Trooper

Justin, Logic 7 is, essentially, Lexicon/Harman's version of Pro-Logic II - they work in the same fashion. It actually preceded Pro-Logic II. L7 can take a 2 channel signal and make up to 7 channels from it. In many of the Harman Kardon receivers they use a version that only makes 5 channels since that's all the receiver can handle. DD EX and THX EX can make a 5.1 soundtrack into 7.1. Maybe Lexicon is also using L7 processing to make the 2 extra channels.

I found a good way to get some air movement and keep the fan quiet. Get a fan with a diameter of around 4 inches or so and a voltage rating of 24 volts DC. Now hook the fan up to a 12 volt (or so) DC supply. The motor will now turn a little slower and make much less noise but because of the size of the fan still move enough air to keep things cool.

The power rating of a driver is not typically the point at which it starts to compress. All drivers compress sooner or later. For many drivers out there the the power rating number is what they can survive. They may have long since stopped increasing their output an the rate you would think. Actually, if the KHorn is within 2.6dB of the ideal you calculated at 100W I would say that's pretty good. What do you think Tom?

Higher bit rates, such as 75kbps, just means more information/less data compression. DTS is a higher bit rate because it uses less compression (vs. DD). CDs are limited to a theoretical 22.05kHz and standard DD/DTS DVDs are limited to 24kHz. Audio resolution is is the numer of bits (16, 24, etc.) This basically dictates the dynamic range and signal to noise ratio capability as well as the "preciseness" of each sample to the original analog signal. More bits = better. I'm not that familiar with the bit rate displayed by the DVD player so I can't quickly speak to it's relationship to the sample rate although it would seem they would be directly related whereas a doubling of the sample rate should double the bit rate. The DACs are at the mercy of whatever signal they receive when it comes to sample rate. They will default to whatever is coming from the player. A higher number of bits (16,18,24) is not related to sample rate/sampling speed. It is related to bit rate (75kbps). So the difference you hear between DTS @ 75kbps and DD @ 45kbps has nothing to do with sample rate (which is always 48kHz) and everything to do with the bit rate which is higher because DTS uses less compression. A video DVD (not including a 24bit/96khz type) will not produce anything over 24kHz whether it's standard pcm (actually 22.05khz), DTS or DD. Even if you play a 24/96 disc your player may well output it at 48kHz. With this you would get the benefit of more bits (resolution) but not the higher sampling rate (HF extension).

Whoa there! Looks like major confusion in the bits and sampling rate arena. cc1091, I think you mean 4, 8 and 24 times oversampling (sometimes just written as "24x oversampling"). Oversampling is a way to move the digital noise and artifacts far out of the audio band. CDs have a sampling rate of 44.1kHz and early players required a steep analog filter to filter out the noise above 20kHz. This caused it's own sonic problems. By oversampling and moving the noise further out of the audible band the output filters become much simpler and have much less effect on the audio. Make any sense? Now on to bits. CDs are 16 bit. Using Digital-to-analog converters with higher bit capability results in higher performance and lower noise output. Most D/A integrated circuits (ICs) have actually become 1-bit converters with performance equal to or better than 20 or 24 bit converters. A few years ago someone demonstrated to me the audible difference between a "real" 18-bit converter and a 1-bit converter (with 18-bit performance). 1-bit converters have much better low level linearity. This is both measurable and audible (very audible with the right test tones). Sampling rates must be at least 2x the highest frequency you want to reproduce. Theoretically a CD recorded at 44.1kHz can reproduce sound up to 22.05kHz. I believe DD and DTS are both sampled at 48kHz (not to be confused with their bit rates Boa12). The sampling rate is based on Nyquist's theorem regarding aliasing/anti-aliasing. Pretty complicated topics, hope this helps (or at least doesn't hurt).