Edgar

In my opinion, based upon the physics of the situation and not based upon any listening tests: at high frequencies, reflectors should be better; at low frequencies it shouldn't matter (though an argument could be made that curling could be better at really low frequencies). As indicated earlier, the definitions of "high" and "low" refer to the relative sizes of the horn and the wavelength, not to any absolute numbers. Greg

Take a look at the images here, and you will see that the answer to your question is, "It depends." As long as the wavelength of the audio is large compared to the dimensions of the folds or bends, then the sound wave is essentially unaffected. But as the frequency is increased, and the wavelength is reduced, bad things begin to happen. At what point are they bad enough to be signifcant? It's a judgment call. Some people say that it's at about 1/2 wavelength. Some say it starts by 1/10 wavelength.

http://groups.google.com/group/rec.antiques.radio+phono/browse_thread/thread/a2f4d23b7f6ec6fc/de5751202590d3d

You are entitled to believe whatever you choose, I guess, but the physics and mathematics of the situation completely contradict your theory. Greg

Lots of possibilities. First, does the hum go away when you connect the amp to a preamp or other source? If so, then just don't ever turn on the amp without it being connected to something. Second, does the amp's line cord have a grounded plug (one with three pins instead of two)? Are you using a "cheater plug" to bypass the ground pin? If you are, then DON'T. Third, get one of those $2 AC circuit testers at Wal Mart and check that your AC plug is wired correctly. Fourth, are there any lamp dimmers in the same AC circuit as the amp? In fact, are there any dimmers in the entire house? If so, remove them, dig a hole in your back yard at least 2' deep, throw them in the hole, cover with dirt, and jump up and down on it until they're packed-in so tightly that they can't escape. Replace with real light switches. If none of these work, then the problem may be in the amp. Could be bad power supply capacitors, cold solder joints, or one of many other things. But check the easy stuff first. Greg

It's really something of an art. I determined the values indicated in that forum thread by putting the designs into my CAD program, then virtually "unfolding" them. Some of the area measurements really have to be judgment calls, because it's difficult to define an area through a fold. Generally S1 is the area just past the motorboard. In Hornresp, the motorboard slot area can be accommodated with the Atc and Vtc parameters. Teaching Hornresp is really a lot more than I'd like to try to handle in forum messages. I believe that there are tutorials on the Web. Greg

Well, the S1-S4 values represent the initial and final areas of the "pieces" (segments). Greg

It's for the Hornresp model. Hornresp only allows four "pieces", so the piecewise model represents the data that I used for those four pieces. Greg

Approximately exponential. It means that the contour is composed of multiple "pieces" that are joined together, rather than in one continuous curve. Greg

Here.

Here's why. Signal manipulation can compensate for only a small fraction of room anomalies. Basically, if you're room is bad, correct the room, not the signal.

I find Search Tempest to be very useful for searching multiple Craigslist locations.

Not. You cannot correct a room by modifying the input to a loudspeaker. You can compensate for some room deficiencies at one fixed listening location, at a cost of making things worse at other listening locations. But to correct a room you have to modify the room itself. Greg

I'm not sure whether you're asking, "Is it okay to use a 'digital' video cable as and 'analog' video cable?", or, "Is it okay to use a video cable as an audio cable?" Either way, the answer is, "Yes." Cables only care about bandwidth. Bandwidth requirements of digital and analog video are roughly comparable ... at least, they're both well within the capabilities of a good RF cable. However, bandwidth requirements for video and audio are considerably different. Some audio interconnects cannot extend high enough in frequency to handle video. I have, on occasion, used a handy audio cable as a video cable, just to see if signal was present. The video was there, but the quality was poor. Very poor. I have purposely avoided the issue of cable impedance. For video it's important, but since you're asking specifically about a video cable, I'm assuming that the impedance is appropriate. For short audio interconnects, it's not nearly so important because the frequencies are so low (wavelengths are so long that the cable is acting much more like a wire than a transmission line). Greg

I have a $10 no-frills phone and a $7/month no-frills plan from Virgin Mobile that I use only for emergencies. I don't give my cell phone number to anybody except family and trusted friends, with instructions that they only use it when all other methods of contact have failed. So far the system works pretty well.

Flaming wall of doo doo.

The funny thing is ... a few hundred Watts through a pair of Klipsch horn-loaded speakers would have provided more volume. Safely.

Line Level Attenuators

There is nothing wrong with your television set. Do not attempt to adjust the picture. We are controlling transmission. If we wish to make it louder, we will bring up the volume. If we wish to make it softer, we will tune it to a whisper. We will control the horizontal. We will control the vertical. We can roll the image, make it flutter. We can change the focus to a soft blur or sharpen it to crystal clarity. For the next hour, sit quietly and we will control all that you see and hear. We repeat: there is nothing wrong with your television set. You are about to participate in a great adventure. You are about to experience the awe and mystery which reaches from the inner mind to... The Outer Limits.

A 'how to' for High Gloss Finishing

There was a product called "Score". Green-colored Vaseline in a toothpaste tube. You put it in your hair ... Greg

Vacu-Form. I still have one. That was in the days before people worried about unsafe toys. Greg

I originally thought that this might be an NTFS/FAT32 problem, see here, but the fact that you can both read and write the external HD from the Mac says that's probably not the case. Still, it might be worth a try. Greg

Absolutely. The meters do not respond as fast as the audio. So with the meters showing 50W, the peaks can be considerably higher than that (especially with the tiny meters on the 8080db). A quick Web search only turned up 8 Ohm ratings. It doesn't look like Sansui ever mentioned 4 Ohm ratings. Some amps are really unhappy with 4 Ohm loads. I'm not saying that it did. I'm just saying that it's one of many possibilities. Cone excursion can become very large in a horn woofer at frequencies below cutoff.

The reason I asked is that what you described seems to indicate that something is being overdriven. Either you're overdriving the amplifiers severely and they're clipping very ungracefully, or they don't like the impedance of the load, or you're bottoming-out the woofers with extremely low frequencies, or something along these lines.