Negative dbs

[mtrycrafts]

Dynamic range has nothing to do with the lower pre-amp signal of DVD players. That's just the way they are designed. If your rail voltage is +/- 60V then any signal you send in will clip after it reaches 60V. If the output level is 1.4V p-p on a DVD player it just takes more volume level to clip it than if it was a 2V p-p signal. So the level displayed on the receiver correlates with the input signal strength and doesn't have anything to do with the inadequacies of the receiver.

The quote you are responding to is from AV-phile. He is confused with the issues.

 

[Leprkon]

not to be obnoxious, but....

shouldn't a receiver measure output in watts, rather than in dB ? dB come from the size, efficiency, and placement of the speakers. without some kind of tuning device, the receiver has no clue exactly how much sound pressure (dB) it produces from a give rise in electrical power (watts)

 

[Votrax]

shouldn't a receiver measure output in watts, rather than in dB ? dB come from the size, efficiency, and placement of the speakers. without some kind of tuning device, the receiver has no clue exactly how much sound pressure (dB) it produces from a give rise in electrical power (watts)

Good question. The decibal unit is a logarithmic unit of measurement for sound level, voltage gain, and power gain.

 

[mtrycrafts]

shouldn't a receiver measure output in watts, rather than in dB ?

Watts can be referenced to dB power and is referenced to 1 watt power. So, amps can be referenced either way.



dB come from the size, efficiency, and placement of the speakers.

That is a different measurement, dB spl at certain distances with certain power input.

the receiver has no clue exactly how much sound pressure (dB) it produces from a give rise in electrical power (watts)

Yes, you are correct if you are referring to dB SPL at an identified distance, etc. Amps are also rated in dB power above 1 watts. 20dB power, re 1 watt is a 100 watt amp.

 

[annunaki]

Mtrycrafts is quite correct here.

 

[Leprkon]

more obnoxiousness

so to answer the leading question in the thread, the receiver companies show minus dB (decibals) which become less negative as the dB (decibels, which are already positive) increase, until the dB (decibals) reach a reference point, at which point the dB (decibals) stop being negative and become positive, which is approximately the same point that the dB (decibels) begin to cause permanent hearing damage (depending, of course, on the size, efficiency, and placement of the speakers)

no wonder no one was ever able to catch up with Mr Cooper (DB).....or was it Sweeney.. I guess I keep getting my DB's confused....