Crystal Filters

[BKr0n]

Have been looking around the web at odd filter designs and these showed up (https://en.m.wikipedia.org/wiki/Crystal_filter). They seem to be used in rf filters a bit. What's the efficacy of them for audio? Can they be used in something like an ordinary analog filter?

 

[voodooless]

What's the efficacy of them for audio?

Balsically none. There are basically no crystals working at audible frequencies, nor do we need filters with very high Q’s.

Also, for RF, things like distortion are way less import than in audio. I bet these filters aren’t doing very well distortion wise.

 

[fpitas]

Balsically none. There are basically no crystals working at audible frequencies, nor do we need filters with very high Q’s.

Also, for RF, things like distortion are way less import than in audio. I bet these filters aren’t doing very well distortion wise.

That's not really a problem for RF since they're so narrowband. But I have no idea what you'd do with one for audio, unless you want just one note, ringing for several seconds afterwards

 

[BKr0n]

That's not really a problem for RF since they're so narrowband. But I have no idea what you'd do with one for audio, unless you want just one note, ringing for several seconds afterwards

I was actually thinking more along the lines of anti-aliasing filters for an ADC. I figured the super high Q would be great for that.

 

[fpitas]

I was actually thinking more along the lines of anti-aliasing filters for an ADC. I figured the super high Q would be great for that.

You mean, somehow include one as a resonator? Even used that way, a high-Q filter corner will ring.

 

[BKr0n]

Well poo. Guess it's back to the drawing board.

 

[fpitas]

The sharper the filter cutoff, the more the step response rings. Mother Nature has it in for us

 

[voodooless]

I was actually thinking more along the lines of anti-aliasing filters for an ADC. I figured the super high Q would be great for that.

Why? You don’t need super sharp or steep analog filters because of the digital filters in the oversampling bit.

 

[BKr0n]

The sharper the filter cutoff, the more the step response rings. Mother Nature has it in for us

Oh great another overbearing mother

Why? You don’t need super sharp or steep analog filters because of the digital filters in the oversampling bit.

I wanted to use a SAR for real time signal processing. Figured if I was in the MHz range it wouldn't make a difference. Turns out I was wrong.

 

[voodooless]

I wanted to use a SAR for real time signal processing.

Still at it I see… rolling your own ADC should be way down on your priority list.

 

[BKr0n]

Still at it I see… rolling your own ADC should be way down on your priority list.

I'm not a fan of calling it quits. If I want it a certain way, I need to put the work in. All there is to it.

 

[voodooless]

I'm not a fan of calling it quits. If I want it a certain way, I need to put the work in. All there is to it.

Are you also building a DIY nuclear reactor if you need to power your house instead of getting solar panels and a battery?

 

[AdamG]

Are you also building a DIY nuclear reactor if you need to power your house instead of getting solar panels and a battery?

A pocket portable nuclear reactor has always been a dream of mine. Unfortunately I keep running into paperwork and approval issues. So many rules and regulations that stifle innovation and creativity. Bubbleheads take this stuff seriously.

 

[mhardy6647]

A pocket portable nuclear reactor has always been a dream of mine. Unfortunately I keep running into paperwork and approval issues. So many rules and regulations that stifle innovation and creativity. Bubbleheads take this stuff seriously.

Plus that lead-lined pocket would make the shirt a bit of a bother to wear, especially in hot weather, I'd think.


EDIT: w -a - i - t... or are you thinkin' of a coat pocket reactor...
enlightenment dawns.

 

[BKr0n]

Are you also building a DIY nuclear reactor if you need to power your house instead of getting solar panels and a battery?

Dude if I did I'd be making a lot more money than I am now lmao

 

[Prana Ferox]

I have no idea what you'd do with one for audio, unless you want just one note, ringing for several seconds afterwards

Bands like Sunn O))) have made a career out of this

 

[BKr0n]

Bands like Sunn O))) have made a career out of this

Drone metal? Does that mean they fly around on stage?

 

[AnalogSteph]

Crystal Equivalent Circuit

Learn more about how the parameters of a quartz crystal circuit can be customized through design.

suntsu.com

Tell me how you're going to use that in a lowpass filter.

 

[fpitas]

If you do get it to work though, you can honestly claim crystal-clear highs.

 

[DVDdoug]

If you do get it to work though, you can honestly claim crystal-clear highs.

Tell me how you're going to use that in a lowpass filter

Right... It's a "tuned circuit" (or "device") that can work in a bandpass or notch filter but we want a low-pass filter that passes everything in the audio range (or everything below the Nyquist limit) while blocking all higher frequencies.

I was actually thinking more along the lines of anti-aliasing filters for an ADC. I figured the super high Q would be great for that.

Anti-aliasing seems to be a "solved problem". I've never heard aliasing, I've only heard-of it. I could probably intentionally create it by writing a "stupid" down-sampling algorithm.