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Monday, November 2, 2015

Catalinbread RAH

This one's for those of you trying to nail some Jimmy Page tones. The RAH emulates the HiWatt heads Jimmy used live in the early days of Zeppelin. It uses only 3 MOSFET transistors, and features a 3-band EQ section. I'm going to shut up now so you can hear Andy from PGS put this thing through its paces.





29 comments:

  1. nice! :P

    but how high chance is it that the pcb is okey?
    loads of unverified projects here.

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    1. Stuff is unverified because people haven't built them. If you don't trust me, compare the layout to the schematic yourself.

      http://2.bp.blogspot.com/-bnlTjGc7DfM/T7zg-zA9OPI/AAAAAAAABW8/fXwHxSufzww/s1600/catalinbread+rah.PNG

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  2. I verified a bunch of David's layouts (more than 20, I think) and only one wasn't good, and the fix was pretty simple! BTW, I built one RAH (from my own layout) and it sounds pretty good, very dynamic and amp-like, but I expected it to have a bit more of gain. But still, sounds amazing and it works pretty good with other pedals pushing it.

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    1. E aí, xará!
      O que achou do Bass desse pedal? Esse é o maior motivo por querer construir um desses.

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    2. E aí, xará!
      O que achou do Bass desse pedal? Esse é o maior motivo por querer construir um desses.

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    3. Fala xará! Todos os controles respondem muito bem, e o pedal soa bastante amp like! recomendo!

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  3. E aí, xará!
    O que achou do Bass desse pedal? Esse é o maior motivo por querer construir um desses.
    this means:
    "Hey Bro! What do you think about the bass tone of this pedal? This is the greater reason that make me wish to build one"

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    1. Back in the day there weren't all that many bass specific amps. I'm sure this thing could sound great with bass, though some of the capacitor values might need to be adjusted/increased for better response of that frequency range.

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  4. It works as is, but to get to anywhere near unity with an amp the master has to be cranked on the pedal, should something be changed?

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  5. nevermind. After some research, this pedal is doing exactly what it should be doing.

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    1. Yeah, it's not a loud effect. It really comes alive though with a boost in front of it. Check out what Cody did with a Rah clone earlier this year.

      http://music.codydeschenes.com/?p=2844

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    2. Cool, Thanks!

      Should have the SD-1 verified in the next couple days.

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    3. has anyone tried playing with the resistor values for added gain? or even tried a b1m gain pot?

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  6. Is there any equivalent transistor, that can replace the bs170?

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    Replies
    1. Try the 2N7000. You'll have to rotated it 180º for the pinout, FYI

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    2. Thank you for supporting!

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  7. This comment has been removed by the author.

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  8. Hello, I´ve just finished the RAH but I have a problem.
    Before putting it in a enclosure with its 3pdt I tried it and it sounds, but with very, very little volume.
    You can´t almost hear it. The treble, mid and bass controls seem to work
    The master also acts, and it seems that the gain also, although the latter is not very clear, since, having so little volume, I do not appreciate it well.
    If someone could tell me where the fault may go I would appreciate it. I'm new in this DIYer world and I've tried everything I can think of.
    Please forgive my English. Part is mine and part of the translator, and I think neither of us are very good

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  9. Hi, sorry for the off topic but someone of good will could assemble the PCB layout of the Catalinbread WIIO? The wiring diagram is very similar to the RAH
    Here WIIO schemaics: http://2.bp.blogspot.com/-bnlTjGc7DfM/T7zg-zA9OPI/AAAAAAAABW8/fXwHxSufzww/s1600/catalinbread+rah.PNG
    Here a good sound example of Catlinbread WIIO: https://youtu.be/v4hmybejx44

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    1. Sorry, this is the right schematics for WIIO: http://revolutiondeux.blogspot.com/2012/05/catalinbread-wiio-rah.html

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  10. Hi, pls i dont have any of those 680n cap, which value can I substitute with? The nearest i have is 470n and 1uF film cap. Otherwise, is it possible to change a resistor value to reach the exact value of 680n. Thanks. Noob here lol

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    1. You could put 2, 330n caps in parallel, creating 660n which would be close enough. Otherwise I'd probably go with 470n.

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  11. Hello, I built this one a year ago, never worked well for my taste. It has a kind of lack of bright and the EQ pots never responded well.
    BUT a few days ago decided to open its guts again and tweak some values, and changed the input cap to 1.2 nF and Bass pot to A250K.
    Surprisingly, the EQ started to work fine, MID and TREBLE now react to their positions, and the BASS can get either flat or full of body and everything in between.
    I was thinking of change the 680 nF cap for a 470 nF like the WIIO but I'm gonna give it a chance.

    Side comment: try this one as preamp directly to loop return of your amp and it kicks asses.

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    1. Hi, is there any tweaks you did or it is only for the input cap and the Bass pot? How changing the 680nF cap to 470nF will affect the sound of the pedal? Ty

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    2. It will probably get a tiny bit brighter. I can tell you because I have even removed that capacitor completely - the result is just a bit more gain and brightness. Decreasing the value of the input cap will decrease bass (I wouldn't recommend this for this pedal, since it can be quite bright, IMO/IME).

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  12. Since I made a partslist anyways, I though I might post it here for you all:
    RAH Partslist:
    A250K (Master)
    A500K (Bass)
    B100K (Mid)
    B250K (Treble)
    B500K (Gain)
    Transistors 1-3: BS170
    Diode D1: 1N400X
    Z1-3: 9.1v Zenner
    -------------------
    Resistors:
    130Ohm
    1K
    10K x2
    100K x3
    1M x3
    3.3K x6
    22K x2
    62K
    220K x2
    ----------------
    Capacitors:
    47pf
    220pf
    1nF x2
    2.2nF x2
    3.3nF
    47nF x3
    100nF x2
    220nF
    680nF
    ----------
    10uF x2
    22uF x2
    47uF
    --------------

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