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Anyone ever try placing a delay on the stereo information in a sound system. I'm not saying put a delay on either the left or right channel only; this might help one side of the car, but it will hurt the other. Anyone ever try Left channel minus Right channel, Delay, then Add back into Left channel plus Right channel. Just wondering if this might push out the stage on both sides of the car (passenger and driver).
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Posts: 76 | From: Quispamsis, New Brunswick, Canada | Registered: Oct 1999
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I've been thinking of a variation on this. I've done this with my home stereo and it works pretty well. Hook up the rear speakers to the same amp that is running your front speakers, but instead of hooking the neg. leads to the amp, hook the left neg. and the right neg. together. The difference between left and right (the stereo info.) goes to the back. To attenuate the signal, put an L-pad in series. It's the basis of Dolby surround, the difference between left and right go to back and addition of left and right go to centre channel. It makes certain music come to life. On others with little seperation, it does little. It's interesting to play with, and a very cheap surround for your old home system! As far as the delay goes, that's something else I've been meaning to try (to make my reg. cab pickup sound bigger) for a long time, just never got around to it. Combining the two sounds very interesting. I was thinking that I'd use a decent set of midrange drivers so as not to make the bass sloppy or take away from the soundstage in the front. Oops, I just found a post that was written in sound quality by audiophyle that says the same damn thing. ------------------ inno73@hotmail.com
[This message has been edited by Inno (edited 10-10-99).]
Posts: 490 | From: Fort Frances, Ontario, Canada | Registered: May 1999
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posted
I have a Sherwood home amp that does the EXACT thing you suggested. You're right about how it makes the sound come to life. I've also run that type of setup in my car, the same way you've suggested; not quite as dramatic, but it sure gets ya thinkin. I'd really like to try my idea and see how it works but I don't have access to an audio delay (mucho $$$$).
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Posts: 76 | From: Quispamsis, New Brunswick, Canada | Registered: Oct 1999
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I read an article from a car audio mag. (don't remember which one) from the late 80s and they did a review on a guitar effects pedal that did just a delay. It cost about $80 and apparently worked pretty well. Only trouble with that is I'm sure guitar effects are pretty low quality and it could end up sounding terrible. Probably not shielded enough for car use either. You'd only need one channel for that type of setup so that's a bonus. Another cheap way is to put an inductor in parallel with the speaker (I think). I don't know what value would give what time delay (maybe I'll dig out a textbook), but it may work. Actually don't try it 'till I do a little more research, at least not with any equipment that's of great value to you.........:-)
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[This message has been edited by Inno (edited 10-12-99).]
Posts: 490 | From: Fort Frances, Ontario, Canada | Registered: May 1999
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posted
An inductor can cause a small delay, but only at a small range of frequencies. Inductors and capacitors cannot be used to generate a constant delay over the entire audio spectrum. I was thinking more along the lines of a digital delay system that uses a microprocessor or fancy buffer. Anyone know of any companies that sell them (CHEAP).
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Posts: 76 | From: Quispamsis, New Brunswick, Canada | Registered: Oct 1999
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The audio mag that ran the article on the delay guitar pebal was Car Stereo Review. I think he used a Boss Roland pedal or something like that. I thought about trying that.
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I don't know of any cheap ones (depending on your definition of "cheap"). I wonder what type of ICs they use for some of the digital ones. I'll pull something apart when I get back to work and see what I can find. You may be able to build one.
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Posts: 490 | From: Fort Frances, Ontario, Canada | Registered: May 1999
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I have had a course on microprocessors and how to set them up and stuff. I've been considering trying to design a digital delay system for quite some time now. I keep running into some logic problems in the program itself though. I've found that the number of commands in the program is critical. With a 2MHz (Motorola 6800) microprocessor, you're pretty well limited to 40 clock cycles in the loop( 50KHz samples). Most commands require like 3 or 4 cycles. So now you're only talking like 10 commands. This makes the design VERY difficult. Well, with the microprocessor that I'm familiar with at least. For anyone who has any experience in this field, here is the main problem: I can create a program that can generate the delay. Each sample is placed in a consecutively greater location in memory. The output is taken from a specifically lower location. The problem is that the input from the ADC will eventually overwrite the program. Anyone know of a way to keep the program running but not interfere with RAM?
Sorry if this makes little sense, but it's been a long day.
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Posts: 76 | From: Quispamsis, New Brunswick, Canada | Registered: Oct 1999
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posted
Umm.. This is probably silly, but how about using two mp's and making your program switch from one output to another after a given number of cycles... And refresh the other mp on the off cycles?
ShadowStar
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Computers are a lot like air conditioners.. Open Windows and they become useless..
The day Microsoft makes something that doesn't suck is the day they make vacuums.
Posts: 2578 | From: Somewhere In the Northeast | Registered: May 1999
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As it is, I already have to use two mp's, one for the lower 8 bits of the sample and one for the upper 8 bits of the sample. The 6800 uses 8 bit accumulators. I was thinking of trying to use the stack but I will have to read up on it. It's been about a year since i've done anything with microprocessors. Your idea of switching from one to another is interesting but I think the only way it will wok is if the program can get into an infinite loop with as little code as possible. Your suggestion would probably take up too much microprocessor time.
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Posts: 76 | From: Quispamsis, New Brunswick, Canada | Registered: Oct 1999
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