Stereo Electric Mistress Instructions

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Plug your guitar into the INPUT jack and run a cable from the Main Output to your amplifier. If you want to produce lush Stereo flanges run a second cable from the Stereo Output to a second amplifier.  There are three basic controls on the STEREO ELECTRIC MISTRESS.

1.Rate Knob: This knob controls the speed or rate of the LFO signal that modulates the flanger. It also controls the rate of the Chorus effect. As you turn the Rate knob up the rate will increase. When the Rate knob is turned down between fully counter-clockwise and the 10 o’clock position, the Stereo Electric Mistress will enter Filter Matrix mode. In Filter Matrix mode the LFO signal is disconnected from the Flanger and Chorus so that you can manually modulate the Flanger/Chorus by turning the Rate knob. Keep the Rate knob below 10 o’clock to keep it in Filter Matrix mode.
1. Flanger Depth Knob: Controls the amount of Flange that is mixed with the direct signal. The more you turn the knob clockwise, the more pronounced the flanger effect.

2. Chorus Depth Knob: Controls the amount of the sweet chorus sound. The more you turn the knob clockwise, the more pronounced the chorus effect.

Hint: The Flanger and Chorus effect can be used together. While both produce rich sweeping textures on their own, together they can produce dramatically different and warm sonic textures that are not available when one effect is used alone.

STATUS LED - This LED indicates the current state of the unit.  When the LED is lit up, the box is in EFFECT mode. When the LED is off, the box is in BYPASS mode.  Pressing the Footswitch will toggle

INPUT Jack - This 1/4” jack is the audio input to the Stereo Electric Mistress. The input impedance presented at the Input Jack is 2 M(.

MAIN OUT Jack - This 1/4” jack is the main effect output jack. Use this jack when connected the Stereo Electric Mistress in mono. The output impedance at this jack is 820 (.

STEREO OUT Jack - This 1/4” jack is the stereo effect output jack. Connect this jack to your second amp or second mixer channel when connecting the Stereo Electric Mistress in stereo. The output impedance at this jack is 820 (.

9V Power Jack - Connect the output plug from the AC Adapter that was supplied with your Stereo Electric Mistress to this jack, located at the top of the unit. The Stereo Electric Mistress accepts Boss style AC Adapters.

The flanging effect can be thought of as a pitch slowly sweeping between high and low limits superimposed on the guitar signal.  The RATE control allows you to change the speed at which the sweep occurs.  With the RATE control fully counter-clockwise, you enter the Filter Matrix mode, which extends to the 10’o'clock position of the knob.  Turning the dial clockwise increases the rate to the point where the frequency of the input signal appears to be shifted in a vibrato-like fashion. The Chorus effect follows the same principal but produces a lush chorus where the rate control is applied to the Chorus and Flanger share identically.

The STEREO ELECTRIC MISTRESS has been set at the factory for maximum color capacity in the FLANGER mode.  One of the unique settings that was inherited from the legendary DELUXE ELECTRIC MISTRESS is the Filter Matrix mode. The harmonic makeup of the flange remains while no frequency modulation is applied. Different tonalities can be obtained when the RATE knob is set between a totally off position to around 10 o’clock position. 

Unplug after use.  Avoid operating near moisture. Rock-n-Roll!

WARNING: Use only the 9.6VDC/200mA AC adapter the Stereo Electric Mistress comes supplied with.  Do not use any other AC adapters. Using other AC adapters, even those made by Electro-Harmonix, could cause harm to the unit, the adapter or you. The Stereo Electric Mistress does not use batteries.


Please register online at 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 or +1-718-937-8300. 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, and RA#; and a copy of your receipt clearly showing the purchase date.

United States & Canada
55-01 2ND STREET
Tel: 718-937-8300

Tel: +44 179 247 3258

This warranty gives a purchaser specific legal rights.  A purchaser may have even greater rights depending upon the laws of the jurisdiction within which the product was purchased.

To hear demos on all EHX pedals visit us on the web at
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Note: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.

Modifications not expressly approved by the manufacturer could void the user’s authority to operate the equipment under FCC rules.

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Quick Specs
Truly independent stereo outputs
Individual flanger
Individual chorus
Chorus and flanger may be used together
Filter matrix mode available allowing you to manually sweep the flanger
Tough and compact die-cast chassis
96DC-200BI power supply included
Dimensions in inches: 4.0 (w) x 4.75 (l) x 2.25 (h)
Dimensions in mm: 102 (w) x 121 (l) x 89 (h)
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