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Echo Cancellation with negative echo tail

  • On May 7, 2017
Background Echo path/tail is one of the most fundamental parameters when performing echo cancellation. In previous posts, we elaborated on the importance of echo tail and we also provided a Do It Yourself (DIY) method to calculate the echo tail. In most usage scenarios, the value of the echo tail will be a positive one […]
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Echo cancellation and public address systems

  • On January 13, 2017
Background When you hear the words echo or echo cancellation, you probably imagine a scenario in which two people are talking over the phone and one of them hears his/her echo. Indeed this is the most common scenario in which echo appears and echo cancellation mechanisms are being used.  In this post we would like […]
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Echo Cancellation with Flash – A Case Study

  • On December 12, 2016
Background From time to time we are getting requests to improve audio quality in flash calls and mainly to help remove echo. In a previous post, Echo Cancellation with Flash Clients, we discussed few techniques that could be helpful. In this post we show a case study for integrating a centralized audio filtering to improve […]
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Echo cancellation is now available for PJSIP

  • On December 12, 2016
Background PJSIP is an is a free and open source multimedia communication library. One of the most important components that influence the audio quality in VoIP communication solutions is the existence of a good echo cancellation.  SoliCall’s acoustic echo cancellation software is a powerful echo cancellation technology that is also flexible to support and tune […]
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Time manipulation and its impact on echo cancellation

  • On December 12, 2016
Background Time manipulation is a known technique in audio processing. It can be used to either compress the audio (resulting in speed-up) or expand the audio (resulting in slow-down). Usually this is done without altering the pitch and therefore without changing the fundamental signature of the voice.
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Why Echo Cancellation for Android is a Difficult Task?

  • On December 12, 2016
Background SoliCall offers different software solutions for audio quality improvements. One of the areas with an increasing demand is the need to solve echo issues with Android devices.  As discussed in few of our previous posts on  echo cancellation, in real-life conditions performing a good echo cancellation is a rather complex task. In addition, it […]
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Audio Quality When Using Speakerphone During Phone Calls

  • On November 20, 2016
  Background There are different scenarios in which calls are made using speakerphones. For example: In manufacturing floor where the employees want to have an open communication channel without the limitation of headset or handset. When using intercom devices. When more than one person needs to listen to the call (e.g. in conference rooms). When […]
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Acoustic Echo Cancellation and Sound Cards

  • On November 20, 2016
Clock Synchronization Acoustic Echo Cancellation (AEC) is a method of removing the echo from the audio signal captured by the microphone. This is done by using the audio that is played to the speakers as a reference audio signal. Most AEC algorithms require that both audio signals, i.e. the signal captured from the microphone and […]
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Noise Reduction and Echo Cancellation for existing VoIP Networks

  • On November 20, 2016
Background Many times we are asked for ways to cancel noise and improve audio quality in existing telephony networks.  The majority of the requests come from call centers and SMBs that are looking for simple plug-and-play solutions to resolve audio quality issues that they are facing.  Since most of these request arise for companies that […]
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Improving Audio Quality with Analog Telephone Adapter (ATA)

  • On November 20, 2016
Background One of the first steps SMBs take towards VoIP is to add ATA to their existing analog telephone network. There are many well known brands of ATAs in the market today like Linksys PAP2, Cisco PAP2T, Grandstream HandyTone and others. Regularly we are requested to improve audio quality in such telephony systems – especially […]
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