Introduction

In today’s interconnected world, reliable voice communication is essential for businesses, individuals, and service providers. Whether it’s a mobile call or a VoIP conversation, ensuring high-quality voice transmission is crucial. Enter Sevana QualTest, a cutting-edge solution designed to evaluate voice quality and network performance. In this article, we’ll explore the features, use cases, and metrics associated with QualTest.

Features of Sevana QualTest

  1. Mobile Test Probe: QualTest serves as a mobile test probe, compatible with Android-powered devices. It seamlessly integrates into both cellular and VoIP networks, allowing comprehensive testing.
  2. End-to-End and Single-Ended Testing: QualTest offers flexibility by supporting both end-to-end and single-ended call testing. Whether you need to assess the entire communication path or focus on specific segments, QualTest has you covered.
  3. User-Friendly Frontend: The intuitive frontend simplifies test setup. Users can specify calling and called parties, reference audio, and devices effortlessly. The frontend also provides real-time insights during testing.
  4. Detailed Reporting and Analysis: QualTest generates comprehensive reports, including overall quality Mean Opinion Score (MOS) over different time periods. It highlights successful and failed test calls, aiding troubleshooting efforts. Additionally, the system can analyze call audio contents using speech-to-text engines.
  5. Compatibility: QualTest works with both rooted and unrooted mobile phones. Analysis can be performed directly on the mobile device or on connected devices (e.g., Raspberry Pi for regular unrooted phones).

Use Cases

  1. Mobile Operators: QualTest empowers mobile operators to monitor call quality across their networks. By identifying bottlenecks and issues, operators can enhance user experience.
  2. Telecom Service Providers: Telecom providers leverage QualTest to assess voice quality in cellular and VoIP networks. It helps them optimize their services and maintain customer satisfaction.
  3. Telecom Solution Providers: Solution providers integrate QualTest into their offerings, ensuring robust voice quality testing for their clients.
  4. Test Engineers: QualTest is a valuable tool for test engineers involved in call quality assessment. It aids in diagnosing network-related problems and optimizing voice services.

Metrics and Analysis

  1. Network Metrics: QualTest measures critical network parameters, including Round-Trip Time (RTT), jitter, and packet loss for VoIP calls. These metrics directly impact call quality.
  2. Mean Opinion Score (MOS): QualTest calculates MOS scores, providing a quantitative measure of voice quality. Users can choose between reference audio or real call audio for MOS estimation.
  3. Waveform Analysis: By analyzing waveforms, QualTest correlates audio problems with network conditions. This helps pinpoint issues affecting voice quality.

Conclusion

Sevana QualTest is a game-changer in the field of voice quality assessment. Its versatility, detailed reporting, and compatibility make it indispensable for telecom professionals. Whether you’re an operator, service provider, or test engineer, QualTest ensures crystal-clear voice communication in an ever-evolving digital landscape.


Note: If you’d like to learn more about Sevana technologies or schedule a call with their development team, feel free to reach out!


Sevana: Contact Us: QualTest

Call center agents quality monitoring: do you have a call center that records customer calls and your agents complain about call quality?

Figuring out call quality issues, problematic routes might be much easier with Sevana PVQA technology.
Setting up massive call recording analysis is a matter of a couple of minutes. In return one receives audio quality score (MOS) and report on audio impairments that influenced the call quality.
By the end of the analysis, you will have full picture on the calls that had most of the problems in quality and potential reasons for them. Interested in receiving this information in real-time? This just simple with PVQA technology implemented for real-time traffic analysis. Contact us for more information.

Call quality issues maintenance prior your cusotmers complain

Do you want to know about call quality issues prior your customers start complaining?

Sevana libraries collect all the QoS and QoE data of the calls in real-time, providing immediate alerting on changes that affect callers’ perception, and discover and store reasons for call audio degradation. Map audio impairments on network metrics and discover QoE and QoS patterns, specific to certain routes, destinations, originations, or parts of the traffic.

Every call, analyzed by the system, creates big data that one can study, using data analysis tools, to predict network behavior and call quality.

How to find call issues that affect callers’ perception?

Sevana PVQA analysis detects and informs about such annoying problems inside the call audio as:

VAD clipping – this impairment detects incorrect work of Voice Activity Detector (VAD). Detector finds edges of active and inactive fragments of the signal considering VAD worked too late (in the beginning of the speech) or too early (in the end of the speech).

Clicking – is a single energy spike in the spectrum of the audio, which may happen for different reasons.
Audio gaps – is a zero-signal level inside speech, a gap in speech that may be caused by different reasons.
Dead air – is a constant signal level inside speech and may have positive and negative value.
Noise – this means that noise level present in the call affects human perception and disturbs the caller.

… and will also let you discover patterns of impairments specific to certain suppliers, partners, or other networks:

Click + DeadAir-01 – high probability that packet loss affected the call audio
Click + VAD clipping – possible packet loss

Caller quality of experience measurement. Do you know about issues bothering your callers that you might not know?

Sevana PVQA technology detects these impairments to predict caller’s quality of experience aside from network quality of service:

💡 Silent Call – one leg of the voice call has no speech (silentcall)

💡 Echo – this is typically due to a blockage or mismatch, which results in the signals bouncing back from where they came. Additionally, the presence of echo effect in packet switched networks can be traced back to the functionality of the line. Where standard lines function with a delay of 10 milliseconds, packet switched networks can have up to 400 milliseconds of delay. As a result, the echo effect is much more noticeable.

💡 Amplitude clipping – is typically a result of a misconfigured voice gateway on the voice path.

💡 Dynamic clipping – notifies about possible clipping happening in another network as the audio waveform corresponds amplitude clipping, however, it is not present at the moment.

These and other impairment detectors allow you an effective caller quality of experience measurement. Contact us to learn more.

 

What are Sevana call quality testing offerings?
We are happy to offer all kinds of tools to test call quality in any network: VoIP, GSM, 5G, satellite
🔹 Vast call quality monitoring both on audio and protocol levels
🔹 Passive real-time and active scheduled call quality analysis
🔹 Call quality problem root cause analysis
🔹 Reliable network and payload MOS
🔹 Mobile-to-mobile call quality tests

contact center end-to-end voice quality testing
Contact Center end-to-end voice quality testing value clients and agents

Forecasting voice quality using network statistics was sufficient for the days when one could control the network.

Different suppliers, networks, systems, software, hardware influence customer and agent experience. Only network metrics cannot ensure that all entities involved in the voice path work properly and give the best or satisfactory quality of caller experience (QoE).

Using network parameters to calculate MOS for cloud-based contact center and agent connection does not represent possible issues inside the cloud or voice paths connected to it.

Automation of test calls simulating caller and agent activity that will play audio file of “excellent” quality (the so-called reference audio) over the environment and record actual audio received by correspondent endpoints will give objective quality score for the whole voice path if one can compare the reference and test files for quality loss.

Sevana AQuA makes this comparison fast and easy providing reliable MOS score and reports on various quality issues that affected the caller perception. Furthermore, AQuA will pinpoint timestamps of the conversation where the problems occurred and indicate the type of impairment, which will help to identify the “faulty” part of the voice path.

This approach is useful at any stage of deployment – evaluation, piloting, transition, or production. If on demand, or scheduled voice quality scoring is not enough one can use Sevana PVQA for real-time voice quality analysis, problems alerting and reporting within the same feature of indicating impairments that affected the quality loss, but in real time.

Waveform analysis is the approach that gives objective overview on voice quality in cloud contact centers. Sevana tools perform perfectly well for voice quality measurement and analysis in the cloud.

Do you want to know about call quality issues prior your customers start complaining?

Sevana libraries collect all the QoS and QoE data of the calls in real-time, providing immediate alerting on changes that affect callers’ perception, discover and store reasons for call audio degradation.

Map audio impairments on network metrics and discover QoE and QoS patterns, specific to certain routes, destinations, originations, or parts of the traffic. Every call, analyzed by the system, creates big data that one can study, using data analysis tools, to predict network behavior and call quality.


Sevana PVQA – Passive Voice Quality Analyzer is the tool that will help you with this task.
It is a unique powerful tool to non-intrusively (without comparing with reference audio file) evaluate voice quality by waveform analysis. PVQA MOS is perhaps the most accurate compared to other tools that predict MOS score by single file waveform analysis. Tool performance and ability to work in real-time give companies an opportunity to develop their own voice quality testing solutions not being dependent on particular hardware and software. PVQA is available as a cross platform application or library for all main desktop and mobile operating systems. Keep an eye on call quality with sevana.biz

AQuA perfectly suits IVR systems testing when one has a reference audio (original quality IVR prompt) to compare with the recorded audio. But how to validate IVR prompt quality if there is no reference to compare with? However, there is a possibility to validate IVR prompt quality even without comparison by using Sevana PVQA. It is just the same way as one analyzes voice quality of call recordings, because PVQA can forecast a quality score by waveform analysis of a single audio file. Contact us to learn more!