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bitcrusher?

Posted: Fri Dec 25, 2009 7:01 pm
by jamiejamiejam
this is the first time i've used a bitcrusher. i've assigned it to a wobble from albino in FL and have it set on the 3rd type 5bit type and 6 downsampling and it is a good sound that i want but changing the downsampling gives it a high freq ring and its annoying an i can't eq it out. this is probably just me not knowing how to use a bitcrusher but why does it ring when i downsample?

Re: bitcrusher?

Posted: Sat Dec 26, 2009 12:16 am
by tripaddict
hmm interesting never tried oscillating a bit crusher :) might give it a go

sounds like you need to restrict the high range on your osc :)

Re: bitcrusher?

Posted: Sat Dec 26, 2009 6:48 am
by futures_untold
To understand the functioning of bitcrushers we must first understand the functioning of digital electronics.

Computers use bits to form the words that describe digital information. This is much like the alphanumeric symbols used to form the words that describe Western languages in writing.

Computers use bits because they are easily implemented mechanically using electronic components. (The physical 'on/off' state of a electronic componant gives us one binary digit (bit). Electronic components, like the flip flop, gate or switch, have two states, either 'on' or 'off'. When the components state is on, electricity can flow through, when the gate is off, electricity cannot flow through).

Each sample of a digital signal is described using words formed of bits. Using more bits allows for longer word lengths. Greater word lengths allow a greater accuracy in the description of the signal.

Bit crushers reduce the amount of bits used to describe a signal. A side effect of this reduction is a change to the signal shape, which we hear as ringing.

The ringing is caused by the reduction of the word length (amount of bits) used to describe each sample of the digital signal. As we reduce the number of bits used to describe the sound, the signal becomes 'stepped' (more square like), and the harmonic structure of the signal changes.

So, it would be more accurate to call a bit 'crusher' a bit 'reducer'! :)

In practical terms, the only method of reducing this ringing is to use filters. If you know the fundamental frequency of your signal, you could use a notch filter to reduce the volume of the higher frequency even harmonics with accuracy. This will reduce the ringing somewhat, but filtering the inhamrmonic signals will still be a problem. If you don't like the ringing, use a different distortion method.

For further information on digital signals, I'd recommend reading the articles found here ---> http://www.bores.com/courses/intro/basics/index.htm and using Wikipedia to follow up on any other terms or concepts that you wish to understand.

(Perhaps Macc or Sharmaji can correct any mistakes in my explanation?)

Re: bitcrusher?

Posted: Sat Dec 26, 2009 1:56 pm
by deadly_habit
:u:

Re: bitcrusher?

Posted: Sat Dec 26, 2009 4:53 pm
by futures_untold
What's up with you Mr Deadly? :lol:

Ooh ar, I forgot to mention sampling rates, and that relates directly to why you hear ringing with lower oversampling settings.

Changing the signal shape (via bit reduction) causes different harmonics to be produced. At a sampling frequency of 44,100, the harmonics introduced to the signal cannot be accurately reproduced. With higher oversampling settings, digital reconstruction filters are employed to smooth the signal to be as accurate as possible at 44,100.

Plugins that employ oversampling are in fact operating internally at a sampling frequency greater than the host software. The greater the oversampling setting, the more accurate and thus 'cleaner' the sound wil be.

Sadly I don't fully understand this shit myself, so you are advised to read up on sampling, oversampling and bit reduction yourself!.

Pat :)

Re: bitcrusher?

Posted: Sat Dec 26, 2009 6:22 pm
by deadly_habit
first thread ni read this morning combined with a big hangover and having to go to work
:lol:

Re: bitcrusher?

Posted: Sun Dec 27, 2009 12:21 pm
by jamiejamiejam
futures_untold wrote:What's up with you Mr Deadly? :lol:

Ooh ar, I forgot to mention sampling rates, and that relates directly to why you hear ringing with lower oversampling settings.

Changing the signal shape (via bit reduction) causes different harmonics to be produced. At a sampling frequency of 44,100, the harmonics introduced to the signal cannot be accurately reproduced. With higher oversampling settings, digital reconstruction filters are employed to smooth the signal to be as accurate as possible at 44,100.

Plugins that employ oversampling are in fact operating internally at a sampling frequency greater than the host software. The greater the oversampling setting, the more accurate and thus 'cleaner' the sound wil be.

Sadly I don't fully understand this shit myself, so you are advised to read up on sampling, oversampling and bit reduction yourself!.

Pat :)
I half expected some guy who thought he was a producer to start bitching at me but that and you previous answer helps a lot. i just liked the sound it made haha. But cheers,

Re: bitcrusher?

Posted: Wed Dec 30, 2009 8:03 pm
by jsills
you might try increasing the bitrate to eliminate some of the ringing. the lower the bitrate, the more distortion and artifacts come through.

Re: bitcrusher?

Posted: Wed Dec 30, 2009 8:13 pm
by Sharmaji
bitcrush. make it sound nasty. then just lopass to get rid of the ringing.

can't think of a mix in the last 3 years that i've done (including rock material) that hasn't included bitcrushing in some way/shape/form. even just taking something down to 12 bits does wonders for "vibe"

Re: bitcrusher?

Posted: Wed Dec 30, 2009 10:59 pm
by jamiejamiejam
it was the order i was eq'ing and bitcrushing in that was the problem and not alllowing the e'ing to work properly. i put the eq on a send channel instead and now i can eq fine. there is still high end even though i have filtered out anything above 300hz lol but whatever it sounds cool.