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!

Are you into conversational analysis?
Do you have millions of call recordings that you like to range based on audio quality?
Sevana PVQA is the tool that can analyze hours of recorded audio in a couple of minutes.
Request a call with our team to learn more about call recordings quality analysis and other related technologies for audio quality assessment.

Being a multipurpose tool for voice quality analysis PVQA Server can be the core of a quality analysis and monitoring system to detect and investigate QoE and QoS related issues. PVQA Server combines the force of audio waveform analysis using PVQA technology with continuous network monitoring:
🔎Real-time call quality monitoring
🔎Proactive maintenance based on non-intrusive waveform analysis
🔎Monitoring network and media quality simultaneously
🔎Matching network metrics (RTT, jitter, latency, packet loss) with payload metrics (noise, clipping, dead air, echo etc)

Voice quality is the term used to describe the clarity of your voice. It’s more than just the sound of your voice—it also includes things like background noise and interference, which can have an adverse effect on how well your voice is heard. This makes passive voice quality testing and analysis and important part of modern communications.

Sevana AQuA and PVQA libraries collect all the data related to impairments that may affect voice quality in real-time providing immediate alerting and storage of all metrics related to call audio degradation. Audio impairments one can map on network parameters (jitter, packet loss, RTT delay) that will form patterns related to certain routes, destinations, originations. Every call analyzed by the system creates data that one can study using bigdata analysis tools to predict network behavior and call quality.

Silent Call – one leg of the voice call has no speech
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 looks like amplitude clipping, however, it is not present at the moment.
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).
Click – is a single energy spike in the spectrum of the audio, which may happen for different reasons.
DeadAir-01 – is a zero-signal level inside speech, a gap in speech that may be caused by different reasons.
DeadAir-00 – is a constant signal level inside speech and may have positive and negative value.
SNR – this means that noise level present in the call affects human perception and disturbs the caller.

Within impairments analysis one can not only detect impairments that degraded voice quality in real-time, but in case of post call analysis pinpoint actual time period when certain impairment took place (as it is specified on the picture, Poor intervals are marked with the same color the impairment detectors that triggered the problem, e.g. Echo)

Further more, big data analysis of reports generated by PVQA help to identify impairment patterns specific for certain problems in the networks, e.g.

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

Contact us to have full demo on PVQA analysis or PVQA Server functionality.