Wednesday May 28th

The feedback resonator project is on pause right now while I prepare for a local pride event. The next step in that project is probably going to be rewiring the pickup connections, and I might try ordering my first PCB with the help of J, who already made a starter board in kicad with footprints for the pickups and a passive mix section!

The pride event is happening at Levee Park, and I think I found a nice spot for us to set everything up where there are some benches and grass and sun by the water, and some concrete forms and walls surrounding the steps where we might find good reflections. Six channels will be exciter/resonators of some sort, in three wireless groups that can be distributed maybe near the wall surrounding the grassy area.

Four channels will be bluetooth speakers – already a classic staple of this park, to be really authentic I should find someone to carry them around on skateboards… those I think will be the best reflectors, and easy to move around and tuck into corners.

The laptop will produce all 10 channels, loud enough to fill that section of the park with tones, but quiet enough to leave room for a trombone, cello and violin accompaniment. I think we’ll all be unamplified, but the strings might be amplified.

The computer part so far is filtered pulsar long tones based around the first 8 overtones of F and C, but I plan to retune somewhat as I write the ensemble parts. Those rules will be loose, the whole thing I imagine will transition to and from a few different sections, with game rules and simple scores for each section. The long tone section maybe featuring sparse ensemble playing, coordinated around a set of one to three note gestures played together ad hoc… and so on with maybe a swarmy arp section an open air section and a ring-resonance section.

Simple enough rules to be able to enjoy playing, and play for some hours potentially, as long as the batteries hold out.

Monday May 12th

Well, dang. I saw there was a new stable version of cython and decided to upgrade this morning on a lark. I went through some of the usual dependency hell, but giving pip the --no-build-isolation flag, which reuses the current virtualenv instead of creating a throwaway one just for the build saved me from it – I didn’t even know pip was doing this, no wonder builds took so long! It must have been rebuilding the entire system for every dependency? Yeesh.

Surprisingly – and I’m still somewhat skeptical there aren’t hidden problems – it all just works, and I was even able to build against the latest python 3.13.x. I’m not sure if it’s the python upgrade (probably! thanks make cpython faster team) or the cython upgrade (could be!) or the numpy upgrade (hope not! I’m still on track to get rid of it eventually) but the test suite runs now in less than half the time it has for the last couple years. I use the test suite runtime as a back of the napkin guide to see if I’m making performance better or worse, so that’s very cool and encouraging! Went from about 60 seconds to run a hundred or so tests, down to around 20!

I decided this weekend that I need to reconfigure the astrid process callback situation somewhat. Jack has lock free realtime-safe ring buffers and it’s becoming clear I’m never going to be able to use IPC directly inside the realtime callback – because it locks! Maybe one day astrid will have lock-free IPC (hope so!) but that’s a project for a future me. Instead, I’m going to move all the processing into a dedicated thread, and just push samples into and out of it via the jack ring buffers. This has the nice side effect of making astrid ever so slightly more portable, for future iterations with different sound driver backends…

In the meantime I’m delighted that a fairly painless upgrade this morning seems to double pippi’s performance!

Saturday May 10th

Very discouraging middle-of-the-night trial run of the feedback resonator, which barely feeds back, and rattles thinly and badly when it should resonate… it may help to shorten up the connections to the amp and maybe just remove the attenuators… they could be patched into service as knobs with a multiplexer, maybe… four pickups though the wiring somehow seems totally different now. The cardboard membrane sounds really weak until it rattles out of control at weird times (could use a highpass maybe) and the strings respond completely differently.

If I patch the pickups directly into a koma field kit (which is all active/buffered and has extra gain and filters) and then into the amplifier maybe it’ll behave more like it did when I was testing. It just wanted to feed back then… now I wonder if the noise floor is so high that it’s actually suppressing the feedback? Different membranes may help, too. I hope!

Thursday May 8th

Still so much wiring to do, but the sideplate for the electronics sidecar is nearly done. The big red switches connect to the stereo jacks next to them, and the attenuation knobs on the sidecar for toggle muting the pickups. The glowing green LED is connected to the power supply, this breakout on the side has a USB connector for 5v power – which will power the microcontroller awkwardly by snaking a cable through the little hole in the bottom of the plate – and a barrel connector for charging. The LED is always on, I’m not sure why? There’s another set of status LEDs on the supply itself, and the power gets cut on and off through the key switch on the top.

Wednesday May 7th

The cycfi pickups I’m using have nice headers on them, but the power hookups are weirdly at a 2mm spacing. I’m trying to avoid soldering directly to them (though I’ve already done so with one of them) so it’ll be easier to reuse them in different projects, but I don’t have any 2mm female headers and they’re a few weeks away via mail order.

Happily this morning revealed that JST connectors fit snugly on both sides of the pickup and I’ve got the right sizes for both ends! The JST PH connectors fit those 2mm headers perfectly, and the JST XH connectors fit pretty nicely with standard 2.54mm breadboard-sized spacings.

Crimping the connectors isn’t as much of a pain in the butt as I remembered. For sure easier than soldering to headers 2mm spaced apart! This guide helped me remember how – though not before destroying a couple connectors trying to do it from memory.

Two stereo outs, one mixed mono out, and one barrel input for power on the main resonator connecting to two stereo ins and one barrel output for power on the amplifier sidecar routes the channels to the passive attenuators before being mixed into the amplifier… which is stereo. It could be quad with a second board stacked on top, there’s room for the tab breakouts… or it could take a sum from channels 1 and 2 for the left input and a sum from channels 3 and 4 for the right input… or I could treat it like a mono amp, because that’s all it’s driving now…

Tuesday May 6th

Pickup wiring…

Monday May 5th

Some rain families:

• Bowed strings
• Chromatic free reeds
• Feedback resonators
• Tubular blown resonators

(Figuring through forces…)

Sunday May 4th

So much wiring to do! This is a sidecar for the feedback resonator guitar thing which holds the battery and power supply, the amplifier, and an esp32 to send the buttons and switches and etc over wifi. One of the knobs (in blue) is the amplifier gain, and the four grey ones in line next to it are passive attenuation for the pickups. There’s also a knob going to the one ADC on the microcontroller, and an LED for feedback from it. I used this silly key-lock switch for the power because it seemed fun. How long until I lose the key just before a show? Storing the extra one inside the sidecar itself for that likely future happening seems like a reasonable idea. :-p

The side panel will have mute switches for the pickups, too, these red switches feel really nice to toggle. The power supply breaks out for charging on the side, and this is where the pickup audio, power and speaker hookups go too.

Friday May 2nd

It’s bandcamp Friday, and we’ve put a single on the new Cedar AV bandcamp page:

We actually finished an album this year, somehow! Recorded on a houseboat on the mississippi river last year, we finished mixing and doing overdubs at Nick’s wonderful new studio over the winter.

The creatively titled Houseboat Piano Version is Nate doing a solo piano version of one of the songs from the album. LuvSound is doing a small edition of the album later this year after we re-launch sometime this summer.

Thursday May 1st

Blu and co-host otherseas have started a midwest themed radio program called loisirs distribués on Chicago-based internet station Redux. They are exploring a certain midwest sound and I’m listening with interest. It’s also not your typical internet radio playlist mix-dump – it’s real radio with mic breaks and stuff! :-) The second episode features an old He Can Jog track.

Tune in here.