Friday, 4 January 2013

2 Channel Mixer

I needed something like this myself, so why not share. I've been thinking about building a console for our keyboardist. She has this amazing wooden 70's Casiotone that i dugged up from trash and it worked. It's default sounds are pretty bad, but using the organ sound and putting it through Skreddy Lunar Module Deluxe makes it nothing less than a perfect punkrock organ. She also has MicroKorg XL in her setup, so i thought i'd build a two channel active mixer for the organ (with fuzz) and synth - then take that to active DI, so she'll have just one balanced output and total volume control from one console. This is snipped out from GGG's 4 channel mixer schematic. If anyone really needs more channels to this, i could draw one with more...

Here's the revised version of the two channel version of this mixer. One resistor change will add more output level...


Posted by at 06:21
Tags: , , ,

48 comments:

  1. NoNE4 January 2013 at 08:07

    Yeah thanks Miro and please a 4 channel version !

    François

    ReplyDelete
  2. Σταύρος4 January 2013 at 10:05

    I’m definitely going to try that! I’ve been looking for something like that for a while but, finally, with an IC.
    Question: As I understand this mixes the effect with your dry signal, so there are no losses if let’s say the second effect is turned off and non true bypass right?

    ReplyDelete
    Replies
    1. mirosol4 January 2013 at 10:22

      If you're going to use this for blending the clean with effect chain, then you would need some sort of signal splitter. Preferably, you should go for one of these: http://tagboardeffects.blogspot.fi/2012/02/split-n-blend.html
      http://tagboardeffects.blogspot.fi/2012/01/mini-blend-jfet.html
      http://tagboardeffects.blogspot.fi/2010/11/jfet-parallel-looper.html
      http://tagboardeffects.blogspot.fi/2010/07/guitar-and-bass-paralooper.html

      You can find the documentation from ggg:
      https://www.generalguitargadgets.com/projects/15-boostersrouters/68-mini-mixer-project
      +m

      Delete
    2. Σταύρος4 January 2013 at 14:37

      Of course I was planning to make all of these, one each time and check, but then you came out with this layout and thought to start with this one. Anyway I think I will try all of them anyway and see what works better. Thanks

      Delete
  3. LettucePrey4 January 2013 at 13:26

    Hello Miro. I've been trying to come up with a way to run my Tech21 Blonde character pedal into headphones for late night practicing but the output of the Tech21 is only heard in one ear and has a very weak signal. Do you think this mixer with a stereo output jack would be the ticket? The signal would go:

    guitar --> pedalboard --> Tech21 Character Pedal --> This mixer --> Headphones

    ReplyDelete
    Replies
    1. mirosol4 January 2013 at 13:42

      So you built it?

      It is not a headphone amplifier - just a summing amplifier with two inputs and one output with variable input levels for both channels. So if you are feeding a line signal from a pedal to it - it comes out as line signal and in mono.

      +m

      Delete
    2. mirosol4 January 2013 at 13:43

      You'll still need an amplifier. You could build yourself this:
      http://tagboardeffects.blogspot.fi/2012/04/noisy-cricket-mkii.html

      It has option for headphone out.
      +m

      Delete
    3. mirosol5 January 2013 at 09:01

      Calling PaulR!

      So you built this mixer and it works as intended?
      +m

      Delete
  4. kambob4 January 2013 at 13:42

    how bout a vero for a good active DI box?

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    Replies
    1. mirosol4 January 2013 at 13:48

      I've drawn one, but i won't publish it before i can verify it myself (not too simple circuit) - I'm waiting for 22µ non-polar caps to arrive. Once i've verified it, it will be published.

      Just a heads up: You'll probably want to order a few 22µ non-polar caps with voltage rating at least 35V and some 24V zeners :)
      +m

      Delete
    2. kod2nd25 February 2013 at 06:57

      +1 on the Active DI

      Delete
  5. mirosol4 January 2013 at 13:53

    I'll draw a headphone amp tonight :)
    +m

    ReplyDelete
  6. Unknown9 January 2013 at 14:34

    I would like to use this on my pedal board with a EHX superego. I use effects in the loop of the superego but I dont want the effected sound fed into the distortion after the superego. my plan would be to run the guitar into the superego, connect from the super ego send jack to a chorus and delay and then instead of using the return jack on the superego use this 2 channel mixer. the inputs of the mixer will be the effected superego synth tones and the guitar signal that has been distorted after passing through the superego's output. will this work? Can i delete the volume controls on the mixer and use it as an active combiner? The superego has separate dry and effect level controls.

    Thanks,
    Scot-

    ReplyDelete
  7. Traductions Mathieu Tremblay15 October 2013 at 17:02

    What's D1? Also, could I use this with say, a fuzz circuit to have two separate controls for clean and effect in a single pedal?

    ReplyDelete
  8. Derek25 October 2013 at 23:57

    Yes, I'd love to know what D1 is!

    ReplyDelete
    Replies
    1. mirosol26 October 2013 at 00:29

      A diode. In this case, a polarity protection diode in series with the supply. 1N5817.
      +m

      Delete
  9. Unknown14 December 2013 at 01:51

    I build this mixer yesterday.
    but it's volume a little decrease more than bypass.
    how can i resolve it?

    ReplyDelete
  10. nandychu9 January 2014 at 10:12

    Hi, can i use 10k linear instead log?

    Thanks!

    ReplyDelete
  11. Paul18 February 2014 at 02:33

    Thanks for the layout! I built it up tonight (unboxed so far) and it works well, but there's a slight, but noticeable hiss. I swapped the TL072 for an NE5532 and that seemed to help somewhat (to my hopeful ears, anyway). The only other substitution I made was a 1n4001 for D1, as it's just a polarity protection diode and shouldn't matter anyway, right?

    ReplyDelete
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    1. Paul1 March 2014 at 23:31

      I ended up solving my hiss issue by socketing the 10K resistor and increasing it slightly to the point where the overall output was slightly lower, but still loud enough for lots of gain in the 2 channels. Thanks!

      Delete
    2. mirosol6 April 2014 at 19:07

      I've missed your posts completely. I'll tag the layout asap. Cheers Paul!

      Finished my own build of this one today. Tried the box out with Ibanez SC10 which has inverting stereo output. The sound gets fun and weird when you mix the non-inverted and inverted together at nearly the same level. Fun thing.
      +m

      Delete
    3. Mikka30 May 2016 at 23:25

      Hi Paul, I have a hiss issue with this mixer as well, I would like to ask you where in the scheme/pcb did you put that 10k resistor? I am using NE5532.Thank you very much.

      Delete
    4. Mikka30 May 2016 at 23:26

      Hi Paul, I have a hiss issue with this mixer as well, I would like to ask you where in the scheme/pcb did you put that 10k resistor? I am using NE5532.Thank you very much.

      Delete
  12. Unknown8 May 2014 at 17:25

    I play bass and synth, and would like to be able to use just my bass amp for the two. Would this build work in that situation

    ReplyDelete
    Replies
    1. mirosol8 May 2014 at 17:33

      Yes.
      However. You should take into account that your synth is giving out line level signal, while your bass is giving out only what it can with its pickups. This means that you'll want to lower the synth's output level before it's sent to the mixer.
      +m

      Delete
    2. Mon30 August 2015 at 12:31

      Hi. Does that mean that this mixer is for instrument level signals? If I wanted to plug it in to a PA mixer, I will still need an active DI, correct? :)

      Delete
  13. Unknown8 May 2014 at 18:24

    awesome thanks, it will actual be some midid foot pedals controlling annimoog so it should be pretty easy getting the volume down.

    ReplyDelete
  14. Unknown21 January 2015 at 15:38

    Thank you for this fantastic layout !
    Could anyone help me ?
    Id like to add a little mod : 2 outputs and a switch.
    the switch could toggle between position 1 ( normal layout ; both channels 1 and 2 goes to output 1) and position 2 ( channel 1 to output 1 , channel 2 to output 2)...
    could it be possible ?
    Thank you anyway !!

    ReplyDelete
    Replies
    1. Unknown21 January 2015 at 15:49

      And a question too , do this mixer work on 12v alim ?
      Thanks again :)

      Delete
    2. Unknown27 January 2015 at 07:13

      Nobody ?

      Delete
    3. mirosol27 January 2015 at 09:07

      Works fine with 12V.

      But that other thing.. Not so simple. The circuit is 2 channel mixer, so you'd need a splitter circuit for the second channel before the mixer input and then figure out the switching for the ouputs. And even then you'd probably run into impedance mismatch on ins and outs.
      +m

      Delete
    4. Unknown27 January 2015 at 15:16

      Thank you !

      Delete
    5. FrogT17 June 2017 at 11:19

      argh I need exactly the same thing! I've got 2 channels with their own passive tonestack, then a JFET buffer each, then this mixer; that's what I plan to do. So impedance mismatch??

      Delete
  15. Sonicguitars5 February 2015 at 20:30

    Hi Mirosol, I want to use it to play two acoustic guitars (with piezo preamp) in one acoustic guitar amp, could work also with high piezo impedance?
    Paolo

    ReplyDelete
  16. Unknown15 February 2015 at 11:04

    Hello,
    I'd like to add a A/B F-switch on it ,
    from this layout : http://www.generalguitargadgets.com/pdf/ggg_sw_ab_lo.pdf

    correct me if I'm wrong, but I just need to connect the Input 1 (Out A on the layout) TIP to Channel 1 Input, and Input 2 (Out B) TIP to Channel 2 Input ?

    Should I invert the Stereo Jack they've named Input (Out for me) to MY Input 1 (Out A) -with the wiring for the battery- ?

    Thank you for your help,
    sorry for my bad english, I'm french ;)
    C.

    ReplyDelete
    Replies
    1. Unknown16 February 2015 at 19:08

      This comment has been removed by the author.

      Delete
    2. Unknown16 February 2015 at 20:38

      actually, I just add a 3 pdt F-S,
      1 - Input 1
      2 - 2 => 5 bridged
      3 - Input 2
      4 - to Channel 1
      6 - to Channel 2
      7 - Led 1
      8 - Grnd
      9 - Led 2

      is it correct ?
      Thanks again ;)

      Delete
  17. Carpe DM11 July 2015 at 05:00

    I have some phase issues with this. Are there any quick fixes?

    ReplyDelete
  18. Carpe DM11 July 2015 at 05:00

    I have some phase issues with this. Are there any quick fixes?

    ReplyDelete
  19. ari2 August 2015 at 01:42

    Hi! I have build this mixer and I get the sound too low. Someone same thing happens?
    Thanks.

    ReplyDelete
  20. Mon30 August 2015 at 12:34

    Please correct me if I'm wrong here, can I put 2 of this 2-channel mixer (one for left and 1 for right) then it'd become a stereo mixer? The pots would be dual ganged too.

    ReplyDelete
  21. Unknown18 December 2016 at 01:23

    I want to build a Pedal with two Inputs, combining the Signal of two Keyboards, couldn't I just connect the signal paths and both run them into my (flanger) circuit? I dont need to alter the input levels...

    ReplyDelete
  22. Unknown4 August 2017 at 16:29

    Can I build it without the two 10 log pots? Because I allready have an enclosure ready. Is the signal at maximum volume input and output volume without the 10 logs? Thanks for the help. Leon

    ReplyDelete
  23. Unknown19 August 2017 at 13:52

    I finished the mixer. Build It without the pots. Changed the 10K to a 100K because the output was to much amplified. I have the hiss issue to. Anyone a idea how to silence the mixer?? I put a picture of my build on photobucket.

    http://photobucket.com/gallery/user/LeonStratman11/media/bWVkaWFJZDoxOTY3MjkwNDA=/?ref=1

    ReplyDelete
  24. Werther Ellerbrock7 April 2020 at 06:23

    The 22μF capacitor is mixed up with a 2.2μF capacitor. As per the original General Guitar Gadets schematic: 22μF + should be connected to pin 8 of the IC (not 5 as per this layout), and 2.2μF + should be connected to pin 5 of the IC (not pin 8 as per this layout). Wasn't this supposed to be verified? http://www.generalguitargadgets.com/pdf/ggg_mixer_sc.pdf

    ReplyDelete
  25. Anonymous11 August 2020 at 15:41

    Greetings, TagboardFX community. I would like to respectfully point out that Werther's comment is correct. 22μF + should be connected to pin 8 of the IC (not 5 as per this layout), and 2.2μF + should be connected to pin 5 of the IC (not pin 8 as per this layout). I built this layout several times, and had the dreaded hiss each and every time. So, after reading Werther's comment, I went over the GGG schematic and created a perfboard layout of my own. It works perfectly, no hiss. TL072 works great, no need to sub in the NE5532, I reckon. Just wanted to add this information so that other folks don't waste time running into the same problems the rest of us did.

    ReplyDelete
    Replies
    1. Martin30 May 2021 at 16:17

      I've done the capacitors adjustments and the circuit is working without hiss. But the overal output sounds dull, especially channel 1 sounds like there is a hi-cut on it. Any idea what can be wrong?

      Delete
  26. kyle50005 June 2021 at 11:22

    how to wire this in 3pdt switch?

    ReplyDelete

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