I was quite impressed with RCF bass drivers. Did you post a pic of a compressor and expect me to guess what driver it is?
I guess, I did 
It's the 950 2.0.
There's also a 1.4" version, which was tested by Vance Dickason.
It seems the 2.0 is preferred by PA folks who have tested both.
RCF woofers are very nice indeed and not too expensive either.
In Europe their sub drivers are popular for diy tapped horns.
It's the 950 2.0.
There's also a 1.4" version, which was tested by Vance Dickason.
It seems the 2.0 is preferred by PA folks who have tested both.
RCF woofers are very nice indeed and not too expensive either.
In Europe their sub drivers are popular for diy tapped horns.
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Titanium must be an improvement over Aluminum but lesser than Beryllium.
I guess radian aint all that? And no one seems to be partial to the BMS 4590 at all....
I've been able to consecutively convince myself to stick to a compression driver vs a ribbon planar. Peoples impression along with my own, over paper specs, I'm certainly confused, judging by spectral decay, horns would not be the accurate one, but CD's are not letting on to this supposed exaggeration of color, somehow.
I guess radian aint all that? And no one seems to be partial to the BMS 4590 at all....
I've been able to consecutively convince myself to stick to a compression driver vs a ribbon planar. Peoples impression along with my own, over paper specs, I'm certainly confused, judging by spectral decay, horns would not be the accurate one, but CD's are not letting on to this supposed exaggeration of color, somehow.
Radian is right up there with the best. My experience as well as others have been very positive.
The Radian diaphragm is an alloy with aluminum, titanium, and copper if I recall correctly.
Once equalized, most drivers sound very similar. Maximum clean output is the main difference. Advantage is for larger diaphragms.
Let's look at the available options from maximum clean displacement.
1. BMS 4594HE is the current best option for wide bandwidth high output designs. Downsides is it's a two way design that works best actively crossed. Need to know your stuff when it comes to crossovers.
2. Various Beryllium equipped 4" 1.4/1.5" exit compression drivers.
3. 4" diaphragms with flexible surrounds.
4. 4" diaphragms with one piece titanium dome/surround.
Upcoming options:
1. Celestion Axi2050. Long wait time for this one. Could be years.
2. B&C coaxial. DCX464. Available later this year.
The Radian diaphragm is an alloy with aluminum, titanium, and copper if I recall correctly.
Once equalized, most drivers sound very similar. Maximum clean output is the main difference. Advantage is for larger diaphragms.
Let's look at the available options from maximum clean displacement.
1. BMS 4594HE is the current best option for wide bandwidth high output designs. Downsides is it's a two way design that works best actively crossed. Need to know your stuff when it comes to crossovers.
2. Various Beryllium equipped 4" 1.4/1.5" exit compression drivers.
3. 4" diaphragms with flexible surrounds.
4. 4" diaphragms with one piece titanium dome/surround.
Upcoming options:
1. Celestion Axi2050. Long wait time for this one. Could be years.
2. B&C coaxial. DCX464. Available later this year.
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BE Al then ti
Ti is popular with the pros because it does not work harden when you slap the diaphragm onto the phase plug, this means you can abuse it and not have it harden and then shatter. Ti has a lower physical structural resonance around 8KHz which drives some folks crazy fortunately not a lot of people though. Aluminum is a superior diaphragm material with a higher frequency break up mode and Be is even lighter and stiffer again pushing up the first break up mode. Aluminum is probably the very best all around diaphragm material for performance Vs cost. Some of the modern plastic diaphragms are good for lower level (home) use with lower compression ratio driver designs.
Ti is popular with the pros because it does not work harden when you slap the diaphragm onto the phase plug, this means you can abuse it and not have it harden and then shatter. Ti has a lower physical structural resonance around 8KHz which drives some folks crazy fortunately not a lot of people though. Aluminum is a superior diaphragm material with a higher frequency break up mode and Be is even lighter and stiffer again pushing up the first break up mode. Aluminum is probably the very best all around diaphragm material for performance Vs cost. Some of the modern plastic diaphragms are good for lower level (home) use with lower compression ratio driver designs.
In general, aluminum and titanium perform about the same from the standpoint of 10-20 kHz chatter. Poly ring diaphragms can perform better--close to beryllium domes.
My experience with the BMS 4592ND is that it just needs EQing. The figure below for the midrange diaphragm output channels of 4592ND on a K-402 horn. There are three more input PEQs for the crossover interference bands:
Chris
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Thank you so much for your post ErnieM! I really appreciate you organizing the tactic, it’s all new to me, so I needed the oversight.
So for a waveguide I don’t see much going outside of the Goldwood GM-450PB 2"
I found a selenium 90x40 made of fiberglass but some complaints of quality control on demensions and I didn’t figure out of it had a diffraction slot, which I understand to undesirable. Do you have any insight to a solution?
K-402 horns are not for sale btw
So for a waveguide I don’t see much going outside of the Goldwood GM-450PB 2"
I found a selenium 90x40 made of fiberglass but some complaints of quality control on demensions and I didn’t figure out of it had a diffraction slot, which I understand to undesirable. Do you have any insight to a solution?
K-402 horns are not for sale btw
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The seos waveguides are the easiest large waveguides to get a hold of. 24", 30", or 36" model.
Lots of success with these at the AVS forums. One guy is running Beryllium Radian 950pb's on a seos 24 down to 600hz for large format studio monitor use.
18 Sound makes well designed horns good for 800hz. XT1464 is quite popular.
For woofers. AE is the best you can easily buy. BMS woofers are very close as well and are being used in many home audio projects.
With all that said....you might also consider kits from Diysoundgroup like the "Maximus 12" or Troels "The Loudspeaker".
Lots of success with these at the AVS forums. One guy is running Beryllium Radian 950pb's on a seos 24 down to 600hz for large format studio monitor use.
18 Sound makes well designed horns good for 800hz. XT1464 is quite popular.
For woofers. AE is the best you can easily buy. BMS woofers are very close as well and are being used in many home audio projects.
With all that said....you might also consider kits from Diysoundgroup like the "Maximus 12" or Troels "The Loudspeaker".
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The only Radian I've heard is the 475PB, which I own. Sounds sweet and detailed to me.
If budget is unrestricted, the number of options increases considerably.
The Radian drivers are quite expensive over here, so they face lots of competition from European manufacturers.
Moreover, in the past Radian was known for reliability issues.
Modern R&D brought forth improvements in motor structure, phase plugs and diaphragms. Due to economies of scale, bigger companies are able to offer these products to competitive prices.
The Radian drivers are quite expensive over here, so they face lots of competition from European manufacturers.
Moreover, in the past Radian was known for reliability issues.
Modern R&D brought forth improvements in motor structure, phase plugs and diaphragms. Due to economies of scale, bigger companies are able to offer these products to competitive prices.
Sort of, sort of not. He did mention coaxes so a Unity/Synergy does fit that bill...
I think you may have just tipped my decision over to that. The design I have needs CNC so there is that expense. The Shows need a pair of EVM12L, which I think I have stored in my shed. Mine will also be corner mounted, but I will want an octave more extension than Bruce mentions as I have a lot of electronic music that I know goes down there.
The hardest part is going to be transferring the original design to 18mm metric timber.
It took my peanut brain a moment to remember what they are, so I will be interested to see what you do with them.
And to you my friend.
In this thread Bjørn (Omholt) shares his experiments with the K402 + Celestion Axi2050 and Radian 950PB.
Despite the advanced R&D involved, the Axi2050 seems on par with the 950PB. It goes lower, but doesn't perform as well in the top octave.
Despite the advanced R&D involved, the Axi2050 seems on par with the 950PB. It goes lower, but doesn't perform as well in the top octave.
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OK, Thanks again
I actually have been set on AE 15 until I decided, maybe, I could get away with using an 18". Their 18" didn't play low enough or too big a box require...something..I'll recheck them out.
For an 18" I'm really digging the SAF184.01
http://www.lavocespeakers.com/lavoc...87263_LAVOCE_SAF184.01_18in_SUBWOOFER_A.a.pdf
Should be able to cross at 700hz. The size keeps the excursion lower than would be with a smaller woofer.
950PB vs 951? The 950 seems to have a smoother response curve. It cost more but has a smaller exit....I thought the 2" exit was more desirable? Sure are a lot more horns for 1.4"
edit: DOES SOMEONE KNOW WHERE/HOW TO ACTUALLY ACQUIRE A K-402!!! XD
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Hi Brett,
Ha, ha, mine are fairly modified also. Looking form the side there is a smooth curve from the top of the horn throughout the mouth, and expanding form has been used to damp vibrations. Although Bruce really liks the EVM12L as well as EVM15L for his horns, I believe that mine has D130 or D131 AlNiCo.
I am not sure how will you achieve extra octave of extension, I listen mostly to classical so 40 Hz was fine.
Let me know what you end up with.
I respectfully disagree with the "peanut brain", first based on your posts, second the drivers are not exactly a commodity. I had them in conical horn with last 1/3 of the length having M'Cleah mouth calculated for 250Hz, about 25 inch diameter. My friend is putting this together for now: https://ucarecdn.audiogon.com/05385...scale_crop/840x630/center/-/quality/lightest/, but I am thinking something along Chris' (Cask05) MEH.
Kindest regards,
M
Ha, ha, mine are fairly modified also. Looking form the side there is a smooth curve from the top of the horn throughout the mouth, and expanding form has been used to damp vibrations. Although Bruce really liks the EVM12L as well as EVM15L for his horns, I believe that mine has D130 or D131 AlNiCo.
I am not sure how will you achieve extra octave of extension, I listen mostly to classical so 40 Hz was fine.
Let me know what you end up with.
I respectfully disagree with the "peanut brain", first based on your posts, second the drivers are not exactly a commodity. I had them in conical horn with last 1/3 of the length having M'Cleah mouth calculated for 250Hz, about 25 inch diameter. My friend is putting this together for now: https://ucarecdn.audiogon.com/05385...scale_crop/840x630/center/-/quality/lightest/, but I am thinking something along Chris' (Cask05) MEH.
Kindest regards,
M
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This is probably the most comprehensive thread on synergies.
In the following old comment by Tom Danley (about the SH-50), the synergy concept is briefly and concisely summarized:
"The speaker is very different, its shape and design driven entirely by the acoustics and overall goals.
The design was driven by the desire to fix the “self interference” that multiple sound sources produce when they are spaced more than about ¼ wl apart. You know, just like when a woofer is less than ¼ wl apart from a second woofer, they add coherently, same is true all the way up..
If multiway hifi speaker’s radiation were ever measured in the spherical domain (where does the sound actually go), one would find that at crossover in particular, the two ranges interfere and produce lobes going every which way.
In particular, multi-way horn systems generally suffer even more from “self interference” than direct radiators, as the sources tend to be larger and farther apart at crossover.
Contrary to what one might think, these acoustic problems in location in the H and V planes cannot be “fixed” with DSP.
The approach I used for combining all the ranges within the horn follows the following approach.
A horn (or its acoustic gain is among other things) is like a high pass filter based on the rate of expansion in area.
What one see’s with a simple conical horn is that the expansion rate is very rapid at the apex, a very rapid expansion equals a high frequency horns. As you move away from the apex, the expansion rate slows, making for a lower frequency horn.
If one taps into the side of a conical horn, one finds the lower limit is still set by the local expansion rate while a limit at the upper end exists as you approach the frequency where the reflected wave from the closed end returns out of phase (1/4 wl distance).
The idea is to divide a single horn flare up into its logical sections, driven by a driver suitable for that frequency range and with all the drivers being less than ¼ wl apart in there arrange of operation, they combine coherently into one source.
You notice the drivers are separated front to back as well with the tweeter being farthest to the rear. This separation off sets the phase shift and intrinsic delays of each range so that the system will reproduce a square wave from about 220Hz to 2600Hz (traversing all three frequency ranges).
One last detail, all drivers produce distortion at multiples of the input frequency.
Here, each of the cone drivers passes the sound through an acoustic low pass filter which is made from the trapped front volume and holes that couple into the horn.
That acoustic low pass corner is just above the electrical crossover and has the effect of not passing distortion components, which are above crossover.
The bottom line is that they have time response similar to a Manger but have orders of magnitude less harmonic distortion and go orders of magnitude louder, go down to 50Hz and have constant directivity.
While not meant for the living room, they were developed there and I could never go back."
In the following old comment by Tom Danley (about the SH-50), the synergy concept is briefly and concisely summarized:
"The speaker is very different, its shape and design driven entirely by the acoustics and overall goals.
The design was driven by the desire to fix the “self interference” that multiple sound sources produce when they are spaced more than about ¼ wl apart. You know, just like when a woofer is less than ¼ wl apart from a second woofer, they add coherently, same is true all the way up..
If multiway hifi speaker’s radiation were ever measured in the spherical domain (where does the sound actually go), one would find that at crossover in particular, the two ranges interfere and produce lobes going every which way.
In particular, multi-way horn systems generally suffer even more from “self interference” than direct radiators, as the sources tend to be larger and farther apart at crossover.
Contrary to what one might think, these acoustic problems in location in the H and V planes cannot be “fixed” with DSP.
The approach I used for combining all the ranges within the horn follows the following approach.
A horn (or its acoustic gain is among other things) is like a high pass filter based on the rate of expansion in area.
What one see’s with a simple conical horn is that the expansion rate is very rapid at the apex, a very rapid expansion equals a high frequency horns. As you move away from the apex, the expansion rate slows, making for a lower frequency horn.
If one taps into the side of a conical horn, one finds the lower limit is still set by the local expansion rate while a limit at the upper end exists as you approach the frequency where the reflected wave from the closed end returns out of phase (1/4 wl distance).
The idea is to divide a single horn flare up into its logical sections, driven by a driver suitable for that frequency range and with all the drivers being less than ¼ wl apart in there arrange of operation, they combine coherently into one source.
You notice the drivers are separated front to back as well with the tweeter being farthest to the rear. This separation off sets the phase shift and intrinsic delays of each range so that the system will reproduce a square wave from about 220Hz to 2600Hz (traversing all three frequency ranges).
One last detail, all drivers produce distortion at multiples of the input frequency.
Here, each of the cone drivers passes the sound through an acoustic low pass filter which is made from the trapped front volume and holes that couple into the horn.
That acoustic low pass corner is just above the electrical crossover and has the effect of not passing distortion components, which are above crossover.
The bottom line is that they have time response similar to a Manger but have orders of magnitude less harmonic distortion and go orders of magnitude louder, go down to 50Hz and have constant directivity.
While not meant for the living room, they were developed there and I could never go back."
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