Table Mountain...
http://www.precision-devices.com/file-downloads/PD1850DataSheet110912.pdf
In my experience the PD1850 is the single best bass driver I have heard.
I believe running two or 4 (!) of these in a open baffle "table" design would be a thing of sonic beauty and also useful for testing the buildings structural limits...!
I dont have the space at home to run them open baffle in VPL frames, (best of both U & H frames with none of the disadvantages / limitations, see some of my other posts), and its hard to disguise the 100 cubic feet of air they need in sealed boxes.
Please resist the temptation to go for the ported option, sealed always sounds better to my ears. Some gentle Eq / DSP will also be worth it.
http://www.precision-devices.com/file-downloads/PD1850DataSheet110912.pdf
In my experience the PD1850 is the single best bass driver I have heard.
I believe running two or 4 (!) of these in a open baffle "table" design would be a thing of sonic beauty and also useful for testing the buildings structural limits...!
I dont have the space at home to run them open baffle in VPL frames, (best of both U & H frames with none of the disadvantages / limitations, see some of my other posts), and its hard to disguise the 100 cubic feet of air they need in sealed boxes.
Please resist the temptation to go for the ported option, sealed always sounds better to my ears. Some gentle Eq / DSP will also be worth it.
Car Speakers are in abundance in The States. Unfortunately, Car Speakers will not fit the criteria. They need to be pro audio (sound reinforcement) speakers.
They are 4 ohm nominal single coil or dual coil 2 ohms nominal woofers. Pro Audio 18 inch woofers are 8 ohms nominal. I could use twice the amount of 18 inch drivers and achieve the proper SPL while moving to those drivers would be making a step backwards in performance. This is why guys in sound reinforcement industry don't use car speakers.
I am currently using twenty four 18 inch Beymas and looking to upgrade my drivers offering a QTS 0.37 to a QTS of 0.5 or higher.
Thise IB drivers are all single coill (4Ohm) drivers, there are no dual VC versions from Fi, and I dont recall ever seeing a dual VC IB driver. Like I say, this isnt a driver intended for vehicle use (those it does get used this way by some people), its intended for in home use. I'm not sure why you feel the driver isnt what you would be looking for, and why your focusing on pro audio drivers that will likely not match the IB for sound quality or go anything like as deep.
IMHO, a system with a Q of .3 wont sound very good at all, its far to low. A .5 Q is better but still a little low for home theater use. Ive not read the whole thread though so maybe I'm missing something?
IMHO, a system with a Q of .3 wont sound very good at all, its far to low. A .5 Q is better but still a little low for home theater use. Ive not read the whole thread though so maybe I'm missing something?
I am into sound reinforcement not home audio. So the woofers I am seeking need to be aimed for the sound reinforcement market not for the home or car audio.
As I mentioned in my previous post, I am currently using twenty-four, 18 inch Beyma woofers. The QTS of each driver is 0.37 and I am looking to upgrade to drivers offering a QTS of 0.5 or higher. The free air resonance of the driver needs to be 30 Hz or lower, and the impedance must have a nominal load of 8 ohms.
I already own 18-inch woofers that offer a QTS of 0.55 with an fs of 30 Hz so I know exactly what to expect under the given conditions. These drivers are no longer in production (I purchased them 10 years ago) and I only have four in which I need twenty-four.
So I am basically looking for 18-inch drivers aimed for the sound reinforcement market with a QTS of 0.5 (or greater) a free air resonance of 30 Hz (or lower) and a nominal impedance load of 8 ohms.
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You might consider adding a small resistor, EV did this on drivers that had too low of a Qts.
Strassacker: Speaker Building, Components
It would only take about 0.39Ω to raise the Qts to 0.5 on the Eminence Kilomax Pro 18A (current version). The resistance of the speaker wire and connectors would raise this even further.
Some of the power amplifiers in the older Yamaha receivers actually had a 0.22Ω resistor in series with the speaker out. Carver had a Sunfire model with a ~1Ω resistor that fed different binding posts that were marked 'tube sound' (or some such). Some Mark Levinson amplifiers had a switch to change the output impedance of the amplifier via the feedback loop (which you probably don't want to do).
Some people at the Klipsch forum got carried away with reducing the DCR of the crossover inductors and found out that the bass got too lean sounding, there was a reason the woofer inductor had a DCR of 0.5Ω, Klipsch was not just trying to save money.
Strassacker: Speaker Building, Components
It would only take about 0.39Ω to raise the Qts to 0.5 on the Eminence Kilomax Pro 18A (current version). The resistance of the speaker wire and connectors would raise this even further.
Some of the power amplifiers in the older Yamaha receivers actually had a 0.22Ω resistor in series with the speaker out. Carver had a Sunfire model with a ~1Ω resistor that fed different binding posts that were marked 'tube sound' (or some such). Some Mark Levinson amplifiers had a switch to change the output impedance of the amplifier via the feedback loop (which you probably don't want to do).
Some people at the Klipsch forum got carried away with reducing the DCR of the crossover inductors and found out that the bass got too lean sounding, there was a reason the woofer inductor had a DCR of 0.5Ω, Klipsch was not just trying to save money.
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sounds more like a downgrade
sorry, poor joke
do you really use dipole for PA speakers
Fane Sovereign have those specs
but the new Beyma 18LX60V2 might be better built
I'm still not following exactly what your intended use would be, 'sound reinforcement' isnt that specific. If your looking for drivers to go into cabinets, those IB's probably wont do as they would need huge cabinets, but 24 would get you well over 130db at 20hz. What sort of cabinet do you intend to use.
sounds more like a downgrade
sorry, poor joke
do you really use dipole for PA speakers
Fane Sovereign have those specs
but the new Beyma 18LX60V2 might be better built
I own twelve Double Eighteens (twenty-four Beyma 18 G 550s) reflex bins operating on six Crown MA 5000vz. My inquiry is not aimed towards home audio so dipoles are not the agenda.
I had my eyes focused on the Beyma 18 LX 60v2 ever since Beyma brought the LX series back to the market. I own a few of the older 18 LX 60 so I know what they are capable of doing. However I wanted to keep my options open which is why I asked if anyone knows of an 18-inch driver offering a QTS of 0.5 (or greater) sporting an fs of 30 Hz (or lower) with an 8 ohm nominal load.
Once I have a few to choose from, I can begin to process and eliminate the weak ones based on high mechanical losses.
Because an 18-inch driver with a QTS of 0.5 or greater with an fs of 30 Hz can maintain its output gain as you move further down the frequencies without the aid of equalisation to make up the loss when compared to an 18-inch driver with a QTS of 0.3 offering an fs of 30 Hz.
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If you mean free air, yes. I focus primarily on 18-inch drivers so I have no idea where drivers smaller than a 15-inch stands.
http://s56.beta.photobucket.com/use...lProvsPeaveyandEminence.gif.html?sort=3&o=121
Shows the highest Qts driver with the lowest efficiency having the most output.
Shows the highest Qts driver with the lowest efficiency having the most output.
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