-G.711: an international standard used for encoding (packetizing) telephone voice at either 56kbs or 64 kbps - this is uncompressed digitized voice.
-G.723: a protocol for compressing voice to 6.4 kbs or 5.3 kbs. The compression quality is very good with voice quality as good as normal telephone voice quality. It is supported by virtually all IP telephone equipment.
-H.323: Signaling & telephone services protocol for the transmission of IP packets representing any combination of voice, video and data. H.323 is designed for operation over existing IP networks. Includes facilities call setup signaling and media control. Allows VoIP equipment to interoperate.
-SIP (Session Initiation Protocol): A signaling & telephone services protocol similar to, but simpler than, H.323.
Tuesday, October 6, 2009
Where will an IP PBX be used?
IP PBXs are good candidates for being used particularly in
-new businesses which will avoid the costs of installing and maintaining two networks (its hard to replace equipment that works in existing offices)
-businesses that have many branches will reduce costs by
avoiding long distance charges incurred by calls between the branches and
using one centralized directory (which will be cheaper to maintain than many multiple directories)
-new businesses which will avoid the costs of installing and maintaining two networks (its hard to replace equipment that works in existing offices)
-businesses that have many branches will reduce costs by
avoiding long distance charges incurred by calls between the branches and
using one centralized directory (which will be cheaper to maintain than many multiple directories)
What are the Advantages of an IP PBX?
Compared to a conventional PBX, an IP PBX
-handles both voice and data,
-is cheaper since it requires only one network to install and maintain instead of two,
-reduces equipment costs (only IP based products; no voice products needed),
-reduces long distance charges for inter-branch office calls (by using the data network),
-is easier to provision (just plug in from wherever),
supports services such as unified messaging,
-is more flexible,
-is more scalable,
-makes it easier to provide new services, such as data and video collaboration,
-allows remote configuration (over the Web), and
-supports modular software upgrades, new technologies (new CPUs, etc.) are easy to incorporate.
-handles both voice and data,
-is cheaper since it requires only one network to install and maintain instead of two,
-reduces equipment costs (only IP based products; no voice products needed),
-reduces long distance charges for inter-branch office calls (by using the data network),
-is easier to provision (just plug in from wherever),
supports services such as unified messaging,
-is more flexible,
-is more scalable,
-makes it easier to provide new services, such as data and video collaboration,
-allows remote configuration (over the Web), and
-supports modular software upgrades, new technologies (new CPUs, etc.) are easy to incorporate.
What is an IP PBX?
A PBX is a customer premises telephone system that manages telephones in the enterprise and acts as the gateway to external voice networks. A switch/router directs incoming packets to the appropriate data network. Traditionally, two separate networks are required: one for voice and one for data.
Instead of two separate networks, one each for data and voice, only one network is needed if voice is packetized (Voice over IP) and sent over the data network.
An IP PBX is a combination of a switch/router and a PBX that handles Voice over IP (VoIP)
In an IP PBX, computers can be on a shared LAN that is connected to the IP PBX. Telephones, on the other hand, should be directly connected to the IP PBX. This avoids Quality of Service (QoS) issues that arise if both computers and telephones are on a shared LAN. In such a case, voice packets will have to compete with data packets for the shared LAN. Poor telephone voice quality will result if voice packets are not transmitted in a timely manner.
An IP PBX also acts as a gateway that provides voice connections (voice lines, T1s) to a LEC, a long distance company, etc. and data connections (cable, DSL, ISDN, E1) to a cable operator, a LEC, an ISP, etc. IP PBXs can be used bypass the circuit-switched telephone network by using the data network to connect to branch offices and other locations on the data network.
Using a single converged network that carries both voice (packetized) and data allows development of new services not typically available on the traditional network - for example, the use of one central directory across multiple locations and unified messaging.
An IP PBX replaces a traditional PBX. It can be used with
Instead of two separate networks, one each for data and voice, only one network is needed if voice is packetized (Voice over IP) and sent over the data network.
An IP PBX is a combination of a switch/router and a PBX that handles Voice over IP (VoIP)
In an IP PBX, computers can be on a shared LAN that is connected to the IP PBX. Telephones, on the other hand, should be directly connected to the IP PBX. This avoids Quality of Service (QoS) issues that arise if both computers and telephones are on a shared LAN. In such a case, voice packets will have to compete with data packets for the shared LAN. Poor telephone voice quality will result if voice packets are not transmitted in a timely manner.
An IP PBX also acts as a gateway that provides voice connections (voice lines, T1s) to a LEC, a long distance company, etc. and data connections (cable, DSL, ISDN, E1) to a cable operator, a LEC, an ISP, etc. IP PBXs can be used bypass the circuit-switched telephone network by using the data network to connect to branch offices and other locations on the data network.
Using a single converged network that carries both voice (packetized) and data allows development of new services not typically available on the traditional network - for example, the use of one central directory across multiple locations and unified messaging.
An IP PBX replaces a traditional PBX. It can be used with
an IP phones (with a built-in DSP chip that converts voices to IP packets and vice versa),
a soft phone (software application on PCs that also converts voice to packets and vice versa), which is used with a headset or a handset,
existing phones along adapters that packetize voice, and
standard phones connected to PCs (PCs acts as the adapters).
As in case of computing devices, IP addresses are automatically assigned to phones as they connect to the system. This means that a telephone can be moved from one location on the network to another. The telephone number remains the same as it associated with the phone.
VoIP packets can be packetized using protocols such as G.711 or G.723:
G.711: an encoding standard for packetized voice; uses 64 kbs and can communicate with other G.711 devices.
G.723: an encoding standard for packetized voice that does compression; uses 6.4 kbs and can communicate with other G.723 devices but not G711 devices.
Saturday, October 3, 2009
How Does VoIP Work?
There are phones practically everywhere and even a typical household may have one for each member of the family. Nowadays, as computers are beginning to take the role as tools to speak to another person, one could wonder how does VoIP work.
VoIP, also known as voice over internet protocol, is a standard of being able to communicate using sound signals using the internet rather than the classic telephone networks. It allows even greater distances to be reached, as all it takes is a computer and software to utilize.
For VoIP, it would definitely replace conventional phone lines in the future, yet how VoIP works would depend on two types of things.
Computers with messenger software like Skype can be used to call anyone's computer who uses the same software. This can be considered as free since a link can be established directly through that software. If calling to a landline or cellphone, there are certain rates apply, and they're usually cheaper in comparison from the regular carriers.
There's also a special phone that utilizes VoIP works the same and even has some special options like caller ID included. These phones work like an ordinary telephone, only being able to call anyone in the world without added costs and if they also have VoIP. These phones are usually found in businesses that specialize in customer care and the like.
There are several answers on how does VoIP works, yet the technicality of it can always be simplified as it is during the invention of the telephone.
By Elija James
VoIP, also known as voice over internet protocol, is a standard of being able to communicate using sound signals using the internet rather than the classic telephone networks. It allows even greater distances to be reached, as all it takes is a computer and software to utilize.
For VoIP, it would definitely replace conventional phone lines in the future, yet how VoIP works would depend on two types of things.
Computers with messenger software like Skype can be used to call anyone's computer who uses the same software. This can be considered as free since a link can be established directly through that software. If calling to a landline or cellphone, there are certain rates apply, and they're usually cheaper in comparison from the regular carriers.
There's also a special phone that utilizes VoIP works the same and even has some special options like caller ID included. These phones work like an ordinary telephone, only being able to call anyone in the world without added costs and if they also have VoIP. These phones are usually found in businesses that specialize in customer care and the like.
There are several answers on how does VoIP works, yet the technicality of it can always be simplified as it is during the invention of the telephone.
By Elija James
All About VoIP
Voice over Internet Protocol or the VoIP, is basically the process of sending voice through internet protocol, making it convenient for a consumer to make phone calls at cheaper price. VoIP is used not only when using the internet protocol to send or receive calls, but it is also useful when you want to avail the service of traditional phone lines that guarantee better quality & allow bigger space for calls.
When the quality of audio and frequency in VoIP is high, it is very hard for customers to notice the difference between it and a normal telephone. Even the person who is receiving the calls from a VoIP will not be able to guess that the calls are made from a VoIP Network. Transferring PSTN (Public Switched Telephone Network) to VoIP/SIP Session Initiation Protocol) allows VoIP users to send and receive phone calls as done in ordinary phone lines.
Now, enough about VoIP from the scientific point of view. Let us now proceed to the benefits of using VoIP compared to using conventional phone lines. Basically, consumers care mostly about the rates so they would like to know how much can be saved when you purchase a VoIP service. This is one of the advantages of VoIP. It became popular because of its cheap call rates as compared to any conventional phones. It gives you the ability to make unlimited phone calls, long distance calls and low international calls charges with low monthly subscription rate. This is value added service for any consumer.
VoIP can be used in different ways. One possible way is through ATA or Analog Telephone Adapter. ATA is connected between a telephone jack that is already existent and an IP network in order to provide VoIP service. This type of service is generally offered by broadband internet providers such as cable companies and telephone companies.
Simply check the company that provides you with internet cable service or the company that provides your home phone service to see if they offer this service. If you want an easier way, just check the internet out for low rates companies. There are a lot of new companies that are just providing this service and they are concerned about giving the best service with lower rates.
Finally, a VoIP is a better & more economical way of making long distance as well as short distance calls by simply using an internet connection. You can use it for local, nationwide and international calls. You can even make calls to residential phones or cell phones.
By Joanne Greco
When the quality of audio and frequency in VoIP is high, it is very hard for customers to notice the difference between it and a normal telephone. Even the person who is receiving the calls from a VoIP will not be able to guess that the calls are made from a VoIP Network. Transferring PSTN (Public Switched Telephone Network) to VoIP/SIP Session Initiation Protocol) allows VoIP users to send and receive phone calls as done in ordinary phone lines.
Now, enough about VoIP from the scientific point of view. Let us now proceed to the benefits of using VoIP compared to using conventional phone lines. Basically, consumers care mostly about the rates so they would like to know how much can be saved when you purchase a VoIP service. This is one of the advantages of VoIP. It became popular because of its cheap call rates as compared to any conventional phones. It gives you the ability to make unlimited phone calls, long distance calls and low international calls charges with low monthly subscription rate. This is value added service for any consumer.
VoIP can be used in different ways. One possible way is through ATA or Analog Telephone Adapter. ATA is connected between a telephone jack that is already existent and an IP network in order to provide VoIP service. This type of service is generally offered by broadband internet providers such as cable companies and telephone companies.
Simply check the company that provides you with internet cable service or the company that provides your home phone service to see if they offer this service. If you want an easier way, just check the internet out for low rates companies. There are a lot of new companies that are just providing this service and they are concerned about giving the best service with lower rates.
Finally, a VoIP is a better & more economical way of making long distance as well as short distance calls by simply using an internet connection. You can use it for local, nationwide and international calls. You can even make calls to residential phones or cell phones.
By Joanne Greco
VoIP Security - Why VoIP Providers Are More Secure
Up until recently, the issue of security for VoIP hasn't been one that has received a great deal of attention. However, as the growth of 'verbal emails' continues and VoIP becomes increasingly popular particularly amongst business users, it is an issue that has to be addressed.
Using a VoIP provider gives you more of a measure of security than relying on freeware systems available on the Internet. The primary defence mechanism of any computer is the firewall. Providing a barrier between your computer or network and security threats such as hackers and viruses, a firewall offers a degree of protection that filters data going in and out of your network. As VoIP works by breaking voice messages into digital data, a standard firewall installed in your PC may not be enough to offer you full protection. VoIP providers have much more stringent firewalls installed on their main servers, which protects the entire network and all machines linked into that network. This is one of the primary reasons why, if you're serious about using VoIP on a regular basis, it's best to sign up with a bona fide VoIP provider.
Passwords are an essential part of Internet life, and VoIP should be considered as no different to any other secure operation you carry out on your computer. Authentication is the best way to ensure that those using the system are authorised to do so and that you don't have any unauthorised access to your system. Unfortunately, very few VoIP providers actually have this facility, so it's best to hunt around for providers that do offer you this additional layer of protection.
You should also inquire if your VoIP provider offers an encryption service. If a data packet (the broken down information that flies across the ether) is intercepted by a third party, it is of no use whatsoever to them if they can't read it. An encryption facility secures the data by changing it into an unintelligible form which is translated or decrypted at the receiving end, making sure that your VoIP call is as secure as possible. Again, your VoIP provider should be able to tell you if they offer an encryption service to paying customers.
Without a rethink and some serious security protocol implementations, VoIP will find it difficult to make inroads into the lucrative commercial market. It is this aspect that VoIP providers are now focusing their efforts on, rather than the clarity of calls, for example. VoIP security needs to be addressed as part of the overall context of Internet security. At present, private branch exchanges (PBX) are replaced by server-based IP PBXs running on the ubiquitous Microsoft Windows operating system. This system has shown itself to be vulnerable to attack from hackers and an attack on a VoIP server could result in the loss of potentially sensitive data. Therefore, it is important that equipment is properly protected, and the best way for the individual user to have this assurance is to use a legitimate VoIP provider.
VoIP gateways are potentially one of the weakest links in the chain. When VoIP is used on an external network, gateway technology converts the data package from the IP network into voice before sending them over a public telephone network. The concern is that at this point, VoIP can be hacked by unscrupulous users to gain access to free calls. The trick to prevent this lies, once again, through password protection and making sure that the gateway is configured in such a way as to ensure that only people with the correct access codes are permitted to make and receive VoIP calls.
All of these weaknesses within the system are best addressed by using a dedicated VoIP provider who has the appropriate firewalls, authorisation and encryption facilities to make sure your data is as well protected as possible. There will always be a number of determined hackers who may attempt to access VoIP calls, but minimising the possibility by placing your trust in an experienced and professional provider is the best way to thwart all but the most determined of attacks.
By Costas Kariolis - Online Marketing Manager of Vonage UK.
Using a VoIP provider gives you more of a measure of security than relying on freeware systems available on the Internet. The primary defence mechanism of any computer is the firewall. Providing a barrier between your computer or network and security threats such as hackers and viruses, a firewall offers a degree of protection that filters data going in and out of your network. As VoIP works by breaking voice messages into digital data, a standard firewall installed in your PC may not be enough to offer you full protection. VoIP providers have much more stringent firewalls installed on their main servers, which protects the entire network and all machines linked into that network. This is one of the primary reasons why, if you're serious about using VoIP on a regular basis, it's best to sign up with a bona fide VoIP provider.
Passwords are an essential part of Internet life, and VoIP should be considered as no different to any other secure operation you carry out on your computer. Authentication is the best way to ensure that those using the system are authorised to do so and that you don't have any unauthorised access to your system. Unfortunately, very few VoIP providers actually have this facility, so it's best to hunt around for providers that do offer you this additional layer of protection.
You should also inquire if your VoIP provider offers an encryption service. If a data packet (the broken down information that flies across the ether) is intercepted by a third party, it is of no use whatsoever to them if they can't read it. An encryption facility secures the data by changing it into an unintelligible form which is translated or decrypted at the receiving end, making sure that your VoIP call is as secure as possible. Again, your VoIP provider should be able to tell you if they offer an encryption service to paying customers.
Without a rethink and some serious security protocol implementations, VoIP will find it difficult to make inroads into the lucrative commercial market. It is this aspect that VoIP providers are now focusing their efforts on, rather than the clarity of calls, for example. VoIP security needs to be addressed as part of the overall context of Internet security. At present, private branch exchanges (PBX) are replaced by server-based IP PBXs running on the ubiquitous Microsoft Windows operating system. This system has shown itself to be vulnerable to attack from hackers and an attack on a VoIP server could result in the loss of potentially sensitive data. Therefore, it is important that equipment is properly protected, and the best way for the individual user to have this assurance is to use a legitimate VoIP provider.
VoIP gateways are potentially one of the weakest links in the chain. When VoIP is used on an external network, gateway technology converts the data package from the IP network into voice before sending them over a public telephone network. The concern is that at this point, VoIP can be hacked by unscrupulous users to gain access to free calls. The trick to prevent this lies, once again, through password protection and making sure that the gateway is configured in such a way as to ensure that only people with the correct access codes are permitted to make and receive VoIP calls.
All of these weaknesses within the system are best addressed by using a dedicated VoIP provider who has the appropriate firewalls, authorisation and encryption facilities to make sure your data is as well protected as possible. There will always be a number of determined hackers who may attempt to access VoIP calls, but minimising the possibility by placing your trust in an experienced and professional provider is the best way to thwart all but the most determined of attacks.
By Costas Kariolis - Online Marketing Manager of Vonage UK.
VOIP Service and Emergency Phone Numbers
The general assumption about VOIP service was that you could not call emergency numbers using internet phone service. This was considered to be a draw back of VOIP but if you had visited Axvoice site, you would have to change your mind.
VOIP service is already winning great appreciation from its customers spread all around the world. The amazing features offered by Axvoice at a real low cost prove that they understand the user needs and requirements far better than others.
Internet phone service not only provides unlimited local, international calls at remarkably low rates, but also provides its customers with E911 service. Whenever you need to call a police station or fire brigade, all you need is an internet connection and a VOIP service provider.
Now comes the question how they made this possible. The simple story is that when you dial 911 using your Axvoice internet phone service, the call is instantly, routed through our system to emergency response services. Your up-to-date registered information, which includes your full name and address, is already stored in their database, against the number you are calling from, while, emergency operators, with access to your information, send help right away and call back in case of further assistance, if necessary. When a user signs up with them, they dutifully forward that information to the emergency help centers, so that emergency responders reach you at that address, in times of need.
I have observed that Axvoice is the most user-friendly cost effective service both for residential and business users. As a user of this service I can assure you that a non-techno-savvy person can also enjoy it without a twinge.
By Stefen Clark
Working As Asterisk Engineer in Axvoice
VOIP service is already winning great appreciation from its customers spread all around the world. The amazing features offered by Axvoice at a real low cost prove that they understand the user needs and requirements far better than others.
Internet phone service not only provides unlimited local, international calls at remarkably low rates, but also provides its customers with E911 service. Whenever you need to call a police station or fire brigade, all you need is an internet connection and a VOIP service provider.
Now comes the question how they made this possible. The simple story is that when you dial 911 using your Axvoice internet phone service, the call is instantly, routed through our system to emergency response services. Your up-to-date registered information, which includes your full name and address, is already stored in their database, against the number you are calling from, while, emergency operators, with access to your information, send help right away and call back in case of further assistance, if necessary. When a user signs up with them, they dutifully forward that information to the emergency help centers, so that emergency responders reach you at that address, in times of need.
I have observed that Axvoice is the most user-friendly cost effective service both for residential and business users. As a user of this service I can assure you that a non-techno-savvy person can also enjoy it without a twinge.
By Stefen Clark
Working As Asterisk Engineer in Axvoice
What is Voice Over Internet Protocol(VoIP)
VoIP (Voice over Internet Protocol) is an IP telephony term for a set of facilities used to manage the delivery of voice information over the Internet. VoIP involves sending voice information in digital form in discrete packets called SIP(Session Initiation Protocol, a signaling protocol, widely used for controlling multimedia communication sessions such as voice and video calls / conferences over Internet Protocol (IP)). rather than by using the traditional circuit-committed protocols of the public switched telephone network (PSTN). A major advantage of VoIP and Internet telephony is that it avoids the tolls charged by ordinary telephone service. VoIP has become very popular means of communication nowadays, given the advantages it possesses. It is too fine-tuning and is gaining popularity day by day and one day replace the traditional phone everything.
VoIP gives the abilty to go hosted on highly expensive PBX with many advantages like;
• Enjoy mobility and flexibility of operations with multiple geographic and non-geographic numbers for global operations.
• Plug-and-play service modules enable all types of deployment to deploy dramatic upscaling of operations in a matter of hours.
• Hosted solutions enable customers to fully utilize a full-blown infrastructure by employing micro-level, incremental, pay-per-use investment model. 123+
• Enterprises with multiple points of geographic presence can utilize managed business services to have inter-office connections at no cost.
• Enjoy International calling at nominal investments when compared with conventional solutions.
• Do away with the need to maintain leased circuits between the offices & to maintain expensive legacy PABX systems.
• Ability to connect corporate offices spread over multiple geographic locations to work as a cohesive unit with our hosted solution.
• Value added features for corporate businesses, especially contact centers, like voice mail, call forwarding and call transfer between various branches.
• Seamless and uniform VoIP termination for all offices, whether local or international.
VoIP gives the abilty to go hosted on highly expensive PBX with many advantages like;
• Enjoy mobility and flexibility of operations with multiple geographic and non-geographic numbers for global operations.
• Plug-and-play service modules enable all types of deployment to deploy dramatic upscaling of operations in a matter of hours.
• Hosted solutions enable customers to fully utilize a full-blown infrastructure by employing micro-level, incremental, pay-per-use investment model. 123+
• Enterprises with multiple points of geographic presence can utilize managed business services to have inter-office connections at no cost.
• Enjoy International calling at nominal investments when compared with conventional solutions.
• Do away with the need to maintain leased circuits between the offices & to maintain expensive legacy PABX systems.
• Ability to connect corporate offices spread over multiple geographic locations to work as a cohesive unit with our hosted solution.
• Value added features for corporate businesses, especially contact centers, like voice mail, call forwarding and call transfer between various branches.
• Seamless and uniform VoIP termination for all offices, whether local or international.
Monday, July 20, 2009
Master Antenna Television System ( MATV )
What is a Master Antenna System?
MATV stands for Master Antenna Television. It is the means by which many apartment houses1 hotels, schools and other multi-unit buildings distribute TV and FM signals to a number of receivers. In order to accomplish this without a loss of signal quality, these systems must be carefully planned and engineered through the effective use of MATV equipment and techniques.
An MATV system is basically a network of cables and specially designed components that process and amplify TV and FM signals and distribute them from one central location . If there were 100 TV sets in a building, it would be extremely expensive to Install and maintain l00 separate antennas. Not only would It be unsightly, but reception would suffer because that many antennas would interact with each other, causing interference problems.
The MATV system concept can be separated into two divisions: the Head End and the Distribution System
The Head End normally consists of an antenna Installation to receive the desired signals to, processing equipment to filter the signals and remove interference, and a distribution amplifier to amplify the signals to the level required to provide an adequate signal to every receiver in the system. Antenna amplifiers, traps, filters, antenna mixing units, and UHF converters are among the equipment used in t~is portion of the system.
A welt-designed Distribution System is necessary to guarantee that an adequate signal will be delivered to every receiver. It should provide a clean signal to the sets by isolating each receiver from the system and by delivering the proper amount of signal to each set. This portion of the system consists of trunk lines, splitters, feeder lines, and tapoffs. Some of the other equipment used includes tine taps, variable isolation wall taps, coaxial cable, and band separators.
It is important to design your distribution system first. Usually, the requirements of the distribution system will determine the type and size of the amplifier that will be necessary at the head end. The actual layout of the system, of course, will depend upon the dimensions and requirements of the building in which it Is installed.
MATV stands for Master Antenna Television. It is the means by which many apartment houses1 hotels, schools and other multi-unit buildings distribute TV and FM signals to a number of receivers. In order to accomplish this without a loss of signal quality, these systems must be carefully planned and engineered through the effective use of MATV equipment and techniques.
An MATV system is basically a network of cables and specially designed components that process and amplify TV and FM signals and distribute them from one central location . If there were 100 TV sets in a building, it would be extremely expensive to Install and maintain l00 separate antennas. Not only would It be unsightly, but reception would suffer because that many antennas would interact with each other, causing interference problems.
The MATV system concept can be separated into two divisions: the Head End and the Distribution System
The Head End normally consists of an antenna Installation to receive the desired signals to, processing equipment to filter the signals and remove interference, and a distribution amplifier to amplify the signals to the level required to provide an adequate signal to every receiver in the system. Antenna amplifiers, traps, filters, antenna mixing units, and UHF converters are among the equipment used in t~is portion of the system.
A welt-designed Distribution System is necessary to guarantee that an adequate signal will be delivered to every receiver. It should provide a clean signal to the sets by isolating each receiver from the system and by delivering the proper amount of signal to each set. This portion of the system consists of trunk lines, splitters, feeder lines, and tapoffs. Some of the other equipment used includes tine taps, variable isolation wall taps, coaxial cable, and band separators.
It is important to design your distribution system first. Usually, the requirements of the distribution system will determine the type and size of the amplifier that will be necessary at the head end. The actual layout of the system, of course, will depend upon the dimensions and requirements of the building in which it Is installed.
Tuesday, January 27, 2009
Amplifier
Peavey CS800S is an 800 watt power amplifier
· The amplifier receives the combined or mixed signal from the mixer.
· The amplifier is the last component in the sound system before the speaker. Generally, the sound signal progresses through the sound system as follows:
o Microphone or Instrument
o Mixer
o Compressor (optional)
o 31-Band Graphic Equalizer (or parametric equalizer)
o Digital Delay (only for remote speakers that must be time-aligned with the main speakers)
o Cross-Over (only in the case of bi-amped or tri-amped speaker systems or a sub-woofer)
o Amplifier
o Speaker(s)
· The amplifier supplies the power to drive the speakers.
· Most speaker systems, especially lower power speakers only require a single amplifier. However, some speaker systems are designed to work bi-amped or tri-amped. In the case of a bi-amped system, two amplifiers are needed, one for low frequency sounds and one for high frequency sounds. In the case of tri-amped, three amplifiers are needed for low, midrange, and high sounds. If a sub-woofer is used for very low sounds, another amplifier is needed for it.
· Separate amplifiers are needed for the Main System, remote speakers (if required), and the Monitor System.
· When multiple monitor mixes are used, each mix requires its own amplifier.
· In order for an amplifier to make the sound twice as loud, it must supply four times as much power. For example, it takes a 400 watt amplifier to be twice as loud as a 100 watt amplifier.
· Always use an amplifier capable of supplying more power than you need. Distortion increases dramatically when an amplifier is operated at its maximum power. Having plenty of "head room" or reserve power reduces the chance of distortion.
· It is important that an amplifier have very low background noise. Even a small amount of "hiss" can be very objectionable.
· The power rating of the amplifier and the speakers must be similar to reduce the chance of damaging the speakers.
· The amplifier receives the combined or mixed signal from the mixer.
· The amplifier is the last component in the sound system before the speaker. Generally, the sound signal progresses through the sound system as follows:
o Microphone or Instrument
o Mixer
o Compressor (optional)
o 31-Band Graphic Equalizer (or parametric equalizer)
o Digital Delay (only for remote speakers that must be time-aligned with the main speakers)
o Cross-Over (only in the case of bi-amped or tri-amped speaker systems or a sub-woofer)
o Amplifier
o Speaker(s)
· The amplifier supplies the power to drive the speakers.
· Most speaker systems, especially lower power speakers only require a single amplifier. However, some speaker systems are designed to work bi-amped or tri-amped. In the case of a bi-amped system, two amplifiers are needed, one for low frequency sounds and one for high frequency sounds. In the case of tri-amped, three amplifiers are needed for low, midrange, and high sounds. If a sub-woofer is used for very low sounds, another amplifier is needed for it.
· Separate amplifiers are needed for the Main System, remote speakers (if required), and the Monitor System.
· When multiple monitor mixes are used, each mix requires its own amplifier.
· In order for an amplifier to make the sound twice as loud, it must supply four times as much power. For example, it takes a 400 watt amplifier to be twice as loud as a 100 watt amplifier.
· Always use an amplifier capable of supplying more power than you need. Distortion increases dramatically when an amplifier is operated at its maximum power. Having plenty of "head room" or reserve power reduces the chance of distortion.
· It is important that an amplifier have very low background noise. Even a small amount of "hiss" can be very objectionable.
· The power rating of the amplifier and the speakers must be similar to reduce the chance of damaging the speakers.
Equalizer
· Why is equalization needed?
o To increase gain before feedback.
o To compensate for Acoustical problems in the room.
o To tailor the tonal quality of the performance.
· Always start with no equalization (all controls set "flat").
o Equipment manufacturers design their equipment to be used with NO EQUALIZATION.
o Only use equalization to eliminate problems (i.e. feedback, too much bass, too sharp, etc.).
o After the problems are eliminated, there is seldom a need to change equalization to enhance the sound.
· Room factors which may require equalization:
o Sound reflections off of hard surfaces (walls, ceilings, and floors) causes uneven frequency response because of out-of-phase reflections (i.e. drop a stone in a pond and watch the ripples as they hit the shore and reflect back).
o Sound absorption by soft surfaces (seats, people, acoustic treatment) causes loss at high frequencies.
o Every room is different! Some seem to increase high frequencies, others absorb highs. Some resonate with base, others seem to have no bottom end at all.
· Individual channel equalization on the Mixer.
o Adjust for differences in different types of Mikes.
o Adjust for specific instruments (keyboard, guitar, sax).
o Adjust to optimize sound for particular voices (men, women).
o Eliminate feedback points unique to one Mike.
o Reduce breath noise and "pops".
o Compensate for "proximity effect" when performer "eats the mike".
· Monitor equalizer
o Adjust to increase gain before feedback.
o Eliminate "hollow" or "ringing" sound.
· Main System equalizer
o Adjust tonal quality of main speaker system to compensate for room acoustics (texture of walls, floors, or ceiling).
o Only if necessary, adjust to increase gain before feedback.
· Automatic Feedback Eliminator
o This is a special type of equalizer which "listens" for feedback, determines its frequency, and automatically sets a narrow notch filter to eliminate it. Multiple notch filters are set at different feedback frequencies.
o To increase gain before feedback.
o To compensate for Acoustical problems in the room.
o To tailor the tonal quality of the performance.
· Always start with no equalization (all controls set "flat").
o Equipment manufacturers design their equipment to be used with NO EQUALIZATION.
o Only use equalization to eliminate problems (i.e. feedback, too much bass, too sharp, etc.).
o After the problems are eliminated, there is seldom a need to change equalization to enhance the sound.
· Room factors which may require equalization:
o Sound reflections off of hard surfaces (walls, ceilings, and floors) causes uneven frequency response because of out-of-phase reflections (i.e. drop a stone in a pond and watch the ripples as they hit the shore and reflect back).
o Sound absorption by soft surfaces (seats, people, acoustic treatment) causes loss at high frequencies.
o Every room is different! Some seem to increase high frequencies, others absorb highs. Some resonate with base, others seem to have no bottom end at all.
· Individual channel equalization on the Mixer.
o Adjust for differences in different types of Mikes.
o Adjust for specific instruments (keyboard, guitar, sax).
o Adjust to optimize sound for particular voices (men, women).
o Eliminate feedback points unique to one Mike.
o Reduce breath noise and "pops".
o Compensate for "proximity effect" when performer "eats the mike".
· Monitor equalizer
o Adjust to increase gain before feedback.
o Eliminate "hollow" or "ringing" sound.
· Main System equalizer
o Adjust tonal quality of main speaker system to compensate for room acoustics (texture of walls, floors, or ceiling).
o Only if necessary, adjust to increase gain before feedback.
· Automatic Feedback Eliminator
o This is a special type of equalizer which "listens" for feedback, determines its frequency, and automatically sets a narrow notch filter to eliminate it. Multiple notch filters are set at different feedback frequencies.
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