Cap on Rickenbacker bridge p/up?

Discussion in 'Pickups & Electronics [BG]' started by CROZ, Dec 13, 2005.

  1. Ran across this on the seymour duncan website.
    (look at #644)

    So those old ricks have a .0047 cap to cut bass on their bridge p/ups, they don't do that on the newer models I guess.

    Seymour seems to attribute at least part of Chris Squire's sound to it. I like his sound, I don't really want to copy it, but I definitely like it.

    This raises a few questions:

    The value of the capacitor is really small how much bass would this cut?

    This would be considered a highpass filter?

    Has anyone tried this on a Non-Rickenbacker bass? Seems like it would be an interesting thing to try out on a jazz bass and would be really easy to wire up with a toggle switch.
  2. luknfur


    Jan 14, 2004

    there have been numerous posts on caps and seems Smash's may be listed in the FAQ. There have been posts on Rics n caps in particular. Not up on Rics but my guess is they still have caps as they pride themselves on not changing their vintage stuff much. Smash also has a good shpiele on running jazz pups in series - which is how I've preferred them.

    More uncommon than not to use caps in passive basses. The SD Ric reference may have been regarding series more than the cap cause typically singles are ran parallel - and seems Rics are both singles. A cap variation of 10mfd will be quite noticeable. .047mfd is a standard bass cap value. To my knowledge, caps are the cheapest and easiest means of altering tone significantly. To my knowledge, a high pass filter is technically an active circuit that regulates only high frequencies not a passive circuit.
  3. luknfur


    Jan 14, 2004
  4. Yes that's a high pass filter (passive of course) and the cutoff frequency (-3 dB point) increases as you turn the voulme down. With the volume on 10, it's about 135 Hz (the formula is f = 1 / (2*PI*R*C) ).
  5. keb


    Mar 30, 2004
    Just to clarify, Rick still puts the .0047 bridge pickup cap in their C-series vintage-styled instruments, but the "regular" guitars and basses haven't had that cap since the late '80s.
  6. gamera


    Sep 20, 2004
    Gloucester, MA
    I don't get this. Isn't a high pass filter something that is on the tone control? This capacitor should have little to do with tone and everything to do with limiting output of the bridge pickup as it is on the volume of the bridge pickup. If you look closely you can see there are three capacitors. I'm not an electronics person so pardon my ignorance if this is what you said, but I thought a high pass filter was something to cut high frequencies. I'm not sure that is what this is.
  7. A high pass filter is a filter that lets high frequencies pass through it. The tone control in a passive bass or guitar is an adjustable low pass filter.

    The easiest way to understand how this works is to think of a capacitor as a resistor that changes with frequency: the resistance decreases as frequency increases, so at very high frequencies it behaves like a wire and at very low frequencies like an open circuit.

    Now, a passive tone control has the cap shunting the signal to ground, so at low frequencies it has no effect (open circuit) but high frequencies are short-circuited to ground, hence the low pass response.

    In the case of the Rick, that cap is in series with the signal, so it will let high frequencies through but show high resistance to low frequencies, cutting them off. Since the next component in the signal path is the volume control, which is a resistor to ground, the cap and pot form a voltage divider and that's why the cut-off frequency will vary with the position of the volume control.

  8. BassJunkie730


    Feb 3, 2005

    Way over priced. $700 for a vintage bass pickup that isn't a fender? (I know guitar pickups get up there) For that price the leads should at least come without duct tape on them. Sheesh!
  9. luknfur


    Jan 14, 2004
    Actually, I don't recall ever seeing a pair of vintage Fender J's approach $700 let alone a single. A lot of older bass pups are starting pull some bucks. TBird's for $300. And that's about the going rate on a Ric horseshoe, but not $700.

    There was a pair of 60's Gibson PAF's in Europe that brought the equivalent of $2500 BUT didn't meet the reserve, numerous bids for serious coin no less. Don't know what was up with that. They're usually around $700 a pair of so.
  10. Try and find one of those for cheap.....that's probably more rare than a vintage "Fender" pickup, and prettier too...