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metal_head_82
Joined: Dec 27, 2009 Posts: 34 Location: Germany
Audio files: 2
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Posted: Sun Apr 11, 2010 11:29 am Post subject:
One-Shot Circuit 555 or Transistors? |
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Hey there!
I'm currently building a simple drum and percussion synth. And now I'm dealing with the envelope generation for pitch sweep and the vca.
The EG should only generate Release. And for that reason I need a monostable multivibrator. So far so good
And now - here's my question:
I'm pretty new to all that electronic stuff and I'm not quiet sure what type of circuit will be better for my little noise machine - a circuit usind a 555 timer or the good old transitor monostable.
I ran some simulations and both work but most simulators use ideal components. I need to know which circuit is more reliable and works best. As far as I know, the 555 circuit has a lower part count and will need less space on a PCB. So could someone please help me out?
Thx in advance. _________________ "I don't care much about music. What I like is sounds." |
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JovianPyx
Joined: Nov 20, 2007 Posts: 1988 Location: West Red Spot, Jupiter
Audio files: 224
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Posted: Sun Apr 11, 2010 12:29 pm Post subject:
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My Opinion:
I doubt that you'll hear a difference in sound between a discrete transistor one shot and an IC type.
That said, the 555 is a bipolar part which crowbars the powersupply for an instant during output switching. This causes a power supply glitch that might affect other circuits powered by the same supply.
Use a 7555 timer instead - these are pin for pin replacements for the 555 timer, but are made from CMOS and do not crowbar the power supply. Any circuit designed for a 555 timer should work properly (better actually) with a 7555 timer. _________________ FPGA, dsPIC and Fatman Synth Stuff
Time flies like a banana. Fruit flies when you're having fun. BTW, Do these genes make my ass look fat? corruptio optimi pessima
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metal_head_82
Joined: Dec 27, 2009 Posts: 34 Location: Germany
Audio files: 2
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Posted: Sun Apr 11, 2010 12:41 pm Post subject:
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The impact on sound won't be there. This circuit is just meant to do a short one-shot for about 5ms or so.
Just enough to do the attack for the envelope. After attack it goes straight to release. So that trigger impulse won't be able to effect the sound. But if the 555 messes with my power supply I'd better use a transistor circuit oder a 7555 IC.
But as I don't know when I'll place an order at the electronic store, I'll try a transistor version first.
Thx _________________ "I don't care much about music. What I like is sounds." |
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metal_head_82
Joined: Dec 27, 2009 Posts: 34 Location: Germany
Audio files: 2
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Posted: Tue Apr 20, 2010 3:16 am Post subject:
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Little update:
Placed an order at my preferred tech-dealer and got the parts today. Will try a circuit with the 7555 as soon as my noise generator problem is solved...
Topic here: http://electro-music.com/forum/topic-41286.html
Yeah... Extreme Crossposting _________________ "I don't care much about music. What I like is sounds." |
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