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sayitnelly
06-05-2018, 01:50 PM
Guys I'm trying to get some good speakers but I keep running into something known as signal to noise ratio? What exactly does that mean? I know it's an obvious math formula but how does it work?

Sorry I'm not that technically smart but I've been getting involved with music production lately as well so I think learning about it will only help.

Thx and sorry if it's considered a 'dumb' question.

Bruce Watson
06-05-2018, 05:30 PM
Guys I'm trying to get some good speakers but I keep running into something known as signal to noise ratio? What exactly does that mean?

Signal to noise ratio (https://en.wikipedia.org/wiki/Signal-to-noise_ratio) is simply a measure of the relationship between the signal (be that music, voice, whatever you're interested in) and the noise (be that the rumble of a passing truck, the hiss that an amplifier makes when the gain is really cranked up, or anything that you are *not* interested in).

Consider the case of a singer at an outdoor cafe. When you are a long way away, you can see the cafe and the singer, but the noise of the traffic around you prevents you from hearing much of the song, and you can't interpret the words. The loudness level of the traffic noise might be higher than the loudness level of the singer; the singer is lost in the noise.

As you walk closer to the cafe, the sound of the singer's voice gets louder while the traffic noise stays the same (same traffic on the same street). This makes it easier to hear the singer and at some point you'll be close enough to understand the words to the song. This happens when the loudness level of the singer is sufficiently higher than the loudness level of the traffic noise. Once you reach the cafe and take a seat the singer is sufficiently louder than the noise that you have little trouble hearing the singer. This is a higher signal to noise ratio.

Really, that's mostly what signal to noise ratio is about -- how easy is it for you to hear the singer?

davef
06-05-2018, 06:12 PM
Guys I'm trying to get some good speakers but I keep running into something known as signal to noise ratio? What exactly does that mean? I know it's an obvious math formula but how does it work?

Sorry I'm not that technically smart but I've been getting involved with music production lately as well so I think learning about it will only help.

Thx and sorry if it's considered a 'dumb' question.

Bruce provided a pretty good answer. S/N Ratio doesn't apply to passive loudspeakers. Technically speaking, S/N Ratio really only applies to the noise and signal generated by the same device. Passive loudspeakers don't generate "noise", thus it isn't an appropriate specification for a loudspeaker. If it is listed as a spec for a loudspeaker, it is simply marketing hyperbole and I would stay far away from this particular loudspeaker.

in Audio, SNR is a specification for amplifiers, pre-amplifiers, CD players, cassette decks (what are those ;) ) etc... Electronic devices etc. It is the ratio between the background noise the device generates (noise floor) and the signal itself. A low ratio means the device generates quite a bit of background noise. 70dB and higher is typically considered pretty good for analog devices, while digital components should be at least 100dB... It is also not a representation of sound quality.

Unless you are looking at powered speakers, it is a specification that does not apply to loudspeakers as passive speakers do not generate background noise. Since a number can not be divided by zero (signal level divided by noise level), the spec is meaningless in this application.