DIY attenuator

Discussion in 'Burnt Fingers DIY Effects' started by Cantbreak100guy, Jan 25, 2019.

  1. Cantbreak100guy

    Cantbreak100guy Tele-Meister

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    I am trying to build this:
    Screenshot_20190122-150213_Chrome.jpg
    Screenshot_20190122-150149_Chrome.jpg

    I made a different layout in a smaller box. The tone switch doesn't work. I am hoping someone will point out where I went wrong.
    I believe the build above and the diagram differ. I went with the diagram. Also, I disconnected the 8ohm resistor. I don't need the impedance switch yet. I am well prepared to take all cheap shots about the graphics.:) 15484688344932928224251937499243.jpg 1548468969572526202062042939617.jpg
     
  2. sirbergersworth

    sirbergersworth Tele-Holic

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    I can’t see the 3rd and 4th attachments.


    Sent from my iPhone using Tapatalk
     
  3. sirbergersworth

    sirbergersworth Tele-Holic

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    I can’t see the 3rd and 4th attachments.


    Sent from my iPhone using Tapatalk
     
  4. warrent

    warrent Friend of Leo's

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    It's effectively a treble bypass switch. As long as you used an on/off/on switch it looks like it's wired fine.
    Depending on the wattage of the amp and the amount you are attenuating the switch might not make a difference.
     
  5. Cantbreak100guy

    Cantbreak100guy Tele-Meister

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    Warrent, good point. I was under the assumption it was a tone enhancement. It is an on/off/on switch. I wasn't sure the amp wattage would make a difference. I have a 5e3 clone, 15 watts. That may have been some helpful information. I really like the sound of it when it's distorted.
    I also wasn't sure the L-pad would be rated at 100w RMS or not. I figured the higher, the better. The good thing is that the L-pad is working as it should. The lack of tone change confused me.
    The funny thing is I have used the attenuator for a couple hours and I like the sound. Go figure.
    Thanks!
     
  6. 24 track

    24 track Doctor of Teleocity Silver Supporter

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    I dont know if any of this will help these are pics of a weber unit that a friend of mine asked me to mod ( this was one of weber's proto type units) it uses an 8 ohm Mas unit instead of the 8 ohm resister

    this schematic looks close to what you are building

    867e65f705f33102256f35a4f9f1771f.gif


    if you have the full schematic I would like to post it in the DIY post I have incase some one else wants to build one

    IMG_0871.JPG IMG_0872.JPG IMG_0873.JPG IMG_0874.JPG IMG_0875.JPG IMG_0876.JPG IMG_0877.JPG IMG_0878.JPG
     
  7. Cantbreak100guy

    Cantbreak100guy Tele-Meister

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    Wow! That looks legit. Thanks.
     
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  8. Cantbreak100guy

    Cantbreak100guy Tele-Meister

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    24 track: I wish I knew how that works.
     
  9. 24 track

    24 track Doctor of Teleocity Silver Supporter

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    you may be able to adapt you design to the schematic , hope this helps!
     
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  10. 24 track

    24 track Doctor of Teleocity Silver Supporter

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    weber used an 8ohm mass driver instead of the 8ohm resistor , but the design for the tone is just a little more elaborate than your design , basically the same circuit.
     
  11. 24 track

    24 track Doctor of Teleocity Silver Supporter

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    I dulled down this photo so you could see the controls -2.jpg
     
  12. warrent

    warrent Friend of Leo's

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    Whether you use your unit or the weber (which uses the speaker's voice coil to simulate some speaker reactance) the fact remain that they are both passive. Neither unit can add treble, they both use bypass caps to pass the existing high frequencies to the output. The rheostat will roll off some treble as you attenuate the signal. It's most noticeable with high wattage amps at full attenuation. With lower wattage amps and lower attenuation levels the roll off is very slight. The higher rated the rheostat the better.
    If anyone else wants to build this here's the link
    https://guitar.com/guides/diy-workshop/diy-workshop-build-your-own-attenuator/
     
  13. John How

    John How Tele-Meister

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    I’ve made a couple of those...my hearing is such that I couldn’t tell any difference with the different bypass caps...I still have them in the circuit but I can’t hear it...the attenuator works fine if you keep it rated for your wattage and don’t try to squeeze it down to bedroom level...it does quiet things down though...
     
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  14. 24 track

    24 track Doctor of Teleocity Silver Supporter

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    thanks Ill add it to my DIY thread!
     
  15. Cantbreak100guy

    Cantbreak100guy Tele-Meister

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    Nice! I do recall reading quickly through that section, maybe a little too quickly. Have you had a chance to look closely at the build there? I thought the 1 and 3 on the L-pad were incorrect based on the diagram. Let me know what you see. I wouldn't be surprised if I was wrong. Thanks!
     
  16. warrent

    warrent Friend of Leo's

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    In the circuit description the L pad is wired one way:
    Screen-Shot-2016-07-14-at-10.27.32.png
    but in the basic diagram its wired the same as the build.
    Screen-Shot-2016-07-14-at-10.28.31.png

    Pic-12-Stage-1-Hook-Up.png
     

    Attached Files:

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  17. rogb

    rogb Tele-Afflicted

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    This is what I built to use with my Marshall - it does the job OK. Airbrake improved (2).gif
     
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  18. Doctorx33

    Doctorx33 Tele-Afflicted

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    Warrent is correct about how the bright switches work. The caps allows higher frequencies to pass without attenuation, thereby making the amp seem brighter. I haven't done this in a while, but I think the higher value the cap is, the lower frequency threshold is extended.

    With different amps you may have to experiment until you find something you like. Use alligator clips to test until you find the right one. I've never used more than one, but that's personal preference.

    I've built a number of attenuators using that variable L-pad. It was originally designed for audio system use. For guitar use, I wouldn't use it with an amp over 30-35 watts rms, maybe a little more but only if you put a cooling fan in the enclosure. I've used it with my BF bandmaster but only dialed down a bit.
     
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