liter.
Effective Piston Diameter 260,0 mm.
Baffle Opening 276,0 mm.
Mounting Dimensions 293,0 mm.
Weight 11 kg.
Dimensions (diameter x depth) 318 x 110 mm.
Theile-Small Parameters
sd - Piston Area 0,0531 Sq M.
Revc - DV Voice Coil Resistance 5 Ohm.
Levc - Voice Coil Inductance 1kHz (mH) 0,68.
BL - Flux Density (TM) 26,0.
Vas - Equivalent Acoustic Volume (Liter) 63 liter.
Cms - Mechanical Suspension Compliance (x 10-4 m/N) 1561.
Mms - Mechanical Mass of Cone and Free Air Load6 g.
Mmd5 g.
Fs - Free Air Resonance Frequency 52 Hz.
Qms - Mechanical Q Factor1,43.
Qes - Electrical Q Factor0,15.
Qts - Total Q factor0,14.
Xmax - Max Linear Peak Excursion (O-P)2,5 mm.
Pmax - RMS Thermal power Limit300 W.
no - Relative Efficiency5,54 %.
Vd (cm²)1,33.
Max. Excursion Before Damage (P-P)22,
Run some simulations using Horn-Response to see where it takes you.
Horn throat Sd/2, length > c/(4*Fc), Mouth perimeter, = approx. c/Fc
Otherwise a simple sealed enclosure, with low-end equalization will do, unless your listening space is huge. Sensitivity of this driver is high.
As this is a low-Q driver, with limited xmax, c/o at >200 Hz.
Regards,
WHG
P.S.
Here's the SPL plot from Horn-Response (McBean) with the TAD TM-1201 on a cosh horn.
Attachments
The above, 5 or 6g, is wrong. It's from published datasheet I know, but it's wrong.
Times ten is more like it. And you'll have a much more declined FR.
Have you built (of found) such a horn for this driver and given the combo a listen (or measure)?
Guess what? I have 😉
Guess what? I have 😉
Limono, you are so right. It wasn´t so long ago we discussed the subject here. This driver is not suited for horn use.
Could you elaborate?
I though you where happy with the result:
http://www.diyaudio.com/forums/multi-way/125349-3way-horn.html
Thanks
I am curious as to why it is not suitable. The Qts and Qes are very low, which is desirable in a driver for horn loading, as far as I know. Which parameter makes this driver unsuitable? Please educate me or show me the thread about that. The response shown above in Hornresp looks really great to me.
Hi pos,
It's a shame that gorgeous looking mid horn is not a proper horn I'd say, as dirkwright has mentioned above. Rather, it's more like a wave guide shape of OB 😱 That project was finished in a tight schedule, not enough time for trial and error, sigh... But what is done is done, I still have to admit that's my desgin, my failure.
Eventually it was made like that, oh well. The short length and rapid flare don't provide optimum load and the big throat gives problem to the higher end. So the result is narrow usable range with little acoustic gain.
The whole system is supported by the HF and LF horns, with the mid filling the 200-800Hz or so (and some help from higher gain of the driving amp). I forget the exact numbers of xover setting, anyway the mid covers only 2 octaves, or slightly more. I think it's not a good configuration for a 3-way.
Maybe the only good thing is, maybe, again, maybe it provides some wave guide function, so the directivity from high to low of the whole system could be maintained or at least a smoother transition in the critical zone. I'm not sure...
Faulty as it is, the whole system is still very listenable, enjoyable, or even shockingly good in some materials. What a team work in covering the weak point!
It's a shame that gorgeous looking mid horn is not a proper horn I'd say, as dirkwright has mentioned above. Rather, it's more like a wave guide shape of OB 😱 That project was finished in a tight schedule, not enough time for trial and error, sigh... But what is done is done, I still have to admit that's my desgin, my failure.
Eventually it was made like that, oh well. The short length and rapid flare don't provide optimum load and the big throat gives problem to the higher end. So the result is narrow usable range with little acoustic gain.
The whole system is supported by the HF and LF horns, with the mid filling the 200-800Hz or so (and some help from higher gain of the driving amp). I forget the exact numbers of xover setting, anyway the mid covers only 2 octaves, or slightly more. I think it's not a good configuration for a 3-way.
Maybe the only good thing is, maybe, again, maybe it provides some wave guide function, so the directivity from high to low of the whole system could be maintained or at least a smoother transition in the critical zone. I'm not sure...
Faulty as it is, the whole system is still very listenable, enjoyable, or even shockingly good in some materials. What a team work in covering the weak point!
Actually , it's a very vogue description. So whats wrong with this wave guide ? Doesn't measure good , doesn't sound good and if , what's precisely you're discontent about? I had it in Azura 202Hz horn with 8" throat doing 200hz-500hz on the floor and it was very good and was spacious/imaging like a mofo. Quite shockig what a round upperbass can do with a space.
OK, as said, the whole system is working well. Everyone seeing and hearing that system is happy except me myself.
The speaker is big enough so one can hear each unit separately if being close enough. Usually it's no fun doing so, but it reveals something.
Listening to the HF unit, it's thin sounding (of course), but very clean, not harsh. (And it can play deafening loud with 0.7w tube amp in the later trial). Listening to the LF unit, it's very pure bass, thundering, rumbling, but then it's clean, too, becuase the start and stop are very well defined, even with clear 'edges'.
Listening to this mid unit, it sounds muffled, lifeless in it's range, kind of being covered by something in front of it. And it needs quite a lot more gain to be balanced with the other two units. Listening at the rear (there's no back chamber), those "unhealthy" effects are gone. It's opening up, clean, and energetic, only slightly quieter than the front overall. (forturnately there's still a little 'gain' in front...)
By the reasons above, I call it a failure. That's maybe too strong a word. And the 'impressions' are not thorough at all, I know. Overall in room response is actually very good in a pretty large area. Maybe helped by the "WG" function of that 'horn' -- no good in near field but better far out (?)
Nevertheless, it can be better than that. I believe. That is not the best way to use that excellent driver.
The speaker is big enough so one can hear each unit separately if being close enough. Usually it's no fun doing so, but it reveals something.
Listening to the HF unit, it's thin sounding (of course), but very clean, not harsh. (And it can play deafening loud with 0.7w tube amp in the later trial). Listening to the LF unit, it's very pure bass, thundering, rumbling, but then it's clean, too, becuase the start and stop are very well defined, even with clear 'edges'.
Listening to this mid unit, it sounds muffled, lifeless in it's range, kind of being covered by something in front of it. And it needs quite a lot more gain to be balanced with the other two units. Listening at the rear (there's no back chamber), those "unhealthy" effects are gone. It's opening up, clean, and energetic, only slightly quieter than the front overall. (forturnately there's still a little 'gain' in front...)
By the reasons above, I call it a failure. That's maybe too strong a word. And the 'impressions' are not thorough at all, I know. Overall in room response is actually very good in a pretty large area. Maybe helped by the "WG" function of that 'horn' -- no good in near field but better far out (?)
Nevertheless, it can be better than that. I believe. That is not the best way to use that excellent driver.
I never tried TM1201 as a direct radiator. I had my horns and wasn't considering it, but now my living space will be very limited and I may get it out of box. Tad TD 4001 which seems to be a natural partner for that mid is not something I would like to listen in close distance on axis. So , is there and smaller cone midrange which could be crossed at 1-1.2Khz up to 8-10kz with efficiency of 100dB and natural tone ?
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