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ArchiverArchiver Posts: 46,084
edited 2004-06-07 18:04 in General Discussion
hey im new to the group and i am interrested in using my basic stamp
II kit to make a simple guitar petal. i was wondering if this is
possible and if so, if anyone knows any good resources for
information on how to go about this. thank you.

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2004-06-01 11:19
    To get started, and for those of us who don't play, exactly what do you want
    the guitar pedal to do?

    Ken
    ==================
    hey im new to the group and i am interrested in using my basic stamp
    II kit to make a simple guitar petal. i was wondering if this is
    possible and if so, if anyone knows any good resources for
    information on how to go about this. thank you.


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-01 16:03
    On Tue, 2004-06-01 at 03:01, joey wrote:
    > hey im new to the group and i am interrested in using my basic stamp
    > II kit to make a simple guitar petal. i was wondering if this is
    > possible and if so, if anyone knows any good resources for
    > information on how to go about this. thank you.

    While you can do some things with the stamp for guitar effects, I
    question the applicability, even from an experimentation standpoint.

    Most effects pedals are based on simple Op-Amp designs (a 50 cent part),
    and generally work by modifying the analog waveform in real-time,
    through various combinations of peak clipping, delay add-ins, harmonics
    generation, etc.

    The stamp isn't ideally suited to pure analog work, and the amount of
    outboard electronics you would need to do anything really interesting
    would probably equal what it would take to just make the effects pedal
    in the "traditional" way.

    I have done some fiddling with effects pedals myself. I will say that
    while the Stamp isn't suited to working with the analog waves directly,
    there are other applications. These applications (for me at least) are
    around things like precision control of input voltage (ie: you can get
    that low-battery effect from a pedal, while operating off of a clean,
    filtered powersupply), or creating the ability to remotely-control
    settings (via 1-wire POT's), or to control multiple pedals (imagine if
    you could network pedals from 3 guitarists on stage, and "tweak" them
    from the soundboard...)
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-01 16:08
    The BS2 doesn't have near enough horsepower to do any real-time audio
    processing. That's why pro-audio gear uses dedicated Sharc DSP (Digital
    Sound Processing) chips. At the very least, anything doing digital sound
    would have to be processing 16-bit wide (two 8-bit words) audio some 40,000
    plus times a second, and spit it out with at most a few milliseconds of
    delay. More than 20 or 30 milliseconds of processing time, and you're
    fighting the delay thing while you're playing your guitar.

    That being said, I have built a bunch of guitar distortion processors that
    were relay switched around 12AX7 tubes and various low-pass and band-pass
    op-amp filters. A BS2 would be a great way to keep track of a bunch of these
    pre-sets, and with the touch of a button call up your various gain, lead,
    rhythm, and power chord settings.

    Be aware that this is pretty involved, and requires a good bit of knowledge
    of filter design, tube design, and audio processing in general. But it's a
    great way to learn about audio signal processing, especially for guitar,
    which is in its own little world.

    Mike Sokol
    mike@f...
    www.fitsandstarts.com


    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"...
    -William of Occam-

    > ==================
    > hey im new to the group and i am interrested in using my basic stamp
    > II kit to make a simple guitar petal. i was wondering if this is
    > possible and if so, if anyone knows any good resources for
    > information on how to go about this. thank you.
    >
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-01 18:00
    > hey im new to the group and i am interrested in using my basic stamp
    > II kit to make a simple guitar petal. i was wondering if this is
    > possible and if so, if anyone knows any good resources for
    > information on how to go about this. thank you.

    I don't think the stamp has enough juice to do DSP but it could act as a
    MIDI interface to analog FX circuits.

    --
    Enjoy,
    George Warner,
    Schizophrenic Optimization Scientists
    Apple Developer Technical Support (DTS)
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-01 22:21
    probably the simplest thing to do with the stamp and FX pedals is to simply
    use the stamp to turn on a certain combination of pedals with the click of
    one button. good for on the fly FX changes.



    Original Message
    From: "George Warner" <geowar@a...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, June 01, 2004 1:00 PM
    Subject: [noparse][[/noparse]basicstamps] re: music


    > > hey im new to the group and i am interrested in using my basic stamp
    > > II kit to make a simple guitar petal. i was wondering if this is
    > > possible and if so, if anyone knows any good resources for
    > > information on how to go about this. thank you.
    >
    > I don't think the stamp has enough juice to do DSP but it could act as a
    > MIDI interface to analog FX circuits.
    >
    > --
    > Enjoy,
    > George Warner,
    > Schizophrenic Optimization Scientists
    > Apple Developer Technical Support (DTS)
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-03 01:21
    The analog pedals are based on op-amps and RC circuits. You could
    potentially do some digital processing with the stamp, but it would have
    to be low enough bit rate to totally trash the fidelity. You could
    probably do a low bit-rate sampler with some ADC's/DAC's in the middle and
    potentially do something interesting with that, but you're not going to be
    able to pull/push 88,200 bytes per direction per channel-second, which is
    CD rates.

    On 1 Jun 2004, Brian wrote:

    > On Tue, 2004-06-01 at 03:01, joey wrote:
    > > hey im new to the group and i am interrested in using my basic stamp
    > > II kit to make a simple guitar petal. i was wondering if this is
    > > possible and if so, if anyone knows any good resources for
    > > information on how to go about this. thank you.
    >
    > While you can do some things with the stamp for guitar effects, I
    > question the applicability, even from an experimentation standpoint.
    >
    > Most effects pedals are based on simple Op-Amp designs (a 50 cent part),
    > and generally work by modifying the analog waveform in real-time,
    > through various combinations of peak clipping, delay add-ins, harmonics
    > generation, etc.
    >
    > The stamp isn't ideally suited to pure analog work, and the amount of
    > outboard electronics you would need to do anything really interesting
    > would probably equal what it would take to just make the effects pedal
    > in the "traditional" way.
    >
    > I have done some fiddling with effects pedals myself. I will say that
    > while the Stamp isn't suited to working with the analog waves directly,
    > there are other applications. These applications (for me at least) are
    > around things like precision control of input voltage (ie: you can get
    > that low-battery effect from a pedal, while operating off of a clean,
    > filtered powersupply), or creating the ability to remotely-control
    > settings (via 1-wire POT's), or to control multiple pedals (imagine if
    > you could network pedals from 3 guitarists on stage, and "tweak" them
    > from the soundboard...)
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and Body of the message will be ignored.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >
    >

    Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
    Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
    email: lamont@a... WWW: http://www.serv.net
    "Do not fear mistakes, There Are None" - Miles Davis
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-03 01:24
    It occurs to me that you could probably use one of the
    digitally-controllable resistors that have been mentioned on this list
    before to do some fairly cool stuff with analog filtration. For instance,
    you could use a BS2 to listen on a midi port, receive channel control
    information, and change RC values on an X-pass filter, digitally. This
    could be a pretty cool app, like a mini-midiverb.

    On Tue, 1 Jun 2004, Mike Sokol wrote:

    > The BS2 doesn't have near enough horsepower to do any real-time audio
    > processing. That's why pro-audio gear uses dedicated Sharc DSP (Digital
    > Sound Processing) chips. At the very least, anything doing digital sound
    > would have to be processing 16-bit wide (two 8-bit words) audio some 40,000
    > plus times a second, and spit it out with at most a few milliseconds of
    > delay. More than 20 or 30 milliseconds of processing time, and you're
    > fighting the delay thing while you're playing your guitar.
    >
    > That being said, I have built a bunch of guitar distortion processors that
    > were relay switched around 12AX7 tubes and various low-pass and band-pass
    > op-amp filters. A BS2 would be a great way to keep track of a bunch of these
    > pre-sets, and with the touch of a button call up your various gain, lead,
    > rhythm, and power chord settings.
    >
    > Be aware that this is pretty involved, and requires a good bit of knowledge
    > of filter design, tube design, and audio processing in general. But it's a
    > great way to learn about audio signal processing, especially for guitar,
    > which is in its own little world.
    >
    > Mike Sokol
    > mike@f...
    > www.fitsandstarts.com
    >
    >
    > " One should not increase, beyond what is necessary,
    > the number of entities required to explain anything"...
    > -William of Occam-
    >
    > > ==================
    > > hey im new to the group and i am interrested in using my basic stamp
    > > II kit to make a simple guitar petal. i was wondering if this is
    > > possible and if so, if anyone knows any good resources for
    > > information on how to go about this. thank you.
    > >
    > >
    > > [noparse][[/noparse]Non-text portions of this message have been removed]
    > >
    > >
    > >
    > > To UNSUBSCRIBE, just send mail to:
    > > basicstamps-unsubscribe@yahoogroups.com
    > > from the same email address that you subscribed. Text in the Subject and
    > Body of the message will be ignored.
    > >
    > > Yahoo! Groups Links
    > >
    > >
    > >
    > >
    > >
    > >
    > >
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and Body of the message will be ignored.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >
    >

    Sean T. Lamont, CTO / Chief NetNerd, Abstract Software, Inc. (ServNet)
    Seattle - Bellingham - Vancouver - Portland - Everett - Tacoma - Bremerton
    email: lamont@a... WWW: http://www.serv.net
    "Do not fear mistakes, There Are None" - Miles Davis
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-07 14:59
    Kevin,

    I'm certainly willing to muse about this topic within the forum, but perhaps
    the audio/music elements may be a bit too far off topic.

    To elaborate a bit, we're talking about design basics for tube-based audio
    processing. Some 25-plus years ago, I built a bunch of tube-based guitar
    processors that acted like tiny guitar amplifiers, but without any power to
    drive speakers. This was before there were MIDI-based guitar processors, so
    I used IC's packs of AND and OR gates to hardwire the logic needed to
    memorize a bunch of desired presets.

    Of course, by doing all the control logic with a BS, you would be able to
    store as many presets as you like, and change them on a whim. I had to get
    out the wire-wrap tool to make any changes in the logic in my early designs.

    That being said, I'll leave it up to the moderator as to the suitability of
    this topic to post on the forum.

    What do you think, Jon? Too far off-topic, or is BS control of tube audio
    processing circuits of sufficient interest for the group? If it's too far
    OT, I'll take this up with Kevin off line.

    Mike Sokol
    mike@f...
    www.fitsandstarts.com


    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"...
    -William of Occam-
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-07 17:43
    Jon Williams...

    Kevin Lavigne has contacted me about help with a design for a BS controlled
    guitar processor. I've built a bunch of tube-based audio crunch boxes a long
    time ago, and think it would be interesting to contemplate adding Basic
    Stamp control to them.

    For instance, by varying the power supply to the plate of a 12AX7 tube, you
    can go from clean audio mode (using high-voltage: 150 volts DC or so) to
    dirty crunch starved mode (low voltage (using 50 volts DC or so). This would
    involve things like a BS controlled HV supply (not too difficult for the
    few milliamps needed by a signal triode). We would also explore topics like
    setting audio gain levels and filter boost/cuts via a Stamp using VGA or DGA
    circuits (voltage or digitally controlled amplifier).

    Knowing full well that many of the tech-heads on this site used to play in
    bands of all sorts from blues, to rock to glam, perhaps this would an
    interesting topic for the group at large. I'm not worried about propriety
    circuit design... I just want everyone to get their Strats out of the closet
    and throw in their 2 bits about digitally controlled tube design for audio
    (inflation up from 2 cents).

    Everyone please note that this IS NOT about trying to use a Basic Stamp to
    process the audio itself, only to control an outboard circuit that would do
    the actual distortion, compression, etc.

    So Jon, is this suitable for a Basic Stamp discussion, or do we take it to
    the seedy underground world of analog electronics?

    P.S. I think those with the coolest design ideas should post their stage
    pictures from 30 years ago. Mine are pretty scary....

    Mike Sokol
    mike@f...
    www.fitsandstarts.com

    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"...
    -William of Occam-


    Original Message
    From: "Kevin Lavigne" <klavigne@c...>
    To: "Mike Sokol" <mike@f...>
    Sent: Monday, June 07, 2004 12:15 PM
    Subject: Re: [noparse][[/noparse]basicstamps] music


    > Hi Mike,
    > I originally contacted you off-line due to off-topic concerns and the
    > thought that you might not want to divulge any 'trade secrets' to the
    > general populace.
    > Since it seems that neither of these concerns are in effect yet, I'll be
    > happy to converse within this group.
    >
    > To get everyone up to speed.....
    > I'm thinking of creating a BS2 controlled tube pre-amp for use with my
    > Guitar and existing power amp.
    > This pre-amp should be able to produce a nice bluesy overdrive up to a
    heavy
    > crunch/distortion.
    > I'm thinking that I may have to use two tube circuits to achieve this one
    > specifically tuned to the overdrive effect and another tuned for heavy
    > crunch/distortion.
    > Switching/mixing between the two of these shouldn't be much of an issue
    with
    > digital pots and the BS2.
    > From what I've gathered a 12AX7 based circuit/s should be able to
    > accommodate this but I'll take any suggestions.
    > The BS2 will use digital pots to adjust the tube circuit parameters.
    > Presets will be programmed using up/down buttons with a LCD providing user
    > feedback.
    > Of course the presets will be stored in EEPROM for alter recall.
    > Once this is working I'll probably add a MIDI interface (Slave only) so
    that
    > changes during a gig can be set by signals from a keyboard (MIDI not PC)
    or
    > a PC.
    >
    > The functionality for the BS2 point of view is already well covered, I was
    > looking more for help in the tube circuit design area and
    > digital/analog/Tube noise issues to watch for.
    >
    > Thanks Mike!
    >
  • ArchiverArchiver Posts: 46,084
    edited 2004-06-07 18:04
    If you're going to use a BASIC Stamp to control the guitar processor,
    have at it.

    -- Jon Williams
    -- Applications Engineer, Parallax
    -- Dallas Office


    Original Message
    From: Mike Sokol [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=QI3qPy2zMUrwIyjxiQzoOm1iZGlC4sRvOTSsTCS-SlTCkwxhOJgEezmVaZj2H7pORCLy-28QrZVdl7BUD168Nw]mike@f...[/url
    Sent: Monday, June 07, 2004 11:43 AM
    To: basicstamps@yahoogroups.com
    Subject: Fw: [noparse][[/noparse]basicstamps] music


    Jon Williams...

    Kevin Lavigne has contacted me about help with a design for a BS
    controlled guitar processor. I've built a bunch of tube-based audio
    crunch boxes a long time ago, and think it would be interesting to
    contemplate adding Basic Stamp control to them.

    For instance, by varying the power supply to the plate of a 12AX7 tube,
    you can go from clean audio mode (using high-voltage: 150 volts DC or
    so) to dirty crunch starved mode (low voltage (using 50 volts DC or so).
    This would involve things like a BS controlled HV supply (not too
    difficult for the few milliamps needed by a signal triode). We would
    also explore topics like setting audio gain levels and filter boost/cuts
    via a Stamp using VGA or DGA circuits (voltage or digitally controlled
    amplifier).

    Knowing full well that many of the tech-heads on this site used to play
    in bands of all sorts from blues, to rock to glam, perhaps this would an
    interesting topic for the group at large. I'm not worried about
    propriety circuit design... I just want everyone to get their Strats out
    of the closet and throw in their 2 bits about digitally controlled tube
    design for audio (inflation up from 2 cents).

    Everyone please note that this IS NOT about trying to use a Basic Stamp
    to process the audio itself, only to control an outboard circuit that
    would do the actual distortion, compression, etc.

    So Jon, is this suitable for a Basic Stamp discussion, or do we take it
    to the seedy underground world of analog electronics?

    P.S. I think those with the coolest design ideas should post their stage
    pictures from 30 years ago. Mine are pretty scary....

    Mike Sokol
    mike@f...
    www.fitsandstarts.com

    " One should not increase, beyond what is necessary,
    the number of entities required to explain anything"... -William of
    Occam-


    Original Message
    From: "Kevin Lavigne" <klavigne@c...>
    To: "Mike Sokol" <mike@f...>
    Sent: Monday, June 07, 2004 12:15 PM
    Subject: Re: [noparse][[/noparse]basicstamps] music


    > Hi Mike,
    > I originally contacted you off-line due to off-topic concerns and
    > the thought that you might not want to divulge any 'trade secrets' to
    > the general populace. Since it seems that neither of these concerns
    > are in effect yet, I'll be happy to converse within this group.
    >
    > To get everyone up to speed.....
    > I'm thinking of creating a BS2 controlled tube pre-amp for use with my

    > Guitar and existing power amp. This pre-amp should be able to produce
    > a nice bluesy overdrive up to a
    heavy
    > crunch/distortion.
    > I'm thinking that I may have to use two tube circuits to achieve this
    > one specifically tuned to the overdrive effect and another tuned for
    > heavy crunch/distortion. Switching/mixing between the two of these
    > shouldn't be much of an issue
    with
    > digital pots and the BS2.
    > From what I've gathered a 12AX7 based circuit/s should be able to
    > accommodate this but I'll take any suggestions. The BS2 will use
    > digital pots to adjust the tube circuit parameters. Presets will be
    > programmed using up/down buttons with a LCD providing user feedback.
    > Of course the presets will be stored in EEPROM for alter recall.
    > Once this is working I'll probably add a MIDI interface (Slave only)
    so
    that
    > changes during a gig can be set by signals from a keyboard (MIDI not
    > PC)
    or
    > a PC.
    >
    > The functionality for the BS2 point of view is already well covered, I

    > was looking more for help in the tube circuit design area and
    > digital/analog/Tube noise issues to watch for.
    >
    > Thanks Mike!
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