I have a strobe light which has a xlr input for a 10v trigger. I want to get this to flash in time to some music, I thought i could make a cuircuit which would high pass a audio signal so i just get the hi hats / cymbols and use this to switch a 10v charge. I dont have much experience, so i need something simple or a schematic to follow. I was also thinking about getting a pic like the arduino or pic16f84 and writing a program to similar effect. Advice and help much appreciated thanks tim
10v Trigger for strobe
Jun 05, 2007
4 Replies
How much experience is not much, and how complicated do you want to make it? Digital signal processing is way overkill in my opinion - but what are your needs? What do you expect to do and why? How good does it need to be? Since you say XLR I assume your 're talking about the microphone, stage, or professional musician's audio connector? Is this for a multimillion dollar application or garage band?
Flash in time with some music . . . would imply the bass beat to me, not the cymbals, since you have ride and crash cymbals as a rule - and I doubt a simple filter could distinguish between a cymbal crash and a rim shot.
Another reason to go for the bass drum - it is closer to a clean sine wave where the cymbal is more like noise - a great many frequencies together.
Just my two cents.
What you want to search for are schematics for high pass (cymbals) or low pass (bass drum) filters. "The Op Amp Cookbook" would be good but you should/may find something with Google. Microphone, pre amp, filter, XLR connector.
A PIC for this is unduly complicated and wouldn't really add much - you still need to detect the sound, amplify it, and filter it - the PIC could filter it providing the clock is fast enough and your code is slim enough - but a single op amp with a cap in the feedback will do more for less effort. A pic may be easier to modify - but analog active filters can be easily made tunable with variable resistors or switching in different caps.
Basic concepts
formatting link
Stops low frequency allows high frequency through
formatting link
Opposite of high pass
formatting link
Lets a specific frequency through - tune it to one note
More advanced
formatting link
more than you want to know, but the Butterworth is commonly used for this type of function.
A real application
formatting link
Another guy doing things the hard way using a switched capacitor filter using a single chip designed for the purpose.
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+
Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----
formatting link
From the active filter cookbook simple low pass schematics
formatting link
ditto high pass
--
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
formatting link
The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----
you probably want to make a notch filter, for the hi hat range, then use that to trigger a monostable to give the strobe a bit of time. if you don't have much experience then learn what a buffer is, so that each part of the circuit works on its own, without loading the next bit. forget the pic.
robert
formatting link
--
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
formatting link
The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----
Join the Discussion
Have something to add? Share your thoughts — no account required.
Didn't find your answer?
Ask the community — no account required