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Sample Rate 

 
The rate at which the ADC generates the numbers is equally important in 
determining the quality of a digital recording. To get a high level of 
accuracy when sampling, the sample rate must be greater than twice the 
frequency being sampled. The mathematical statement of this is called the 
Nyquist Theorem. When dealing with full-bandwidth sound (20Hz

20kHz), 

you should sample at greater than 40,000 times per second (twice 20kHz). 
Your Echo hardware allows you to sample at rates up to 96,000 times per 
second.  
 
If the sampling rate is lower than the frequency you are trying to record, 
entire cycles of the waveform will be missed, and the result will not 
resemble the proper waveform. When the sample rate is too low, the 
resulting sound has diminished high frequency content.  
 

 

Figure C. Increased sample rates yield a more accurate reproduction of the 
source signal.  

 
By the way, the circuits that generate the sample rate must be exceedingly 
accurate. Any difference between the sample rate used for recording and the 
rate used at playback will change the pitch of the recording, just as with an 
analog tape playing at the wrong speed. Also, any unsteadiness, or jitter, in 
the sample clock will distort the signal as it is being converted from or to 
analog form.  
 

Содержание LAYLA 24

Страница 1: ...LAYLA 24 LAYLA LapTop LapTop LapTop LapTop MONA MONA LapTop LapTop LapTop LapTop GINA 24 MIA Owner s Manual Version 3 0 for Macintosh Designed and Manufactured in the U S by Echo Corporation...

Страница 2: ...he unit are not undermined This equipment is provided with a cord having an equipment grounding conductor and grounding plug This plug must be plugged into an outlet that is properly installed and gro...

Страница 3: ...Digital Audio Corporation at 805 684 4593 9AM to 5PM Monday through Friday Pacific Time If necessary you will be given a return authorization number Products returned without an RA number will be refu...

Страница 4: ...A24 ONLY 28 INSTALL CUBASIS 32 THE CONSOLE GINA24 LAYLA24 AND MONA 33 RUNNING THE CONSOLE 33 THE CONSOLE WINDOW 33 MENUS 37 SHORTCUTS 37 THE CONSOLE MIA 38 RUNNING THE CONSOLE 38 THE CONSOLE WINDOW 38...

Страница 5: ...d Gina24 only Four mounting screws with collars Layla24 and Mona only An interface cable Layla24 Mona and Gina24 only Please note The cable included with the Gina24 system is a shielded audio cable th...

Страница 6: ...pheral audio equipment such as a mixer microphones studio monitors musical instruments etc Note Echo will not be able to supply technical support for any non Apple brand Macintosh clone computers In a...

Страница 7: ...ve an older Macintosh select Apple System Profiler from the Apple menu Under the System Profile tab look at the section entitled Hardware overview and see what kind of processor you have If it s a Pow...

Страница 8: ...tware Installation The first step is to install the software needed to support your Echo hardware 1 Power up Power up your Macintosh 2 Start the Installer Insert the Installation CD into your CD ROM d...

Страница 9: ...n The installer will now create the folder where you told it to and place the Console the ASIO driver and this manual inside it 4 Installation completed You will now see a message telling you that the...

Страница 10: ...electricity from your body before handling the card This can be done through the use of a grounding strap or more simply by touching your bare hand to the metal casing of the computer s power supply...

Страница 11: ...the installation 8 If you have Mia skip this step Locate the audio interface box Layla24 Mona and Gina24 the interface cable and the power cable Securely mount the interface into your equipment rack L...

Страница 12: ...can now attach external audio devices to the connectors Information on attaching external devices to your particular interface may be found in the following sections 5 Turn on your audio interface bo...

Страница 13: ...rmance with Layla24 it is critical to use the appropriate cabling and connectors Analog Inputs and Outputs Layla24 has eight analog inputs and eight analog outputs on the rear panel The input and outp...

Страница 14: ...t you should only use a replacement cable from Echo ADAT S PDIF Optical I O Next to the COMPUTER connector is a pair of connectors labeled OPTICAL IN and OUT These connectors are used to transmit digi...

Страница 15: ...able S PDIF operation 75 ohm coaxial RG59 video cables are recommended Word Clock Next to the S PDIF ports are the Word Clock connectors These connectors allow you to synchronize one Layla24 to anothe...

Страница 16: ...of connections to the Layla24 interface is for MIDI The MIDI ports can be used for receiving MIDI time code MTC or sending MIDI signals from your digital audio MIDI sequencing software to external so...

Страница 17: ...nnections can accept balanced or unbalanced signals via or XLR connectors Since Mona has built in preamps you can just plug your microphone or guitar cable right into any of Mona s analog inputs No ex...

Страница 18: ...d to any line level equipment or guitars plugged in using connectors Mona s Line Input 1 4 TRS Impedance 10K Trim 0 40dB When a connector is plugged into Mona s universal input jack the microphone pre...

Страница 19: ...the input signal is greater than 3dB or within 3dB of clipping The three yellow bars each represent a range of 3dB and the green bars each represent a range of 6dB For optimal audio quality you should...

Страница 20: ...alog inputs and outputs is a connector labeled COMPUTER This connector is known as a DB 9 and is similar to the serial port on a PC It is the point at which the audio interface connects to the Mona PC...

Страница 21: ...gital data among digital audio devices via an optical signal You can use this port for ADAT 8 channels or for optical S PDIF stereo I O Note Mona is only capable of transmitting or receiving one type...

Страница 22: ...S PDIF operation 75ohm coaxial RG59 video cables are recommended Word Clock Next to the S PDIF ports are the Word Clock connectors These connectors allow you to synchronize one Mona to another Mona L...

Страница 23: ...Gina24 has two analog inputs and eight analog outputs on the front panel The input and output connections can accept balanced or unbalanced jacks via connectors Both the inputs and outputs are set to...

Страница 24: ...he COMPUTER connector is a pair of connectors labeled OPTICAL IN and OUT These connectors are used to transmit digital data among digital audio devices via an optical signal You can use this port for...

Страница 25: ...rs are used to transmit digital data among digital audio devices via an electrical signal S PDIF data can use the full 24 bit sample width used internally on Gina24 When connecting devices to the S PD...

Страница 26: ...r connecting balanced line level signals The three sections of a TRS connector are used to transmit the three components of a balanced signal T plus R minus S ground Mia will also accommodate the two...

Страница 27: ...rogram you have installed You can copy it by dragging it to the desktop or another folder while holding down the option key 3 Move it Put a copy of the ASIO Echo24 file into the ASIO Drivers folder of...

Страница 28: ...e Opcode s OMS 1 Install OMS OMS is included on the CD that came with your Echo product just open the OMS folder and double click the installer 2 Run OMS Setup Now you will need to find the Opcode fol...

Страница 29: ...ayla24 3 Create a New Studio Setup Go to the File menu and click New Studio Setup Click OK A new window will come up Click Search OMS will search for any new equipment and then you should see Layla24...

Страница 30: ...you will see the OMS MIDI Device Setup window 5 Verify that your MIDI devices are recognized This window recognizes any MIDI devices like synthesizers currently attached to your system through your M...

Страница 31: ...n you re done and you ll see a window displaying your new setup 7 Test it If you want to test your new setup go to the Studio menu and click Test Studio Your mouse pointer will turn into a musical not...

Страница 32: ...lled copy the ASIO driver from the Echo folder on your hard disk into the ASIO Drivers folder under the Cubasis folder 4 Configure Cubasis Double click the Cubasis icon From within Cubasis select Opti...

Страница 33: ...de and adjust input monitoring Running the console Once you have run the installer you will find the console in a folder called Echo on your hard drive Double click on the icon labeled Echo24 Console...

Страница 34: ...the currently active bus All monitor controls remain in effect even when not displayed by maintaining a level setting for each monitor path it controls Clicking on an output bus button simply selects...

Страница 35: ...button marked with a G sets the gang mode If you are in gang mode the mute buttons and nominal level buttons will work together for example clicking the mute on one channel activates the mute button o...

Страница 36: ...our record level Also clicking on the readout below the fader will allow you to numerically enter a fader setting The analog inputs also have gang buttons and their operation is the same as the gang b...

Страница 37: ...rmat by selecting File Preferences This lets you configure your card for professional or consumer format S PDIF output Some S PDIF devices need to see one format or another if you are having trouble c...

Страница 38: ...cho on your hard drive Double click on the icon labeled Echo24 Console The console window The basic metaphor for the console interface is a digital mixing board It works in terms of output busses An o...

Страница 39: ...select Let s start with the area within the green outline on the right This is the bus select panel Two different output busses are shown here the analog output bus on top and the digital output bus...

Страница 40: ...t up is the area all the way to the left within the red outline This area is divided up into two vertical strips These are the controls for the analog inputs Since Mia only has two analog inputs only...

Страница 41: ...a s S PDIF inputs Playback strips The area within the orange outline controls the level of audio being played by an application These control the eight virtual outputs that Mia s ASIO driver presents...

Страница 42: ...hanging this setting The Active Card menu is used when you have more than one Mia use this menu to switch between the different cards Shortcuts Shift drag Holding down the Shift key and dragging a fad...

Страница 43: ...tions where sample accurate synchronization is required or that will be affected by clock drift Let s take a brief look at the various synchronization types Word Clock This is a synchronization signal...

Страница 44: ...can send out or master ADAT clock as well slave to it If you want the interface to slave to an ADAT clock just set the input clock to the ADAT setting Layla24 Mona Gina24 can only sync to ADAT clock i...

Страница 45: ...complicated set up You have two Layla24s connected Simply set Layla24 1 to Internal for its input clock Now connect the first Layla24 to the second one via a BNC cable running from Word Clock Out on...

Страница 46: ...nsole With the advent of ASIO 2 0 software programs can control the hardware monitors directly This is called ASIO Direct Monitoring The ASIO driver for Mia supports Direct Monitoring However not all...

Страница 47: ...ent latencies The best method therefore is to mute the monitors in the console and to control your software monitoring from within your audio application No matter which type of monitoring you use if...

Страница 48: ...The last control is labeled Buffer size which allows you to change the buffer size so you can get lower latency Generally a smaller buffer size will result in a lower latency However the speed of you...

Страница 49: ...go up to 96 kHz This in turn presents the ASIO driver with a problem If you re trying to use both Layla24 and Mona at the same time should ASIO applications be allowed to use 96 kHz The solution is t...

Страница 50: ...us plenty of detailed information about your computer system your audio software and the problem you are having We do ask you to please read through this manual and the support area of our website bef...

Страница 51: ...rocessor upgrade card to get your Echo card to work again with your computer Problem You can t get your Echo card to work under OS X Solution The current driver does not support OS X It only supports...

Страница 52: ...he deck is not equipped to handle We have provided a software switch in the driver that allows you to select which mode transmits To access this switch go to the Console In the Options menu select eit...

Страница 53: ...ock This can be done using the Console Problem Layla24 Mona and Gina24 You keep hearing a high pitched squealing sound or your S PDIF or ADAT signal has gone crazy Solution Reset the sample rate of yo...

Страница 54: ...54 Solution Not all plugs are made to the exact same dimensions Try a plug cable from a different manufacturer...

Страница 55: ...nt Echo ASIO drivers One is for the older Echo hardware Layla Gina Darla Darla24 The other is for the new hardware Gina24 Layla24 Mia Mona However you can use multiple cards from either group just not...

Страница 56: ...rate On playback the process happens in reverse The series of numbers is played back through a digital to analog converter or DAC which converts the numbers back into an analog signal This signal can...

Страница 57: ...n be represented by any of over 16 million possible values The output DACs are also 24 bit again over 16 million values are possible The S PDIF inputs and outputs also support signals with up to 24 bi...

Страница 58: ...ing rate is lower than the frequency you are trying to record entire cycles of the waveform will be missed and the result will not resemble the proper waveform When the sample rate is too low the resu...

Страница 59: ...re a signal of 6dB is twice as big as a 0dB signal and a signal of 12dB is four times as big as a 0dB signal Since digital audio signals are represented by binary data each bit of audio information re...

Страница 60: ...r maximum signal level All other signal levels are lower and are expressed as negative decibels Most meters on digital equipment have 0dB at the top and range downward from there A signal that is 30dB...

Страница 61: ...t amplifier will subtract the noise on the minus input from the noise on the plus input If the input amplifier is perfectly balanced and the noise on both plus and minus is precisely equal the noise w...

Страница 62: ...small as 137dBu 7dBu 144dBu or approximately 10 nano volts That s 10 one billionths of a volt Transistors and resistors produce noise in this range just by having electrons moving around due to heat E...

Страница 63: ...Dynamic Range 108dB A weighted THD n 0 001 20Hz 22kHz A weighted Nominal Input Level 4dBu Maximum Input Level 18dBu Input Impedence 10K Analog Outputs x8 balanced TRS Frequency Response 10Hz 22kHz 0 2...

Страница 64: ...balanced analog outputs with high performance 24 bit 128x oversampling digital to analog converters S PDIF digital I O with up to 24 bit resolution ADAT optical digital I O Headphone output with volum...

Страница 65: ...110dB A weighted THD n 0 001 20Hz 22kHz A weighted Nominal Input Level 4dBu Maximum Input Level 22dBu Input Impedence 10K Analog Outputs x8 balanced TRS Frequency Response 10Hz 22kHz 0 25dB Dynamic R...

Страница 66: ...outputs with high performance 24 bit 128x oversampling digital to analog converters S PDIF digital I O with up to 24 bit resolution ADAT optical digital I O Headphone output with volume control On boa...

Страница 67: ...nced XLR EIN 129dBV Input Impedance 1 5K Gain Adjustment 20 60dB Line Input Level balanced TRS Input Impedance 10K Gain Adjustment 0 40dB Guitar Input unbalanced Input Impedance 107K Gain Adjustment 1...

Страница 68: ...converters Six analog outputs both XLR RCA with high performance 24 bit 128x oversampling digital to analog converters S PDIF digital I O with up to 24 bit resolution ADAT optical digital I O Trim con...

Страница 69: ...mic Range 106dB A weighted THD n 0 001 20Hz 22kHz Nominal Input Level 4dBu Maximum Input Level 18dBu Input Impedence 10K Analog Outputs x2 balanced TRS Frequency Response 10Hz 22kHz 0 5dB Dynamic Rang...

Страница 70: ...rsampling analog to digital converters Two balanced analog outputs with high performance 24 bit 128x oversampling digital to analog converters S PDIF digital I O with up to 24 bit resolution On board...

Страница 71: ...bels 60 digital data 60 digital recording 57 digital to analog converter 57 Direct Monitoring 47 49 56 dynamic range 63 E Esync 45 G G3 7 G4 7 G4 Cube 52 guitar input 20 guitar switch 20 H hardware mo...

Страница 72: ...S PDIF recording 52 S PDIF resolution 58 sample rate 57 59 sample size 58 SCMS copy protection 53 selecting a slot 11 software monitoring 47 Sound Manager 52 specifications 64 static electricity disc...

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