samailsworthartsandcrafts

[samailsworthartsandcrafts]

Final Blog Post

For my final project, my goal was to create a drum pad, (similar to the rubber-topped commercially available ones) with potentiometers controlling reverb/delay and with an analog baby-10 sequencer housed underneath it. I realized that I did not have enough time to complete this entire instrument, so I had to choose the sample player or the sequencer. I figured the sample player would be somewhat easier to troubleshoot so I went with that.

 I started by drawing out the layout for the instrument, which I was sure I had thought through completely, and all I had to do would be to solder a few wires and put the thing together. This was not the case. I started with contact microphones as the drum triggers. I glued them onto CDs which were placed between a block of foam and a square of corkboard. After the original tests with the contact mics, I thought they would work once I got them in a stationary place. The outputs were pretty sporadic and random, but occasionally they would go up when they were supposed to. A lot of the time, the trends of the numbers would switch i.e. when the pad was struck, the numbers would decrease to 0 instead of going up to 1023. A couple of the pads also had issues where they would be sitting with no stimulus and would slowly rise up to 1023 and get stuck. Other times the pads would just get stuck at a high number and constantly trigger the sample without me triggering it. I think all of these issues may have been caused by bad wiring/soldering or a faulty setup with how I placed the contact mics on the pads themselves, but the inconsistency was exhausting.

I could not play the instrument the way I had planned on playing it since the pads were not very reactive to drum sticks and were randomly triggered so often. In my performance of this preliminary version of the instrument, I did not have all of the pads working and I had no idea how the contact mics would act on that day especially since it was raining on the way over to class :( . The only way I knew I could get somewhat consistent sound out of the instrument was to use my hands to apply pressure to the pad-tops to create general trends in the voltages. I realized that this would not work very well with short percussive sounds, but if I loaded longer, more ambient sounds and applied a long reverb, the instrument could become a cool ambient instrument. The performance went well enough that the main idea of my instrument could be conveyed, but I was still frustrated with how unpredictable the instrument was. 

I started to google FSR sensors, and I asked Peter if they would be better to use for a pad controller and he said that most commercial pad controllers have shifted to those types of sensors. He ended up finding 4 of them for me to use to replace the contact microphones. After some fooling around with the teensy and Max, the FSRs worked! They worked well too! When I pressed on them, they gave consistent feedback, and it seemed like my drum controller was going to happen!

I came into the maker’s space to recreate my instrument as an FSR-triggered instrument in the next few days. I decided to snip the wires connected to the contact mics and just place another layer of cork over each pad. I had three small FSRs and one large FSR. After trying all of them out in Max, I was excited because they were all working pretty similarly. I had to test a bunch of different resistors to create the best response from the sensors, but I finally found a good mix of resistors set up in parallel with the FSRs. I glued my first one to the bottom cork layer and then glued the 4 corners of another square of cork to put on top, but it seemed like I had to hit the pad way too hard to get any reasonable amount of sound. I found this disconcerting, but after thinking about it, I realized that when I hit the cork board, the force was distributed to the four corners where I had hot glued it the the lower cork board. I then ripped it off, and put one big blob of hot glue right in the middle where the FSR was, and pressed it back down. The integer on Max shot up to 1023 and stayed there. No matter what I did, it wouldn’t budge. I then had to rip off the cork board again and perform surgery on the FSR. It seemed that I had heated it up too much and the two sides of it had melted together. I used flush-cutters to pull apart the sides of the sensor and I was about to give up and only have three pads, but after about 15 minutes, the sensor came back to life and dropped back down to its default voltage. I now knew that I couldn’t hot glue the tops of these to the cork pad. 

It was at this point that I realized that a large-scale drum trigger with tiny FSRs was most likely not going to happen. This was a bit of a bummer, but I figured at least these sensors would be better than contact mics for an ambient instrument. I went ahead and glued on all of the FSRs and cork pads on top and it seemed more responsive than the contact mic instrument. The one big pad actually worked decently as a drum trigger. Everything was going well. The only problem I had left was the retriggering of the samples. I think that since this was such an elementary problem, it wasn’t addressed in depth on any forums online, but somewhere I read that onebang was the object I needed to use to keep this retriggering from happening. I also felt like I had remembered Peter saying something about onebang to a few of us before. I looked at the inputs/outputs of onebang and sfplay and finally figured it out! It would wait until the sample stopped playing to trigger it again! I finally felt like I had an instrument that was ready to perform.

The FSRs worked wonderfully with this as an ambient instrument. The foam gave it a nice resistance to the pressure of my touch. After playing around with the instrument and thinking about it, I wished I had a different layout that wasn’t so industrial-looking. I wished I had made the form of the instrument match the style of playing it and the sounds that it was best at creating. I could have made it more fun to look at and spent more time on the aesthetic if I started my final project knowing that it would be an instrument for ambient sounds. 

I think I will continue to alter this instrument and make it into not only a playable instrument, but also a performable instrument that looks good and makes sense. I would still like to put a sequencer in the same body as this sample player, but i think I would like to put it all in a completely different body than what I originally had thought.

- Thanks Peter for an awesome semester. This has been by far my favorite class at UVA and I will definitely continue to use and expand on the things I learned in this class for a long time. 

[samailsworthartsandcrafts]

PENULTIMATE POST

My final project ended up being quite different from how I had planned. Originally I had planned to create a multi-instrument with an analog sequencer and a drum pad all in one enclosure. I realized I only had time to do the drum pad, so I started with contact mics, teensy, foam, and cork. My max patch was retriggered a lot with the contact mics, and I did not know how to use onebang yet, but the voltages from the contact mics were too random for them to be a viable tool for a drum pad. The image below is of the circuit when using the contact mics. 1Mohm resistors were placed in parallel with the contact mics to tailor the voltage to a usable value for the teensy. 

[samailsworthartsandcrafts]

11/14 Blog Post

We started using the teensy today, and we got an LED to be controlled by the computer. I have used arduino before with servo motors, but I have never used microcontrollers for audio purposes so I am excited. I think for my next project I want to make a sample player possibly using pressure pads or contact mics. For my final project, I am thinking of making a combo electronic instrument to be performed. I would like to have an analog sequencer (such as the baby8 or baby10) built into a container that could also house sample pads that could be played with drum sticks or maybe hands. If I could somehow route these two things through onboard effects such as reverb, that could be cool as well but probably would make the instrument incredibly difficult to build.

[samailsworthartsandcrafts]

11/7 Blog Post

Today we performed our synthesizers! Mine worked well but there were some sounds I was hoping to get that I couldn’t quite find quickly while exploring the possibilities today. The extra capacitor in the circuit made the distinct attack sound of the instrument but something with the wiring or the amp in the circuit made the sounds in general somewhat unpredictable. The volume knob works backwards when playing out of the built in speaker as compared to running the sound out of the output jack. I prefer the sound from the output jack now. I ran the synth through some reverb and delay using ableton live last night but decided against using those effects for my performance today because they would detract from how interesting the sounds of the synthesizer can be by itself. The final product was not enclosed because after about 45 minutes of trying to squish everything into the tuppeware box, I got tired of resoldering parts that came unsoldered so I decided that an easy access to the battery was not too terrible of a set up. I would like to make another synthesizer soon. I hope I can find the time to make a sequencer - maybe as a final project. I hope to also put effects in the unit itself such as reverb or delay. The effects may even be more of an undertaking than the synth itself but I will have to do more research. 

I will post a video of my hex-schmitt synth this week at some point

[samailsworthartsandcrafts]

10/31 Blog post

Today I have finished the circuit of my synthesizer. I have brought in a tuppeware container for housing the instrument, but since I have not started soldering to the protoboard, I am not sure exactly what the set up will be of potentiometers and such. My hex-schmitt synth sounds completely differently when I use a 1/4″ jack to plug it into the speakers in the maker studio instead of running it through the amplifier and the small speaker. With the classroom speakers there are more distinct voices and less periodic pulses of sounds, but by replacing resistors with diodes, the synth has great character. With the built in amp and speaker, the voices have different volumes and blend into one sound with distinct pulsing. The sound is grittier and less predictable with this method, but I am kind of favoring the built in amp sound rather than the perfect output jack sound. I think I may put in a switch so I can choose between the two since they are such different sounds. The volume knob also changes the character of the sound, it almost acts as a release envelope controller at lower volumes.

[samailsworthartsandcrafts]

10/24 Blog Post

I did not get any pictures for my blog post this week, but here is an update on the synthesizer project:

I have gotten the synthesizer and the amplifier working with some cool square waves coming out of the speaker. I have gotten two separate voices to work, and today when I tried to do two separate voices again with potentiometers, I got one potentiometer modulating the frequency of the pulses of the other potentiometer. So one controlled pitch and the other controlled the speed of the pulses. I have a linear variable resistor hooked up for volume control but it is not working very well. The effect of the pulses came accidentally, and I will have to look up in the textbook how it should be done, but I really like where the sound is going now. I would like to integrate a low pass filter into the circuit, but after looking at the schematics for it, I think I will need to get another IC for that. I think in the end I want to have at least one voice in which a filter is controlled, the speed of the pulses is controlled, and the pitch is controlled by separate potentiometers. 

[samailsworthartsandcrafts]

10/17 blog post

Today we started the Hex Schmitt synthesizers. I am really looking forward to this project. They already sound really awesome with only one or two voices. In my physics classes, we learned about capacitors and resistors but it’s a lot cooler to actually get hands on experience with them and to make sounds with them. I think for my synthesizer project I want to build one with tunable voices and a sequencer hopefully with speed control. I screwed around in high school with components trying to make guitar pedals and hopefully a synthesizer but I didn’t have any direction so I didn’t know which IC’s to get, so this is a really exciting project for me. I can’t wait to run these synths through some effects.

[samailsworthartsandcrafts]

Today we finally performed our instruments. At first I was surprised to hear a new buzzing noise coming from my amplifier, but it was only because it was plugged in while I was using it and unplugging it solved the issue. Yesterday I came in and put a back on the amplifier and figured out how I would mic up my instrument. I decided the top of the pole was the best place. Under the pedal works as well, but in order to get the cool spring sounds as well as the guitar string sounds, the top of the pole was the best option. It was interesting to see that Susan had the exact same mic placement for a similar instrument. I loved all the performances today, I was very impressed. I especially enjoyed the performances that were most planned out. I am glad we all jammed together at the end. It was pretty hectic, but it was a one of a kind moment with everyone playing on instruments and amps they made.

[samailsworthartsandcrafts]

I am essentially done with my amplifier. I will still need to come in this weekend to the maker’s studio to finish hot gluing parts to the chassis, and to create a back for the amplifier. The volume knob is a little loose so I will need to hot glue it in place. I will need too erase the pencil marks on the front panel. On my instrument I still need to adhere a contact microphone. I have tested the amplifier and all is working. A setback last week was when one of the traces was ripped off and I had to start a new amplifier today, but I made good progress and am close to finishing.

[samailsworthartsandcrafts]

9/27

I apologize for forgetting to do these on Tuesday evenings. 

As of now I am essentially done planning my sound system. The only big choices I really have left are whether to put a power switch or not and where to put it. A big step forward was getting the physical speaker in the enclosure. It looks great and all my measurements worked! I will be spending a lot of time soldering and de-soldering in the next few classes to get the amp up to speed and playable. I went ahead and fixated my side panel onto the enclosure and drilled two holes: one for the input jack and one for the power input. I have decided to keep things simple for this project and just do a mono speaker with one input, but I am used to that because of playing through guitar amps. I think I am on a good track to finish the sound system on time.

[samailsworthartsandcrafts]

Speaker and side panel

[samailsworthartsandcrafts]

Amplifier and plate where input will go

[samailsworthartsandcrafts]

9/19 Blog post

This week I am getting a final layout of what my amplifier will look like. Originally I though I would put the switch on the top of the box and the inputs on top as well. After seeing the length of the pieces, I decided that was not an option because the wood is too thick. I thought I could get the inputs to work in a crevasse in the side of the box, but it was still too thick. I ended up having to use the hole saw to make two holes to put the power supply and the input in a thinner wood so it could fit. I will end up putting the other switches on the front where there is also thinner wood. 

I have started to solder the amplifier (or desolder to be exact). I have taken the volume potentiometer off to be able to place it wherever I would like. I have soldered my input jack to two wires as well. On Thursday I will most likely spend more time on the soldering aspects.

[samailsworthartsandcrafts]

after gluing the faceplate and drilling the sound holes

[samailsworthartsandcrafts]

Blog Post 2

The instrument is essentially done other than putting a contact mic on it in some way. It sounds pretty nice even without being plugged in. I have decided to use “tuning pegs” since it was very hard to get a similar tension on all three strings simultaneously. They work decently. The spring gives it a nice natural reverb and could act as its own sound-creating device. I am not going to make the pole which holds the strings a permanent fixture since it is nice to be able to fold it up for storage. The drawer is starting to seem like a good idea for an amplifier. I like the extra wood I brought in, and I think it is shaped well so it will sound great. I have the design laid out and I have started to make the face-plate of the amplifier to let out sound through the wood. The speaker will be housed inside the amplifier, but I think the pattern I am drilling will let out enough sound that it will sound good. I used the jigsaw to cut the face.

[samailsworthartsandcrafts]

The first is a diagram of the amp ideas, the second: the instrument

[samailsworthartsandcrafts]

9/5 Blog post

I am very excited about creating my instrument and amplifier/speaker in class. For my speaker, I brought in a drawer from an old cabinet. The back is a little flimsy and there is an open side, so I brought in a sheet of hardwood to cover up those sides. I have not completely decided yet, but I will either put the speaker on the big, flat side with inputs and knobs on the top or I will put one small speaker on each narrow side with inputs and knobs on top for more of a stereo effect. For my instrument I was inspired by the instrument in the maker studio with the pvc pipe and guitar strings, and I was also inspired by the idea of a pedal steel guitar. So far I have a vertical rod with a guitar string tied to it and the other end connected to a pedal on the floor that can be used to tighten the string and raise the pitch when it’s struck. I think I may add two more strings to the instrument to create different pitches. These pictures I’m including are my diagrams of my ideas for the speaker and the instrument.