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vur

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About vur

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    Adelaide
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  1. Hi and apology to anyone viewing the video of the AES Duntech presentation.. Another person I sent the file to found it stopped after ~ 25 minutes. I just checked and it is the same for me too. According to my device the file was "modified" i.e. finished at 20:47 which is as I expected and after the presentation ended so I don't know where the rest is. It is 96.8 MB. If you have a clue about this, please let me know. Meanwhile I'll be onto google about it as the device I used was a chromebook.
  2. https://www.dropbox.com/s/5r8wky0gjfhlanc/VID_20190416_204716.mkv?dl=0
  3. The Audio Engineering Society (Adelaide section) tonight. "Loudspeakers and the Time Domain Jack Davis FIEAust, CPEng, AES member St Pauls Creative Centre, (downstairs) Cnr Pulteney & Flinders St Adelaide 7:30pm, Tuesday April 16 th 2019. Join us for a cook's tour of Pulse Coherent Loudspeaker design with Jack Davis, former R&D Manager for Duntech Audio. In this talk Jack will take us through the journey that an aspiring loudspeaker designer would pursue if they wanted to achieve an accurate loudspeaker. The talk starts with the notion of what an accurate loudspeaker might be like and then follows the various problems that would have to be overcome and possible solutions that would have to be devised in the process of developing an accurate loudspeaker. The hypothetical walk through of the design process covers actual problems that arose during the development of the various Classic Series loudspeakers in the late 90's and how they were overcome using the tools and techniques of that time. Jack is currently a Lead Systems Engineer at Raytheon supporting project System Design and Analysis activities. He has held various other positions since his time at Duntech. He graduated from University of Calgary with Bachelor of Science Degrees in Physics and Mechanical Engineering"
  4. I listened thru my Black Knight Dunnies and it sounded better than thru your speakers 😂 I suspect yours were out of phase 😜 Season's Greetings
  5. Good on you. Here's a simple theoretical positioning tip to try if practical for smooth low frequ. response (we KNOW the higher frequencies are "perfect"). Measure your walls and position the speaker fronts at 1/3 or 1/5 or both of those along and in from the walls. Wow that looks like a huge sub in the corner.
  6. ? By cases do you mean the delivery crates for them or do you mean the actual speaker enclosures? Do you plan to build one as a coffin that you can be buried in to pay homage to John Dunlavy?
  7. Re the appearance of the Black Knights and others using the black sox, I have always thought that mirrors up the sides would look cool in some rooms ..... something akin to the Gale 401's with their chrome ends. I happen to have a 2metre x 10cm strip of mirrored acrylic and placing it up the side certainly reduces the look of the sheer bulk but is nbg in my room as I have the BKs either side of a projector screen and reflections ruled the idea out.
  8. Hi frednork. I have two Kenwood L07 monoblocks which connect to the speakers with their specially designed very short leads (30cm). With "high speed amp" design and high damping factor they grab and control the BKs well. They have the supplied Kenwood very long signal leads (10 metre) running to them from a Yamaha home theatre receiver RXV-650. The Kenwoods are virtually satin black and sit inconspicuously on the floor alongside the big Dunnies. I step up on them to dust the piano-black tops of the Dunnies (I jest). For surrounds I have Duntech PCL-3's. Centre speaker is a Kef iQ6C with dual concentric driver and carefully distance/time aligned with the BKs. No subwoofer(s) needed or desired as the BKs would go down to ~20Hz -3deebs by my calculations with the help of the room loading. Unpublished graphs are as .pdfs. BKn fr_resp slow trace.pdfBKn competitor impulses YUK.pdfBKn smoothed fr_resp.pdfBKn phase resp.pdfBKn impulse resp.pdf
  9. I too have a pair of Black Nights / PCL-400's / subsequently called Regent's. They would have been amongst the first 5 pais produced and have massive 450mm thick plinths that stick out 650mm at the front and sides. They are beautifully finished piano black and everyone thinks they are actually polished black stone. Soon after mine were made various different plinths were introduced. I was associated with Duntech and at the factory when they were first presented side by side with a pair of Sovereigns. John Dunlavy's wife (who sewed up the sox by the way) was alongside me and confided that she preferred the BKs, which confirmed what I my ears were telling me too. The BKs sounded more lively whereas the SOVs somewhat strangled or damped. The BKs, with the same 12" woofers, prodigious bass extension, Duntech groundbreaking adherence to accuracy philosophy designed to be a "poor man's Sovereign" at one third the price PLUS I preferred the sound, they were a no-brainer and I ordered mine there and then! Things got better when I had a chance to compare specs because there wasn't a lot of difference overall and indeed the BKs are actually better in some respects. SOVs BKs Efficiency 90 92 fr resp +/-2dB 27Hz-20KHz +2-3dB 28Hz-20KHz9 roll off 12dB/octave below bass res of 27Hz same - below 31Hz phase +/-30deg 50Hz-20KHz +/-20deg 100Hz-15KHz pulse cherency 20us (only) 5us harmnc dis max 1.5% at 30Hz 2% at 35Hz " " <0.3% above 50Hz <0.3% above 60Hz They have been problem free. I rotate the drivers as advised by John. Imaging excellent .... drivers tested & matched (I did a few myself). Apart from all the brochures etc that Dan (the thread originator)has shown us, I am fortunate enough to have unpublished graphs of frequency response smoothed and "rougher", phase response and impulse response. For comparison John supplied impulse response graphs for other so-called excellent speakers of the time Thiel CS5, Snell A/111, Apogee Stage and Hales 2 Signature. The first overshoots and following fades bear no comparison to the BKs. As they are so big and imposing people are expecting bigger bass. Truth is, due to the lack of overhang and low harmonic distortion up into mid bass they sound lean/cool/dry down there. People will comment on how they sound fast and on the transient response. Just sometimes they "chime" and it is hard to explain and I don't understand it myself. It doesn't really sound like the steel rods on the front. They are positioned by the rule of thirds in a 21X20ft room with "cathedral" ceiling and no room nasties all of which which keeps the bass clean. The day is nearing when we will have to downsize but for now we are not letting them go.
  10. On my PC I have 2 Realtek and one AverTV Twinstar tuner. I use DVScheduler V 6 for recordings and edit out adverts or cut off the before and after buffers with VideoReDo V 5. I have used this setup for years with very few problems BUT in the last 3 weeks some recordings are full of audio and/or video errors (as revealed by VRD) and the output files are sometimes shortened to a fraction of the input and useless or unwatchable. SBS is particularly bad, ABC mostly OK and 7,9 & 10 ok and virtually error free. As far as I know I have made no recent changes to my setup and reception on our regular TV and via a set-top-box (to a projector) is fine so I think the antenna setup is OK. The tuner driver versions have not changed. Have SBS & ABC made recent changes making my computer tuners imperfectly compatible?
  11. We tried it with and without the optional amplifier. It missed SBS without the amp but got it with. It tuned all our normal channels that we get with our normal big antenna. It was positioned down near the ground with a car a metre away between it and the broadcaster sender antennas. All channels tuned so it worked better than rabbit ears which we sometimes use with a portable tv which always need a lot of fiddling. Alas we failed to get any extra channels e.g. subscriber ones suggested by the adverts. I would say that if you are having problems with your normal antenna arrangements then this antenna may work better so give it a shot & return if no good. Antennas have always been a mystery to me.
  12. Hi pulinap. Sorry I have to go and you just caught me , but I can't see a message in your reply. Please try again & I'll get back.
  13. Item: Z-TRACK Tonearm/Cartridge damper Location: Adelaide (Highbury 5089) Price: $50 incl. post (I found one advertised for $190) Item Condition: excellent as little used Reason for selling: used with tape-based system and purchased just before migrating to CD's in 1992 Payment Method: cash or Bank Transfer Pickup or post Extra Info:extremely rare in original box with instructions and all parts. This is a tiny piston-with-silicone-damping-fluid shock-absorber (more correctly called a damper) and fairly complicated inside. It is (easily) fitted to the headshell alongside your cartridge where it complements any existing tonearm damping you may have but is better because it works right where you need it rather than back at the tonearm pivot. A teflon skid rides on the surface of the record and the Z-TRACK takes the brunt of warps while keeping your styus mainly reading only the groove and not the warp as well. The skid and stylus are closely aligned with a radius towards the record hole. Resonances from the player, record, headshell and tonearm are damped too. Tracking ability is improved. Unwanted mechanical and acoustical feedback is reduced. Unwanted rumble (which all turntables have)/ subsonic signals are attenuated thus reducing unwanted signal modulation and protecting amplifier and speakers.Pretty much all the stylus has to do is read the groove modulations and produce a purer signal while the damper follows just the record surface. It is very light with 0.5G effective mass. 0.4G increase of tracking force and bias is required. This device is no gimmick. Here's the patent https://www.google.com/patents/US4131284. Once installed, forget. No maintenance required. It makes an unplayable warped record playable. You can hear the improvement on lesser warped records ranging from subtle to obvious. Pictures:
  14. Item: Metrosound stylus balance Calibrated beam with integrated spirit level and sliding weight, spatula and base stand. Location: Adelaide (Highbury 5089) Price: $30 Item Condition:Mint condition with all parts. In holder case and original packaging with instructions. Reason for selling: No longer using vinyl Payment Method: Cash or Bank Transfer pickup or I will post no charge Extra Info: Essential tool for accurate tracking pressure of your cartridge Pictures:
  15. I TOO FOUND IT VERY INTERESTING although much is beyond me, but I did expand my knowledge. Thanks very much. If you are not already familiar with DV Scheduler sydney.edu.au/engineering/it/~efax/DV%20Scheduler.html ‎ from the gist of your project I think you may be interested.
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