Electro-Harmonix Sovtek Deluxe Big Muff Pi sovtek-deluxe-big-muff-pi-manual

Sovtek Deluxe Big Muff Pi

Congratulations! You have just purchased the passionate lovechild of our revered Green Russian
Big Muff Pi reissue and the Big-Muff-on-steroids Deluxe Big Muff Pi: the Sovtek Deluxe Big Muff
Pi! We know what you’re thinking – “Oh, no, they didn’t!” Oh, yes, we did! It’s the beefy, woolly
tone you love from the Green Russian Big Muff with all the bells and whistles from the Deluxe Big
Muff. Check it out.

Features Include:

• Big Muff Knob Layout – familiar Sustain, Tone and Volume controls

• MIDS EQ – fully parametric MIDS EQ includes variable frequency sweep, boost or cut

level control and switchable Q or bandwidth amount

• Footswitch for MIDS EQ – turn on the MIDS EQ circuit with the stomp of your foot

• Gate – remove unwanted hiss and hum

• Blend – allows you to mix the dry signal with the distortion

• Wicker switch – opens up the high end for extra attack

• Expression Pedal Input – sweep the frequency of the MIDS EQ with your foot

• True Bypass

CONTROLS

VOLUME Knob – Works as a master volume control for the entire pedal

BLEND Knob – This mixes between the dry and distorted signals. Turn this knob fully

counterclockwise for 100% dry signal and fully clockwise for 100% wet signal. Setting the BLEND
knob to noon yields a 50/50 mix of dry/distorted signal.

TONE Knob – Provides a range of sounds from high treble to deep bass. As you turn the TONE
knob clockwise, treble increases and bass decreases.

SUSTAIN Knob – As in the original Big Muff Pi, adjusts the amount of sustain and distortion

Wicker Switch – This feature is the same as the switch found on the Big Muff Pi with Tone

Wicker. With the switch up, the wicker is engaged and high frequency bandwidth is opened up
for a bright and clear top end and more pronounced attack. With the switch down, the effect is
disengaged and the Big Muff circuit is back to stock.

GATE Knob – Turning GATE clockwise raises the Gate threshold requiring greater input amplitude
to open the noise gate, allowing your notes to be heard and your instrument to pass through.
Turn the GATE knob down all the way, to fully counter-clockwise, to disable the noise gate.

MIDS LEVEL Knob – When MIDS is engaged (LED near MIDS Footswitch is lit) the MIDS LEVEL
knob either boosts or cuts up to +/- 10dB, at the frequency set by the FREQ knob located below
it. Turn MIDS LEVEL clockwise from its center 12 o’clock position to boost the center frequency.
To cut, turn MIDS LEVEL counter-clockwise from the 12 o’clock position. This knob has a notch
near the 12 o’clock position to help identify the center of the knob’s travel. In the center position,
MIDS EQ is flat; it does not boost or cut. The MIDS LEVEL knob has no function when MIDS is
bypassed (LED near MIDS Footswitch is off).

MIDS FREQ Knob – Sets the center frequency of the MIDS EQ circuit ranging from 310Hz to

5.0kHz. To hear the range of the MIDS FREQ knob, turn the MIDS LEVEL knob up past 3 o’clock,
make sure MIDS is enabled (LED near MIDS Footswitch is lit), then play your instrument while
turning the MIDS FREQ knob. This knob has no function if either the MIDS section is bypassed
(LED near MIDS Footswitch is off) or the MIDS LEVEL knob is set to its center position.

The MIDS FREQ knob can be controlled by an external expression pedal or control voltage (CV).
Connect the external device to the EXP jack on the input side of the Sovtek Deluxe Big Muff. The
position of the MIDS FREQ knob sets the toe position of the expression pedal or maximum

frequency for CV. The heel position of the expression pedal equals the MIDS FREQ knob’s fully

counter-clockwise position. Please see EXP Input below for more on the expression pedal.

MIDS Q Switch (HIGH/LOW) – The Q switch sets the resonance or bandwidth of the MIDS
EQ. What this means is in LOW mode the EQ sounds broader or rounder and affects a larger
range of frequencies; in HIGH mode the EQ sounds sharper or peakier and affects a narrow range
of frequencies.

MIDS FOOTSWITCH / LED – Engages or bypasses the MIDS EQ section. When the white status
LED is lit, the MIDS EQ circuit is active and the MIDS LEVEL and FREQ knobs can be used to
produce a multitude of different tones.

BYPASS FOOTSWITCH / LED – Toggles between effect mode and true bypass. When the red
status LED is lit, the effect is active. When the LED is off, the Sovtek Deluxe Big Muff Pi is in True
Bypass mode.

I/O AND POWER CONNECTIONS

INPUT – Plug your instrument into here. The input impedance presented at this jack is

approximately 130k with the input buffer off. The input impedance is 1M with the input
buffer on.

OUTPUT – This is the output of the Sovtek Deluxe Big Muff Pi. Connect it to the input of your
amp or another effects pedal. The output impedance at the OUTPUT jack is 300 ohms.

EXP Input – Connect an expression pedal with a TRS plug to this jack to sweep the MIDS center
frequency with your foot or other extremity. Additionally, the EXP IN jack can be connected to a
Control Voltage (CV) source using a TS plug; the acceptable range for the control voltage is 0V to
5V. Some suggested Expression Pedals: EHX Expression Pedal, M-Audio® EX-P, Moog® EP-2,
Roland® EV-5 or Boss® FV-500L. The polarity of the expression pedal’s plug must connect the
Sleeve to the heel position, Ring connected to the toe position and the Tip connected to the wiper.
The nominal expression pedal impedance is 10k but it can accept impedances ranging from 6k to
100k. Please note: if the MIDS EQ section is bypassed, the expression pedal is disabled.

9V POWER – The Sovtek Deluxe Big Muff can run off of a 9V battery or you can use a 9VDC AC
Adapter capable of delivering at least 50mA. The optional 9V power supply from Electro-Harmonix
is the 9.6DC-200BI (same as used by Boss™ & Ibanez™) and delivers up to 200mA at 9.6 Volts
DC. The actual current draw of the Sovtek Deluxe Big Muff is 22mA at 9VDC. The AC Adapter
must have a barrel connector with center negative plug. The Sovtek Deluxe Big Muff accepts most
BOSS® style AC Adapters. Please do not exceed 12VDC at the power jack. The battery may be
left in or taken out when using an AC Adapter.

OPERATION AND WARNINGS

CHANGING THE BATTERY

To change the 9-Volt battery, you must remove the 4 screws on the bottom of the Sovtek Deluxe
Big Muff Pi. Once the screws are removed, you can take off the bottom plate and change the
battery. Please do not touch the circuit board while the bottom plate is off or you risk damaging
a component.

SHIELDING
To achieve its long sustain, the Sovtek Deluxe Big Muff Pi has a very high maximum gain. This
requires that pickups and cables be well shielded and properly grounded to avoid excessive hum
when high sustain knob settings are used.

INTERNAL INPUT BUFFER SWITCH & TRIM POTS
We have included an internal slide switch to engage a buffer on the input to the Big Muff circuit.
Engaging this buffer will increase the high end content of both the distorted and clean signal being

blended in. The slide switch is located near the input jack and is set to the “unbuffered” position

at the factory. Be careful not to touch any other components when adjusting this switch.

The Sovtek Deluxe Big Muff Pi’s MIDS EQ section has three trim pots for adjusting the following:

1) High Q bandwidth, 2) High Q Output Volume and 3) overall MIDS EQ Output Volume. We set
these trim pots at the factory so that 1) HIGH Q mode is very resonant but does not self-oscillate,

2) HIGH Q mode is just a bit louder than LOW Q mode and 3) when engaged, MIDS EQ creates
a slight volume boost over MIDS EQ bypassed for most settings of MIDS knobs.

We realize our settings may not be perfect for everyone. If you would like to make adjustments
to the trim pots, remove the 4 screws on the bottom of the unit and remove the bottom plate.
Place the pedal knob-side-down with the power jack facing away from you. In the upper left area
of the printed circuit board you will see three small trim pots.

Before you start: we recommend you photograph or sketch the position of each trim pot as it
came to you from the factory in case you want to go back to those settings. The factory trim pot
settings vary considerably from unit to unit.

When adjusting the trim pots use a small flat head or slotted screwdriver with a width of 2mm.
Please do not touch any other parts of the circuit board while the bottom plate is off or you risk
damaging a component.

The signal path through the trim pots goes in this order:

HI Q AMT (TRIM1) → HI Q VOL (TRIM2) → MID EQ OUT VOL (TRIM3)

Change HI Q’s bandwidth by adjusting HI Q AMT. The volume level of HI Q mode also changes:

increasing HI Q AMT increases HIGH Q’s volume; decreasing HI Q AMT decreases HIGH Q’s

volume. Therefore if you adjust HI Q AMT you may also need to adjust the HI Q VOL trim pot.

If you want to change the volume of LOW Q mode: 1) adjust the MID EQ OUT VOL trim

appropriately until you are happy with LOW Q’s volume, 2) compare HIGH Q’s volume to LOW Q’s

volume and adjust the HI Q VOL trim if necessary.

WARRANTY INFORMATION

Please register online at http://www.ehx.com/product-registration or complete and
return the enclosed warranty card within 10 days of purchase. Electro-Harmonix will
repair or replace, at its discretion, a product that fails to operate due to defects in
materials or workmanship for a period of one year from date of purchase. This
applies only to original purchasers who have bought their product from an authorized
Electro-Harmonix retailer. Repaired or replaced units will then be warranted for the
unexpired portion of the original warranty term.

If you should need to return your unit for service within the warranty period, please
contact the appropriate office listed below. Customers outside the regions listed
below, please contact EHX Customer Service for information on warranty repairs at
[e-mail] or [phone]. USA and Canadian customers: please obtain a
Return Authorization Number (RA#) from EHX Customer Service before returning
your product. Include  with your returned unit  a written description of the problem
as well as your name, address, telephone number, e-mail address, RA# and a copy of
your receipt clearly showing the purchase date.

United States & Canada Europe

EHX CUSTOMER SERVICE JOHN WILLIAMS
ELECTRO-HARMONIX ELECTRO-HARMONIX UK
c/o NEW SENSOR CORP. 13 CWMDONKIN TERRACE
47-50 33RD STREET SWANSEA SA2 0RQ
LONG ISLAND CITY, NY 11101 UNITED KINGDOM

Tel: [phone] Tel: [phone]
Email: [e-mail] Email: [e-mail]

The CE logo indicates that this product has been tested and shown to conform
with all applicable European Conformity directives.