Hi Everybody
I recently bought a pair of the wonderful Radian 950pb 2" compression driver - and it's simply stunning. My JBL 2435HPL is nothing compared to the Radian.
However, I'm not quite pleased with the serious beaming of my 400 Hz tractrix horns.
The dispersion doesn't match my midrange speaker very good, either.
Therefore: I could really use some help picking up the best possible horn for my Radians, which isn't extremely huge. I would prefer a width less than 16 inches.
I use TAD TL-1601a for lows and TAD TM-1201H for the mids.
Appreciate any suggestions.
Thanks,
Jeppe
I recently bought a pair of the wonderful Radian 950pb 2" compression driver - and it's simply stunning. My JBL 2435HPL is nothing compared to the Radian.
However, I'm not quite pleased with the serious beaming of my 400 Hz tractrix horns.
The dispersion doesn't match my midrange speaker very good, either.
Therefore: I could really use some help picking up the best possible horn for my Radians, which isn't extremely huge. I would prefer a width less than 16 inches.
I use TAD TL-1601a for lows and TAD TM-1201H for the mids.
Appreciate any suggestions.
Thanks,
Jeppe
What is the crossover frequency you are hoping for? 16" seems pretty small... especially for a driver capable of being crossed over at a fairly low in frequency.
If space wasn't a concern I would go for something like this:
E-JMLC-300
there are quite a few nice horns for sale on that web page though... might be worth browsing around...
If space wasn't a concern I would go for something like this:
E-JMLC-300
there are quite a few nice horns for sale on that web page though... might be worth browsing around...
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This horn would probably be perfect for your needs:
Behringer electric - Behringer electric Horn
This is a H9800 clone (JBL S9800) fitted for the 1.4" exit of the 950PB (with the 1.4"/2" adapter removed, ie "951PB"). This is a biradial horn with good directivity behavior up to the UHF (thanks to the 1.4" exit), and good horizontal control down to ~800Hz
Behringer electric - Behringer electric Horn
This is a H9800 clone (JBL S9800) fitted for the 1.4" exit of the 950PB (with the 1.4"/2" adapter removed, ie "951PB"). This is a biradial horn with good directivity behavior up to the UHF (thanks to the 1.4" exit), and good horizontal control down to ~800Hz
Jeppe - Why not keep your 400 Hz tractrix and integrate a tweeter where it starts to beam (8000 Hz?) rather than replace the horn? I ended up adding an upper midrange (650 Hz JMLC) to my 300 Hz tractrix in addition to a tweeter.
I'm curious how you're running your TAD 1201s...I have a pair that I'm looking to try out either in a large horn or a sealed box.
I'm curious how you're running your TAD 1201s...I have a pair that I'm looking to try out either in a large horn or a sealed box.
pos: I think this sounds quite invasive, but I'll try emailing him. Thanks!
green heron: Because the tractrixs dispersion is a mismatch are the frequecy where I like to XO. And 400 Hz tractrix is quite big - mine is in carbon fiber and stack birch plywood.
Quite nice looking, but just too big. I'm not using the radial horn any more.
The 1201s are fantastic in a sealed enclosure. Way better than the Radians up to about 1kHz.
Have thought of replacing the Radian with the Beyma TPL-150H, but real life measurements seems to differ a bit from spec'd by Beyma. Haven't heard it either.
Rgs,
Jeppe
green heron: Because the tractrixs dispersion is a mismatch are the frequecy where I like to XO. And 400 Hz tractrix is quite big - mine is in carbon fiber and stack birch plywood.
An externally hosted image should be here but it was not working when we last tested it.
Quite nice looking, but just too big. I'm not using the radial horn any more.
The 1201s are fantastic in a sealed enclosure. Way better than the Radians up to about 1kHz.
Have thought of replacing the Radian with the Beyma TPL-150H, but real life measurements seems to differ a bit from spec'd by Beyma. Haven't heard it either.
Rgs,
Jeppe
While a nice horn (also from Autotech), it's a fair bit larger than requested.
It also extends lower than necessary for his application and doesn't have quite the dispersion pattern he is looking for (..I *think*, but could be wrong).
General Note: the radial mentioned by pos is a diffraction design.
virious,
You have some of the best reviewed high efficiency drivers. For a 3-way design with a cone midbass some of the best reviewed designs pay attention to:
1) Controlled Directivity. Using the TAD TM-1201H for the midrange will provide clean, dynamic sound to 1.2-1.4Khz where it starts to produce a 90 degree polar response. (early beaming from a large cone). Crossing to a 1" tweeter horn like the 90x40 SEOS_15 will provide a smooth polar response and even power response through the Xover range. A 90x40 degree tweeter horn pattern is frequently recommended for multi-seat home audio/theater. A 60x40 degree tweeter horn pattern is a common recommendation for small rooms. The Radian 475PB is a well reviewed 1" CD option. A 1" CD that avoids break-up to 18K-20K would be normal recommendation.
2) Lobing (horn honk). The main recommendation is to butt the SEOS tweeter waveguide as close as possible to the TAD TM-1201H to minimize C-to-C. Lambda/4 C-to-C spacing at the Xover is the ideal. Lambda/2 the largest acceptable.
3) Edge diffraction. A large radius around the cabinet edges is proven to improve imaging. A 3" and 4" quater round is the dream .... 1.5" router bits are cheap DIY.
4) Physical time alignment of drivers. Sometimes the horn depth is customized. Sometimes a sexy tilt to the front baffle does the job.
5) Crossovers require prayer.
You have some of the best reviewed high efficiency drivers. For a 3-way design with a cone midbass some of the best reviewed designs pay attention to:
1) Controlled Directivity. Using the TAD TM-1201H for the midrange will provide clean, dynamic sound to 1.2-1.4Khz where it starts to produce a 90 degree polar response. (early beaming from a large cone). Crossing to a 1" tweeter horn like the 90x40 SEOS_15 will provide a smooth polar response and even power response through the Xover range. A 90x40 degree tweeter horn pattern is frequently recommended for multi-seat home audio/theater. A 60x40 degree tweeter horn pattern is a common recommendation for small rooms. The Radian 475PB is a well reviewed 1" CD option. A 1" CD that avoids break-up to 18K-20K would be normal recommendation.
2) Lobing (horn honk). The main recommendation is to butt the SEOS tweeter waveguide as close as possible to the TAD TM-1201H to minimize C-to-C. Lambda/4 C-to-C spacing at the Xover is the ideal. Lambda/2 the largest acceptable.
3) Edge diffraction. A large radius around the cabinet edges is proven to improve imaging. A 3" and 4" quater round is the dream .... 1.5" router bits are cheap DIY.
4) Physical time alignment of drivers. Sometimes the horn depth is customized. Sometimes a sexy tilt to the front baffle does the job.
5) Crossovers require prayer.
Attachments
I agree. However, the Radians is just a very nice sounding driver and I haven't listened to many 1" - the TAD TD-2001 is quite nice, though. And is also very expensive.
Thanks,
Jeppe
You're absolutely right! I might try the Radian 475PB as it's not that expensive here in Europe. But the TD-2001 from TAD is nice as well.
The boxes in the picture is just for testing. I have arranged that a very knowledged engineer will help me getting the most out of these lovely units.
Did you listen to the 1" Radian compared to it's bigger brother?
Actually I listen to the 950pb without any horn at the moment as the tractrix drives me nuts.
Really appreciate your comments
Rgs,
Jeppe
My setuyp is quite similar to yours:
TL1801 + TM1201H + JBL 2450SL/H9800 (with truextent Be diaphram)
I find compression drivers with 4" diaphragms (1.5" or 2") really superior to 1.75" diaphragmed ones (1"), even when crossed over above 1khz.
Going from your 950PB to a 475PB or even a TD2001 would probably be a downgrade, especially if you find the 950PB better than the 2435HPL (3" diaphragm).
There are two problems with large diaphragm compression drivers though:
- the larger exit (especially 2") dictates a higher directivity in the UHF
- breakups modes start at lower frequencies and the UHF suffers
Ths first problem (directivity) has two solutions: using a horn that incorporate special devices to improve direcitvity (fins like the TH4001/A290, or diffraction slot like the 2360A) at the cost of some "bluring" (HOM, etc.), or use a driver with a 1.4" or 1.5" exit and no throat (and a *good* phasing plug, which is the case for the 950PB, but not for the 2435HPL...) which will maintain an acceptable directivity up high.
The second problem (breakups) is more difficult to handle. JBL usually ressorts to aquaplas coating to absorb breakups in his high end offering, and that works quite well at a minor cost. The other solution is to use beryllium, with Truextent diaphragm (~$500 a pop), which will also give you ~3dB of bonus efficiency in the midband (but the UHF will still require a lot of EQ).
Of course another solution for both problems is to use a tweeter
Are you using an active crossover?
TL1801 + TM1201H + JBL 2450SL/H9800 (with truextent Be diaphram)
I find compression drivers with 4" diaphragms (1.5" or 2") really superior to 1.75" diaphragmed ones (1"), even when crossed over above 1khz.
Going from your 950PB to a 475PB or even a TD2001 would probably be a downgrade, especially if you find the 950PB better than the 2435HPL (3" diaphragm).
There are two problems with large diaphragm compression drivers though:
- the larger exit (especially 2") dictates a higher directivity in the UHF
- breakups modes start at lower frequencies and the UHF suffers
Ths first problem (directivity) has two solutions: using a horn that incorporate special devices to improve direcitvity (fins like the TH4001/A290, or diffraction slot like the 2360A) at the cost of some "bluring" (HOM, etc.), or use a driver with a 1.4" or 1.5" exit and no throat (and a *good* phasing plug, which is the case for the 950PB, but not for the 2435HPL...) which will maintain an acceptable directivity up high.
The second problem (breakups) is more difficult to handle. JBL usually ressorts to aquaplas coating to absorb breakups in his high end offering, and that works quite well at a minor cost. The other solution is to use beryllium, with Truextent diaphragm (~$500 a pop), which will also give you ~3dB of bonus efficiency in the midband (but the UHF will still require a lot of EQ).
Of course another solution for both problems is to use a tweeter
Are you using an active crossover?
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Very nice setup, pos. Do you have any pictures of it?
I would have no problem adding a tweeter to avoid break-up modes and directivity issues.
The JBL 2435HPL is definitely not up to par with the Radian, and since it got these Radians very cheap I would like to keep them.
I have only heard the Yuichi A290 (actually a pair made by Yuichi himself) mated to a cheap Selenium driver and it was very very good indeed. Only problem is the size of this horn
Yup - I use a DriveRack PA+ digital croosover.
Any suggestion to a horn besides the Behringer Electric horn?
Thanks,
Jeppe
I would have no problem adding a tweeter to avoid break-up modes and directivity issues.
The JBL 2435HPL is definitely not up to par with the Radian, and since it got these Radians very cheap I would like to keep them.
I have only heard the Yuichi A290 (actually a pair made by Yuichi himself) mated to a cheap Selenium driver and it was very very good indeed. Only problem is the size of this horn
Yup - I use a DriveRack PA+ digital croosover.
Any suggestion to a horn besides the Behringer Electric horn?
Thanks,
Jeppe
No picture, my system is ugly
As for another horn suggestion, if you are going to use a tweeter and keep the Radian in its 2" state you can try the "new" square tractrix horns from stereo lab:
Tractrix Horns Vintage Series - STEREO LAB
Given the dimensions it might be less beamy than their round offering...
If you can convert your Radian into a 1.5" driver (I think everything is possible: 2"/1.5"/1.4") with the proper bolt pattern, then you can also try the JBL PT waveguides, which come in different dimensions (square or rectangulat, 12" large) and directivities (60*40, 90*50, 100*100) and are usable down to ~1200Hz.
As for another horn suggestion, if you are going to use a tweeter and keep the Radian in its 2" state you can try the "new" square tractrix horns from stereo lab:
Tractrix Horns Vintage Series - STEREO LAB
Given the dimensions it might be less beamy than their round offering...
If you can convert your Radian into a 1.5" driver (I think everything is possible: 2"/1.5"/1.4") with the proper bolt pattern, then you can also try the JBL PT waveguides, which come in different dimensions (square or rectangulat, 12" large) and directivities (60*40, 90*50, 100*100) and are usable down to ~1200Hz.
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