is this a common problem?

[blanik]

i've experimented often with boosters and distortions, everytime i put a booster before the distortion is doesn't boos the volume but make more distortion, it sound cool and useful at low volume but never was able to make it sound good live (would always sound muddy at high volume) now i've tried with the booster after and it great but if the distortion is too loud the sound will cut out out when i engage the booster, then as the notes decay the sound will come back, like a gated effect, is there a way to make the booster take a high volume with dignity? 

[Mark Hammer]

I'm not sure from what you wrote whether this is something that happens only when you turn the booster on or whether it happens each time you hit a chord hard after the booster is turned on.  Those two outcomes will have different origins.

As for booster before distortion, the lack of any volume boost is a function of the amount of headroom in the distortion itself.  Yuo cannot exceed that headroom, so if you have it at maximum distortion, adding more gain to the input will not be able to push the signal past that ceiling.  Of course, if you have more headroom, then that boost will be audible.

Depending on the distortion in question, it may be the case that more recovery gain can be obtained from the existing circuit by simply changing a component value.  In which case, you could produce the distortion+boost function by simply altering the output level of the distortion effect.

[blanik]

hi mark, it's actually a klon Centaur (it's running on a charge pump so it's go a lot of headroom) into a SHO, the SHO before any distortion sounds good at low volume but cranked, it sounds too mushy on the low end (farts out) so i tried the SHO after the KC and it sounded great but if the level of the KC is too high into the SHO the sound cuts and comes back like a gated effect of some sort... the SHO has a pretty high headroom too so i was wondering what made the sound cut out...

[petemoore]

the SHO has a pretty high headroom too so i was wondering what made the sound cut out...
  I get the idea your'e running an 18v Klon, sorta cranked, into a Sho @9v.
  Turning down the Klon volume, and turning up the Sho volume...works ?
  I get the samilar thing with a Mu Amp [or any booster at 9v, which is getting a very hot input], the character of the sound changes in many ways, including 'partial cut out' or frequency specific gain drops, other non-linearities I think are associated with signal swing nearing the PS potential.
  The Mu Amps [Minibooster] input gain control...allows me to run the distortion kind of hot, push but not slam the Mu amp gain stage...I voltage divide the input signal.
  So a simple twist to decrease the pregain and increase the end volume [literally the last control on my pedalboard is the Minibooster volume], allows plenty of output, but the sound stays more 'intact'.
  All that said...hope this is the problem or that this helps, pre-gain can be tried out by turning the klon volume down and compensating with the sho output setting.

[Paul Perry (Frostwave)]

the character of the sound changes in many ways, including 'partial cut out' or frequency specific gain drops, other non-linearities I think are associated with signal swing nearing the PS potential.

I expect that - depending on design - running a VERY hot signal from a box with +15 supply to one with +9 supply, could exceed the allowed input conditions on the first op amp in the second box. Causing the op amp to rapidly reverse output voltage, or to hang for a while.

[JDoyle]

What Paul said...

If you take a 15Vp-p signal from the Klon and send that into an SHO which has PS rails of 9V, you are setting up a situation whereby the gate of the SHO's MOSFET can now reach ABOVE V+, and therefore it's drain. Any caps between the input and the gate of the MOSFET will be charged to the input level and until they 'come back down to earth' will cause all kinds of issues, or at least completely change the operation.

Also - a larger signal also means that, for the same frequency, an amplifier will have to have a faster slew rate to reproduce it. This means that while the SHO may be more than adequate reproducing every guitar frequency for a 7Vp-p signal, when fed a 15Vp-p signal, even though it is clipping the rails badly, and therefore STILL only able to push 7Vp-p out when fed the signal from the Klon, the SLOPE of the 'sides' of the signal, the rate of voltage change, has increased because of the increased signal size, and that is when the SHOs slew rate is inadequate. When an amplifier slews, all it can do is try to catch up to the voltage where it 'should' be, and it does this at whatever speed the compensation cap (or capacitance from Drain to Gate in the case of the SHO) allows it to - and WHEN it is doing this, nothing else gets through. And because the fastest and largest signals from a guitar are those that appear on transients/initial attack, the rest of the tone of that note gets 'blurred' as the amplifier is unable to reproduce any of it until it 'catches up' with the signal that caused it to slew limit...

Anyway...a couple of possible reasons...

Regards,

Jay Doyle

[blanik]

What Paul said...

If you take a 15Vp-p signal from the Klon and send that into an SHO which has PS rails of 9V, you are setting up a situation whereby the gate of the SHO's MOSFET can now reach ABOVE V+, and therefore it's drain. Any caps between the input and the gate of the MOSFET will be charged to the input level and until they 'come back down to earth' will cause all kinds of issues, or at least completely change the operation.

Also - a larger signal also means that, for the same frequency, an amplifier will have to have a faster slew rate to reproduce it. This means that while the SHO may be more than adequate reproducing every guitar frequency for a 7Vp-p signal, when fed a 15Vp-p signal, even though it is clipping the rails badly, and therefore STILL only able to push 7Vp-p out when fed the signal from the Klon, the SLOPE of the 'sides' of the signal, the rate of voltage change, has increased because of the increased signal size, and that is when the SHOs slew rate is inadequate. When an amplifier slews, all it can do is try to catch up to the voltage where it 'should' be, and it does this at whatever speed the compensation cap (or capacitance from Drain to Gate in the case of the SHO) allows it to - and WHEN it is doing this, nothing else gets through. And because the fastest and largest signals from a guitar are those that appear on transients/initial attack, the rest of the tone of that note gets 'blurred' as the amplifier is unable to reproduce any of it until it 'catches up' with the signal that caused it to slew limit...

Anyway...a couple of possible reasons...

Regards,

Jay Doyle

thanks, that's perfectly clear! i'll try another way, a second volume pot with a switch to select vol 1 or vol 2...  with 15V headroom it'll do the job...!

[DougH]

Kids- It's called compression.

[JDoyle]

Kids- It's called compression.

What would be the required compression ratio need to cut out a signal? 

I see your point Doug, but as Blanik posted, slamming the SHO causes the signal to cut out; something other than compression is going on...

Jay

[Mark Hammer]

The KC is really designed to be in front of an amplifier, specifically a tube amplifier.  I don't doubt that it can sound good in other contexts, but that is the intent.  The planning around use with a tube amp typically means seeing a 68k input resistor in series with the first tube.  Is that set of circumstances replicated with the SHO, and if not, does that influence the interaction of these two pedals?

[DougH]

Oh, he said cut out... Somehow I missed that part.

People post about "why doesn't my fuzz box get louder when I put a booster in front of it" kind of stuff and I thought this was one of those.

Never mind...

[Jered]

  What happens if you run the Klon at 9 V. Just curious.