Like Christmas Morning... Can't wait to open it up!

Discussion in 'Shock Brother's DIY Amps' started by ArcticWhite, Aug 4, 2019.

  1. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    Curb find.

    20190804_100919.jpg

    20190804_100926.jpg

    20190804_100934.jpg

    A pair of 12AX7A's, one 6AQ5A, and a 5Y3 rectifier. Neato.

    20190804_100938.jpg
     
    Last edited: Aug 5, 2019
  2. Toadtele

    Toadtele Tele-Holic

    Age:
    44
    Posts:
    807
    Joined:
    May 23, 2018
    Location:
    Idaho just the tip
    What do you mean curb find? Like take me I’m free? Or for sale. It’s cool for sure. But we need details
     
    ArcticWhite likes this.
  3. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    Free section on Craigslist.
     
  4. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    This thing is nuts.

    20190804_162143.jpg

    It's a reed organ with an electric fan, and the amplifier simply amplifies the reeds. So it's a loud accordion that you don't have to pump.
    Sonic heaven.
    Naaah...

    20190804_180104.jpg

    The reeds.

    20190804_163426.jpg



    20190804_162807.jpg

    The microphone. Naturally, I turned it on and using my best airport intercom voice, I paged my girlfriend - who was watering the front yard - to the nearest courtesy desk.
    It seems she lost a big bag of Marijuana and someone turned it in for her.
    The microphone tone is something like an AM radio through a vintage telephone. Lofi and I love it.


    20190804_163634.jpg

    The volume pedal simultaneously operates the amp volume, and opens the breather valve on the reed box.

    I hooked it up without the amp and it works fine. I may put a plug on the Reed and keyboard assembly, and turn it over to my neighbor's kid. He's four.

    20190804_162312.jpg

    The amp has a built-in vibrato.
    It's almost a guitar amp already.


    20190804_180749.jpg
     
    Last edited: Aug 4, 2019
    Mike SS, getbent, nojazzhere and 2 others like this.
  5. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    I need a schematic, bad.
    I don't want to gut it, just want to add an input jack, a tone stack and tweak it a bit.

    The Amp Chassis number is 157.10000
    An Internet search comes up empty..

    20190804_174428.jpg 20190804_174359.jpg 20190804_174445.jpg 20190804_174457.jpg
     
    Last edited: Aug 5, 2019
  6. VWAmTele

    VWAmTele Friend of Leo's

    Posts:
    3,172
    Joined:
    Feb 24, 2005
    Location:
    FL
    My family actually bought one of those for us for Christmas 1966. Loved it.
     
    ArcticWhite and 2 Headed Goat like this.
  7. printer2

    printer2 Poster Extraordinaire

    Posts:
    6,342
    Joined:
    May 24, 2010
    Location:
    Canada
  8. jimytheassassin

    jimytheassassin TDPRI Member

    Age:
    41
    Posts:
    83
    Joined:
    Apr 29, 2016
    Location:
    Oneida, NY
    Excellent score. You can take a look at a thread I made also. Silvertone reed organ with a 157.47210 amp inside. Like yours it was a curb find. Mine has a 6v6gt instead of the 6aq5, and a 12dw7 on the first stage. I’m pretty sure I’ve seen info on the one you have here. Just keep looking

    Silvertone 4721 Reed Organ Amp, With Real Pitch Shifting Vibrato
    https://r.tapatalk.com/shareLink?sh...l-Pitch-Shifting-Vibrato.103592/&share_type=t

    Sent from my iPhone using Tapatalk
     
  9. printer2

    printer2 Poster Extraordinaire

    Posts:
    6,342
    Joined:
    May 24, 2010
    Location:
    Canada
  10. sds1

    sds1 Tele-Afflicted

    Age:
    43
    Posts:
    1,077
    Joined:
    May 4, 2017
    Location:
    Orlando, FL, USA
    I am super happy your girl was able to recover her giant bag of weed.
     
  11. nojazzhere

    nojazzhere Poster Extraordinaire

    Age:
    67
    Posts:
    8,592
    Joined:
    Feb 3, 2017
    Location:
    Foat Wuth, Texas
    That looks like fun. I'd just play it as an organ and not "mess" with the amp, but that's just me.....it's yours to do with as you wish. ;)
     
  12. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    Craigslist is loaded with free organs.
    You could fill your house with them once a month. They are WORTHLESS.

    This one is basically a toy instrument built in 1966. It makes bad sounds. It is a piece of crap. It has ridiculous keyboard action.
    No one is listening to amplified reed organs. It is not a wurlitzer.

    Do you want to buy it? Send me 100 bucks, plus shipping and it's yours.
     
    sds1 likes this.
  13. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    No pitch shifting in this one, unfortunately. Looks like a completely different amp.
    Single 6AQ5 power tube. No varistors to be found .

    I may try to reverse engineer a schematic this evening.
     
    jimytheassassin likes this.
  14. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    Pics!?!?
     
  15. getbent

    getbent Telefied Ad Free Member

    Posts:
    36,913
    Joined:
    Mar 2, 2006
    Location:
    San Benito County, California
    hey, maybe you can use the reed thingy to make a talkbox.... rocky mtn way....
     
  16. RollingBender

    RollingBender Tele-Afflicted Vendor Member

    Posts:
    1,030
    Joined:
    May 14, 2011
    Location:
    SW Minnesota
    You have the right transformers tubes (close enough) and probably chassis and speaker to build this....

    AF6EE257-2DEA-4F89-BD93-17D52CC6CEE2.jpeg

    It’s actually a great sounding amp for guitar. Harmonica players love this one.
     
    ArcticWhite likes this.
  17. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
  18. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    Schematic
    I spent several evenings working out a reverse engineered schematic.
    Which was waaaay harder than I thought it would be.

    My first draft looked like a plate of spaghetti. Second draft looks like a layout drawn by a third grader, but it allowed me to make some sense of the thing. Third draft ain't too bad.

    20190817_071411.jpg

    Note that the first gain stage uses grid leak bias. Also that the tremolo works off of V1b only, which I think is an unusual position. I kept looking for a second tube to get involved.

    Is it odd to find there are three gain stages in a low powered toy organ?

    At some point, I may tear it all down and build the Kalamazoo 2 that Bender suggested. But for now, I'm curious about the super strange tone stack. One setting is for "Flute" and the other is 'Strings". Flute is bass heavy and muffled, while strings is trebly.

    Mods So Far
    I've pulled out the microphone and put in a jack with a 39k grid stopper, and a 1 Meg grid leak resistor because that's the biggest one I have right now.

    I bypassed the tone stack with a jumper, and the volume doubles and gets super crunchy.

    Fun project!
     
    symbiotic and RollingBender like this.
  19. ArcticWhite

    ArcticWhite Tele-Holic

    Posts:
    509
    Joined:
    Apr 14, 2009
    Location:
    Portland Oregon
    Questions for the board:

    Where do I put a jack for a tremolo footswitch?

    V1a is grid leak biased. Should I do the same for the next stage (V2a) ?
     
    Last edited: Aug 18, 2019
  20. printer2

    printer2 Poster Extraordinaire

    Posts:
    6,342
    Joined:
    May 24, 2010
    Location:
    Canada
    Sorry, haven't been around.

    [​IMG]
     
IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.


  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.