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#101278 - 25/06/2002 09:32 cooledit tone generator
image
old hand

Registered: 28/04/2002
Posts: 770
Loc: Los Angeles, CA
i'm preparing to install my new front separates, so i decided to generate a 1khz test tone at 0db to determine clipping, etc. tried to play it in my car right now.. seems really loud. louder than any of my normalized music.

so i ask (tony specifically, since i know he did this already), this test tone from colledit pro isnt inheritly clipping at the source, right?

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#101279 - 25/06/2002 10:56 Re: cooledit tone generator [Re: image]
image
old hand

Registered: 28/04/2002
Posts: 770
Loc: Los Angeles, CA
well, i decided to play the tone on my system at 0db. i successfully blew my stock front mids. had the burning smell and everything. probably not the tone's fault. just that i didnt start off w/ min gain on my amp. well, live and learn. at least i'm getting new ones today. heh. so not a real loss. didint think that my stocks could handle the 50w that the amp was driving with anyways.

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#101280 - 25/06/2002 11:35 Re: cooledit tone generator [Re: image]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31563
Loc: Seattle, WA
so i ask (tony specifically, since i know he did this already), this test tone from colledit pro isnt inheritly clipping at the source, right?

Correct.

However, pure test tones always sound louder than music. They deflect the waveform to its maximum amount, 100 percent of the time, constantly. Regular music only does a maximum deflection on occasional rare peaks.

Just view a piece of music in CoolEdit compared to a test tone in CoolEdit and you can literally SEE the difference.

That's why you always turn down the volume before playing a test tone and gradually increase it until it's loud enough to do your tests with (but never up all the way). Also, I would never have used a test tone to measure distortion/clipping. I'd only use music for that. Very dangerous, for the reasons stated above.

Sorry to hear about the blown speakers. Live and learn, eh?
_________________________
Tony Fabris

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#101281 - 25/06/2002 13:09 Re: cooledit tone generator [Re: tfabris]
image
old hand

Registered: 28/04/2002
Posts: 770
Loc: Los Angeles, CA
well, i was wondering then what db the tones are in test cds (ie. Autosound 2000), because i want to generate them instead of buying the damn cd. i saw a post about an old test cd, but theres no were to download it (hint, hint =).

thinking about getting an oscilloscope to do find the max gain possible for my new components, so i'm gonna need this.

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#101282 - 25/06/2002 13:16 Re: cooledit tone generator [Re: image]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31563
Loc: Seattle, WA
well, i was wondering then what db the tones are in test cds (ie. Autosound 2000), because i want to generate them instead of buying the damn cd.

I'd guess they're probably not 100 percent deflection, but somewhere below that. It's possible to generate a less-than-100-percent wave in CoolEdit if you want. Not sure how the AutoSound CD handles it, because I'm sure the CD comes with instructions on how to use the individual tones (something that you won't get if you pirate it off the web).

Another thing to consider: If you download an MP3 version of one of the tracks on the autosound CD, it won't be exactly the same because of HF rolloff and compression artifacts. If you wanted to use those tracks, I would only consider it useful if it was a raw WAV rip straight from the original CD.
_________________________
Tony Fabris

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