PRODUCT REVIEW
quencies are being filtered. With the current values you will find it’s
filtering everything above 7k, which helps to smooth things out a
little bit. If it’s too bright, replace R14 with a resistor valued at 3.3k,
allowing more highs to be filtered out, or try a 4.7k resistor to filter
out everything above 3.3kHz.
After traveling through the diodes and the capacitor, the signal
goes through a Big Muff π inspired tone control. There are many
things we can do to manipulate the tone here, and a great resource
is the Duncan Tone Stack calculator, available at duncanamps.
com/tsc/. Experiment with different values to find the tone you’re
looking for. In the stock version of the pedal, the tone is a bit
“scooped” meaning that there is little mid frequencies allowed
through making the tone a little “thin” sounding. We can change
that quite easily however. Check out the suggested changes in the
charts below to get a warmer tone, a scooped mid tone or simply
less highs.
After the tone control the signal travels through the level control
and then out through R18, which is a 10k resistor, and then on to
Q7, which is the other side of the JFET switching circuit. In its on
state, it goes past Q7, through C13 – which is a .047µF capacitor
– through yet another output buffer and then a resistor, a capacitor
and finally through the output.
Let’s look at some modifications that will have your DS- 1 doing your
bidding in no time.
Classic JCM-type Marshall Tones:
LOCATION CHANGE TO:
C3 .033
R C C13 37 1..0 053 3k3 3
C R127 1µ5Fk
D C42 1N µF4148 Connected in Series to another 1N4148
D C543
1.0N343010418ConnectedinSeriestoanother1N4010418
C D D R5 5 157, C9
1 1U N N 5kF 4 40 00 01 1 C Co on nn ne ec ct te ed d iin n S Se er riie es s t to o a an no ot th he er r 1 1N N4 40 00 01 1
R C C15
5
23, , C C9
9 O 1 1U U µPFF FTIONAL - Change to 1k for tons of gain, if you
R D1
43 d O 1NoP4Tth1IOi4s8N, aACls Loon-ncCehhcaatnengdgeeinct8oSte1orkie1fsµoFrtotoannsoothfegra1inN,4if1y4o8u
D5 d 1No4th0i0s1, aClsoonncehcatnegdeinc8Steorie1sµFto another 1N4001
ML Co
RO5d,
13Ce Cr
An9T d
IOisNtortion tone
C 1sUF
RL
O16CATION
1CO
dkoHPT
AI
thNO
isGN
, EA
al L
sT
oO-
c:Change to 1k for tons of gain, if you
R14
6
10 kk hange c8 to 1µF
C R140 .1000k1µF
C LO5 1 1,0 0CCA9TION
3.. C0 0.3 0 0k 1 1µ µF F
D C R4
156, C9 L
3 1E .k3Dk
D R414 L1E0kD
C10 .001µF
VL Cin
DO5ta,
44 C gCAe9T d
IOisN tortion tone
C 3s.3k
D LO5CATION L C LE EHD DANGE TO:
C D D5
53 . L L0E E3D D3µF
R C C13 36 1..0 0k3 33 3µ µF F
C R LO161CATION .
1 C0k1µF
C D511 . L0E1DµF
C3 .033µF
IR f y1o6u like the general so1uknd of the DS- 1 but are looking less highs and more of
aLCOt1oC1naAl TraIOngNe change C1C.01tµ o Fa capacitor with a larger value. Stock is .01µF for a
fC LreO1q0CueAnTcIyOrNoll-off of 7. 2.C k0H1z5.µF 48kHz
LC
es1
s0
s
hri
ll highs .02125µF 34.82kkHHzz
C10 .02722µF 233.622kHz
C LO10CATION . C0H3
23 7AµNFGE TO
2 F. R1 6EkQHz UENCY ROLLOFF
C C1100 ..00431735µµFF
124.851kkHHzz
C C1100 ..004272µµFF
13..52kkH Hzz
C10 .027µF 2.6kHz
C10 .033µF 2.1kHz
C10 .047µF 1.5kHz
All in all, the Boss DS- 1 Distortion is an inexpensive pedal that can rival many of
the best boutique pedals simply by changing the circuitry a little. While this may
seem difficult, technical and out of reach it really is very simple if you know what
to change and where to change it. I hope that I’ve given you the knowledge
and courage necessary to change your pedal from a mouse into a monster.
Happy soldering!
Brian Wampler
Brian Wampler is an author, effects designer/builder
and operates IndyGuitarist.com and Wamplerpedals.com.
His books include How to Build Effect Pedals, How
to Modify Effect Pedals, and Advanced DIY Effect Pedals
available at Guitar Tone.net.
