Electro-Harmonix Hot Tubes Instruction Manual

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HOT TUBES

Congratulations on your purchase of the Hot Tubes overdrive, a faithful reissue
of the original 1970s Electro-Harmonix classic, now in a compact pedalboard­friendly enclosure. Since its initial release in 1978, countless musicians have
prized the scorching tube amp simulation the Hot Tubes delivers. They consider
the original Hot Tubes to be indispensable, so it is rarely available on the vintage
market. Now there is no need to search. The Hot Tubes reissue gives you the
exact same tone and drive as the original.

- CONTROLS -

OVERDRIVE Knob – Controls the amount of input gain and distortion delivered

by the Hot Tubes. As you turn OVERDRIVE clockwise, the distortion ranges from
mild tube-like breakup to saturated distortion.

TONE Knob – Creates a range of tones from warm bass to bright treble as the
knob is turned clockwise.

VOL Knob – Sets the output volume of the HOT TUBES.

TONE Switch – When this switch is set to OFF, the HOT TUBES Tone knob is

disabled, resulting in a more powerful, direct tone. When the TONE SWITCH is
set to ON, the TONE KNOB behaves normally.

FOOTSWITCH and LED – The footswitch selects whether the HOT TUBES is
engaged or in true bypass mode. When the effect is engaged, the LED will be lit.

INPUT Jack – This ¼” jack is the audio input for the HOT TUBES. The input
impedance is 100k.

AMP Jack – This ¼” jack is the audio output from the HOT TUBES. The output
impedance depends on the VOLUME setting, ranging from 350 to 3k.

9V Power Jack – The HOT TUBES can run off of a 9V battery or you can use an
optional 9VDC AC Adapter capable of delivering at least 50mA to the 9V power
jack. The AC Adapter must have a center negative plug. The battery may be left
in or taken out when using an AC Adapter. The Hot Tubes draws 18mA at 9VDC.

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- CHANGING THE BATTERY -

To change the 9-volt battery, you must remove the 4 screws on the bottom of
the HOT TUBES. 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.

- 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. Electro­Harmonix 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
include a brief description of the problem as well as your name, address,
telephone number, copy of your receipt, and a check or money order.

United States - $12
Canada - $15
Europe and outside countries - $25

Ship to:

Electro-Harmonix
C/O New Sensor Corporation

55-01 2nd Street
Long Island City, NY, 11101

Attn: Service Department

Please make checks/money orders payable to New Sensor Corporation.
To hear demos on all EHX pedals visit us on the web at www.ehx.com

Email us at [e-mail]