When John Dunlavy owned Duntech in Adelaide it was based at Technology Park in a facility provided by the South Australian government to entice John to come to Adelaide to work as a RF specialist for the defence industry, or at least that was John's story. There was no acoustic anechoic chamber in that facility, however there was an RF anechoic chamber for antenna development which looks similar and would likely have been casually mistaken to be for acoustics. I suspect John would have happily let people keep this false assumption as he was a bit of a salesman. As far as I understand he used a dual channel FFT to measure step response for driver quality assurance, not anechoic measurements. This is because his loudspeaker systems were designed to recreate an acoustic waveform at the design distance of 10' that has the same shape in the time domain as the electrical waveform input to the speaker. To do this requires a lot more technically acuity than conventional loudspeaker design and came from his understanding of broadband RF antennae wave recontruction. In the mid-late 1980s John Dunlavy was gratious enough to allow me to use his test facilities at the Technology Park factory to develop loudspeakers manufactured for in-house use at the Adelaide Festival Centre where I was the Technical Manager for Sound at the time. I had the cabinets made by Krix at Hackham, who also wound inductors for Duntech's crossovers.
When John Dunlavy departed Adelaide with debts due to his subcontractors, the loudspeaker part of his business was disposed through an insolvency liquidator. From this time forward (1998) his designs continued to be made under the Dunlevy brand without any input or control from John himself.
In the early 2000s I was employed by Vaf Research and one role was to develop the manufacturing quality assurance manual for the production of the Signature i93 and i66 models. I believe that before Vaf Research was founded, or at least before it was a serious entity and not just a hobby, the owner was in a partnership with Andrew Cole to make cabinets for some Duntech models (I don't recall the name of that business partnership). When I last heard, Andrew Cole was still involved in loudspeaker cabinet manufacturing for a number of small speaker manufacturers in Adelaide. John Dunlavy used an number of cabinet makers around Adelaide, including a kitchen joinery business called Alby Turner and Sons based near Modbury who made the Sovereign enclosures. The design objectives and design approach for the Vaf Signature series share little with John Dunlavy's loudspeakers; in fact the time domain performance of the Seas drivers used in the Signatures are entirely unsuitable for Duntech's designs and John would have instantly rejected them for anything with his name on it.
When John Dunlavy departed Adelaide with debts due to his subcontractors, the loudspeaker part of his business was disposed through an insolvency liquidator. From this time forward (1998) his designs continued to be made under the Dunlevy brand without any input or control from John himself.
In the early 2000s I was employed by Vaf Research and one role was to develop the manufacturing quality assurance manual for the production of the Signature i93 and i66 models. I believe that before Vaf Research was founded, or at least before it was a serious entity and not just a hobby, the owner was in a partnership with Andrew Cole to make cabinets for some Duntech models (I don't recall the name of that business partnership). When I last heard, Andrew Cole was still involved in loudspeaker cabinet manufacturing for a number of small speaker manufacturers in Adelaide. John Dunlavy used an number of cabinet makers around Adelaide, including a kitchen joinery business called Alby Turner and Sons based near Modbury who made the Sovereign enclosures. The design objectives and design approach for the Vaf Signature series share little with John Dunlavy's loudspeakers; in fact the time domain performance of the Seas drivers used in the Signatures are entirely unsuitable for Duntech's designs and John would have instantly rejected them for anything with his name on it.
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All,
I have been considering a large design maybe Duntech Sovereign or Dunlavy SC VI with either 12" or 15" woofers.
I have built many systems and my last real big build was a reflex-based system so my next big build will be sealed box lowish Q
I have been searching for suitable drivers for some time and am currently looking at the SB Acoustics range of 12"- and 15-inch drivers. SB 15" Review
The SB results in a F3 of 36 Hz (–6 dB = 28.2 Hz) with a QTC = 0.7 for the 4.75-ft3 closed box, which is where I want to be. The system using two of these will be large.
The high performance ScanSpeak 13" Woofer here is also of interest.
I have a multitude of other drivers from 8" downwards, so the rest of the range will be covered. Strong demountable baffles initially will allow me to play with various options as well as outboard crossovers..
Driving them will not be an issue with larger Krell power amps, Orelle XTC Pow One and Naim 250/135s in residence.
Early days.
One thing I know is that I will end up with a beast up to and around 78" tall up to 17" wide and 36" deep overall.
My spouse is fine with that and she thinks my Spendor SA3 and Yamaha NS1000 speakers are quite small!! My last big build was based upon the Wilson X1.
I will read the rest of this thread and go from there.
Simon
I have been considering a large design maybe Duntech Sovereign or Dunlavy SC VI with either 12" or 15" woofers.
I have built many systems and my last real big build was a reflex-based system so my next big build will be sealed box lowish Q
I have been searching for suitable drivers for some time and am currently looking at the SB Acoustics range of 12"- and 15-inch drivers. SB 15" Review
The SB results in a F3 of 36 Hz (–6 dB = 28.2 Hz) with a QTC = 0.7 for the 4.75-ft3 closed box, which is where I want to be. The system using two of these will be large.
The high performance ScanSpeak 13" Woofer here is also of interest.
I have a multitude of other drivers from 8" downwards, so the rest of the range will be covered. Strong demountable baffles initially will allow me to play with various options as well as outboard crossovers..
Driving them will not be an issue with larger Krell power amps, Orelle XTC Pow One and Naim 250/135s in residence.
Early days.
One thing I know is that I will end up with a beast up to and around 78" tall up to 17" wide and 36" deep overall.
My spouse is fine with that and she thinks my Spendor SA3 and Yamaha NS1000 speakers are quite small!! My last big build was based upon the Wilson X1.
I will read the rest of this thread and go from there.
Simon
Yup... it's wild. I went with a friend of mine - last in August - to visit him, and I can assure you.... it's an experience for sure. The stereo image is spot on and everything is super clear, where it all just works! Great voices and enormous weight to the soundYeah... take a look at this one, all DIY, the subs are 8 driver 24" subs in what I think is 2400 liter total cabinet volume, for midbass there is 6 15" drivers .... pretty way over the top
Heard some classical music with cannons.... and simply put - protect your ears .... but still sounded great.
He liked a bit more bass than I normally prefer. But he had several filters ready, which when changed, quickly made me give him a thumbs up
The system had that sweet clean hifi stereo image, that I like. Going for horns, to play this loud, is for me a bit too "in your face". I simply prefer the higher coverage of sound - wider dispersion. Compression or loaded drivers surely has a great and effective coupling to the air, but to me, it becomes somehow too much. So this system is definitely some of the best I have heard
The first system I've ever heard, where a FIR based filter was used, and I did not think about it in any way
Also, rather impressed with the way that the 4x Morel midranges and Bliesma tweeter integrated
The Duntech Sovereign PCL-2001 used the Dynaudio 30W100 I believe? Not sure if there is a modern equivalent?