Blog

yo,

so like. in the last post i mentioned burnout? and like honestly im still burnt out as fuck from work despite the week off i took back then. but.... i told myself i'd post about the last module i made before i started breadboarding the next one, and at this point i've got the next one fully designed and there's nothing left that i can do before i start breadboarding it. so i'm forcing myself to post about the last one. its ok tho cos really there's not that much to say about it....

it's a sample and hold module, and if u dont know what that means i think thats normal cos i didn't either until shortly before i started designing it. basically it has 2 inputs, a signal and a trigger, and one output. when the trigger goes high, the module "samples" the voltage of the signal, and "holds" that voltage, which comes out of the output. so u can do stuff like putting noise in as the signal and a clock as the trigger to get random voltages out, then pass that to the pitch input of a vco to get random notes. or if u put an lfo in as the signal instead u get something thats kind of like an arpeggio. it's fun!

as usual my design is kind of a mishmash of other designs, this time it's primarily based on moritz klein's one, but with some adjustments and a glide output based on the mfos design. although, when i say (type?) "adjustments", mostly i mean using an lf444 instead of a tl074, cos with the latter the sampled voltage was drifting really fast, which apparently is due to its "input bias current"¹ being too high? but the lf444's "input bias current" is super low, so i can use an even smaller capacitor for better sampling accuracy and it still holds the signal steady for upwards of 20 seconds². sucks that its more expensive but if i didn't do that it'd be less of a "sample and hold" module and more of just a "sample" module, soo.....

anyway i've been using this basically every time i jam on the synth ever since i made it. i think having a way to generate random notes was something i'd been missing a lot and hadn't even realised? not having full control makes it a lot more fun to play, if that makes sense. if nothing else it definitely makes it less repetitive than when i use a sequencer³. its nice! although, i do kinda wish i made the max glide time longer cos it caps out at around a second as is.... buuuut its not a big deal.

that's all i got to say about it! i've updated the synth page again, schematics are on the repo, etc etc etc. hopefully next time i finish a module it wont take me like 3 months to post about it afterwards. especially cos i actually have enough modules planned out now to take up the rest of the space in my rack, which i think will put a bit more pressure on me to actually make each post before moving onto the next module. and like, maybe the burnout will ease up?? or not. i hope it does tho,

til the next one :O3

– freya