Howto:Creating fine announcements and music on hold
Applies To
This information applies to
innovaphone PBX
More Information
The innovaphone PBX allows playing audio files in Waiting Queues, Music on Hold and trough XML commands and so a bunch of “audio-scenarios” are possible; from simple once like customized MOH up to complex setups like small IVR’s. But often the sound quality is very poor when you call: music on hold with ugly sound, self-made IVR with nearly incomprensive messages does not really give “additional value” to your customer or improve the image. A pity because you are in front of a marvelous system which is able to do work perfect if the input is done well. So if you have “experience” with embarrassing voice prompts or worst music reproduction maybe it could help reading this article. If you just plan to offer audio services to your customer; read it too. If you are not sure about audio: read it! Remember that if the impression for a caller is disastrous the result will be de-marketing for your customer. So it could be better use tones and standard MOH.
One fundamental point is having good audio source files for all “audio services”. The best result is achieved using a professional speaker in a recording studio. If you have this type of quality in mind for your solution we are very happy, contact a recording studio and the result for the source will be perfect. But many customers want play a “house made” audio file, a quick and in most cases simple solution without any complication and delays trading with recording studios and stuff like that. Audio is available on each PC and so click and go solutions are frequently used. This article gives you some hints what to observe in producing reasonable good sounding “handmade” audio files. So here is how to simulate a professional appearance.
Important
innovaphone is operating in the switching market and is not an “audio company”. This article tries just to help people who have even minor experience then us in creating audio files for telephony use (definitely a lot of people …). So do not expect from us the ultimate audio hint, anyway internet is full of that stuff. And if you are a PC freak some statements and tips are obsolete and you can and should use your own professional or alternative tools.
All the software, free- and shareware we mentioned in this article is just to inform you: not to invite you to use it, we do not recommend any application. Inform yourself also always about the copyrights and relatives items. Remember that music is a “protected good” and you have to observe authors rights and generally the relative regulations in your country. In some countries playing any music on a “public” trunk line means also the obligation to pay charges. Note that even all the samples you find here are just samples for training purpose and not for production use. All trademarks and companies named in this article are used just as example. Innovaphone will not respond of them nor of the usage of those products.
Problem Details
The production of your audio application in an innovaphone PBX can be spitted in the following steps:
- one Creating the audio file
- two Normalization of the audio source
- three Compiling the audio source in the telephone formats
- four Copy of the telephone format files in the destination directory
- five Setup in your innovaphone PBX.
This last step will not be described in this article; you will find a lot of articles about that in this wiki, just follow the links at the end of this article.
1. Creating the audio file
Voice files
The simplest way to produce telephony voice prompts is to use the telephone set, for example using this xml: Howto:Simple Message Management In this sample the recording is done using a telephone set, nice for self made prompts, but you will always hear that the recording is done using a phone set. No editing using standard software is possible. Another way to producing Voice Prompts is using text-to-speech software (TTS). For example Acapela has a nice interface and product; you can try a demo on http://www.acapela-group.com/text-to-speech-interactive-demo.html The disadvantage using computer generated prompts is that you hear immediately the “computer voice”. On the other hand it is much better than many self-made registrations. So we can say that it is not an optimal solution but you have at least “constantly quality” which is better in many cases. TTS solves also the problem if you don’t have a native speaker. Better results are possible recording the announcement with a microphone directly on your PC (that is also the option people like). You can do this using an application or just the audio recorder tool in the folder accessories of your XP or Vista/Win7 operating system. Using Laptop build in microphones is not recommended, better are external microphones. The cheapest are the build in one in the headset for gamer. The advantage of those headsets with microphone is that you can use them also for the sound check, you will hear more details with a headset then using external speaker. The headsets for softphones will also work fine. If you record the prompts with a microphone, observe the following hints:
- Female speaker are better than male because generally female voices have better sound quality ad are more understandable on bad connections.
- Write down the text for the speaker and print it out. Do that even if the sentence is apparently simple and short.
- If you have more prompts try to record them all in one single session. In the next session, after an hour or day the voice will change and your setup will never be the same. If it is not possible recording all prompts in one single session and you have to record an announcement in a second time try at least to reproduce the setup (distance of the microphone from the mouth, mixer setup and similar). You will hear anyway small differences, not nice if you compose a sentence with single prompts or reproduce one message after another, a minor problem if just one new text is prompted.
- Even if you have to produce single prompts it is better record all of them in one session (or at least a bunch of them) and then creates single prompts in the post production.
- Drink a gulp of water before recording. Lips become so moist and you have less “pop” at the beginning of a word.
- Record all two or more times, at the end select the best version.
- Record in the best quality you can, usually the recorder as default will yet have such a setup (typically 44khz, 16 bit stereo), don’t worry at this step about the telephony limitations. After recording in stereo build a mono version maintaining the high sample rate and start postproduction with this file. With a good source file you will better recognize small imperfections and can correct them easily.
Now follows the most important step for voice prompts: post-production. The raw audio file will have a lot of imperfections (no studio, no professional speaker and no professional equipment) which will be hearable even on the phone. But we can correct most of them: Pop: when a speaker starts talking the opening of the lips causes a “pop” and this will be recorded perfectly from a microphone. To limit this effect the speaker should drink water before talking. Have you seen some picture or video of recording studios where people is singing and there is a strange round filter like a disk in front of the microphone?
