Arkytype

Might want to look at Litz-type cables. Their construction tends to negate the skin-effect endemic to conventional solid conductors. Lee

Klipsch forum member Greg Roberts (best known for his V-trac horn and Klipsch restoration projects) should be proud. The September 2013 issue of Stereophile features his beautifully executed Vittora loudspeakers. Art Dudley's Listening column has nothing but praise for the Vittora's all horn-loaded design. The review is not on the www.voltiaudio website yet, but you can get a look at the gorgeous models Greg has built. Here's a link to an interview from June, 2012 which gives us insight into Greg's design process. http://dagogo.com/an-interview-with-greg-roberts-of-volti-audio Lee

Wonder if anyone will hear a difference in the sound of their audio system as a result? Maybe, but you'll need to reverse the polarity of all your loudspeaker drivers when the solar event completes its pole reversal. Lee

About 20 years ago I tried to clean the front panel a Denon receiver I picked up cheap at a yard sale. Note I said "tried". I used either Simple Green or Formula 409 (can't remember which) and sprayed the front panel, waited a minute and proceeded to wipe off all the dirt and grime. What I wasn't counting on was that I also wiped off all the lettering!! :>( Lee

I've found that setting my center Belle 6 dB lower (using SPL meter at listening position) than the combined output of my two flanking Klipschorns is just about right. If you have a helper, try sitting at the sweet spot and while listening to a well-recorded vocal (e.g. James Taylor), have helper raise the volume of the center Belle until it is just noticeable. Shift your listening position left and right of center and note that the vocal image seems to stay more centered than with the center Belle off. You will probably discover that raising the center Belle level to match each of the flanking loudspeakers (i.e. 85 dBL 85 dBC 85 dBR) is too much center fill. Lee

Ron, Audiophiles don't use cooling fans---they use Rotary Gas Acceleration Devices! Lee

There's not much I can add to Gil's cogent argument. I had forgotten PWK's piston in a lake example. One of the key benefits to horn loading a driver is higher acoustic output compared to simply mounting the driver on a baffle. The other benefit is lower distortion. PWK wrote extensively about modulation distortion and re-reading those papers are well worth the time. The less the diaphragm has to move, the lower distortion it will generate. In one of the Dope From Hope (ca. 1971?), Paul wrote that the Klipschorn could generate a 32 Hz note at one acoustic watt output with a woofer diaphragm motion of 1/16" peak-to-peak! One acoustic watt is the equivalent of a sound pressure level of 120 dB. For the Klipschorn, Belle and La Scala, that would require only 40 watts input power! djk's response was both uncivil and cornfusing. How does posting the data for a 10" woofer help with arash's valid question? While I've not used the Horn Response software, I noted a glaring error in the data window labeled "Sample". A sound pressure level of 133.3065 dB does not translate to an acoustic output power of 129.8809 watts; it corresponds to an acoustic power level of 21.42 watts. To be more precise, acoustic power is expressed in watts per square meter. The best web site I've found for understanding the relationship between acoustic and electrical measurement and properties is http://www.sengpielaudio.com Lee

Dr. Frederick Frankenstein: Perhaps I can help you with that hump. Igor: What hump? Lee

Can ya say comb filter? I knew ya could! With apologies to Fred Rogers. Lee

JL, I had a"dead" IBM HD several years ago. Removed it from its rails and held it my hand horizontally oriented. Upon powerup gave it a good CC (or CCW?) flip of the wrist. The HD came up to speed and the PC booted normally. Got a second HD and xferred important files from old one. If you can afford it, a SSHD is the way to go. Have a new Dell laptop with one and I swear Windows 7 boots up in 10 seconds or less! Lee

Moray, There are perhaps a half dozen names for what is commonly called a "constant directivity" horn. Dozens of patents have been awarded to individuals who have purported to improve on the "prior art" surrounding loudspeaker horn directivity design. While I don't normally use Wikipedia as a source of technical info, the link offers a quick and dirty overview and history of horn design. See if you can spot the error in the horn animation. http://en.wikipedia.org/wiki/Horn_loudspeaker Charlie Hughes' patent is well worth reading as he describes other past designs. http://www.google.com/patents/US6059069?dq=6059069&hl=en&sa=X&ei=Og_JUJXmJIrJqQHpx4CoBA&ved=0CDQQ6AEwAA A true constant directivity horn requires special EQ. This Peavey Tech Note gives a good description of CD horns. http://www.peavey.com/support/technotes/soundsystems/horn_eq.cfm Currently the so-called tractrix horns have found favor among audiophiles and Klipsch even got the word "tractrix" copyrighted! If you do any research or reading, you'll quickly learn there is no one design goal that all designers will agree on that would create the "perfect horn". Controlling dispersion/directivity is an elusive goal but one worth pursuing. I think Dave's Eliptrac 400 would be (to my ears) hard to improve on. Lee

For a source of low-cost wall treatment, try these. They come in black, burgundy & tan. The fabric is fire-rated. http://www.samsclub.com/sams/acoustic-panels-24-x-40-4-pk-black/193623.ip?sprodId=193623#spec http://www.unitedplastics.com/consumer-my-theater.php Lee

Dirk, Interesting project. I really like the concept of the MiniDSP! According to one of the MiniDSP forums, depending upon the plug-in loaded and filters enabled, the unit can have a latency of up to 2.5 msec. I just happened to have finished the tedious task of measuring the acoustical path length thru one of my Klipschorns. The mean path length from the woofer side of the throat to the front edge (mouth) is.....wait for it.... 68 inches. That translates to a path delay of 5.014 msec. Add those two delays together and you get 7.5 msec. Of course, there will be some delay involved getting the woofer to moved after voltage is applied. Anyone got a different path measurement for their Klipschorn? Regards, Lee

Coytee--- artto is correct-----your home's electrical system should only be earth grounded at one point which is usually designated as the service entrance. Keep in mind the grounding conductor and the neutral are connected together at this one point. The distribution box you are adding should not be grounded to a separate earth ground--just connect the ground bus to your primary service entrance's grouning bus. For more positive electrical connection to your equipment's power plugs, wire your addition with 20-amp receptacles.If you plan to use 20-amp breakers, you will have to use #12 (or larger) wiring. It's OK to use a 15-amp breaker on a 20-amp receptacle, but the inverse violates NEC. Running an isolated grounding wire from the receptacle(s) you plan to use for audio is a good start to help prevent unwelcome hum. If you have the budget, I highly recommend using a balanced power distribution system. There are rack-mounted products out there as well as DIY articles on line. I am using a 1.5 kW-rated Signal Transformer in a balanced configuration to power my audio rack. Hum is inaudible at any volume setting. Lee

Here's a link to the original article posted on the www.synaudcon.com website. The boundry labels are correct--Pat Brown knows his stuff. Thee are quite a few technical papers available on a free non-member basis. http://www.synaudcon.com/site/wp-content/uploads/2012/03/VOL36_DEC08_Boundaries-1.pdf Lee

We installed a Rinnai propane unit when we built our home five years ago. It is in the laundry room above the washer & dryer and central to all hot water runs. It has performed flawlessly. However, while you can have "endless hot water", be sure when you turn on the hot water tap that the water flow is enough to trigger the unit into operation. Otherwise, you'll get a cold slug of water when you least expect it! To determine which model to choose, be sure to check the flow curves on the web site. The colder your incoming water is, the lower the hot water flow rate will be. In the winter, our incoming water temperature runs about 55-60 degrees and with the 7.5 gal/minute model, we have plenty of hot water. Lee

Matteo, To quote PWK, "Miniaturized bass speakers have been attempted, but so far no one has invented a miniature 32-foot wavelength." Lee

Hello Dee, I use Neutrik connectors for all my home/pro gear. The NF2C-B/2 phono connectors are nice because they connect the signal ground before the hot when plugging in and disconnect the hot before the ground when unplugging--just the opposite of the conventional RCA connector. Sure saves speaker cones if you are a "hot patcher" like me! The connector comes with two sizes of strain reliefs and can handle cable up to 0.29" diameter. A strain relief for fat cables is also available. As for cable, I use Clark Wire & Cable RS22G2. It's easy to strip and comes in a dual-pair configuration in multiple color combinations. I'm not sure what the minimum order is but I usually order 100' which lasts me several years. http://www.clarkwire.com/cableRS22G2.htm Lee

The first image is at the labs at Indy and the second is at the lab in Hope. Note the 1/4" microphone and cable on one of the Hope PW tubes. If memory serves me correctly, the PW tubes at Hope are filled with tapered open cell foam. The far end of the tubes are connected to a sealed box probably filled with foam. Lee