Telos Z/IP ONE Скачать руководство пользователя страница 36 | Manualshive

Страница: 36 / 89

background image

THE STATUS SCREENS |

29

7

The Status Screens

The Z/IP ONE has seven screens of information reporting the current state of different systems in the codec. You can
reach these displays from the main menu by either selecting the Status item or pressing the ESC key on the keypad. A
status screen will also be shown when there is no user activity on the front panel interface.

When status is displayed, you can cycle through screens by turning the main control knob. Return to the main menu by
pressing the ESC key.

The section titles in this chapter match the labels used in the Setup->System->Default Status Page menu item, for ease in
selecting a default.

7.1 Overview

The first screen displays broad information on a number of systems. At the top of the display are level meters for the
transmitted and received (decoded) audio. The left channel is at the top, with the right channel under it. To the left of the
meters is an indicator of what audio input is currently being used. This is especially useful when input failover is enabled.
The icons have the following meanings:

Beneath the meters are items reminiscent of illuminated indicators. A filled (lit) circle indicates a normal operating
condition:

♦

Connect – shows whether the Z/IP ONE is currently connected to any other codec

♦

LAN / WAN – indicates Ethernet LINK status

♦

ZIP – When lit, the Z/IP ONE is logged into the ZIP Server

♦

RcvLock – When the decoder is locked, this indicator lights. This is useful for troubleshooting:

¸

RcvLock, but no Connect: Local loop mode is on. Disable it in the Audio I/O menu

¸

RcvLock and Connect, but no Rcv meters: Silence is decoded. Check audio Xmt meters on remote unit

¸

Connect but no RcvLock: Network conditions make the encoded audio unusable (too much loss, a firewall
blocks packets, frames corrupted in transit, etc)

♦

Livewire – the LAN interface has available Livewire streams

♦

LW Sync – The Z/IP ONE’s Livewire clock has synchronized with the time base of the Livewire network on the
LAN interface

«
...
34
35
36
37
38
...
»

Содержание Z/IP ONE

Страница 1: ...TELOS Z IP ONE Intelligent Zephyr IP codec with Agile Connection Technology USER S MANUAL Manual v2 0 1 for software version 2 0 1r and higher August 2014 ...

Страница 2: ...nual In the past many good ideas from users have made their way into software revisions or new products Please contact us with your comments Service You must contact Telos before returning any equipment for factory service We will need the serial number located on the back of the unit Telos Systems will issue a Return Authorization number which must be written on the exterior of your shipping cont...

Страница 3: ... TO AVOID ELECTRIC SHOCK DO NOT PERFORM ANY SERVICING OTHER THAN THAT CONTAINED IN THE OPERATING INSTRUCTIONS UNLESS YOU ARE QUALIFIED TO DO SO REFER ALL SERVICING TO QUALIFIED PERSONNEL THIS INSTRUMENT HAS AN AUTORANGING LINE VOLTAGE INPUT ENSURE THE POWER VOLTAGE IS WITHIN THE SPECIFIED RANGE THE SYMBOL IF USED INDICATES AN ALTERNATING CURRENT SUPPLY WARNING THE PRODUCT S POWER CORD IS THE PRIMA...

Страница 4: ...to cause interference If it does the user will be required to eliminate the interference at the user s expense NOTE Objectionable interference to TV or radio reception can occur if other devices are connected to this device without the use of shielded interconnect cables FCC rules require the use of shielded cables CANADA WARNING This digital apparatus does not exceed the Class A limits for radio ...

Страница 5: ...the Studio Unit 11 3 2 Power 11 3 3 Audio Inputs balanced analog 11 3 4 Audio Outputs balanced analog 12 3 5 Network Interfaces 12 3 6 USB Ports 12 3 7 Network Interfaces 12 3 8 USB Ports 13 3 9 Parallel Control 13 4 TheFrontPanelInterface 15 4 1 Front Panel Controls 15 4 2The User Interface and Menu System 17 5 TheAudioI OMenu 19 5 2 Input Mode 20 5 3 Microphone level Gain 20 5 4 Line level Gain ...

Страница 6: ...rk Interface Status Screens 31 7 5Version Info 32 8 TheWebInterface 33 8 1 Status Page 33 8 2 Connect 34 8 3 Audio Streaming GPIO and System 35 8 4 Network 35 8 5 Software Management 35 8 6 Quick Start and Manual 36 8 7 Logs 36 9 AudioStreams 37 9 1Telos Session Control Protocol 37 9 2 N ACIP Session Initiation Protocol 40 9 3 Real timeTransport Protocol 41 10 MakingConnections 43 10 1 Dialing Man...

Страница 7: ...n Available IP Address without a DHCP Server 60 Duplicate IP Addresses 61 Network AddressTranslation 62 Appendix B AudioCodingReference 65 History 65 Basic Principles of Perceptual Coding 66 MPEG 69 MPEG4 AAC Advanced Audio Coding 69 AAC LD AAC Low Delay 72 MPEG 4 High Efficiency AAC HE AAC previously known as aacPlus 74 MPEG 4 Enhanced Low Delay AAC 74 ISO MPEG Layer 2 74 G 722 74 aptX and aptX E...

Страница 8: ...tions The Z IP ONE has an impressive list of features including Analog line professional or microphone input levels AES EBU digital input and output 15 volt phantom power for direct use with condenser microphones Transmission bit rates from 8kbps to 2304 kbps User friendly front panel interface with OLED screen Real time metering and connection status display screen Context sensitive on screen hel...

Страница 9: ......

Страница 10: ... you may want to use later For now we ll want the Z IP ONE itself AC power cord and a network cable all included with the Z IP ONE To test the Z IP ONE you ll also need 1 Headphones or connect the Z IP ONE s audio output to an audio monitor 2 Microphone or audio source optional 3 An Internet connected Local Area Network with DHCP Server You may set your Z IP ONE s network configuration manually if...

Страница 11: ...not running at least v2 0 0r please update your codec to the latest released version of software The latest version is always listed and available for download here http www telos systems com codecs zip one If the front panel controls are not used for a short period of time the display will revert back to a status screen by default the last status screen viewed 2 3 SetupWizard One option for initi...

Страница 12: ...Status The top Status screen should show WAN connected Within a few seconds the ZIP light should come on too The ZIP indicator is your assurance that your Z IP ONE is communicating with the Telos ZIP Server and that connections to other Z IP ONEs and Zephyr IPs are just two button presses away What if the ZIP indicator doesn t light up This condition is usually caused by a very restrictive network...

Страница 13: ...ically to the main Status display The large Connect indicator should come ON quickly followed a few seconds later by the RcvLock indicator The Rcv audio level meters will begin showing moving audio levels In a few more seconds the Buffer and Quality gauges in the lower third of the screen will show relative indications of receive buffer size at both ends and quality of the connection indicating dr...

Страница 14: ...ess on your network assigning a fixed ZIP Server Listen Port in the ZIP Server menu and configuring a port forward from the Internet side of your firewall router to the static IP address of your Z IP ONE using that same Listen Port number We suggest you choose a listen port in the 20000 21000 range to avoid port conflicts Left unassigned as in this Quick Start the Z IP ONE negotiates a listening p...

Страница 15: ...given connection or use A full discussion of audio coding is in Appendix B Audio Coding Reference but the following tables summarize their features at a glance Codec Features CODEC Mono Stereo Lower Bit Rates Lower Delay Remote Broadcasts STL Infrastructure Error Concealment Highly Compatible AAC ELD M S ü ü ü ü AAC HE M S ü ü ü AAC LD M S ü ü ü AAC M S ü ü Layer 2 M S ü ü G 722 M ü ü ü ü G 711 M ...

Страница 16: ... awesome especially at 256 kbps and higher Layer 2 112 384 kbps Excellent quality at medi um high bitrates Very com patible with other brands of equipment Music or voice at medium bitrates to other brands of codecs Layer 2 is a great choice espe cially for compatibility across different brands of codecs G 722 64 kbps Good voice quality 7 kHz when low delay and compat ibility is needed Also called ...

Страница 17: ......

Страница 18: ...e the unit is booting Subsequently the main menu will appear This process can take about 90 seconds 3 3 Balanced Analog Inputs Input Audio XLR Pinout PIN DESCRIPTION 1 Ground 2 Signal Input 3 Signal Input Install the left and right analog audio cables in the female XLR connectors marked CH 1 In and CH 2 In on the rear panel The analog audio section accepts audio input with a peak level of 22dBu In...

Страница 19: ... Z IP ONE must be placed behind a firewall These are commonly included in network address translating routers commonly called either NAT routers or simply routers The Z IP ONE conjunction with the ZIP server on the public Internet has technology for automatically creating connections without requiring port forwarding on most styles of NAT routers For more information on these topics see Chapter 9 ...

Страница 20: ... ground inputs and outputs There are 8 open collector outputs and 8 open collector inputs each configurable from the Settings menu on the user interface The DB 25 connector is pinned out as follows PIN FUNCTION 1 5 Volts DC 400 mA max 2 Output 0 3 Output 1 4 Output 2 5 Output 3 6 Output 4 7 Output 5 8 Output 6 9 Output 7 10 No Connection 11 No Connection 12 No Connection 13 No Connection 14 Input ...

Страница 21: ......

Страница 22: ... the volume the display will indicate which audio is present on the headphones Main Control Knob Rotating the Z IP ONE s control knob moves the cursor It also has a push to click function Pressing the knob selects the highlighted menu selection or accepts the current value the setting that is being edited ESC Button This button escapes from the currently selected menu or dialog screen While editin...

Страница 23: ...e Connection Buttons On the right side of the front panel the Z IP ONE has three buttons labeled AUTO CONN and DISC for setting up and dismissing connections The function of each of these keys is as follows AUTO gives you quick access to your phone book This screen displays the current status of other Z IPs so that you can see if they are available before you call Pressing AUTO or the control knob...

Страница 24: ...u you can access the Status Phonebook Audio I O Setup Help and call History sub menus Getting Help Context sensitive help is available at any time by pressing the 1 button General help can also be accessed by choosing Help from the main menu Clearing Pop ups When a condition exists that requires attention the Z IP ONE will display a pop up box in front of whatever screen is otherwise active To clo...

Страница 25: ......

Страница 26: ...ewire outputs set the Z IP ONE s source number to 0 In addition to selecting the audio source to transmit this menu allows you to configure your Z IP ONE for redundant audio inputs to help protect against failures To use this feature select either the AES EBU failover or Livewire failover option When using Livewire failover the Z IP ONE will prefer Livewire audio if it is available If it is not fo...

Страница 27: ...ng a call However be aware that in many codecs changing the stereo mode does change the available range of bit rates After changing the stereo mode the codec setup page will automatically show the new bit rat range available for the selected codec For an at a glance display of all codecs and how they are affected by the transmit mode see the Audio configura tion webpage 5 6 AES EBU Output Sample R...

Страница 28: ... The options are LAN Port WAN Port WiFi WLAN appropriate USB device must be installed UMTS EVDO appropriate USB device must be installed 6 1 Network The WAN Interface menu sets the following options for the WAN RJ45 on the back panel WAN DHCP Off or On WAN IP Address Only used when DHCP is off WAN subnet mask Only used when DHCP is off WAN Gateway IP Only used when DHCP is off WAN DNS Server IP On...

Страница 29: ...ion uses a SIP server to make VoIP calls Contact your SIP server administrator for the values to enter in these fields or leave them blank not to use your own SIP server N ACIP SIP calls may also be made via direct dial to the remote codec s IP address without involving a SIP server Registrar Hostname allows entry of alphanumeric text Registrar User Name allows entry of alphanumeric text Registrar...

Страница 30: ...is problem turn on Router Mode and connect a laptop to the LAN port of the Z IP ONE Set the LAN interface on the Z IP ONE and the laptop s Ethernet controller to be on a private network together Set the laptop s gateway to the Z IP ONE s IP address For example Z IP ONE Settings LAN IP Address 192 168 3 10 LAN Subnet Mask 255 255 255 0 Gateway leave blank Laptop Settings LAN IP Address 192 168 3 11...

Страница 31: ...o allow management of multiple Z IP ONEs that are behind a router that supports port forwarding but not port translation 6 2 Audio Codec The Audio Codec menus allow the user to change various settings related to the audio and transmission quality and also to select the appropriate compression scheme For more detailed information on audio encoding and the codecs used in the Z IP ONE see Appendix B ...

Страница 32: ... to fine tune your connection and audio fidelity Your choice of codec will affect the available range of usable rates The more you restrict this range the more consistent the audio quality will be but with less ability to accommodate bad network conditions For codecs which do not support ACT the maximum bitrate is always used Maximum Buffer and Minimum Buffer these two numbers specify the minimum ...

Страница 33: ...ens Default Status Page chooses one of the main status displays to show when there is no front panel activity See Chapter 7 for more information on the status displays 6 4 Software The Setup Software submenu allows you to choose between two different installed versions of the Z IP ONE s software The last option Reset to Defaults and Reboot will erase all custom settings and phone book entries When...

Страница 34: ... Visibility Choose whether the Z IP ONE is visible to everyone in the directory only people in the same group or no one at all A hidden Z IP ONE can still be dialed by anyone who knows its name and group but will not show up in any directory listings ZIP Server Name Use this field to enter the name of the ZIP Server you will be connecting to Telos maintains a server at zip telos systems com which ...

Страница 35: ... Output Bit 1 8 Sets what status information is reflected on each of the output pins Bit 0 3 GPO the Z IP ONE s eight GPIO signals can be on the parallel port or over Livewire Since Livewire GPIO comes in bundles of five inputs and five outputs the Z IP ONE uses the first four pins of two separate Livewire GPIO addresses If a GPO source is specified here the first four inputs are taken from this L...

Страница 36: ...er it To the left of the meters is an indicator of what audio input is currently being used This is especially useful when input failover is enabled The icons have the following meanings Beneath the meters are items reminiscent of illuminated indicators A filled lit circle indicates a normal operating condition Connect shows whether the Z IP ONE is currently connected to any other codec LAN WAN in...

Страница 37: ... The meaning of each of the in and out bits is configurable on the Setup Parallel Port Configuration page The indicators are active filled or lit when the associated GPIO bit is also active asserted or logically true See Chapter 12 Ancillary Data for more information on GPIO operation 7 3 Call Status Codec The information on this screen again relates mostly to a call in progress The peer and statu...

Страница 38: ...hey are set statically Lastly the first field is highlighted for the primary streaming interface At the top right the interface status is displayed This can be one of the following UP RUNNING the interface is fully configured the link is active and there are no configuration problems that can be determined automatically No Cable the link is down No DHCP yet the interface is configured to use DHCP ...

Страница 39: ...ware and the current software version It also shows whether or not the aptX codec is licensed Our customer service personnel may ask for the information on this screen to assist in troubleshooting your Z IP ONE Older Z IP ONEs like the one shown may not indicate a serial number This is expected ...

Страница 40: ...se to the web interface using the Z IP ONE s IP address followed by a colon followed by the new port number For example if your Z IP ONE is at address 192 168 1 140 and the HTTP port is set to 8810 you would enter its address in your web browser as http 192 168 1 140 8810 From the Z IP ONE web interface you can configure all of the options that are available on the front panel plus a few that are ...

Страница 41: ...xx yy zz SIP via server sip localuser SIP via server sip remote host tld SIP direct sip ww xx yy zz RTP direct rtp ww xx yy zz Below the Direct Dial line is a list of any connections that have been made since loading the Autodial application You can save items from this list to the phone book Starting a connection from this tab will take you to the status tab automatically The Status tab shows inf...

Страница 42: ...ormation see Section 6 1 Network 8 5 Software Management This menu allows you to update the software contained in the Z IP ONE to back up and restore its settings and to enter an aptX license key The Z IP ONE stores two banks of software Using this you may for example test a new version of software while retaining the qualified version You may choose which bank of software is current by selecting ...

Страница 43: ...s an alternative to manual software updating and configuration management the Z IP ONE is fully compatible with the Axia iProbe network management software 8 6 Quick Start and Manual This link opens a PDF copy of the Quick Start guide Chapter 2 in this manual or the whole manual in your browser window 8 7 Logs Where the status page is focused on regular usage statistics the Logs page displays usag...

Страница 44: ...ions can be made with or without the assistance of a directory server They are point to point connections that transfer audio in both directions Like all the Z IP ONE s connection modes TSCP allows you to use different codecs and bit rates in each direction A server is configured and maintained by Telos Systems as a service to our Zephyr IP customers It provides a set of tools to enhance the funct...

Страница 45: ...ed to change the group passwords later if needed and should never be given to anyone Click the Create Group button to create the group A message will indicate if the operation succeeded or failed If the group creation failed due to a duplicate name you will need to change the name and try again Using the name of your organization possibly followed by the city name for a large organization may be m...

Страница 46: ...e static The ZIP Server setup screen on the Z IP ONE has a field for setting a static listen port for this purpose Media Relay Service Not all NATs behave the same way Some NATs are very restrictive and go to great lengths to prevent data from outside the network from reaching devices on the inside This is a great security feature for PCs which typically ini tiate connections themselves However it...

Страница 47: ...IP PBX so the calls may be routed through the PBX A SIP server acts a bit like the ZIP Server passing information to its clients so that they may make connections to each other SIP server details are entered on the front panel under Setup Network SIP Server on the Network web page If you use a SIP server enter the hostname or IP address of the SIP server as the Registrar Hostname and then your log...

Страница 48: ...ams at once Although RTP streams are push only you can transfer audio in each direction To do this the operator of each codec must send an RTP stream to the other If this is done your Z IP ONE will have all the connection features including Agile Connection Technology and remote quality information as if the transfer was started via TSCP or SIP However since the call is not handled by a connection...

Страница 49: ......

Страница 50: ... information all in the first field For SIP and RTP calls the group field is ignored Next select the call type from the list in the third field After the information is entered pressing the Call button will start the connection From theWeb Page All calls are made from the Connect application on the web page For direct dialing use the Connect tab Calling in this way is a little different from using...

Страница 51: ...ooses how many attempts are made to automatically redial or if the Z IP ONE should try to redial forever It can also be set to use whatever the system default redial setting is in the Setup System menu Lastly you will have the option to Save or Save with Codec Both save the details to your phone book but the second option takes a snapshot of the current settings in System Audio Codec and saves the...

Страница 52: ...on group members When you click the Browse button the list will again become selected and active The shortcut keys to jump to a character in the list work for this list as they did for the group list Once you choose a device the cursor will jump to the Add button Click this and you will be taken to the phone book entry edit screen This is the same screen used for manual dialing but with all the de...

Страница 53: ...u all of your Z IP ONE s incoming and outgoing calls are kept in a list arranged by time with the most recent calls first Each entry in the list is preceded by an arrow An arrow to the right pointing to the entry means the call was from this Z IP ONE to the device indicated An arrow to the left pointing to from the entry means the call was from the other device to this Z IP ONE A device name prefi...

Страница 54: ... highlight Streaming Interface and press the control knob Change the option to WiFi WLAN and then press the control knob again to accept the change 4 Press the ESC key twice to return to the status screen Once the WiFi interface is configured and can be used to access the network the ZIP indicator will fill in This indicates that your Z IP ONE is connected to the Internet and is ready to use 11 2 ...

Страница 55: ... a compatibility list that is of any use Some devices on some carriers may still work it is worth trying However for the best chance of compatibility we now recommend the use of Cradlepoint wireless data to Ethernet bridges Cradle point specializes in wireless accessory compatibility and works seamlessly with a Z IP ONE Choose a model that converts wireless data to wired Ethernet and you can set y...

Страница 56: ...ctor on the back panel that provides contact closures close to ground inputs and outputs In addition the Z IP ONE supports Livewire GPIO While only one of these may be used for inputs at any given time the outputs are always available on both interfaces PARALLEL PORT PIN LIVE WIRE PORT LIVEWIRE BIT FUNCTION 1 5 Volts DC 400mA maximum 2 GPI 1 1 Output 1 3 GPI 1 2 Output 2 4 GPI 1 3 Output 3 5 GPI 1...

Страница 57: ...ain threshold This includes both lost packets and packets that arrive with errors rendering them unusable The threshold is user definable the setting for which can be found on the same front panel and web pages as the status bit assignments This output is updated once every three seconds Status Inputs The eight general purpose inputs can each be set to one of six operating modes 1 No function the ...

Страница 58: ... ground An equivalent schematic for the outputs is shown below If you wish to interface directly to 5 volt logic inputs the outputs include a pull up resistor to 5 volts If you need a logic high greater than 5 volts you may supply an external pull up resistor 2 2kΩ to 10kΩ is appropriate to the voltage level required by your external logic inputs You cannot use a voltage level less than 5V however...

Страница 59: ...s status output bits configure it to follow the GPIO using the following syntax sometimes referred to as GPIO snake ww xx yy zz Where ww xx yy zz is the IP address of the Z IP ONE s LAN port and is the number of its GPIO e g 172 16 1 140 1 Use a port of 1 for status bits 1 4 and port 2 for bits 5 8 To use Livewire for input signaling configure a source to follow on either the Setup Parallel Port C...

Страница 60: ... its parallel port it is sent to the Livewire GPIO node s input and is presented to the Livewire network as a Livewire GPI signal Other Livewire products that are interested in a device s status OUTPUT changes listen to the GPIO node s INPUT changes The reverse direction works in a similar manner The GPIO node subscribes to another node s GPI In response it triggers its parallel port output and ge...

Страница 61: ... a computer or laptop a null modem will be required The serial port on the communicating device should be set to 9600 bits per second 8 data bits no parity and one stop bit 9600 8N1 Plug the USB to serial adapter into either of the Z IP ONE s USB ports In a moment a message will appear on the display informing you that the adapter is ready to use When the adapters are installed in both Z IP ONEs m...

Страница 62: ...called IPv4 and that is what we refer to in this manual IPv6 is a newer standard that is not yet widely deployed IPv4 addresses consist of a 32 bit number To make it easier for humans to describe IP addresses are written in a form called dotted decimal notation To come up with a dotted decimal representation the 32 bit number is broken down into four parts each 8 bits long Each part is converted t...

Страница 63: ...y written out in dotted decimal notation just like an IP address If you write it out as a binary number you will notice that it consists of a string of ones followed by a string of zeroes The ones indicate they mask the network portion of the IP address while the zeroes indicate the host portion An example might explain this better Using the same IP address as above 192 168 1 65 with a subnet mask...

Страница 64: ...8 0 0 0 to 191 255 255 255 255 255 0 0 C 192 0 0 0 to 223 255 255 255 255 255 255 0 Class C is the most common IP address class so most of the subnet masks you see will likely be 255 255 255 0 It is possible to have different subnet masks in addition to the ones above The one thing to remember is that when converted to a binary number subnet masks are always a continuous string of 1s followed by a...

Страница 65: ... broadcasts a request for IP configuration information on the subnet If a DHCP server is available it will allocate an unused IP address from a user specified range and respond back to the device The device can then configure itself with this IP address Using DHCP is a convenient method to configure an IP device but it is not always the best course of action When you use DHCP you don t know the as...

Страница 66: ...indicates that this PC was configured for DHCP so there must be a DHCP server available IP Address 192 168 123 101 IP address assigned by the DHCP server Subnet mask 255 255 255 0 This is the network mask for this subnet We can use the same network mask for the Z IP ONE Default Gateway 192 168 123 254 Another important entry we can use the same gateway address on the Z IP ONE DNS Servers 69 75 169...

Страница 67: ...r numbers for no particular reason For this example I chose 10 so my first IP address to test will be 192 168 123 10 1 Press and hold the windows key then press R to bring up the windows Run dialog box Type cmd without quotes in the dialog and press enter You can also launch cmd from the start menu but the steps to do this vary between versions of Windows 2 In the command prompt type ping followed...

Страница 68: ...AP that you are using this address Read the following section for the gory details Duplicate IP Addresses Duplicate IP addresses can be difficult to diagnose Some PCs may give you a warning at boot up that the currently configured IP address is in use But other times duplicate IP addresses are only discovered when an IP device behaves strangely For example you know you assigned a particular IP add...

Страница 69: ...hat there is a NAT device in between Are all NAT devices the same Not all NAT devices are the same as there is no defined standard on how a NAT should behave Each vendor implements the NAT functions in a proprietary manner You may hear NATs described as full cone restricted cone port restricted cone or symmetric Not everyone agrees on the exact definition of these terms A Wikipedia article http en...

Страница 70: ...pes of NATs without requiring any special configuration of the NAT But some NATs are much more restrictive than others Establishing a connection becomes even more difficult when both ends are behind very restrictive NATs Port forwarding can help in these cases If at least one of the sides uses port forwarding then a direct connection can be established much faster You can use port forwarding with ...

Страница 71: ......

Страница 72: ...ample rate of at least twice the desired bandwidth so 15 kHz audio requires after a safety margin 32 kHz sampling Each bit of sample depth represents slightly more than 6dB of dynamic range The first practical coding methods used a principle called ADPCM Adaptive Delta Pulse Code Modulation This took advantage of the fact that it takes fewer bits to code the difference or delta between successive ...

Страница 73: ...s called masking have been discovered in the human auditory system These masking effects which merely prove that our brain is also doing something similar to bit rate reduction have been found to occur in both the frequency and time domains and can be exploited for audio data reduction Most important for audio coding are the effects in the frequency domain Research into perception has revealed tha...

Страница 74: ...time domain resolution de creases simultaneously owing to an inevitable side effect of the band filtering process higher frequency resolution requires a longer time window which limits time resolution Happily masking works also in the time domain A short time before and a longer time after a tone is switched on and off other signals below a threshold amplitude level are not noticeable Filter banks...

Страница 75: ...d to a lower bit rate in the quantization and coding section On the one hand the quantization must be sufficiently coarse in order to not exceed the target bit rate On the other hand the error must be shaped to be under the limits set by the masking curve The quantized values are joined in the bit stream multiplex along with any side information Doing audio coding effectively means managing severa...

Страница 76: ... is not much used Layer 2 is widely used for Digital Audio Broadcasting DAB in Europe audio for video and broadcast play out systems Layer 3 which Telos was the first to use in the Zephyr is widely used in broadcast codecs and has gone on to sig nificant Internet and consumer electronics fame under the moniker derived from the file extension MP3 MPEG2 opened the door for new work and some minor im...

Страница 77: ...oding when there is a noticeable signal pattern like high tonality Perceptual Noise Shaping allows a finer control of quantization resolution so bits can be used more efficiently Because it uses this modular approach an implementer may pick and choose among the component tools to make a product with appropriate performance complexity ratios Or new modules can be developer later and plugged in to i...

Страница 78: ...de If a frame is easy then the unused bits are put into a reservoir buffer When a frame comes along that needs more than the average amount of bits the reservoir is tapped for extra capacity Ancillary Data the bit reservoir buffer offers an effective solution for the inclusion of such ancillary data as text or control signaling The data is held in a separate buffer and gated onto the output bit st...

Страница 79: ...data apply directly to the application of professional codecs to remotes so it is interesting to take a peek over the shoulder of the telecom guys to see what they have learned For broadcast remotes we try to arrange our system so that there is no path for the field announcer s voice to return to his her headphones Nevertheless sometime echo is unavoidable For example this can happen when a teleph...

Страница 80: ...however audio quality scales up with bit rate and transparent quality can be achieved AAC LD s coding power is roughly the same as Layer 3 meaning that mono high fidelity 15kHz audio may be sent at 64kbps At 128kbps you achieve near CD quality stereo audio Delay in perceptual codecs is dependent on several parameters Framelength Timeisrequiredtocollectallthesamplesforaframe Thelongertheframe themo...

Страница 81: ...it s easier and less expensive to implement particularly at the encoder and practical devices using it were available earlier than Layer 3 It s a preferred choice for applications where very large data capacity is available such as satellite links high capacity Primary ISDN or T1 circuits and hard disk storage systems using Ethernet for signal distribution We include it in the Z IP ONE to offer co...

Страница 82: ...nly for speech This is why music transmitted via G 722 has a distinctly fuzzy quality G 722 has a frequency response extending to 7 5 kHz with fairly poor fidelity Unless there is no alternative it should not be used for music aptX and aptX Enhanced Like G 722 aptX also dates from the earliest days of audio coding and is also based on ADPCM However it is designed to run at much higher bit rates wi...

Страница 83: ......

Страница 84: ...dB Output Clipping 22dBu Output Impedance 50 Ohm differential Input Impedance 6K Ohm differential Analog to Digital Converter 24bits Digital to Analog Converter 24bits Physical Height 43 7 mm 1 Rack Unit per EIA RS 310 C Width 482 6 mm 19 per EIA RS 310 C Depth 180 mm Weight 2 5 kg 5 lb Power 115Vac00 240 VAC 50 60 Hz 14 2Watts Temperature 0 40C 32 104 F stirred air Humidity 0 98 relative non cond...

Страница 85: ......

Страница 86: ...se of an uninterruptible power supply UPS with all of our Products Telos products are to be used with registered protective interface devices which satisfy regulatory requirements in their country of use This Warranty is void if the associated equipment was purchased or otherwise obtained through sales channels not authorized by Telos EXCEPT FOR THE ABOVE STATED EXPRESS WARRANTY TELOS MAKES NO WAR...

Страница 87: ...m the end user s location Telos will then in its sole discretion repair or replace the warranted Product at Telos expense Telos also reserves the right if it is not economically justifiable to repair the warranted Product to offer a replacement product of comparable performance and condition direct to the customer at a discounted price accepting the failed warranted Product as a trade in The end u...

Страница 88: ...Water and Moisture Do not use this product near water 7 Attachments Do not use any attachments not recommended by the product manufacturer as they may cause hazards 8 Power Sources This product must be operated from the type of power source indicated on the marking label and the installation instructions If you are not sure of the type of power supplied to your facility consult your local power co...

Страница 89: ...ed If liquid has been spilled or objects have fallen into the product If the product does not operate normally following operating instructions If the product has been exposed to rain or water If the product has been dropped or damaged in any way When the product exhibits a distinct change in performance outside of normally operating specifica tions 17 Replacement Parts When replacement parts are ...

Отзывы:

Нет отзывов

Похожие инструкции для Z/IP ONE

Бренд: Calistair Страницы: 44

Бренд: Daavlin Страницы: 13

Бренд: Daavlin Страницы: 27

Бренд: Baker Instrument Company Страницы: 24

Бренд: Parker Research Corp Страницы: 3

Бренд: S.I.T.A. Страницы: 32

Бренд: Oemtools Страницы: 4

Бренд: Tacx Страницы: 2

Бренд: C.E. Nierhoff & Co Страницы: 7

Бренд: Malekko Страницы: 2

Бренд: Major Страницы: 26

Бренд: Twiflex Страницы: 5

SciCan STATIM 2000S

Бренд: Coltene Страницы: 45

Бренд: Chroma Страницы: 198

Бренд: Landoll Страницы: 40

INSPIRE Mulit-gym M2

Бренд: Hammer Страницы: 26

Бренд: Ibiza Страницы: 40

Бренд: ABI Attachments Страницы: 17

Бренды по названию

0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Популярные бренды

Загрузить еще бренды