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Introduction
Congratulations, you just purchased a completely new concept in acoustic instrument amplifica-
tion, The Hartke Acoustic Ribbon Series. The Hartke Acoustic Ribbon series faithfully reproduces
the sound of the any acoustic instrument thanks to their reference grade power amplifier sec-
tion and unique speaker system featuring 5-inch, full range drivers and a 2 x 4 inch, planar rib-
bon transducer. The amplifiers are available in two versions, the AC75 with dual 5-inch drivers
and 75 watts of power, and the AC150 with four 5-inch drivers and 150 watts of power. Both
amplifiers feature two input channels with Channel 1 providing inputs for passive or active
acoustic guitar pick-ups, and Channel 2 providing XLR mic and dual RCA line inputs. A vari-
able Notch Filter and Phase switch are also included to help reduce feedback. The AC75 and
AC150 also feature a 5-band graphic equalizer to shape the overall tonal response. Dazzling
multi effects like delay, reverb and chorus are available from the built-in, 100 preset, 24-bit
digital effect processor. In addition, the AC150’s full-range speakers are arranged in stereo
so that reverbs and chorus effects pan left and right. The rich brown enclosures have been
beautifully appointed with gold hardware and feature Hartke’s trademarked Kickback™ design
and time-tested rugged construction. While the Acoustic Ribbon Series are packed with all the
features demanded by the most discerning acoustic artists, what makes the amplifier special is
the unmatched sonic performance. The Acoustic Ribbon amplifiers are the perfect solution for
electric acoustic guitars, and also, for multi instrumentalists who play electric violin, mandolin,
Dobro and other acoustic electric instruments too. To build a fine acoustic instrument, a luthier
must pay special attention in the selection of the various components like the wood for the
top, sides and neck, as well as, the construction of the internal bracing. Hartke engineers have
applied the same careful approach in the selection of the critical components and with the
internal construction to produce a sound that is truly unique to the Acoustic Ribbon amplifiers.
The full range 5-inch drivers, provide a smooth and even frequency response without the low
frequency resonance associated with larger drivers. The ribbon transducer provides sweet high
frequency response without the resonance and distortion that comes with standard tweeters.
The result is sound reproduction that is totally true to the sound of the instrument it is amplify-
ing. Simply put, the amps sound like your instrument, only louder.
Although these units are designed for easy operation, we suggest you first take some time to go
through these pages so you can fully understand how we’ve implemented a number of unique
features. In these pages, you’ll find a detailed description of the many features of the AC75 and
AC150 acoustic amplifiers, as well as a guided tour through it's front and rear panels, step-by-
step instructions for setting up and using the product, detailed discussions about equalization
and compression, and full specifications. You’ll also find a warranty card enclosed—please
don’t forget to fill it out and mail it so that you can receive online technical support and so we
can send you updated information about these and other Hartke and Samson products in the
future.
With proper care and adequate air circulation, your AC75 or AC150 will operate trouble free for
many years. We recommend you record your serial number in the space provided below for
future reference.
Serial number: __________________________________
Date of purchase: ________________________________
Should your unit ever require servicing, a Return Authorization number (RA) must be obtained
before shipping your unit to Samson. Without this number, the unit will not be accepted. Please
call Hartke at 1-800-3SAMSON (1-800-372-6766) for a Return Authorization number prior to ship-
ping your unit. Please retain the original packing materials and if possible, return the unit in the
original carton and packing materials.