Silverface Champ to extension cab

Discussion in 'Amp Central Station' started by Riotic, Jul 23, 2020.

  1. Riotic

    Riotic NEW MEMBER!

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  2. BobbyZ

    BobbyZ Doctor of Teleocity

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    That should work, only thing I'd be worried about is it falling off while you're playing. Sometimes these things aren't the best quality. Like the ones you used to get at Radio Shack, they looked the part but were often made out if metal that didn't hold its shape and they got loose.
    What I've done is make my own adapter with a good RCA plug, some wire and a female phone jack. Also just switched the output jack in Champs from RCA to standard 1/4 inch phone jacks. That's probably the best bet for this and it's pretty easy to do when you're servicing the things.
     
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  3. tap4154

    tap4154 Doctor of Teleocity Ad Free Member

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    I recently bought that exact same adapter to use a small Weber attenuator sitting on top my Champ, and it seems to stay in pretty well. However if I was going to run it out to speaker cabinet I might do something about strain relief, so if you trip over the cable or something it won't yank out of the amp while you're playing.

    The pigtails I'm using from the amp to the attenuator are pretty lightweight, but a heavier cable plugged into that might be more prone to pull it out. As mentioned above if you're going to do this long-term, it would be best to have a quarter inch jack put in to replace the RCA jack on your amp. Also do make sure you use speaker cable, not a regular instrument cable to connect to the speaker cabinet.
     
    Last edited: Jul 23, 2020
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  4. uriah1

    uriah1 Telefied Gold Supporter

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    Isnt the champ output a weird ohm.
     
  5. corliss1

    corliss1 Friend of Leo's Platinum Supporter

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    Yup - 3.2, but that's close enough to 4 it doesn't matter.
     
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  6. xStonr

    xStonr Friend of Leo's Silver Supporter

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    That's the adapter to use. I had my SF Champ modded to the standard 1/4" so no issues if I want to connect a external cab.
     
  7. Tommy Biggs

    Tommy Biggs Friend of Leo's

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    I made a cable, just lopped off a 1/4" jack on a speaker cable and stuck an RCA on there. I always had it in the back of the champ. Sounded pretty good through a 4x12.
     
  8. BobbyZ

    BobbyZ Doctor of Teleocity

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    If you measure DC residence on a 4 ohm impedance speaker you get about 3.2 ohms.
    I've always wondered if someone way back when just put the dc resistance number on a speaker by mistake and started all this confusion. I've seen old speakers marked 3.2 and 4 ohms.
    You also see old British speakers marked 15 ohms. I'm not even going to try to guess why that came about. Maybe bad tea that day?
     
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  9. Ringo

    Ringo Poster Extraordinaire

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    In the past I just changed the phone jack out to a 1/4" jack, then put a 1/4" plug on the internal speaker, not hard to do and no worries about using adaptors. They sound great through a bigger speaker cabinet, try a 4x12 sometime, but kinda silly.
     
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  10. Riotic

    Riotic NEW MEMBER!

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    Awesome, thanks everyone! Does anybody have a link to a tutorial describing the process of switching out the RCA to 1/4"?
     
  11. wrathfuldeity

    wrathfuldeity Tele-Afflicted

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    Its easy, just open it up, look at the RCA, pay attention to which lug is the pin, desoder the RCA. Solder the 1/4 and tighten down to the chasis.

    Another option to use a pig tail (short spkr cord) to a shorting jack in the back panel. That way just use a skpr cord to plug to the correct ohm cab (or use a Weber Z matcher to match ohms)
     
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