[sdiy] AD/DA schematics? quantizers,etc

Jerry Gray-Eskue jerryge at cableone.net
Thu May 14 04:17:13 CEST 2009


This data sheet has the Resistor and Cap equations to determine frequency on
page 4-Low Power Oscillator.

http://www.synthdiy.com/files/2007/40106.pdf

Note that the Trip points vary see: Guaranteed Trip Point Range on the same
page.

In other words you will have to calibrate the frequency if you want it
precise.

The easiest thing to is to put a variable resistor in and swap a few low
value caps (less than a Micro Farad) and tweak the resistor to get the range
right. Of course this will only work if you have something to measure the
Frequency out with..





-----Original Message-----
From: synth-diy-bounces at dropmix.xs4all.nl
[mailto:synth-diy-bounces at dropmix.xs4all.nl]On Behalf Of Dan Snazelle
Sent: Wednesday, May 13, 2009 8:13 PM
To: mverbos at earthlink.net; synth-diy at dropmix.xs4all.nl
Subject: RE: [sdiy] AD/DA schematics? quantizers,etc




so

first step is complete and successful

i must admit that i am a bit surprised as it doesnt sound too much different
than the aliasers i have built with a jfet and a sample and hold.

one thing...to get the clock up to 400 khz, what cap value should i be using
on my 40106 clock?

maybe getting the bit values lower will sound different but so far i dont
know if this is really worth it

i will say this alleviates the problem of bleedthrough that i get with
analog aliases

thanks





--------------------------------------------
check out various dan music at:

http://www.myspace.com/lossnyc

(updated monthly)

http://www.soundclick.com/lossnyc.htm



http://www.indie911.com/dan-snazelle

(or for techno) http://www.myspace.com/snazelle

ALSO check out Dan synth/Fx projects:

AUDIO ARK:

www.youtube.com/watch?v=TJRpvaOcUic

www.youtube.com/watch?v=BqIa_lXQNTA&feature=channel_page

www.youtube.com/watch?v=V4nJPjGgOcU&feature=channel_page

and soundtrack/design work:

NEW: check out Dan's sound design from the 1998 award winning film SAFARI by
catherine chalmers

http://www.catherinechalmers.com/videos.cfm






----------------------------------------
> CC: synth-diy at dropmix.xs4all.nl
> From: mverbos at earthlink.net
> To: subjectivity at hotmail.com
> Subject: Re: [sdiy] AD/DA schematics? quantizers,etc
> Date: Wed, 13 May 2009 20:34:58 -0400
>
> Dan,
>
> I'd power your opamp from +/-15 as normal, but after the opamp/before
> the AthD put a low valued resistor followed by a diode to +5 and one
> to ground. That will limit the signal swing, preventing the AtoD from
> being hit too hard. That's standard stuff, a bit like what's inside of
> CMOS chips to protect their inputs.
>
> Mark
>
>
>
>
>
> On May 13, 2009, at 7:39 PM, Dan Snazelle wrote:
>
>>
>> oh and what should my in and out opamps be powered off of? i usually
>> use + or - 15 or 12
>>
>> will that still work in this system?
>>
>> it gets confusing with all the vrefs and swing limitations
>>
>> thanks
>>
>>>
>>>
>>>
>>> i know this is a simple question but to gurantee a 0 to 5 volt
>>> swing on the input, is it best to limit the swing with a voltage
>>> divider or to just use an opamp with the signal on the non-
>>> inverting side and an offset with one side going to +V through a
>>> resistor and the other side going to ground?
>>>
>>> i have never had to limit the swing of a signal before
>>>
>>> thanks
>>>
>>> --------------------------------------------
>>> check out various dan music at:
>>>
>>> http://www.myspace.com/lossnyc
>>>
>>> (updated monthly)
>>>
>>> http://www.soundclick.com/lossnyc.htm
>>>
>>>
>>>
>>> http://www.indie911.com/dan-snazelle
>>>
>>> (or for techno) http://www.myspace.com/snazelle
>>>
>>> ALSO check out Dan synth/Fx projects:
>>>
>>> AUDIO ARK:
>>>
>>> www.youtube.com/watch?v=TJRpvaOcUic
>>>
>>> www.youtube.com/watch?v=BqIa_lXQNTA&feature=channel_page
>>>
>>> www.youtube.com/watch?v=V4nJPjGgOcU&feature=channel_page
>>>
>>> and soundtrack/design work:
>>>
>>> NEW: check out Dan's sound design from the 1998 award winning film
>>> SAFARI by catherine chalmers
>>>
>>> http://www.catherinechalmers.com/videos.cfm
>>>
>>>
>>>
>>>
>>>
>>>
>>> ----------------------------------------
>>>> From: jerryge at cableone.net
>>>> To: subjectivity at hotmail.com
>>>> Subject: RE: [sdiy] AD/DA schematics? quantizers,etc
>>>> Date: Wed, 13 May 2009 11:48:56 -0500
>>>>
>>>> Oh and you can get another effect by varying the Clock rate, the
>>>> slower it
>>>> runs the more Chucky the conversions sort of like a bad low pass
>>>> filter as
>>>> lower rates will kill of higher frequencies.
>>>>
>>>> -----Original Message-----
>>>> From: synth-diy-bounces at dropmix.xs4all.nl
>>>> [mailto:synth-diy-bounces at dropmix.xs4all.nl]On Behalf Of Dan
>>>> Snazelle
>>>> Sent: Wednesday, May 13, 2009 11:27 AM
>>>> To: gsn10 at hotmail.com; sdiy
>>>> Subject: RE: [sdiy] AD/DA schematics? quantizers,etc
>>>>
>>>>
>>>>
>>>> oh and by the way, if i want to use switches to turn on and off
>>>> each out of
>>>> the ADC, what should i do? leave it floating instead of to ground?
>>>>
>>>> thanks
>>>>
>>>>
>>>>
>>>> --------------------------------------------
>>>> check out various dan music at:
>>>>
>>>> http://www.myspace.com/lossnyc
>>>>
>>>> (updated monthly)
>>>>
>>>> http://www.soundclick.com/lossnyc.htm
>>>>
>>>>
>>>>
>>>> http://www.indie911.com/dan-snazelle
>>>>
>>>> (or for techno) http://www.myspace.com/snazelle
>>>>
>>>> ALSO check out Dan synth/Fx projects:
>>>>
>>>> AUDIO ARK:
>>>>
>>>> www.youtube.com/watch?v=TJRpvaOcUic
>>>>
>>>> www.youtube.com/watch?v=BqIa_lXQNTA&feature=channel_page
>>>>
>>>> www.youtube.com/watch?v=V4nJPjGgOcU&feature=channel_page
>>>>
>>>> and soundtrack/design work:
>>>>
>>>> NEW: check out Dan's sound design from the 1998 award winning film
>>>> SAFARI by
>>>> catherine chalmers
>>>>
>>>> http://www.catherinechalmers.com/videos.cfm
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> ----------------------------------------
>>>>> From: gsn10 at hotmail.com
>>>>> To: synth-diy at dropmix.xs4all.nl
>>>>> Subject: RE: [sdiy] AD/DA schematics? quantizers,etc
>>>>> Date: Wed, 13 May 2009 11:58:43 -0400
>>>>>
>>>>>
>>>>> That doesn't look like a good circuit design anyway, since it
>>>>> appears to
>>>> short the ADC outputs to ground while leaving the DAC inputs
>>>> floating.
>>>> Circuit bending really hasn't done the world any favors...
>>>>>
>>>>> Anyway, a properly-designed variant of that wouldn't be a bad
>>>>> idea, you
>>>> could even add a "patch bay" between the inputs and outputs and
>>>> map the
>>>> inputs to the outputs any way you want, resulting in some sort of
>>>> primitive
>>>> waveshaper that could probably do some sort of frequency
>>>> multiplication or
>>>> something. For audio purposes it's probably way too nasty but it
>>>> might be
>>>> interesting for CV signals.
>>>>>
>>>>> ----------------------------------------
>>>>>> From: subjectivity at hotmail.com
>>>>>> To: synth-diy at dropmix.xs4all.nl
>>>>>> Subject: RE: [sdiy] AD/DA schematics? quantizers,etc
>>>>>> Date: Wed, 13 May 2009 14:45:44 +0000
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> check this out:
>>>>>>
>>>>>>
>>>>
http://experimentalistsanonymous.com/diy/Schematics/Fuzz%20and%20Fuzzy%20Noi
>>>> semakers/Digital%20fuzz.bmp
>>>>>>
>>>>>> i was going to try and build it as it uses an ADC0808 but he
>>>>>> only labels
>>>> pins up to 20!....so now i dont know if he just didnt touch pins
>>>> 21-28 or if
>>>> i have a totally different chip
>>>>>>
>>>>>> this is all very confusing!
>>>>>>
>>>>>>
>>>>>>
>>>>>> i found another schematic that uses an ADC0804 for the input and
>>>>>> it seems
>>>> VERY different than an adc0808 in that it only has a + and a -
>>>> input instead
>>>> of 8 multiplexed inputs.
>>>>>>
>>>>>>
>>>>>> in general are the ADC08xxx chips pretty easy to switch for
>>>>>> another one
>>>> in the series? or do i need to just go out and order the ADC0804
>>>> if thats
>>>> what it calls for?
>>>>>>
>>>>>> can anyone recommend a good book on AD/DA converters?
>>>>>>
>>>>>> thanks
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> --------------------------------------------
>>>>>> check out various dan music at:
>>>>>>
>>>>>> http://www.myspace.com/lossnyc
>>>>>>
>>>>>> (updated monthly)
>>>>>>
>>>>>> http://www.soundclick.com/lossnyc.htm
>>>>>>
>>>>>>
>>>>>>
>>>>>> http://www.indie911.com/dan-snazelle
>>>>>>
>>>>>> (or for techno) http://www.myspace.com/snazelle
>>>>>>
>>>>>> ALSO check out Dan synth/Fx projects:
>>>>>>
>>>>>> AUDIO ARK:
>>>>>>
>>>>>> www.youtube.com/watch?v=TJRpvaOcUic
>>>>>>
>>>>>> www.youtube.com/watch?v=BqIa_lXQNTA&feature=channel_page
>>>>>>
>>>>>> www.youtube.com/watch?v=V4nJPjGgOcU&feature=channel_page
>>>>>>
>>>>>> and soundtrack/design work:
>>>>>>
>>>>>> NEW: check out Dan's sound design from the 1998 award winning
>>>>>> film SAFARI
>>>> by catherine chalmers
>>>>>>
>>>>>> http://www.catherinechalmers.com/videos.cfm
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> ----------------------------------------
>>>>>>> From: subjectivity at hotmail.com
>>>>>>> To: tom at electricdruid.net
>>>>>>> Subject: RE: [sdiy] AD/DA schematics? quantizers,etc
>>>>>>> Date: Wed, 13 May 2009 13:23:39 +0000
>>>>>>> CC: synth-diy at dropmix.xs4all.nl
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> yes i have actually built quite a few crushers , some of my own
>>>>>>> design.
>>>> they are cool but i am looking for something a bit different
>>>>>>>
>>>>>>> i suppose what i meant was i was interested in changing BOTH
>>>>>>> the sample
>>>> rate AND bit rate of the incoming audio with an AD/DA setup
>>>>>>>
>>>>>>> thanks!
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>> Dan,
>>>>>>>>
>>>>>>>> One quick comment;
>>>>>>>>
>>>>>>>>> i am really trying at first to make:
>>>>>>>>>
>>>>>>>>> a sample rate reducer or crusher
>>>>>>>>
>>>>>>>> These are quite different, reducing the amount of digital data
>>>>>>>> in
>>>>>>>> either the X or the Y direction.
>>>>>>>> For a sample-rate reduction type effect, you should have a
>>>>>>>> look at
>>>>>>>> Tom Bugs' bugcrusher, although it isn't actually reducing any
>>>>>>>> sample
>>>>>>>> rates. Rather it's an audio-rate S&H. Still, similar sound.
>>>>>>>>
>>>>>>>> A real bitcrusher effect would be generated by sampling the
>>>>>>>> input
>>>>>>>> with an A/D, then feeding only the most significant bits (you
>>>>>>>> choose
>>>>>>>> how many) to the output D/A.
>>>>>>>>
>>>>>>>> I've got this effect in software on my digital oscillator. It
>>>>>>>> allows
>>>>>>>> you to reduce the output resolution from 16-bit down to 1-bit.
>>>>>>>> This
>>>>>>>> is further than anyone really needs to go, but it made the
>>>>>>>> control
>>>>>>>> easier to do!
>>>>>>>>
>>>>>>>> HTH,
>>>>>>>> Tom
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> Synth-diy mailing list
>>>>>>> Synth-diy at dropmix.xs4all.nl
>>>>>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>>>>
>>>>>> _______________________________________________
>>>>>> Synth-diy mailing list
>>>>>> Synth-diy at dropmix.xs4all.nl
>>>>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>>>
>>>>> _________________________________________________________________
>>>>> Hotmail® has a new way to see what's up with your friends.
>>>>>
>>>>
http://windowslive.com/Tutorial/Hotmail/WhatsNew?ocid=TXT_TAGLM_WL_HM_Tutori
>>>> al_WhatsNew1_052009
>>>>> _______________________________________________
>>>>> Synth-diy mailing list
>>>>> Synth-diy at dropmix.xs4all.nl
>>>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>>
>>>> _______________________________________________
>>>> Synth-diy mailing list
>>>> Synth-diy at dropmix.xs4all.nl
>>>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>>>>
>>
>> _______________________________________________
>> Synth-diy mailing list
>> Synth-diy at dropmix.xs4all.nl
>> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>

_______________________________________________
Synth-diy mailing list
Synth-diy at dropmix.xs4all.nl
http://dropmix.xs4all.nl/mailman/listinfo/synth-diy




More information about the Synth-diy mailing list