Who doesn't like 'treble bleed'?

Discussion in 'Guitars in General' started by mikenixon316, Jan 13, 2008.


  1. mikenixon316

    mikenixon316 Member

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    Why doesn't 'treble bleed' appear as standard on all volume pots?
    It seems odd to me that it should be considered normal to lose treble as the volume is turned down.
     
  2. Ed Alvarado

    Ed Alvarado Member

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    I just can't get along with the treble bleed caps and I guess I've played so many years without them that they just sound weird to me when the volume is turned down. It just sounds really thin to me.
     
  3. jzucker

    jzucker Supporting Member

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    i don't like it. Sounds thin to me.
     
  4. Pete Galati

    Pete Galati Member

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    When Fender was using 1meg pots in Telecasters, they had to add a .001uf treble bleed cap to make the volume rolloff sound right.

    Not everyone can make that sound good though. It's sort of an acquired skill. But in some situations, a 1meg Tele is like magic.

    When I put together an Esquire, I went with straightforward 250K pots to control the noise, and keep the sound fat.
     
  5. TimH

    TimH Member

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    I tried to have my new strat without it. Needed to install it.
     
  6. Tone_Terrific

    Tone_Terrific Member

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    You can't have both treble rolloff, which can be useful, and treble bypass, so one must choose.

    I like to tune the cap/resistor to create a near neutral effect as volume decreases and roll off top with the tone pot, if needed. I'll err on the side of thinness, but, I use a pedal a lot for volume control.
    So many means to the same end.
     
  7. Masa

    Masa Member

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    It doesn't work well with treble boosters in front of the amp, and I usually use a treble booster.
     
  8. eryque

    eryque Member

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    I honestly don't see how anyone can play a guitar with the volume tunred down without some sort of treble bypass. Most guitars turned down lower than about 8 sound horribly muddy to me, so bad that it's almost unusable.
     
  9. jzucker

    jzucker Supporting Member

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    So I guess SRV, Bonamass, Eric Johnson, clapton and Jimi sounded muddy to you?

    When you bypass the volume control with a cap, you let the thinner high frequencies go through which sounds shrill and unnatural to me.
     
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  10. jzucker

    jzucker Supporting Member

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    actually , I love the spot in SRV's Lenny where he turns the volume down and gets that really woody sound from having some high freq rolloff...
     
  11. FlackBase

    FlackBase Felonious Monkey Gold Supporting Member

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    I always snip that cap first thing if it's there. Sounds ratty to me.
     
  12. John Phillips

    John Phillips Member

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    It totally depends on the size of the cap and whether it has a resistor either in series or in parallel with it.

    You can have any effect from no detectable change compared to not having it, to extremely shrill and harsh when the volume control is turned down, and all points in between.

    Saying you don't like treble-pass caps (it's pass, not bleed, BTW) is about as sensible as saying you don't like single coil pickups because they all sound thin and weak.

    No offense intended.

    And yes, most treble-pass caps on guitars are overdone.
     
  13. Zero Point

    Zero Point Member

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    Treble bleed caps tend to cause havoc with some of my pedals. Especially the Sun Face.

    Besides, I like the tone loss when I roll back volume. Sounds thick and chunky.

    -ZP
     
  14. BBQLS1

    BBQLS1 Member

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    What's a good way to figure out what to use?
     
  15. StompBoxBlues

    StompBoxBlues Member

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    I would like to see what John says here too.

    Generally, I wonder if it wouldn't be smart to use a 7 band EQ to test. Turn the guitar down to where you want it to be, to identify the frequency you want to pass..or where the cutoff should be. Then one can find the formulas (in textbooks or on the net) and figure out which values you might need.

    But the basic configuration. I think there are three type,
    just capacitor, capacitor parallel with resistor, capacitor into resistor (series).

    It seems to me the least "intrusive" would be the series, since it would always present a minimum of resistance for the high pass, not letting it ever short out.

    The parallel, I think might be more gradual, but at some frequency point the capactor is going to be going very close or just plain shorted, so there will be no attenuation of those high frequencies from that point and above.

    As I said though, would really like to hear a knowledgeable take on this, how it is going to affect sound. I tried a parallel, don't recall the values offhand now, but on some strats it does let too much high freq through for me, so I need to adjust. wondering if I ought to try series cap->resistor...

    I also mentioned in a different thread not knowing where this "treble-bleed" idea came from, but I think generally a bleed is when
    some signal or part of a signal is shunted to ground, which is not what is happening here. Here we give an alternate path for
    certain frequencies to make it through the pot more or less "untouched".
     
  16. John Phillips

    John Phillips Member

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    Experimentation, unfortunately. There is no 'right' value or combination of values - it depends on the pickups, the pots, the guitar cable, and what you're plugged into, and this can affect the ideal values by up to a factor of ten.

    The one thing for sure is that the 'standard' .001uF cap with no resistor is WAY too much for anything other than a whole chain of curly cables and non-'true'-bypass mechanically-switched pedals.

    Reducing the cap value is not necessarily going to do the right thing though - it will reduce the amount of treble pass, but mostly by raising the cut-off frequency rather than reducing the amount - so you'll still get just as much very high end as before, and it may even sound more shrill and thin, if your amp/speakers will reproduce it well.

    Adding a resistor in series with the cap will reduce the amount of the effect and is much more useful.

    Adding a resistor in parallel with the cap also works, by letting more of the other frequencies past as well and making the treble seem less prominent - but it also changes the taper of the pot and the load on the pickup, so if you're perfectly happy with the volume taper now, you don't want to do this.


    The range of useful values for the cap is 100pF to 1000pF (.001uF), and for the resistor 50 to 500K (with 250K pots) or 100K to 1Meg (with 500K pots), both for series and parallel. Larger caps allow more upper-mids through and a little more treble, and larger resistors (in series) or smaller ones (in parallel) reduce the effectiveness of them.

    I would buy a few values of each - 100pF, 220pF, 470pF, 1000pF (and maybe 180pF, 330pF and 680pF if you can get them, but this isn't really necessary unless you need very fine tuning) caps, and 47K, 100K, 150K, 220K, 330K, 470K and possibly 1Meg resistors - they're only a few cents each, you can buy the whole lot for less than a dollar.


    If I had to pick a couple of good values that work 'on average', I'd go for 220pF in series with 150K on Fender-type single coils and 680pF in parallel with 220K on hot humbuckers, which also gives a nice 'clean up' effect as you roll down (if you want that). But if you're using very bright (short low-capacitance) cables, you may want smaller caps and/or larger resistors.


    Exactly. 'Bleed' is totally the wrong name for this circuit, and means signal leaking somewhere it shouldn't - either to ground (causing loss/'suck') or into another part of the circuit when you don't want it to (eg between channels on a channel-switching amp).

    This is a pass circuit, ie some frequencies are intentionally allowed through more than others.
     
  17. jzucker

    jzucker Supporting Member

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    Or like saying solid state amps sound bad.

    no offense intended. ;)
     
  18. greeny

    greeny Member

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    Yet again I totally agree with John.

    If done right I think it's brilliant IMO. The stock arrangement on my Suhr T is the best I've ever tried, Turning the volume down even to 2/3 has no dicernable effect tone at all.

    One way of experimenting is by using a variable resister. I did this on my Musicman Axis Supersport. I used the cap in series method (can't remember the value now) and adjusted the resistor to get the effect I wanted. It's not as good as on the Suhr but down to around 5 on the knob works really well.
     
  19. jzucker

    jzucker Supporting Member

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    One thing everyone is ignoring is that the eq rolloff you experience with the volume control is part of the tone that we all know and love, just like passive pickups, tubes and overdrive.

    Listen to Stevie Ray when he plays texas flood or Lenny and turns the volume control down. It's gorgeous.
     
  20. John Phillips

    John Phillips Member

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    That's true, but the bulk of his tone came from his Tube Screamers, which produce pretty much the same output tone even with rolled-off treble on the input ;).

    It's very much more of an issue if you're playing truly clean and don't have distortion (amp or pedal) to put back the upper harmonics that you lose.

    Some people like it, some don't. For those that do, no problem. For those that don't, there are ways to fix it...

    If we kept on doing things the same way as has always been done, we'd all still be sounding like Charlie Christian and Les Paul :). (Which is not a put-down as I'm sure you know, but there's so much more an electric guitar can do.)
     

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