
WARNING: Your Holy Grail Max comes equipped with an Electro-Harmonix 9.6DC-200BI
power supply (same as used by Boss® & Ibanez®: 9.6 Volts DC 200mA). The Holy Grail
Max requires 80mA at 9VDC with a center negative plug. Using the wrong adapter or a
plug with the wrong polarity may damage your Holy Grail Max and void the warranty.
HOLY GRAIL MAX
Reverb Pedal
Congratulations on your purchase of the Holy Grail Max, an easy to use, stellar
sounding reverb pedal from Electro-Harmonix. The HG Max delivers four types of
studio quality reverb: SPRING, HALL, PLATE and REVERSE all designed for the
discerning guitarist but also great with other instruments on stage or in the
studio. Included is a newly designed analog wet/dry control which provides a
constant volume curve as you turn the BLEND knob from fully dry to fully wet
while also keeping your dry signal analog through the pedal.
- REVERB DESCRIPTIONS -
SPRING – Spring Reverb is a simulation of the spring reverb found in many
classic guitar amps. In SPRING mode, the TIME knob controls both the size of
the springs and the overall decay time. As you turn the TIME knob clockwise, the
spring reverb gets bigger and longer.
HALL – is a simulation of the reverberations heard in large spaces such as a
concert hall or cathedral. In HALL mode, the TIME knob controls the decay time
of the reverb. As you turn TIME clockwise, the reverb time increases creating a
larger reverberant space. Using the TIME control you can obtain reverb spaces
ranging from a room to a large hall.
PLATE – is an emulation of a metal plate reverb commonly found in high end
recording studios during the 1960’s and 70’s. The Plate reverb is a very smooth,
tonally balanced sounding reverb that sounds great on many different
instruments, especially vocals. Turn the TIME knob clockwise to increase the
decay time of the PLATE reverb. When TIME is maxed, the PLATE reverb creates
a very long reverb decay; holding each note for over 30 seconds.
REVERSE – Reverse Reverb is an emulation of the reverse reverb trick
commonly performed in studios, where a note’s reverb fades-in, in reverse of
course, before the note is actually struck. The HG Max works in real time and

cannot create backwards reverb for a note before it is actually played so the
REVERSE reverb in the HG Max will create reverse reverb after the note is
sounded. The length of time between playing a note and hearing the reverse
reverb completely fade-in is set by the TIME knob. The further you turn TIME
clockwise, the longer the note will take to fade-in. For short TIME settings, the
REVERSE mode can sound like a slap-back echo.
- CONTROLS -
REVERB Switch Knob – Chooses the reverb mode. From left to right, the
modes are SPRING, HALL, PLATE and REVERSE.
TIME Knob – Adjusts the decay time, or reverb length/size, for the SPRING,
HALL and PLATE reverbs. In REVERSE mode, the TIME knob sets the length of
time between striking a note and the reverb fade-in. While in PLATE mode, when
TIME is set to its maximum position, the reverb decay is over 30 seconds
creating a lush reverb wash with each new note.
BLEND Knob – Controls the wet/dry mix from 100% Dry (counter-clockwise
position) to 100% Wet (clockwise position). As the BLEND knob is turned, the
overall output volume remains nearly constant. Your Dry signal remains analog
from input to output through the HG Max.
FOOTSWITCH and LED – The Footswitch selects whether the HG Max is
engaged or in True Bypass mode. When the effect is engaged, the LED is lit.
INPUT Jack – This ¼” jack is the audio input for the HG Max. The input
impedance is 1M.
AMP Jack – This ¼” jack is the audio output from the HG Max. The output
impedance is 550.
9V Power Jack – Plug the output of the AC Adapter supplied with the Holy Grail
Max into this jack located at the top of the enclosure. The HG Max draws 80mA
at 9VDC with a center negative plug and accepts Boss® and Ibanez® style AC
Adapters. Please do not allow the power supply voltage to exceed 10VDC. The
Holy Grail Max does not take batteries.

- 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 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 Ship to:
Canada - $15 Electro-Harmonix
Europe and outside countries - $25 C/O New Sensor Corporation
55-01 2nd Street
Long Island City, NY, 11101
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 info@ehx.com
Attn: Service Department
- FCC COMPLIANCE -
This device complies with part 15 of the FCC Rules. Operation is subject to the following
two conditions: (1) This device may not cause harmful interference, and (2) this device
must accept any interference received, including interference that may cause undesired
operation. If the device is not installed and used in accordance with the instructions, it
may cause harmful interference to radio communications and void the user's authority to
guarantee the equipment.
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.
Modifications not expressly approved by the manufacturer could void the user's authority to
operate the equipment under FCC rules.
Consult the dealer or an experienced radio/TV technician for help.