One of the many advantages of the new DV format is found in it�s greatly expanded audio capabilities. The Digital Video standard includes Pulse Code Modulation (PCM) audio recording. In conventional analog recording, sound waves are recorded as changes in the magnetic field on the tape. In digital audio recording, sound is recorded as 0 and 1 after it is converted in pulse codes. This is the reason digital audio is referred to as Pulse Code Modulation. The digital audio code (a series of "off or on" signals) is recorded by the drum, on a part of the tape that is separate from the video information. A provision for PCM is part of the 8mm video specifications, however, Canon has not used this optional sound track in any of its 8mm or Hi8 models to date.

Sound waves are vibrations in the air with two basic properties: the first is frequency, from low (bass) to high (treble); the second is amplitude, from soft to loud. Together they form a simple sine wave. The wave�s amplitude is represented by its height; the further the curve swings above and below its center line, the louder the signal. Its frequency can be represented by the number of times per second the wave goes through a complete "cycle". The more cycles per second, the higher the wave�s frequency. The average young human ear can hear frequencies from about 20 cycles per second (20 hertz, or 20 Hz), a very low base tone, to about 20,000 cycles per second. The distance between peaks is the wavelength, which becomes shorter as the frequency rises.

^Amplitude ! ! ! !

Frequency > 1 1 0 1 0 1

The camcorder�s microphone picks up sound and outputs an analog signal consisting of minute voltage changes. This signal is then passed through an analog-to-digital (A/D) converter. In a digital recording, the original sound wave is measured at thousands of sampling points per second, and records those voltage samples as numbers. In playback, the sampling points are recreated, and the audio is processed by a digital-to-analog converter (D/A).

The quality of the reproduction depends on how detailed the blueprint is, and how well the reconstruction is done at the playback end. The amount of detail mainly depends on the number of samples per second (which controls frequency response) and the number of binary digits, or "bits" per sample (which controls noise and distortion).

Most sound waves are complex mixtures of simple sine waves. We only need to record two points per cycle of such a wave�s highest frequency to be able to reconstruct the wave in playback. The sampling frequency (the number of times the signal is measured per second) must be high enough to ensure at least two samples for every wave of every audio frequency�at least 40,000 samples per second for an audio band going up to 20,000 Hz.

Digital systems measure in steps, but the analog signals they�re measuring are continuous. An analog signal that ranges between +1 and -1 volts goes through an infinite range of values between those points, but a digital system can record only a finite number of those values. The more digits it has, the more steps it can distinguish and the more closely it can match its readings to the variations in the original signal. Because digital systems use finite means to record infinite signal variations, some mismatch is inevitable, and every such mismatch adds noise and distortion to the signal.

Digital systems use the same binary numbering systems found in computers; that is, each digit only has two possible values, 0 or 1. Each digit added doubles the number of possible values the system can handle: a one-digit number has two values (0 and 1); a two digit number has four values (00, 01 10, and 11; a three-digit number has eight possible values; and so on.

Every time a digit is added to a digital recording system, the amount of its inaccuracy�and, therefore, its noise and distortion�is cut in half. This increase in accuracy is equivalent to cutting noise and distortion by 6 dB; so you can roughly gauge a digital system�s dynamic range by multiplying its digits, or bits, by six. For example, a fourteen-bit system has 84dB of dynamic range, and a sixteen bit system (such as the compact Disc) has 96 dB.

The number of bits in a system, limits the dynamic range. Slight signal overloads don�t cause slight increases in distortion, as they do in analog. In digital systems, they cause sudden, intolerable distortion. Weak signals, no stronger than the system�s noise, are simply not recorded at all. Even though the digital system�s dynamic range is firmly limited, its limits are far wider than those of most analog systems. At 96 dB, those limits are wide enough to accommodate the entire dynamic range of music.

When you copy a signal, you degrade it. In analog, this limits frequency response and adds noise and distortion. There is no degradation in digital reproduction.

Digital has another virtue�no wow or flutter. The tiny speed variations that cause wow and flutter in analog tape recorders are also present in digital ones, but you never hear them. As samples are read off the recording, they�re fed into a buffer circuit, which smooths out the speed variations.

The device responsible for changing an analog signal into a series of numbers is the analog-to-digital converter. It measures (or "samples") the strength of the changing voltage at regular intervals, generating a steady stream of numbers. Two parameters directly affect the quality of the resulting audio: sample rate and bit depth. The converter�s sample rate dictates how often it measures the signal to generate a new value. The more frequently the converter measures the signal the more accurate the resulting data. Sample rate corresponds directly to frequency response�the highest frequency a digital system will capture is exactly one-half the sample rate. To capture the full audio spectrum up to around 20,000 cycles (or 20kHz), a sample rate of 44.1kHz is common. Higher sample rates make for increased treble response and a more "hi-fi" sound. Low sample rates sound duller and darker.

Bit depth affects how many bits the converter uses for each numerical measurement of the signal. More bits equal a more accurate measurement, which explains why 16-bit CD audio sounds so much better than an 8-bit multimedia sound file. A low bit depth allows the converter the measure the sound with a yardstick marked only in inches. A higher bit depth allows the converter much greater accuracy (a yardstick marked in 1/8^th inch increments, for example).

16 bit (48kHz, 2 channel) for the highest sound quality. "16-bit" refers to the amount of data recorded and the range of the data (16-bit converted to decimal numbers means that there are 65,536 different numbers that can represent any sample). 16-bit represents the most data for the truest and fullest range of sound. DV specifications call for a sampling rate of 48 KHz (48 thousand times per second), 44.1 KHz or 32 KHz. (DAT uses 48KHz sampling and CDs use 44.1 KHz sampling).

12 bit stereo (32kHz, 2 channels) records on two of the four available channels (Stereo 1), leaving two other channels (Stereo 2) available for the addition of sound, music, narration, etc. 16 bit sound produces CD quality, two channel sound on one track. The 12 bit mode divides the audio track into two, recording two channels on one track while leaving the remaining track open for post production audio recording with separate editing gear. In other words, you can add new sound later using a DV VCR. You cannot add new sound to a tape using the XL1.

12-bit stereo (32kHz, 4 channels) for simultaneous recording on four channels (Stereo 1 and Stereo 2). Audio can then be output as 4 independent channels.

With 12-bit, the sound quality is just slightly lower, because the amount of data gathered through the sampling and quantization procedures is lower than with 16-bit (4,096 variations for 12-bit compared to 65,536 for 16-bit). The 12 bit sound is sampled at 32 KHz. Because there is less data, it does not take up all the space available to audio on the tape, resulting in 2 two-channel tracks.

With 12-bit audio, you can use the microphone mounted on the camcorder plus up to two remote microphones, all recording on separate channels, at the same time. At the editing stage, selections can be made for the desired mix for the finished video. Or, if only two channels are used, the original audio can be left on the tape while new audio (music and narration, for example) can be added without erasing the original sound during the editing process.

Unbalanced audio equipment is generally found on consumer camcorders, and indeed all previous Canon camcorder models have used a 3.5mm mini-jack as their input. An unbalanced microphone may work well attached to the camera, however if it�s range is extended, the microphone cable frequently picks up interference from extraneous electro-magnetic fields resulting in hum.

Attaching the MA-100 allows the use of two professional XLR microphones, or two wireless microphone receivers on the XL1. Balanced XLR microphones contain a noise-canceling cable that greatly reduces unwanted interference. The MA-100 converts balanced signals from the XLR microphones to unbalanced signals. The MA-100 includes RCA plugs which can be connected directly to the camcorders RCA audio terminals.

The XL1 records sound in "unlocked" audio. Unlocked audio does not mean out of sync audio. Unlocked audio is always completely in sync with the video. The difference has to do with the number of audio samples per video frame. With locked audio the sample rate per frame of video is fixed, while unlocked audio allows for some slight variations in the number of samples per frame.

The XL1�s 3.5mm Mini Jack is used for the supplied microphone. Audio 1 and Audio 2 refer to the physical location of the audio inputs. The Audio 1 terminals appear on the back of the camcorder, the Audio 2 terminals are on the handle. Stereo 1 and Stereo 2 refer to the stereo tracks available on the tape.

Open the Camera Menu and select AUDIO MODE.

Choose one of the following modes:

16-bit (48KHz, 2 channel (for the highest sound quality)

(Note: 16-bit mode only contains Stereo 1 sound)

12-bit Stereo 1 (32kHz, 2 from 4 channels) for recording on 2 channels

(Stereo 1), leaving 2 channels (Stereo 2) free for you to add new

sound at a later date using a DV VCR. NOTE: you cannot add

new sound to a tape using the XL1 camcorder.

 

Close the menu. The name of your chosen mode is displayed in the

viewfinder and main LCD panel. It is unnecessary to set AUDIO 1 to MIC on

the menu.

Slide the INPUT SELECT switch to MIC.

This assigns the MIC mini jacks as the source for the audio input. You

can use the supplied microphone or attach an external microphone.

or

Slide the INPUT SELECT switch to ATT.

If you are recording in a very loud environment, (at an airport for example)

you may want to use the attenuator. The attenuator reduces loud noises to

produce a more natural sound.

Select the recording level method.

Normally, the camera sets the audio recording level automatically, as long as

the REC LEVEL switch is set to A. You can set the recording level manually:

Slide the REC LEVEL switch of the AUDIO 1/Mic controls to M. (MANU

appears in the audio LCD panel).

Turn the LEVEL dial to adjust the recording level and BALANCE dial to

adjust the balance between the 2 inputs. Check the levels in the audio

LCD panel. Note: you can not adjust the volume level independently for

the left and right channels. We recommend keeping the level below the

12 point index mark, and monitoring the sound using headphones. You

can adjust the headphone volume by rotating the PHONES LEVEL dial.

AUDIO 1 INPUT FOR TWO CHANNEL RECORDING (Stereo 1)

USING RCA JACKS

SOUND SOURCE: VCR, CD or other input device using the RCA terminals

on the back of the XL1, instead of the mini jack.

Open the Camera Menu and select AUDIO MODE.

Choose one of the following modes:

16-bit (48KHz, 2 channel (for the highest sound quality)

(Note: 16-bit mode only contains Stereo 1 sound)

12-bit Stereo 1 (32kHz, 2 from 4 channels) for recording on 2 channels

(Stereo 1), leaving 2 channels (Stereo 2) free for you to add new

sound at a later date using a DV VCR. NOTE: you cannot add

new sound to a tape using the XL1 camcorder.

 

Close the menu. The name of your chosen mode is displayed in the

viewfinder and main LCD panel.

Slide the INPUT SELECT switch to AUDIO 1. This assigns the AUDIO 1 RCA jacks as the source for the audio input.

3. Open the Camera Menu and select AUDIO 1 INPUT. Then choose:

LINE: to record sound from a VCR, CD or other line in devices

4. Select the recording level method.

Normally, the camera sets the audio recording level automatically, as long as

the REC LEVEL switch is set to A. You can set the recording level manually:

Slide the REC LEVEL switch of the AUDIO 1/Mic controls to M. (MANU

appears in the audio LCD panel).

Turn the LEVEL dial to adjust the recording level and BALANCE dial to

adjust the balance between the 2 inputs. Check the levels in the audio

LCD panel. Note: you can not adjust the volume level independently for

the left and right channels. We recommend keeping the level below the

12 point index mark, and monitoring the sound using headphones. You

can adjust the headphone volume by rotating the PHONES LEVEL dial.¹

 

 

 

AUDIO 1 INPUT FOR TWO CHANNEL RECORDING (Stereo 1)

USING RCA JACKS

SOUND SOURCE: XLR type microphones

XLR microphones are attached via the MA-100 Microphone Adapter/Shoulder Pad which contains 2 XLR inputs (L and R). The MA-100 can be plugged into the AUDIO 1 RCA terminals on the back of the camcorder, or AUDIO 2 RCA terminals on the handle.

Open the Camera Menu and select AUDIO MODE, then choose:

16-bit (48KHz, 2 channel (for the highest sound quality)

(Note: 16-bit mode only contains Stereo 1 sound)

12-bit Stereo 1 (32kHz, 2 from 4 channels) for recording on 2 channels

(Stereo 1), leaving 2 channels (Stereo 2) free for you to add new

sound at a later date using a DV VCR. NOTE: you cannot add

new sound to a tape using the XL1 camcorder.

 

Close the menu. The chosen mode is displayed in the finder and main LCD.

If you are using the AUDIO 1 inputs, slide the INPUT SELECT switch to AUDIO 1. This assigns the AUDIO 1 RCA jacks, on the back of the XL1, as the source for the audio input and disables the supplied microphone.

3. Open the Camera Menu and select AUDIO 1 INPUT, then choose:

MIC ATT 20: recording sound using a mic, when the sound level is high

MIC: to record sound using a XLR microphone

Select the recording level method. Normally, the camera sets the audio

recording level automatically, as long as the REC LEVEL switch is set to A.

You can set the recording level manually:

Slide the REC LEVEL switch of the AUDIO 1/Mic controls to M. (MANU

appears in the audio LCD panel).

Turn the LEVEL dial to adjust the recording level and BALANCE dial to

adjust the balance between the 2 inputs. Check the levels in the audio

LCD panel. Note: you can not adjust he volume level independently for

the left and right channels. We recommend keeping the level below the

12 point index mark, and monitoring the sound using headphones. You

can adjust the headphone volume by rotating the PHONES LEVEL dial.¹

(Simultaneous recording of all Four Channels)

SOUND SOURCE: Supplied microphone, external microphone, VCR, CD or

other line in devices, or using XLR type microphones

Four channel recording can be the most versatile configuration. For example, you can input two external wireless microphones and use the supplied microphone all simultaneously.

Open the Camera Menu and select AUDIO MODE.

Select "12 bit ST-1, 2", and close the menu.

"12bit ST-1,2" is displayed in the viewfinder and main LCD panel.

Selecting Audio Mode 12 bit ST-1,2 (32kHz, 4 channels) is for simultaneous

recording on four channels (Stereo 1 and Stereo 2)

To set the input for Stereo 1:

Use the supplied mic or external microphone plugged into the mini jacks

Slide the INPUT SELECT switch to MIC.

This assigns the MIC mini jacks as the source for the audio input. In place of the

supplied microphone, you can attach an external microphone to the mini jacks.

or

Slide the INPUT SELECT switch to ATT.

If you are recording in a very loud environment, you may want to use the attenuator.

The attenuator reduces loud noises to produce a more natural sound.

or

Use the Audio 1 RCA jacks on the back of the camcorder to record sound

from a VCR, CD or other line in device or XLR microphones.

Switch the Input Selector to Audio 1. Open the Camera Menu and select the

appropriate option for AUDIO 1 IN:

LINE: To record sound from a VCR, CD or other line in devices

MIC ATT20: to record sound using a microphone, when the sound level is high.

MIC: To record sound using a XLR microphone attached to the MA-100 Microphone

Adapter/Shoulder Pad.

To set the input for Stereo 2.

Connect a device to the AUDIO 2 RCA jacks on the handle. From the

Camera Menu, select Audio 2 INPUT, then select the appropriate option for

AUDIO 2 IN:

LINE: To record sound from a VCR, CD or other line in device

MIC ATT20: To record sound using a microphone, when the sound level

is high.

MIC: To record sound using a XLR microphone attached to the MA-100

Microphone Adapter/Shoulder Pad.

4. Select the recording level for 4 channel recording

Normally, the camera sets the audio recording level automatically, as long as

the REC LEVEL switch is set to A. You can set the recording level manually:

Set the recording level for stereo 1:

Slide the REC LEVEL switch of the AUDIO 1/MIC controls to M.

Turn the LEVEL dial to adjust the recording level and BALANCE dial to

adjust the balance between the two inputs. Check the levels in the audio

LCD panel. Note: you can not adjust the volume level independently for

the left and right channels. We recommend keeping the level below the

12 point index mark, and monitoring the sound using headphones. You

can adjust the headphone volume by rotating the PHONES LEVEL dial.

b. Set the recording level for stereo 2:

Slide the REC LEVEL switch of the AUDIO 2 controls to M (manual).

Turn the L and R dials to independently adjust the recording levels of the

two inputs (corresponding to the L and R channels of the Audio 2 RCA

jacks). Check the levels for each channel in the audio LCD panel. It is

essential for you to monitor the sound using headphones. Adjust the

headphone volume by rotating the PHONES LEVEL dial. ¹

 

 

 

 

 

 

 

 

Using the Audio Monitor selector is only effective when using 12 bit (Stereo 1 and Stereo 2) mode, since this is the only mode which would have a selection. If you are recording using 16 bit mode or 12 bit (ST1), then the sound is fixed in Stereo 1 only.

Located just below the audio meter, on the left side of the camera, the audio monitor button allows you to select the sound source you want to record:

stereo 1, stereo 2 or a mix of both. Use headphones to monitor the audio while recording. Press the AUDIO MONITOR button to make a sound check. With each press you can cycle through �

ST 1 (Stereo 1 only)

ST 2 (Stereo 2 only)

MIX (Mixture of ST 1 & ST 2 at a ratio of 1:1 is always used in Camera mode)

Your choice is selected a few seconds after you last pressed the button, and shown in the viewfinder and audio LCD panel.

During playback, the XL1 only plays the audio you have selected with Audio Monitor! When playing back a tape in which the audio was recorded in 12 bit (Stereo 1, Stereo 2) mode, you can select the output you would like to listen to. Press the AUDIO MONITOR button to cycle through the selection:

Stereo 1, Stereo 2, or a MIX (1:1) or Variable

When you have chosen the output, STEREO 1, STEREO 2 or MIX will be shown in the top left of the viewfinder and in the audio LCD panel. If you turn the power off, the output (and display) defaults to STEREO 1.

If the sound was recorded in 16 bit mode, it only contains stereo 1 sound and you can not select the audio mix. You also can not select the audio mix if 12 bit stereo 1 mode was used, unless new sound has been added with a DV VCR.

If you select MIX Selection (1:1) a mixing ratio of Stereo 1 to Stereo 2 is 1:1.

If you select MIX Selection .. Variable, a mixing ratio of Stereo 1 to Stereo 2 can be adjusted. For this adjustment, you can use the + (up) and - (down) cursor keys to choose the mix balance (or the ST-1/St-2 MIX BALANCE buttons on the remote control. There are 10 steps displayed on the screen. The center position indicates a mixing ratio of 1:1.

Make sure the camera is set to VCR mode. Open the menu and select the output channel you wish:

In the normal stereo mode, the left-side signal is output at the left channel terminal and the right-side signal is output at the right channel terminal.

If the audio mode is 16 bit or 12 bit Stereo 1, the audio signal will be sent to the RCA jacks labeled L and R.

If you chose Stereo 1 for the output at stage A, Stereo 1 (L&R) will be sent to the RCA jacks labeled Audio 1 (L&R). In addition, stereo 2 (L&R) will be sent to the RCA jacks labeled Audio 2 (L&R). This gives you four independent audio signals.

If you mixed the balance at stage A, the combination of left channels from stereo 1 and stereo 2 will be sent to the left channel of Audio 1 and the combination of the right channels will be sent to the right channel of Audio 1.

L/L Only the left-side signal is output to the RCA left and right jacks. For

reproducing only main voice of bilingual information recorded on other

equipment.

R/R Only the right-side signal is output to the RCA left and right jacks. For

reproducing only sub voice of bilingual information recorded on other

equipment.

L + R/R Gives a mono output. Sound from the left and right channels are combined and sent to the left RCA jack.

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