Post 6: Doing the experiment 1 (part2)

Time 10:00- 18:00
Date: 16 May 2009
Place: Home

To stimulate the suggested performance as well as the ON/OFF effect I have composed three different musical fractions of 2,4 and 8 bars. After that I created a long audio file with the effect of ON/OFF (music-silence-music-silence e.t.c). I have also created audio files with the opposite effect OFF/ON. These file are around 8 minutes long. Then, I have imported the music files into two different iPots that were connected as an input source for the two locations/laptops A and B. The music composition and the creation of the two audio files were produced with Logic Pro.

The main outcome from this experiment is:
1. To find out whether latency can be added between two places when the performers play the same tempo with no time variations.
2. To investigate more how audio network works in relation with latency
3. To explore existing software’s that uses audio network and therefore latency

The experiment.


Laptop A plays the 2 bar music fragment, so 4 seconds of music at 120 bpm, through the internet using the eJamming Audio 2.0 software. The software interface has various modes that deal with the quality of sound and the latency.


In the upper right there is the section that allows the changes of latency and audio quality streaming. Before going any further it is wise to give a short explanation about the functions that are in the software. There are three modes Jam, Sync and VRS that deal with latency in a different way.

In Jam mode you cannot record but you adjust latency, from auto to manual to distance. Auto, automatically translate the average ms between the two locations in order t have a reasonable audio with no dropouts. Manual is the manual adjustment of the latency. Distance, refers to the predetermine tempo in millisecond so that it sounds one beat behind. For example in tempo 120 the 500ms refer to one-quarter beat. The Sync mode does not allow any latency since is mostly used for recording sessions. The VRS, virtual recording studio allow changes in latency but you can only record one track at any time.


In the suggested performance one of the two performers starts by the time that hears sound from the other location. It was also mentioned that when A in ON B is OFF. However, thie following video attempt did not follow that plan.
This was done because the experiment was aiming to find out whether latency could be added in order to allow the phasing effect. The software used here, as mentioned above has the options to adjust latency. As you can see from the video nothing happened in terms of adding the latency. This is because the software in sync mode is not allowing any latency interference and since the two laptops where less then a meter apart there was no noticeable latency. As you can see from the video nothing changes when I mess around with different latencies (look at the upper right at 1:07 min).



I have also try another way to find out whether latency can be added in order to create the phasing effect. A and B start at the same time, meaning that the play button was pressed simultaneously since both laptops are in the same location, my house. Since I was not able to record through the eJamming the quality of the sound is not good. In order to record I have use another laptop with the following specifications.

Hardware:

Model name: PowerBook G4 12”
Processor Name: PowerPC G4(1.5)
Processor Speed: 1.5 GHz
Memory: 1.25 GB
Mac OS: 10.5.5

Software:
Audacity 1.3.7

This had some positive and negative results. The positive result is the possibility to have the phasing effect. The negative is that when, during playing, there is a change in the amount of latency, clicks and scratches are noticeable. The following video is the playback sound file from location A that was transformed into a video to be able to upload it in the blog.