Flucuating Sound w/Equlizer Enabled

2011-11-06 11:12:55

I've just run into a problem that is really annoying me. When I use the EQ in FB, it has started fluctuating levels. It's hard to explain. It's like the volume is fluctuating, similar to WahWah kinda. I turned everything off, including Replay Gain and all other forms of normalization in Windows. Nothing stops it. W/o the EQ the problem stops, so I think I have it at last correlated to the use Foobar's EQ plugin.

(1) When the EQ is disabled, or (2) the EQ is zeroed but enabled, or (3) the EQ is enabled and auto level is enabled the problem stops.

One other thing too. I can't switch my Playback Device when Foobar is open. I can switch it, but Foobar doesn't accept the change and continues playback from the first device.

I just uninstalled 117 and then fresh installed 119 and I have the same problem. I did use my same presets, though.

Flucuating Sound w/Equlizer Enabled

Reply #1 – 2011-11-06 13:12:53

I guess your OS is Vista or Windows 7 and you are experiencing the effect of the built-in clipping prevention in the Windows audio subsystem. If your tracks are already loud, using positive EQ values is likely to cause the tracks to clip. The "Auto level" feature in the EQ options is intended to prevent this, exactly as you reported. On XP the overly loud output would simply clip and possibly cause audible distortion.

If you prefer to not use "Auto level" you can alternatively reduce the overall volume level simply by using the volume slider or Replay Gain (you can adjust the Replay Gain Preamp settings to keep the overall volume level on the safe side.)

Flucuating Sound w/Equlizer Enabled

Reply #2 – 2011-11-06 22:03:13

Win7 64. Sorry. Was 4AM and I'd been working on it for over an hour when I posted in frustration. The thing is, I've never experienced this before. It just started.

Seems to work fine now. Who knows. I do see an improvement with Dolby Pro Logic off. But last night I turned that off with no resolution.

Thanks.

Flucuating Sound w/Equlizer Enabled

Reply #3 – 2011-11-07 00:06:29

It's mostly specific to foobar2000. Most other audio players and applications don't use floating point sample format for output on Windows Vista and newer, so any distortion their equalizers would cause is limited to clipping. foobar2000, on the other hand, will be passing out > ±1.0 sample values, which Windows will happily normalize to within the range for integer sample formats. That is the fluctuating volume level you hear.

Use the auto level option, that will guarantee that nothing exceeds the integer range. It is 100% equivalent to boosting and then turning the volume down. If you want it louder, turn up your Windows mixer level, or if that's already maxed out, turn up your amplifier or speakers.

Flucuating Sound w/Equlizer Enabled

Reply #4 – 2011-11-07 02:59:33

It's the rear channels that are getting that fluctuation. If I turn them off, the front is fine. And it's garbling more than it is level clipping adjustment. It's random. Sometimes the treble is higher or lower or almost nonexistent, or it's mid or lows, or a combination of everything, then it sounds like fast forward at 1.5+ speed or totally garbled. Totally screwed up. It does it no matter if the EQ is auto or disabled. Actually, I'm starting to think I'm hearing random distortions. I can't nail it down.

I'm also starting to think, by the way things change randomly and the sound they make, that it's a driver issue from Realtek, but then what else is new. Their drivers always suck ass.