Friday, 20 July 2012

Ross Compressor

As predicted! :o)

Although the layouts look different, this is extremely close to the Dyna Comp, I just rejigged things around to make the best use of space.  Unfortunately I needed an extra 3 rows, but c'est la vie. Here is a summary of the differences between the Ross Compressor and the Dyna Comp:

  • 1M resistor from Q1 base to vbias changed to 2 x 470K in series with a 1u cap from the junction of the two to ground.
  • 470K resistor from trimmer 2 to supply changed to 2 x 220K in series with a 1u cap from the junction of the two to ground.
  • Direct connection of Q1 collector to supply changed to 10K resistor with 1u cap from collector to ground.
  • Sustain pot 500K reverse log
  • Output pot 100K linear
  • There was also a 1u cap from vbias to ground but I'd already included a 100u in this position in the Dyna Comp as a more effective noise filter.





13 comments:

  1. Tag it!

    Buit and tested these two (this and Dyna) simultaneously. These both are really good compressors. I think i have Mr. Squishy clone for sale :)

    They have some minor differences soundwise, but generally i'm leaning more and more to Dyna, as it sounds (in my opinion) a bit more simpler. Both are just great. Fat and round, just like good compressor should be.

    I'm seriously considering about boxing these two in the same box: "The latest attraction from Motown! - Dyna & Ross" :D

    Great builds both of them. Definitely a keepers.

    Thanks a ton!
    +m

    ReplyDelete
  2. Boxing day's boxings part 2:
    http://mirosol.kapsi.fi/varasto/boxes/rcomp.JPG

    Ross comp in large box. For a friend.
    +m

    ReplyDelete
  3. hey I don't know if you guys take requests...but I'd really like to see a layout for the Ibanez CP9, Ross variant. Schem is here http://www.tonepad.com/project.asp?id=67

    ReplyDelete
    Replies
    1. or http://www.cruachan-audio.pwp.blueyonder.co.uk/schems/Ibanez_CP9.gif

      Delete
    2. Request noted, but for the moment i can't promise anything. If i was to draw it, i would use just single CA3080 to make it sane sizewise...
      +m

      Delete
  4. can i use lm13700 instead of ca3080 with this doughterboard? http://2.bp.blogspot.com/-P7jqffl_ejk/UHVUB0pXl-I/AAAAAAAAC-k/p2HwRW-52S0/s1600/LM13700+Daughterboard.png

    thanks

    ReplyDelete
  5. Yo! This layout looks nice, my board lack a compressor so i might give it a try! I'm a bassplayer so what mods can I do to make it more suitable for bass? I think there are other bassplayers out there in need of the same info :) Regards

    ReplyDelete
  6. I only have a 100k reverse log. Do you think it will work with that instead?
    /Martin

    ReplyDelete
  7. HI guys .
    I tried this one but it doesn't work and Just can't see why.
    Is there something important I might have missed?
    How can I test my circuit?

    ReplyDelete
  8. Hi, I have a question about the trimpot. I read in the Dyna Comp build that the trimpot is for adjusting the input level for noise.

    What should the trimpot initially be set to, 2k or some other value? Has anyone found an acceptable range for an initial setting?

    Thanks you.

    ReplyDelete
  9. I just finished one of these last month. I tried to use some of the keeley values and tantalums for the power filtering. Its actually a little noisier than my MXR Dyna Comp anyone have any ideas as too why. It should be quieter by nature as the ross compressors modded theirs to address the issue. HMMMM?

    ReplyDelete
  10. I just finished one of these last month. I tried to use some of the keeley values and tantalums for the power filtering. Its actually a little noisier than my MXR Dyna Comp anyone have any ideas as too why. It should be quieter by nature as the ross compressors modded theirs to address the issue. HMMMM?

    ReplyDelete