Does -71 dB noise matter in a car?
Between driver THD, panel resonances, a 60dB background noise floor and 85dB safe hearing limit? Unlikely.
Does -71 dB noise matter in a car?
But typical listening conditions is not generally how we judge amp noise. At home or on the desk we judge the noise by running the amp chain at typical gain with silent input signal, moving your ears close to the speaker and if there's no hiss then it's ok. I don't see why similar shouldn't apply in a car. A lot of people have cars that are objects of pride and very comfortable, luxurious even. So why wouldn't it be reasonable to sit in it and listen? A lot of cars, even those with an ICE, are quiet when it is idling and a lot turn off the ICE when the car is stopped. And in cars the tweeters are sometimes within 1 meter of the ears in the normal listening configuration, without moving your ears close to them.What is the typical background noise level in a moving car? You are NEVER going to hear the noise component in a 69 dB SINAD from a car amplifier!
The noise level in a car depends on the speed and also on engine speed, wind, tires and ground conditions.I wonder what the noise-level is in a car. I guess very good performance are wasted in a car compared to ones living room. Does an amp for a car have to be better than this?
Ask the House of Windsor.Forced perspective can have a tendency to play tricks on one's perceptions. Do you really believe that that guy's hands are as big as his head?
When you're parked in the woods.Does -71 dB noise matter in a car?
And that noise is dynamic, varying with speed, road surface, weather, etc. This is why I am a bit puzzled by concerns about THD, S/N, etc. in car stereos. If peaks are (dangerously) at 100dB, and background noise is at, say, 70dB, you have only 30dB of audible range to work with. That's about 3% THD. Isn't everything below that going to be inaudible?It is surprisingly high: most cars at 70 mph read between low 60 to 75 dB, not counting the noise from the traffic around you
I was going to post up the Specs but you beat me to it. Thank you Sir for your incredible support and assistance.This thing is huge! Amazing value for the price.
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Specs.>
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You can't use single number SPL numbers to determine audibility. You have to have its spectrum. Directional noise from a tweeter will be more audible than diffused noise. And speaker noise multiplies with number of speakers you have.And that noise is dynamic, varying with speed, road surface, weather, etc. This is why I am a bit puzzled by concerns about THD, S/N, etc. in car stereos. If peaks are (dangerously) at 100dB, and background noise is at, say, 70dB, you have only 30dB of audible range to work with. That's about 3% THD. Isn't everything below that going to be inaudible?
*Have you given up posting the comparison bar-graph? (the Alpine review had it)So many years went by since I bought my Alpine PDX-V9 and things have not evolved much I see. Except for price. But still.
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Alpine PDX-V9 Review (car amplifier)
This is a review and detailed measurements of the Alpine PDX-V9 four channel amplifier plus subwoofer amp. It is on kind loan from a member and costs US $999. Despite having one more channel than PDX-F6, The V9 is in the same box: Let's see if it measures as well as the F6 did. Alpine PDX-V9...audiosciencereview.com
The factory power rating is 400 W RMS /ch @ 4 Ohms stereo output. (With the voltage delivered @ clipping = ~ 56.6 V peak @ ~ 14.1 A peak.)Fun review. I don’t spend much time critically listening to music in my car any more. And the whole market has changed since I was a kid. It used to be a thing to install an Alpine deck in your car. Now everything is so packaged up by what the manufacturer offers it’s hard to imagine cutting apart your dashboard for good sound. My guess is this amp is more than capable of delivering Zeppelins Kashmir at ear splitting levels in your old El Camino. With road noise probably completely transparent. Might want to ask your girlfriend first though.![]()
No, a car is one of the worst acoustic environments possible. All that reflecting glass and you can never really sit centrally in the right spot. I gave up on car audio years ago, news/weather is about all it's good for.I wonder what the noise-level is in a car. I guess very good performance are wasted in a car compared to ones living room. Does an amp for a car have to be better than this?
Oh, had forgotten that I made a category for it.*Have you given up posting the comparison bar-graph? (the Alpine review had it)
Weather? Roll those windows down and rock out friend.No, a car is one of the worst acoustic environments possible. All that reflecting glass and you can never really sit centrally in the right spot. I gave up on car audio years ago, news/weather is about all it's good for.
You can and some do this. The car only outputs 12-14volts so that can be an issue as any car(or other type of amp) amp needs to draw very high amperage to make high power in 12volt systems, not all amps can do this.Why not just battery power some of the inexpensive but good measuring amps like Fosi if you want great sound? Of course in a car...
Yes. I also believe sun hangs few hundred meters above the cloudsForced perspective can have a tendency to play tricks on one's perceptions. Do you really believe that that guy's hands are as big as his head?