Red bars in input display

[mewalden]

First, you people are excellent! I get far better advice for free even about the Behringer UFO than from the people at Behringer, who are getting paid for it. I am a newbie here, so I apologize for stupid questions.

Here is my question:

I am using a Behringer UFO device, into a USB port on a Windows Vista Home Basic system, running on an eMachines box. I recorded a vinyl from an ancient Kenwood KD-34R turntable, and even though I turned down the volume control on the UFO device to the minimum, I still got red bars in the Audacity display, and I do understand that this means that the signal as displayed (default display- I haven't touched any settings for the interface) is clipped out of the display (-1, +1) window.

So, I saved the signal as an mp3, and played it back in Windows Media Player, speakers set about medium volume manually.

My old ears (76 years old) heard good music- no clipping, wow, or anything. I assume that my recording went OK, so that the only problem is that I haven't set the display correctly. Is this correct, and if so, can I rescale that window, and how? If also I am correct about what I see, I think it would be nice to have a feature in Audacity where the window would be dynamically rescaled. That could of course result in a very vertically attenuated display if sporadic loud sounds occurred.

[kozikowski]

I think it would be nice to have a feature in Audacity where the window would be dynamically rescaled.

That might be the last thing you want. The meters are the standard by which you test everything else. If your meters go from-1 through 0 to +1, and you're getting red overload bars, then your sound is too hot. It doesn't have to be knock-you-over damaged, it can cause very slight harshness to the louder passages. Any excursion over +1 is a problem.

Is there any provision to turn it down? I mean other than the computer. Does the USB device have tools or controls or software packages?

You know you need a Phono Preamplifier, right? Sound comes from a raw turntable "damaged" in a very precise manner so the show fits in the grooves and you have to undamage it. That's the RIAA curve or amplifier. What part of your system does that?

Koz

[mewalden]

THanx for reding my question. Here is what I know- not much.

The USB device, which is a Behringer U-Phono UFO-202, has its own preamp, which is one of the reasons I bought it. It has a volume control, which I have turned down as far as it will go. Maybe that control is only for the earphone monitor, I don't know.

The device has no software- Behringer just furnished a copy of Audacity, and an EnergyXT disc, which I tinkered with, but I have no intuition for its interfrace. The Behringer thingy is just plug and play.

The Behringer device has a switch for tape deck vs turntable. When in tape deck mode, as one of your people reminded me (I should have read the UFO manual) the input is extremely faint when used with a turntable. So, I have that switch in turntable mode. There are no other controls on the UFO.

This turntable has no volume control. In fact it has no on off control- just a 33-45 switch, a cut switch, and an up-down toggle for the arm.

I noticed that under Preferences, Interface, there is a box to select Meter / Waveform db range. Mine still has the default of -36 db. Might tinkering with this setting change anything?
What I think you are telling me is that I am wrong about the function of the Audacity window- it is already scaled to normalize. I noticed that

[kozikowski]

Yes, the volume control on the Behringer is for the headphones.

the input is extremely faint when used with a turntable.

And, if you listened to it carefully, it's gutless. No bass at all and very forward treble. That's the distortion -- and it's very precise.

Go into Audacity Preferences and read me the top two Quality lines.

I'm grasping at straws now. If the Behringer is delivering digital audio too hot, there isn't much you can do. That's the down side of digital audio. Once you digitize something wrong, the game is over, most times.

The reason the sound meters don't go above +1 and -1 is there is nothing louder than those two. If you select the Waveform (dB) (track drop-down menu) the timelines go in negative numbers up to zero. They match the bouncing light sound meters.

The cartoon version of that is, given each loudness has a digital value 1000101, 1010001, etc. maximum is where all the one's line up. 1111111. There is no way to get a higher value than that.

There is one way and that's Audacity preference default of 32-bit floating. If you were able to capture sound with that technique, then you may be able to get values over absolute maximum. In that case, you could apply the Amplify tool with a negative number to bring the sound back to normal with no damage at all. That's a lot of moons and stars lining up at the right times. Most people aren't that lucky.

We also have sound cards where I work where the analog overloads before the digital. So we get surgically correct, perfect, sharp, clean digitized masters of crappy audio. Only in digital would that be counted as a success.

As we go.

Koz

[mewalden]

The top two lines read:
Default sample rate 44100 Hz
Default Sample Format 32 bit float.

I don't know what the "Amplify Tool" is.

I tried something else, and it seems to do good things- I won't claim it works:

In the Control Panel, there is an icon which looks like a speaker. I moused it, and, as long as I have the USB Behringer device plugged in, I can see the Audio Codec. I double-click it and bring up the properties sheet. I select the Level tab, and I can adjust the level between 0 and 100 %. It was set by default to 38%. I dabbled with it- 40% makes things much worse. But 30% seems just right- I only get a very few red bars.

I think this music requires a very large dynamic range- it is a mandolin orchestra with deep deep bass and very high treble instruments. I don't think the turntable is damaged, although maybe the old cartridge ( > 30 years old) is too stiff and the lack of compliance has its own artifacts. The thing hasn't been used for about 20 years, and has been well-stored. The vinyl platter itself has very few visible defects, and I think the red bars don't happen where the defects are.

What I'm thinking is that I need some way to acommodate to the dynamic range.

[kozikowski]

Default sample rate 44100 Hz
Default Sample Format 32 bit float.

That's the good news. That means within reason, you can bring the volume down out of the red bar range in post production with little or no damage.

Open one of your overloading shows and Effect > Amplify > New Peak Amplitude, -1.

That should make all the red bars vanish.

I would not capture at a volume where the system produces any red bars. That's insanely dangerous. The volume range on a phonograph record is far worse than the digital system that follows it. Groove noise alone will limit how quiet things get. I don't think you have to worry about the record "not fitting" in the digital file.

Koz