Results 1 to 3 of 3

Thread: Tone caps for EMG

  1. #1
    New Member
    Join Date
    Sep 2014
    Posts
    4
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0

    Question Tone caps for EMG

    I have a pair of EMG HA pickups in my Ibanez. Since I rarely if ever used the tone knob, and there's no room to install any of the active tone systems in the guitar, I was wondering if I could just change the stock .1u capacitor to something smaller for a certain effect. What I would like to achieve is a roll off at around 2 - 2.5kHz, just below the resonance of the pickup (listed at 3.75kHz), so I could have another usable tone at hand. Is there any way to calculate this? Also, I guess in the case of EMGs, the tone circuit doesn't form a resonant peak when rolled off fully, because it doesn't interact with the inductance of the pickup, so it's simply a first order low pass filter. Am I right about that?

    Thanks!

    0 Not allowed! Not allowed!

  2. #2
    Supporting Member
    Join Date
    Dec 2009
    Location
    UK
    Posts
    3,437
    Thumbs Up/Down
    Received: 178/0
    Given: 20/0
    Rep Power
    13
    The EMG pickup 'sees' its own internal preamp (just a single op-amp configured as a differential amplifier) and the tone/volume controls are buffered from the pickup inductance and self-capacitance. The resonant frequency isn't therefore affected in the same way as a passive pickup by tone control loading or cable capacitance, so isn't useful in calculating tone control values.

    The way I would approach this is to use a couple of short clip-leads and try different caps until I got the one I liked best. You could model the tone stack and output impedance of the amp (10k ohm) in PSpice and do an AC sweep analysis to visualise what's happening, but in the end it comes down to your hearing and perception of the sound. I've found that changes to EMG caps need to be fairly drastic to make meaningful/useful differences to tone.

    0 Not allowed! Not allowed!

  3. #3
    New Member
    Join Date
    Sep 2014
    Posts
    4
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    Thank you Mick. I guess I can't get away without trying a couple of caps (just to return to the original value and screw the whole thing, lol).

    0 Not allowed! Not allowed!

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Tone Caps
    By trickster1234 in forum Music Electronics
    Replies: 2
    Last Post: 10-21-2012, 03:27 AM
  2. Tone caps ?
    By gtrplayr1976 in forum Guitar Tech
    Replies: 8
    Last Post: 01-06-2011, 06:05 PM
  3. EMG tone cap
    By Brad1 in forum Guitar Tech
    Replies: 1
    Last Post: 01-01-2009, 09:06 PM
  4. need tone caps
    By mark enger in forum Guitar Tech
    Replies: 0
    Last Post: 10-27-2008, 12:43 AM
  5. filter caps and tone
    By daz in forum Theory & Design
    Replies: 8
    Last Post: 09-23-2008, 02:09 AM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •