Edit my project to run in real world

Discussion in 'The Projects Forum' started by Precious Molina, Sep 10, 2015.

  1. Precious Molina

    Thread Starter New Member

    Sep 6, 2015
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    can you please help me I spent alot of time researching/reading but its imposible
    i dont know about electronics calculation, im an audio engineer
    im just depending on tina spice, would you please check/edit this

    In spice my opamp and eq filter simulation seems Good, but i dont know in real world
    whats my side effect
    cant access any opamp only 5532 and op27
    i choose low value to reduce noise specially in first stage, i love low noise, SNR
    i dont care about size and or how much he draw current, since i have power supply -/+9v


    Mic 500 ohm
    stage1 gain 1000x
    stage2 limiter
    stage3 lowpass
    stage4 Fet mojo and negative clipper

    i would really appreciate your help

    http://i1006.photobucket.com/albums/af190/preciousmolina666re/JR MIC PREAMP FINISH_zpsgfjlwikm.jpg

    [​IMG]
     
  2. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    The 5534 is an excellent opamp for audio, but a gain of 1000 in a single stage is a lot to ask for. At 20 kHz there will be only about 10 dB of negative feedback, so noise, distortion, and output impedance all will increase.
    The opamp lowpass filter corner freq is 318 kHz. Why so high? The feedback loop will not be closed at that freq and gain, so the opamp's internal compensation will provide a lowpass effect.
    The overall circuit gain will change as you adjust the lowpass filter pot.
    What is the purpose of the negative-peak-clipper at the output stage?

    ak
     
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  3. Precious Molina

    Thread Starter New Member

    Sep 6, 2015
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    if i add another stage it will add another noise, so whats the highest you think he can?

    is that 10p and 50k? i dont know i just want my 20khz flat, maybe ill remove 10p

    just for adding a little distortion
     
  4. DerStrom8

    Well-Known Member

    Feb 20, 2011
    2,428
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    What on earth are these transistors doing?

    upload_2015-9-10_12-28-31.png
     
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  5. tcmtech

    Well-Known Member

    Nov 4, 2013
    2,034
    1,640
    I think they are relevant to the "fat mojo" circuit. :rolleyes:

    No. Wait, that's a 'fet mojo' circuit so I dunno. :oops:
     
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  6. Precious Molina

    Thread Starter New Member

    Sep 6, 2015
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    im just using it as a diode clipper/distortion?, led and silicon have different character distortion (in spice), i dont know transistor
     
  7. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    Whenever a large community of non-tech or slightly-tech people (especially artists of any kind) deal with tech, myths and legends arise over time. Such is the case with fuzz boxes, electronic circuits that intentionally distort an audio signal with clipping or some other form of non-linear signal transformation. Different clip circuits gain reputations, and descriptions involving color, taste, feel, etc. Fuzz boxes from the 60's and 70's are meticulously maintained today and can command thousand-dollar prices because of their "legendary" sound. Tom Scholz, founder of the band Boston, built a multi-million dollar electronics company based on his fuzz box design.

    Because LEDs and standard diodes (1N914, 1N4004, etc.) have noticeably different V/I curves, they produce different harmonic fields, and thus noticeably different audible characteristics when applied as the non-linear elements. I've seen strange transistor configurations such as in this thread's schematic before, but I think stories about their effects fall more in the myth area.

    A friend who is a research electrochemist in Canada has developed a new type of carbon-based semiconductor. A fuzz box based on it is getting excellent reviews.

    ak
     
  8. Precious Molina

    Thread Starter New Member

    Sep 6, 2015
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    true

    im going to change my first stage to transistor spice said transistor is more quiter, is this true?
     
  9. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    Your first stage is an opamp with a gain of 1000, very low noise and almost zero distortion. There is no transistor that can do that.

    ak
     
  10. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    3,780
    934
    Wouldn't two stages of op amps with gains of a little over 30 be easier to implement and also allow you to simplify your filtering?
     
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  11. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    Yes and yes. And, since the noise is uncorrelated, lower noise.

    ak
     
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  12. Precious Molina

    Thread Starter New Member

    Sep 6, 2015
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    should i change my first stage to this(picture below), if its add distortion its ok, i care about only is noise, and waht happen if i 1000x gain that ne5532, should i need a buffer after that?


    2stage and noise
    3333.jpg
    transistor version
    bjt.JPG
     
  13. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Buffer depends on what load you are driving. If it just goes out to a guitar amp, then no. The amp is not drawing much from this pedal. It is like pushing current through a 250k to 2M resistor depending on the amp.

    If you are trying to drive a pair of headphones, then yes, this amp cannot drive headphone speakers at any decent volume and without some sag in the output voltage.

    NOTE: your statement above is "I have a +/-9 v power supply." If true, why is your latest version of Tina model using +/-18V. You are going to run out of voltage and hard clip with the amount of gain shown if you are using a 9v supply.
     
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  14. Precious Molina

    Thread Starter New Member

    Sep 6, 2015
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    my input is Mic 500ohm dynamic

    oh i forgot to change it to +/-9
     
  15. Sinus23

    Member

    Sep 7, 2013
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    Beside Kraftwerk I've pretty much never heard a decent song made by a person which has made synthesizers or sound effects. I've heard samples by people which have build their own synths or sound effects they made to show you what it can do but that is pretty much it(Too. much. logic. can't. express. my. emotions.:p). But those who did not build the thing and could not give a crap about how it works some of them make plenty of songs and some quite proper too.

    You're confusing audiophools and posers with people which just want to make music that they like ;)
     
    Last edited: Sep 12, 2015
  16. Sinus23

    Member

    Sep 7, 2013
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    Sorry I was just getting a bit tired of the audiomangling bashing on this forum. I know distorting anything is alien to our practices but when you're creating a certain sound it becomes necessary.:oops:
     
  17. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    I'm sorry for your loss.

    ak
     
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  18. Precious Molina

    Thread Starter New Member

    Sep 6, 2015
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    so what i s better on my dynamic mic 500ohm low noise, opamp or transistor?
     
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