Second session at Norwegian Academy of Music (Oslo) – January 13. and 19., 2017

Participants: Bjørnar Habbestad (flute), Bernt Isak Wærstad (guitar), Gyrid Nordal Kaldestad (voice)

The focus for this session was to play with, fine tune and work further on the mappings we sat up during the last session at NMH in November. Due to practical reasons, we had to split the session into two half days on 13th and 19th of January

13th of January 2017

We started by analysing 4 different musical gestures for the guitar, which was skipped due to time constraints during the last session. During this analysis we found the need to specify the spread of the analysis results in addition to the region. This way we could differentiate the analysis results in terms of stability and conclusiveness. We decided to analyse the flute and vocal again to add the new parameters.

19th of January 2017

After the analysis was done, we started working on a mapping scheme which involved all 3 instruments, so that we could play in a trio setup. The mappings between flute and vocal where the same as in the November session

The analyser was still run in Reaper, but all routing, effects chain and mapping (MIDIator) was now done in Live. Because of software instability (the old Reaper projects from November wouldn’t open) and change of DAW from Reaper to Live, meant that we had to set up and tune everything from scratch.

Sound examples with comments and immediate reflections

1. Guitar & Vocal – First duo test, not ideal, forgot to mute analyser.

2. Guitar & Vocal retake – Listened back on speakers after recording. Nice sounding. Promising.

Reflection: There seems to be some elements missing, in a good way, meaning that there is space left for things to happen in the trio format. There is still need for fine-tuning of the relationship between guitar and vocal. This scenario stems from the mapping being done mainly with the trio format in mind.

3. Vocals & flute – Listened back on speakers after recording.

Reflections: dynamic soundscape, quite diverse results, some of the same situations as with take 2, the sounds feel complementary to something else. Effect tuning: more subtle ring mod (good!) compared to last session, the filter on vocals is a bit too heavy-handed. Should we flip the vocal filter? This could prevent filtering and reverb taking place simultaneously. Concern: is the guitar/vocal relationship weaker compared to vocal/flute? Another idea comes up – should we look at connecting gates or bypasses in order to create dynamic transitions between dry and processed signals?

4.Flute & Guitar

Reflections: both the flute ring mod and git delay are a bit on the heavy side, not responsive enough. Interesting how the effect transformations affect material choices when improvising.

5.Trio

Comments and reflections after the recording session

It is interesting to be in a situation where you, as you play, are having multi-layered focuses- playing, listening, thinking of how you affect the processing of your fellow musicians and how your sound is affected and trying to make something worth listening to. Of course we are now in an “etyde- mode”, but still striving for the goal, great output!

It seems to be a bug in the analyser tool when it comes to being consistent. Sometimes some parameters fall out. We experienced that it seems to be a good idea to run the analyse a couple of times for each sound to get the most precise result.

Cross adaptive session with 1st year jazz students, NTNU, March 7-8

This is a description of a session with first year jazz students at NTNU recorded March 7 and 8. The session was organized as part of the ensemble teaching that is given to jazz students at NTNU, and was meant to take care of both the learning outcomes from the normal ensemble teaching, and also aspects related to the cross adaptive project.

Musicians:

Håvard Aufles, Thea Ellingsen Grant, Erlend Vangen Kongstorp, Rino Sivathas, Øyvind Frøberg Mathisen, Jonas Enroth, Phillip Edwards Granly, Malin Dahl Ødegård and Mona Thu Ho Krogstad.

Processing musician:

Trond Engum

Video documentation:

Andreas Bergsland

Sound technician:
Thomas Henriksen

 

Video digest from the session:

Preparation:

Based on our earlier experiences with bleeding between microphones we located instruments in separate rooms. Since there was quit a big group of different performers it was important that changing set-up took as little time as possible. There was also prepared a system set-up beforehand based on the instruments in use. To gain an understanding of the project from the performer side as early in the process as possible we used the same four step chronology when introducing the performers to the set-up.

  1. Start with individual instruments trying different effects through live processing and decide together with the performers what effects most suitable to add to their instrument.
  2. Introducing the analyser and decide, based on input form the performers, which methods best suited for controlling different effects from their instrument.
  3. Introducing adaptive processing were one performer is controlling the effects on the other, and then repeat vice versa.
  4. Introducing cross-adaptive processing were all previous choices and mappings are opened up for both performers.

 

Session report:

Day 1. Tuesday 7th March

Trumpet and drums

Sound example 1: (Step 1) Trumpet live processed with two different effects, convolution (impulse response from water) and overdrive.

 

The performer was satisfied with the chosen effects, also because the two were quite different in sound quality. The overdrive was experienced as nice, but he would not like to have it present all the time. We decided to save these effects for later use on trumpet, and be aware of dynamic control on the overdrive.

 

Sound example 2: (Step 1) Drums live processed with dynamically changing delay and a pitch shift 2 octaves down. The performer found the chosen effects interesting, and the mapping was saved for later use.

 

Sound example 3: (Step 1) Before entering the analyser and adaptive processing we wanted to try playing together with the effects we had chosen to see if they blended well together. The trumpet player had some problems with hearing the drums during the performance, felt as they were a bit in the background. We found out that the direct sound of the drums was a bit low in the mix, and this was adjusted. We discussed that it is possible to make the direct sound of both instruments louder or softer depending what the performer wants to achieve.

 

Sound example 4. (Step 2/3) For this example we entered into the analyser using transient density on drums. This was tried out by showing the analyser at the same time as doing an accelerando on drums. This was then set up as an adaptive control from drums on the trumpet. For control, the trumpet player had a suggestion that the more transient density the less convolution effect was added to the trumpet (less send to a convolution effect with a recording of water). The reason for this was that it could make more sense to have more water on slow ambient parts than on the faster hectic parts. At the same time he suggested that the opposite should happen when adding overdrive to the trumpet by transient density meaning that the more transient density the more overdrive on the trumpet. During the first take a reverb was added to the overdrive in order to blend the sound more into the production. It felt like the dynamical control over the effects was a bit difficult because the water disappeared to easily, and the overdrive was introduced to easily. We agreed to fine-tune the dynamical control before doing the actual test that is present as sound example 4.

 

Sound example 5: For this example we changed roles and enabled the trumpet to control the drums (adaptive processing). We followed a suggestion from the trumpet player and used pitch as an analyses parameter. We decided to use this to control the delay effect on the drums. Low notes produced long gaps between delays, whereas high notes produced small gap between delays. This was maybe not the best solution for getting good dynamical control, but we decide to keep this anyway.

 

Sound example 6: Cross adaptive performance using the effects and control mappings introduced in example 4 and 5. This was a nice experience for the musicians. Even though it still felt a bit difficult to control it was experienced as musical meaningful. Drummer: “Nice to play a steady grove, and listen to how the trumpet changed the sound of my instrument”.

 

Vocals and piano

Sound example 7: We had now changed the instrumentation over to vocals and piano, and we started with a performance doing live processing on both instruments. The vocals were processed using two different effects using a delay, and convolution through a recording of small metal parts. The piano was processed using an overdrive and convolution through water.

 

Sound example 8: Cross adaptive performance where the piano was analysed by rhythmical consonance controlling the delay effect on vocals. The vocal was analysed by transient density controlling the convolution effect on the piano. Both musicians found this difficult, but musically meaningful. Sometimes the control aspect was experienced as counterintuitive to the musical intention. Pianist: It felt like there was a 3rd musician present.

 

Saxophone self-adaptive processing

Sound example 9: We started with a performance doing live processing to familiarize the performer with the effects. The performer found the augmentation of extended techniques as clicks and pops interesting since this magnified “small” sounds.

 

Sound example 10: Self-adaptive processing performances where the saxophone was analysed by transient density and then used to control two different convolution effects (recording of metal parts and recording of a cymbal). The first one resulting in a delay effect the second as a reverb. The higher transient density in the analyses the more delay and less reverb and vice versa. The performer experienced the quality of the effects quit similar so we removed the delay effect.

 

Sound example 11: Self-adaptive processing performances using the same set-up but changing the delay effect to overdrive. The use of overdrive on saxophone did not bring anything new to the table the way it was set up since the acoustic sound of the instrument could sound similar to the effect when putting in strong energy.

 

Day 2. Wednesday 8th March

 

Saxophone and piano

Sound example 12: Performance with saxophone and live processing, familiarizing the performer with the different effects and then choose which of the effects to bring further into the session. Performer found this interesting and wanted to continue with reverb ideas.

 

Sound example 13: Performance with piano and live processing. The performer especially liked the last part with the delays – Saxophonist: “It was like listening to the sound under water (convolution with water) sometimes, and sometimes like listening to an old radio (overdrive)”. Piano wanted to keep the effects that were introduced.

 

Sound example 14: Adaptive processing, controlling delay on saxophone from the piano by using analyses of the transient density. The higher transient density, the larger gap between delays on the saxophone. The saxophone player found it difficult to interact since the piano had a clean sound during performance. The piano on the other hand felt in control over the effect that was added.

 

Sound example 15: Adaptive processing using saxophone to control piano. We analyzed the rhythmical consonance on saxophone. The higher degree of consonance, the more convolution effect (water) was added to piano and vice versa. Saxophone didn’t feel in control during performance, and guessed it was due to not holding a steady rhythm over a longer period. The direct sound of the piano was also a bit loud in the mix making the added effect a bit low in the mix. Piano felt that saxophone was in control, but agreed to the point that the analyses was not able to read to the limit because of the lack of a steady rhythm over a longer time period.

 

Sound example 16: Crossadptive performance using the same set-up as in example 14 and 15. Both performers felt in control, and started to explore more of the possibilities. Interesting point when the saxophone stops to play since the rhythmical consonance analyses will make a drop as soon as it starts to read again. This could result in strong musical statements.

 

Sound example 17: Crossadaptive performance keeping the same setting but adding rms analyses on the saxophone to control a delay on the piano (the higher rms the less delay and vice versa).

 

Vocals and electric guitar

Sound example 18: Performance with vocals and live processing. Vocalist: “It is fun, but something you need to get use to, needs a lot of time”.

 

Sound example 19: Performance with Guitar and live processing. Guitarist: “Adapted to the effects, my direct sound probably sounds terrible, feel that I`m loosing my touch, but feels complementary and a nice experience”.

 

Sound example 20: Performance with adaptive processing. Analyzing the guitar using rms and transient density. The higher transient density the more delay added to the vocal, and higher rms the less reverb added to the vocal. Guitar: I feel like a remote controller and it is hard to focus on what I play sometimes. Vocalist: “Feels like a two dimensional way of playing”.

 

Sound example 21: Performance with adaptive processing. Controlling the guitar by vocals. Analyzing the rhythmical consonance on the vocal to control the time gap between delays inserted on the guitar. Higher rhythmical consonance results in larger gaps and vice versa. The transient density on vocal controls the amount of pitch shift added to the guitar. The higher transient density the less volume is sent to the pitch shift.

 

Sound example 22: Performance with cross adaptive processing using the same settings as in sound example 20 and 21.

Vocalist: “It is another way of making music, I think”. Guitarist: “I feel control and I feel my impact, but musical intention really doesn’t fit with what is happening – which is an interesting parameter. Changing so much with doing so little is cool”.

 

Observation and reflections

The sessions has now come to a point were there is less time used on setting up and figuring out how the functionality in the software works, and more time used on actual testing. This is an important step taking in consideration working with musicians that are introduced to the concept the first time. A good stability in software and separation between microphones makes the workflow much more effective. It still took some time to set up everything the first day due to two system crashes, the first one related to the midiator, the second one related to video streaming.

 

Since preparing the system beforehand there was a lot of reuse both concerning analyzing methods and the choice of effects. Even though there were a lot of reuse on the technical side the performances and results has a large variety in expressions. Even though this is not surprising we think it is an important aspect to be reminded of during the project.

 

Another technical workaround that was discussed concerning the analyzing stage was the possibility to operate with two different microphones on the same instrument. The idea is then to use one for reading analyses, and one for capturing the “total” sound of the instrument for use in processing. This will of course depend on which analyzing parameter in use, but will surely help for a more dynamical reading in some situations both concerning bleeding, but also for closer focus on wanted attributes.

 

The pedagogical approach using the four-step introduction was experienced as fruitful when introducing the concept to musicians for the first time. This helped the understanding during the process and therefor resulted in more fruitful discussions and reflections between the performers during the session. Starting with live processing says something about possibilities and flexible control over different effects early in the process, and gives the performers a possibility to be a part of deciding aesthetics and building a framework before entering the control aspect.

 

Quotes from the the performers:

Guitarist: “Totally different experience”. “Felt best when I just let go, but that is the hardest part”. “It feels like I’m a midi controller”. “… Hard to focus on what I’m playing”. “Would like to try out more extreme mappings”

Vocalist: “The product is so different because small things can do dramatic changes”. “Musical intention crashes with control”. “It feels like a 2-dimensional way of playing”

Pianoist: “Feels like an extra musician”

 

 

 

Live convolution with Kjell Nordeson

Session at UCSD March 14.

Kjell Nordeson: Drums
Øyvind Brandtsegg: Vocals, Convolver.

Contact mikes

In this session, we explore the use of convolution with contact mikes on the drums to reduce feedback and cross-bleed. There is still some bleed from drums into the vocal mike, and there is some feedback potential caused by the (miked) drumheads resonating with the sound coming from the speaker. We have earlier used professional contact mikes, but found that our particular type did have a particularly low output, so this time we tried simple and cheap piezo elements from Radio shack, directly connected to high impedance inputs on the RME soundcard. This seems to give very high sensitivity and a fair signal to noise ratio. The frequency response is quite narrow and “characteristic” to put it mildly, but for our purposes, it can work quite well. Also, the high frequency loss associated with convolution is less of an issue when the microphones have such an abundance of high frequencies (and little or no low end).

IR update triggering

We have added the option of using a (midi) pedal to trigger IR recording. This allows a more deliberate performative control of the IR update. This was  first used by Kjell, while Øyvind was playing through Kjell’s IR. Later switched roles. Kjell notes that the progression from IR to IR works well, and that we definitely have some interesting interaction potential here. The merging of the sound from the two instruments creates a “tail” of what has been played, and that we continue to respond to that for a while.
When Kjell recorded the IR, he thought it was an extra distraction to have to also need to focus on what to record, and to operate the pedal accordingly. The mental distraction probably is not so much in the actual operation of the pedal, but in the reflection over what would make a good sound to record. It is not yet easy to foresee (hear) what comes out of the convolution process, so understanding how a particular input will work as an IR is a sort of remote and second-degree guesswork. This is of course also further complicated by not knowing what the other performer will play through the recorded IR. This will obviously become better with more experience using the techniques.
When we switched roles (vocal recording the IR), the acoustic/technical situation became a bit more difficult. The contact mikes, would pick up enough sound from the speakers (also through freely resonating cymbals resting on the drums, and via non-damped drum heads) to create feedback problems. This also creates extra repetitions of the temporal pattern of the IR due to the feedback potential. It was harder to get the sound completely dry and distinct, so the available timbral dynamic was more in the range from “mushy” to “more mushy” (…). Still, Kjell felt this was “more like playing together with another musician”. The feeling of playing through the IR is indeed the more performatively responsive situation, overpowered by the reduction in clarity that was caused by the technical/acustical difficulties. Similarly, Øyvind thought it was harder because the vocals only manifest themself as the ever changing IR, and the switching if the IR does not necessarily come across as a real/quick/responsive musical interaction. Also, delivering some material for the IR makes the quality of the material and the exact excerpt much more important. It is like giving away some part of what you’ve played, and it must be capable of being transformed out of your own control, so the material might become more transparent to it’s weaknesses. One can’t hide any flaws by stringing the material together in a well-flowing manner, rather the stringing-together is activated by the other musician. Easily, I can recognize this as the situation any musician being live sampled or live processed must feel, so it is a “payback time” revelation for me, having been in the role of processing others for many years.

Automatic IR update

We also tried automatic/periodic IR updates, as that would take the distraction of selecting IR material away, and we could more easily just focus on performing. The automatic updates shows their own set of weaknesses when compared with the manually triggered ones. The automatic update procedure essentually creates a random latency for the temporal patterns created by the convolution. This is because the periodic update is not in any way synchronized to the playing, and the performers do not have a feedback (visually or auditively) on the update pulse. This means the the IR update might happen offbeat or in the middle of a phrase. Kjell suggested further randomizing it as one solution. To this, Øyvind responds that it is already essentially random since the segmentation of input and the implied pulse of the material is unrelated, so it will shift in an unpredictable and always changing manner. Then again, following up on Kjells suggestion and randomizing it further could create a whole other, more statistical approach.  Kjell also remarks that this way of playing it feels more like “an effect”, something added, that does not respond as interactively. It just creates a (echo pattern) tail out of whatever is currently played. He suggested updating the IR at a much lower rate, perhaps once every 10 seconds. We tried a take with this setting too.

Switching who has the trigger pedal

Then, since the automatic updates seems not to work too well, and the mental distracion of selecting IR material seems unwanted, we figured, maybe the musician playing through the IR should be the one triggering the IR recording. This is similar (but exactly opposite) to the previous attempts at manual IR record triggering. Here, the musician playing through the IR is the one deciding the time of IR recording, and as such has some influence over the IR content. Still he can not decide what the other musician is playing at the time of recording, but this type of role distribution could create yet another kind of dynamic in the interplay. Sadly the session was interrupted by practical matters at this point, so the work must continue on a later occation.

Audio

kjellconvol1 kjellconvol1

Take1: Percussion IR, vocal playing through the IR. Recording/update of IR done by manual trigger pedal controlled by the percussionist. Thus it is possible to emphasize precise temporal patterns. The recording is done only with contact mikes on the drums, so there is some “disconnectedness” to the acoustic sound.

 

kjellconvol2 kjellconvol2

Take2: Vocal IR, percussion playing through the IR. Recording/update of the IR done by manual trigger pedal controlled by the singer. As in take 1, the drums sound going into the convolver  is only taken from the piezo pickups. Still, there is a better connectedness to the acoustic drum sound, due to an additional room mike being used (dry).

 

kjellconvol3 kjellconvol3

Take3: Percussion IR, automatic/periodic IR update. IR length is 3 seconds, IR update rate is 0.6 Hz.

 

kjellconvol4 kjellconvol4

Take4: Percussion IR, automatic/periodic IR update. IR length is 2.5 seconds, IR update rate is 0.2 Hz.

Other reflections

IR replacement is often experienced as a sudden musical change. There is no artifacts caused by the technical operation of updating the IR, but the musical result is more often a total change of “room characteristic”. Maybe we should try finding methods of slowly crossfading when updating the IR, keeping some aspects of the old one in a transitory phase. There is also a lot to be gained performatively, by the musician updating the IR having these transitions in mind. Choosing what to play and what to record is an effective way of controlling if the transitions should be sudden or slow.

Session with classical percussion students at NTNU, February 20, 2017

Introduction:

This session was a first attempt in trying out cross-adaptive processing with pre-composed material. Two percussionists, Even Hembre and Arne Kristian Sundby, students at the classical section, were invited to perform a composition written for two tambourines. The musicians had already performed this piece earlier in rehearsals and concerts. As a preparation for the session the musicians were asked to do a sound recording of the composition in order to prepare analysis methods and choice of effects before the session. A performance of the piece in its original form can be seen in this video – “Conversation for two tambourines” by Bobby Lopez performed by Even Hembre and Arne Kristian Sundby (recorded by Even Hembre).

Preparation:

Since both performers had limited experience with live electronics in general we decided to introduce the cross adaptive system gradually during the session. The session started with headphone listening, followed by introducing different sound effects while giving visual feedback to the musicians, and then performing with adaptive processing before finally introducing cross-adaptive processing. As a starting point, we used analysis methods which had already proved effective and intuitive in earlier sessions (RMS, transient density and rhythmical consonance). These methods also made it easier to communicate and discuss the technical process with the musicians during the session. The system was set up to control time based effects such as delays and reverbs, but also typical insert effects like filters and overdrive. The effect control contained both dynamical changes of different effect parameters, but also sample/hold function through the MIDIator. We had also brought a foot pedal so the performers could change the effects on the different parts of the composition during the performance.

Session:

After we had prepared and set up the system we discovered severe latency on the outputs of the system. Input signals seemed to function properly, but what was causing the latency of the output was not discovered. To solve the problem, we made a fresh set-up using the same mentioned analysing methods and effects, and after checking that the latency was gone, the session proceeded. We started with a performance of the composition without any effects, but with the performers using headphones to get familiar with the situation. The direct sound of each tambourine was panned hard left/right in the monitoring system to easier identify the two performers. After an initial discussion it was decided that both tambourines should be located in the same room since the visual communication between the performers was important in this particular piece. The microphones were separated with an acoustic barrier/screen and microphones set to cardio characteristic in order to avoid as much bleeding between the two as possible. During the performance the MIDIator was adjusted to the incoming signals. It became clear that there were some issues with bleeding already at this stage affecting the analyser, but we nevertheless retained the set-up to maintain the focus on the performance aspect. The composition had large variations in dynamics, and also in movement of the instruments. This was seen as a challenge considering the microphones’ static placements and the consequently large differences in input signal. Because of the movement, just small distance variations between instrument and microphone would have great impact in how the analysis methods read the signals. During the set-up, the visual feedback from the screen to the performers was a very welcome contribution regarding the understanding of the set-up. While setting up the MIDIator to control the effects we tried playing through the composition again trying out different effects. Adding effects made a big impact to the performance. It became clear that the performers tried to “block out” the effects while playing in order to not loose track of how the piece was composed. In this case the effects almost created a filter between the performers and the composition resulting in a gap between what they expected and what they got. This could of course be a consequence of the effects that was chosen, but the situation demanded another angle to narrow everything down in order to create a better understanding and connection between the performance and the technology. Since the composition consisted of different parts we made a selection of one of the quieter parts where the musicians could see how their playing affected their analysers, and how this further could be mapped to different effects using the MIDIator. There was still a large amount of overlapping between the instruments into the analyser because of bleeding, so we needed to take a break and rearrange the physical set-up in the room to further clarify the connection between musical input, analyser, MIDIator and effects. Avoiding the microphone bleeding helped both the system and the musicians to clarify how the input reacted to the different effects. Since the performers were interested in how this changed the sound of their instruments we agreed to abandon the composition, and instead testing out different set-ups, both adaptive and crossadaptive.

Sound examples:

1. Trying different effects on tambourine, processing musician controlling all parameters. Tambourine 1 (Even) is convolved with a recording of water and a cymbal. Tambourine 2 (Arne Kristian) is processed with delay, convolved with a recording of small metal parts and a pitch delay.

 

2. Tambourine 1 (Even) is analysed using transient density. The transient density is controlling a delay plug in on tambourine 2 (Arne Kristian)

 

3. Tambourine 2 (Arne Kristian) is analysed by transient density controlling a send from tambourine 1 convolved with cymbal. The higher transient density the less send.

 

4. Keeping the mapping settings from example 2 and 3 but adding rhythmical consonance analyses on Tambourine 2 to control another send level from tambourine 1 convolving it with recording of water. The higher consonance the more send. The transient density analysis on tambourine 1 is in addition mapped to control a send from tambourine 2 convolving it with metal parts. The higher density, the more send.

 

Observations:

Even though we worked with a composed piece it would be a good idea to have a “rehearsal” with the performers beforehand focusing on different directions through processing. This could open up for thoughts around how to do a new and meaningful interpretation of the same composition with the new elements.

 

It was a good idea to record the piece beforehand in order to construct the processing system, but this recording did not have any separation between the instruments either. This resulted in preparing and constructing a system that in theory were unable to be cross adaptive since it both analysed and processed the sum of both instruments leaving much less control to the individual musicians. This aspect, also concerning bleeding between microphones in more controlled environments, challenges a concept of fully controlling a cross adaptive performance. This challenge will probably be further magnified in a concert situation preforming through speakers. The musicians also noted that the separation between microphones was crucial for the understanding of the process, and the possibility to get a feeling of control.

In retrospect, the time-based effects prepared for this session could also be changed since several of them often worked against the intention of the composition, especially the most rhythmical parts. Even noted that: “Sometimes it’s like trying to speak with headphones that play your voice right after you have said the word, and that unable you to continue”.

This particular piece could probably benefit from more subtle changes from the processing. The sum of this made the interaction aspect between the performers and the technology more reduced. This became clearer when we abandoned the composition and concentrated on interaction in a more “free” setting. One way of going further into this particular composition could be to take a mixed music approach, and “recompose” and interpret it again with the processing element as a more included part of the composition process.

In the following and final part of the session, the musicians were allowed to freely improvise while being connected to the processing system. This was experienced as much more fruitful by both performers. The analysis algorithms focusing on rhythmical aspects, namely transient density and rhythmical consonance, were both experienced as meaningful and connected to the performers’ playing. These control parameters were mapped to effects like convolution and delay (cf. explanation of sound examples 1-4). The performers focused on issues of control, the differences between “normal” and inverse mapping, headphones monitoring and microphone bleeding when discussing their experiences of the session (see the video digest below for some highlights).

Video digest from session February 20, 2017

Convolution experiments with Jordan Morton

Jordan Morton is a bassist and singer, she regularly performs using both instruments combined. This provides an opportunity to explore how the liveconvolver can work when both the IR and the live input are generated by the same musician. We did a session at UCSD on February 22nd. Here are some reflections and audio excerpts from that session.

General reflections

As compared with playing with live processing, Jordan felt it was more “up to her” to make sensible use of the convolution instrument. With live processing being controlled by another musician, there is also a creative input from another source. In general, electronic additions to the instrument can sometimes add unexpected but desirable aspects to the performance. With live convolution where she is providing both signals, there is a triple (or quadruple) challenge: She needs to decide what to play on the bass, what to sing, explore how those two signals work together when convolved, and finally make it all work as a combined musical statement. It appears this is all manageable, but she’s not getting much help from the outside. In some ways, working with convolution could be compared to looping and overdubs, except the convolution is not static. One can overlay phrases and segments by recording them as IR’s, while shaping their spectral and temporal contour with the triggering sound (the one being convolved with the IR).
Jordan felt it easier to play bass through the vocal IR than the other way around. She tend to lead with the bass when playing acoustic on bass + vocals. The vocals are more an additional timbre added to complete harmonies etc with the bass providing the ground. Maybe the instrument playing through the IR has the opportunity of more actively shaping the musical outcome, while the IR record source is more a “provider” of an environment for the other to actively explore?
In some ways it can seem easier to manage the roles roles (of IR provider and convolution source) as one person than splitting the incentive among two performers. The roles becomes more separated when they are split between different performers than when one person has both roles and then switches between them. When having both roles, it can be easier to explore the nuances of each role. Possible to test out musical incentives by doing this here and then this there, instead of relying on the other person to immediately understand (for example to *keep* the IR, or to *replace* it *now*).

Technical issues

We explored transient triggered IR recording, but had a significant acoustic bleed from bass into the vocal microphone, which made clean transient trigging a bit difficult. A reliable transient triggered recording would be very convenient, as it would allow the performer to “just play”. We tried using manual triggering, controlled by Oeyvind. This works reliably but involves some guesswork as to what is intended to be recorded. As mentioned earlier (e.g. in the first Olso session), we could wish for a foot pedal trigger or other controller directly operated by the performer. Hey it’s easy to do, let’s just add one for next time.
We also explored continuous IR updates based on a metronome trigger. This allows periodic IR updates, in a seemingly streaming fashion. Jordan asked for an indication of the metronomic tempo for the updates, which is perfectly reasonable and would be a good idea to do (although had not been implemented yet). One distinct difference noted when using periodic IR updates is that the IR is always replaced. Thus, it is not possible to “linger” on an IR and explore the character of some interesting part of it. One could simulate such exploration by continuously re-recording similar sounds, but it might be more fruitful to have the ability to “hold” the IR, preventing updates while exploring one particular IR. This hold trigger could reasonably also be placed on a footswitch or other accessible control for the performer.

Audio excerpts

jordan1 jordan1

Take 1: Vocal IR, recording triggered by transient detection.

 

jordan2 jordan2

Take 2: Vocal IR, manually triggered recording 

 

jordan3 jordan3

Take 3: Vocal IR, periodic automatic trigger of IR recording.

 

jordan4 jordan4

Take 4: Vocal IR, periodic automatic trigger of IR recording (same setup as for take 3)

 

jordan5 jordan5

Take 5: Bass IR, transient triggered recording. Transient triggering worked much cleaner on the bass since there was less signal bleed from voice to bass than vice versa.