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#205697 - 19/02/2004 12:45 Smooth Volume Adjust
Diznario
enthusiast

Registered: 17/10/2001
Posts: 265
Loc: Portland OR
I'm sure this has been discussed before, but I had another incident this weekend, so I thought I'd mention it...

How about adding a little smoothing or slowing algorithm to the volume adjustment?

I've noticed that alot of people who ride in my car seem to have trouble adjusting the volume on the empeg. Often times they turn the knob a little too fast, or maybe the empeg just doesn't react as fast as they would like, and they keep spinning it.

Invariably, what ends up happening is that they turn up the volume way higher than they meant too. This wouldn't normally be a big deal, but with the burly aftermarket sound systems some of us have in our cars, wooooo, it can get a little sketchy.

What I really want is for it to never instantly increase the volume. Make it nice and smooth. Kinda like the volume ramp up at start, but effective at all times.

I don't mind being able to rapidly decrease the volume, but rapidly increasing is almost never a good thing.

I guess this kinda goes along with the "Fade in from a pause" request.
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Dario
MK2 in an Impreza 2.5RS

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#205698 - 19/02/2004 12:51 Re: Smooth Volume Adjust [Re: Diznario]
wfaulk
carpal tunnel

Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
This raises the question of why you've installed a sound system that can go so much louder than you want.
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Bitt Faulk

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#205699 - 19/02/2004 14:04 Re: Smooth Volume Adjust [Re: Diznario]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31594
Loc: Seattle, WA
I would also like to see a speed limit on volume increases, but no speed limit on volume decreases.

Note that the source of the problem is a combination of old encoders, debouncing problems, and CPU/disk timing issues.

The rotary encoder is actually interpreted as switches where each click is an up or a down. If the encoder is old/dirty, then it seems like more clicks are happening than there really are. Okay, that's problem one.

Debouncing is the code name for a software algorithm that tries to tell the difference between a dirty signal and a deliberate on/off/on sequence of switch presses. Sometimes the debounce logic isn't aggressive enough, especially as the switches age. That's problem two.

The third and final problem starts at the place the software tries to decide if you want a fast knob spin or a slow one. It says, "Okay, over the last X milliseconds, I've seen Y number of volume-up clicks." Then, depending on the ratio of X to Y, it increases the volume by Z amount.

But for some reason, if the player's CPU/disk is loaded down during that calculation, it doesn't seem to "get" all of the "clicks" over the longer time period. It seems like the clicks only hit the algorithm at the end, after the CPU/disk processing is done. So what the algorithm sees is all the clicks coming at once instead of seeing them appear spaced out over time. So Z in the calculation above is really big and it blasts you to death.

I think it would be cool if they could try and address the 2nd and 3rd problem somewhere during 3.0 alpha/beta...
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Tony Fabris

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#205700 - 19/02/2004 16:13 Re: Smooth Volume Adjust [Re: tfabris]
loren
carpal tunnel

Registered: 23/08/2000
Posts: 3826
Loc: SLC, UT, USA
Agreed. This is still driving me batty evan after installing a new rotary encoder. It just never seems to have the same correlation of rotations/clicks to volume increase/decrease. It's always hit or miss.

As for colume ramp up... that STILL doesn't work for me, never has. It is quite for a half second then instantly jumps to full volume. This is on V2 final.
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#205701 - 19/02/2004 16:17 Re: Smooth Volume Adjust [Re: tfabris]
brendanhoar
enthusiast

Registered: 09/06/2003
Posts: 297
> Debouncing is the code name for a software algorithm that
> tries to tell the difference between a dirty signal and a
> deliberate on/off/on sequence of switch presses.
> Sometimes the debounce logic isn't aggressive enough,
> especially as the switches age.

That's twice this week that I've seen key debouncing come up (a friend is working on low-level stuff for one of the *BSDs).

Somewhere, in the back of my head, is the elementary school memory of having to load a special program every time I used the TRS-80 Model Is (or was it IIIs?) to cure an annoying keyboard key bounce issue.

-brendan

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#205702 - 19/02/2004 17:38 Re: Smooth Volume Adjust [Re: brendanhoar]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31594
Loc: Seattle, WA
I remembered the first time I saw the key debounce code in the ROM of the Commodore 64. I was like, "you mean they have to waste software memory for this crap? Why isn't that taken care of in the electronics!"
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Tony Fabris

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#205703 - 19/02/2004 20:29 Re: Smooth Volume Adjust [Re: wfaulk]
Diznario
enthusiast

Registered: 17/10/2001
Posts: 265
Loc: Portland OR
This raises the question of why you've installed a sound system that can go so much louder than you want.

Ha! That is kinda funny, isn't it?

Well actually, it's not usually me that has a problem with it. Couple times now on snowboarding trips we've had somebody sleeping in the back of the car, and then the sombody tries to turn up the music a little bit and WAKEUP! It's actually been kinda funny. But, I'd still like to fix it.

My thinking has always been that it's better to have a system that can handle higher volumes than what you would normally listen to. Generally get a cleaner sound that way, and you're less likely to blow anything if nothing is being stressed.
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Dario
MK2 in an Impreza 2.5RS

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#205704 - 19/02/2004 20:36 Re: Smooth Volume Adjust [Re: tfabris]
Diznario
enthusiast

Registered: 17/10/2001
Posts: 265
Loc: Portland OR
Tony, as always you have supplied more info than any reasonable person would ever need.

But it's all good!

Damn, I had no idea there was so much drama goin on, just for the volume. That's insane.

Yeah, I hope they fix it too.

Thanks for the info!
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Dario
MK2 in an Impreza 2.5RS

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