Hey guys. This is my first post, but I'm sure there will be many more.
I'm a musician, and over the past couple of years I've been experimenting with building my own effects (stompboxes and the like). I don't have any formal education in this area, but so far, I've managed fairly well on my own. That said, I'm starting on a new effect (still in the pre-planning stages), and I have a few questions.
The effect is an analog audio delay. (I'd prefer to implement the effect as a digital delay, but I think I would need to use a full-blown DSP for that, and that's just beyond my means at this point.) I've done some reading, and I've learned a bit about how I should go about it, but I'm a little fuzzy on BBDs. I can't really find much helpful info on the internet, so I'm hoping that some of you have had some experience with BBDs and will be able to shed some light on the subject for me.
So here are my questions:
I'm a musician, and over the past couple of years I've been experimenting with building my own effects (stompboxes and the like). I don't have any formal education in this area, but so far, I've managed fairly well on my own. That said, I'm starting on a new effect (still in the pre-planning stages), and I have a few questions.
The effect is an analog audio delay. (I'd prefer to implement the effect as a digital delay, but I think I would need to use a full-blown DSP for that, and that's just beyond my means at this point.) I've done some reading, and I've learned a bit about how I should go about it, but I'm a little fuzzy on BBDs. I can't really find much helpful info on the internet, so I'm hoping that some of you have had some experience with BBDs and will be able to shed some light on the subject for me.
So here are my questions:
- What would be a good BBD to use? None of the major distributors (Mouser, DigiKey, etc.) seem to have ANY in stock, so I'm not sure what kind of BBDs are out there or how they compare to each other. The Panasonic MN3205 looks good, but I haven't been able to find a pinout or much info aside from an old basic datasheet. (Keep in mind that this is for an audio delay effect, so a high maximum delay time [up to 1 or 2 seconds] is preferred.)
- How difficult is it to use a BBD for this purpose? Can I just connect an analog signal source and a clock to the chip, then run the output through a low-pass filter, or is it more involved than that? (I understand the concept of feedback, but I'm just concerned with delaying the signal for now.)
- Can I use any clock source, or do I have to use a special BBD driver?
- Do most recently produced BBDs have their own LP filter built in, or will I need to make my own? Also, it seems to me that the cutoff frequency for the filter should be the same as (or slightly lower than) the frequency of the clock. Is this so?
- I've noticed that some analog delays use a compander as well. Is this a necessity, or does it just make the signal smoother/cleaner somehow?
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