Modding Pedals 101

[soupbone]

Hi folks.So,I came up with this mod for the infamous Boss DS-1.I sort of know what's going on,but i need some further explanation.Here's the mod;

R6-150k
R9-10 ohm
R13-1k
R14-10k
R16-5k pot (midrange knob)
R17-15k
C2-.022
C5-1uf
C8-1uf
D4-D5-Taken out
So,I kind of know about some of the parts,Like the R13 which is one of the distortion resistors.(There may be more?)I took it down to 1k because of the loss of drive from taking out the diodes.Any further explanation of what's going on would be much appreciated!

[soupbone]

Hi folks.So,I came up with this mod for the infamous Boss DS-1.I sort of know what's going on,but i need some further explanation.Here's the mod;

R6-150k
R9-10 ohm
R13-1k
R14-10k
R16-5k pot (midrange knob)
R17-15k
C2-.022
C5-1uf
C8-1uf
D4-D5-Taken out
So,I kind of know about some of the parts,Like the R13 which is one of the distortion resistors.(There may be more?)I took it down to 1k because of the loss of drive from taking out the diodes.Any further explanation of what's going on would be much appreciated!

Yello?

[.Mike]

Yello.

If you want help with a specific schematic, it is probably in your best interest to link to the schematic.

Even though it is a very common circuit, there are many different schematics circulating, and many of those use different part numbers.

I doubt you'll find many people willing to search around the internet in hopes that the DS-1 schematic they find is the one you meant to reference.



Mike

[soupbone]

Yello.

If you want help with a specific schematic, it is probably in your best interest to link to the schematic.

Even though it is a very common circuit, there are many different schematics circulating, and many of those use different part numbers.

I doubt you'll find many people willing to search around the internet in hopes that the DS-1 schematic they find is the one you meant to reference.



Mike

This is the best one I've found by Brett Miller(5 Thumbs)and Muhammad Iqbal; http://www.diystompboxes.com/DIYFiles/up/Build_Your_Own_DS-1_Distortion.pdf  The only difference in the schematic i believe is the ic.(New ones have the NJM3404AL Chip.)

[petemoore]

R6-150k...base bias resistor, part of the resistive divider/base bias resistors, should lift the base voltage a touch.
R9-10 ohm...Emitter resistor, bumps the gain up...brings the E closer to Gnd.
R13-1k ...has to do with the opamp gain/frequency 'string' there...apply the R/C formula or try it and see.
R14-10k...another R/C position, smaller R in the signal path = reduced losses
R16-5k pot (midrange knob]...perhaps 5k + 3k3 [?] stop resistor so the range = 3k3 - 8k3 adjustable resistance there [this would cover the original fixed value of 6k8.
R17-15k...messes with the tone control, try the 15k there, and use a jumper resistor across it to try the sound of smaller values
C2-.022...was .o47uf, series in signal path...smaller values cut more bass
C5-1uf...another signal path capacitor
C8-1uf...again a SP Capacitor, personal voicing preferences apply to these.
D4-D5-Taken out...these are the clipping diodes, another great place to 'mess with', by raising the threshold of the diodes [taken out makes it more of a DB-1 [dirty boost I guess] because no hard clipping without them. Try different values here for sure for big differences in output level/how hard the signal is clipped/distorted.

[petemoore]

  The 'voicing caps' mentioned..in series with the signal path..cut bass content, early/middlin'/ and late in the circuit, for less bass getting into the diodes, put smaller value[s before the clipping section], to clip a wider frequency band, allow the bass into the circuit through to the diodes, then cut it later...ie 'hack' out some bass early, or 'sprinkle-voice' the circtuit [it starts off as 'sprinkle voiced'...all the voicing caps throughout the circuit are valued so each does some [or more] of the voicing...across the schematic. Putting 1 'very small' cap at the intput [or before] lets you know what 'mosquito-like' input tends to sound like when clipped/distorted // OTOH, letting the bass 'get in to be clipped, then cutting it after all the signal has been clipped [bass carries lots of ''uumph'' so maybe you like that to get clipped...then trimmed]...
   All in the eyes and ears of the beholder.
  The value changes in the tone section/general voicing capacitors [and R/C values] alter the frequency response around where they are and throughout the rest of the circuit.
   Messing with the diode clipping thresholds makes a whole different distorter from a circuit, more output [the diodes are high threshold configuration and allow more signal through] or harder clipped signal [less output]...the diodes only let 'X' voltage through, so any peaks or signal above 'X' level is 'lopped off' forever [unless a post-boost recovery is added].

[soupbone]

R6-150k...base bias resistor, part of the resistive divider/base bias resistors, should lift the base voltage a touch.
R9-10 ohm...Emitter resistor, bumps the gain up...brings the E closer to Gnd.
R13-1k ...has to do with the opamp gain/frequency 'string' there...apply the R/C formula or try it and see.
R14-10k...another R/C position, smaller R in the signal path = reduced losses
R16-5k pot (midrange knob]...perhaps 5k + 3k3 [?] stop resistor so the range = 3k3 - 8k3 adjustable resistance there [this would cover the original fixed value of 6k8.
R17-15k...messes with the tone control, try the 15k there, and use a jumper resistor across it to try the sound of smaller values
C2-.022...was .o47uf, series in signal path...smaller values cut more bass
C5-1uf...another signal path capacitor
C8-1uf...again a SP Capacitor, personal voicing preferences apply to these.
D4-D5-Taken out...these are the clipping diodes, another great place to 'mess with', by raising the threshold of the diodes [taken out makes it more of a DB-1 [dirty boost I guess] because no hard clipping without them. Try different values here for sure for big differences in output level/how hard the signal is clipped/distorted.

Wow!Cool!That's some very in-depth analysis!Big thanks!