Tech Talk; Electronic Crossover - Gallien-Krueger 2001RB Owner's Manual

Tech Talk

Characteristics of the 2001RB:
The 2001RB is a fl exible, state-of-the-art Bass Ampli-
fi er, designed to deliver maximum performance, and be
simple to operate. This is accomplished through a few,
.
very important features:
· Extremely high current power supply andpower
amp circuitry, gets the sound out of your head.
.
· Bi-Amp sound, two power amps, 540 Watts for
the woofer (1080W bridged), and 50 Watts for
the horn.
.
· Electronic crossover, seamless two-way
sound.
.
· Four, Bass specifi c bands of active
equalization for precise tone control.
.
· Three voicing fi lters for shaping and
customizing your sound.
.
· Balanced direct output with level control
eliminates need for a direct box.
. .
· Continuously variable fan cooling.
· Designed and Built in the U.S. for years of
reliability and quality service.
High Current Output & Bass Response:
When a power amplifi er is pushing several speaker cones,
and a high-power transient like a string slap comes along,
the amp has to tap into a large power reserve to maintain
cone control. It's kind of like grabbing a swing at the
bottom of it's travel and trying to push it the other way
- it could knock you over. If the amplifi er doesn't have
this ability, the sound is unresponsive and less out front.
The amp loses it's punch and feel at higher playing levels.
Instead of responding to your every command, the ampli-
fi er simply cuts those transients off, leaving you with the
feeling that something is missing in your sound.
Since most amplifi ers have limited output current capac-
ity, they need "current limiting circuits" to protect against
self-destruction. High-power transients trigger these
circuits, which rob the amplifi er of it's ability to control
speaker cones. This creates a mushy, unresponsive feel
to your sound. The 2001RB has extremely high current
capacity, so it doesn't need current limiting circuits for
over-load protection.
2001RB & 2001RBP
There is nothing in the 2001RB power amp to come be-
tween you and your sound except faithful, raw power.
Bi-Amp Sound:
Bass players have always liked the growl they get from
slight overdrive. In GK amps this comes partly from the
boost circuits and partly from the power amp. The prob-
lem is that growl, sounds great through woofers, and hor-
rible through horns. In the typical full range system with
a passive crossover, there is no way to get growl and keep
the defi nition that the horn provides. The horn always has
to be turned down. In a Bi-Amp system like the 2001RB,
the woofer and the horn, each have their own power amp,
allowing us to get growl in the woofer only, while keeping
the horn sound crystal clear. Now you can over-drive the
woofer as much as you want, and leave the horn all the
way up, keeping the defi nition it brings to your sound.
Running the 2001RB in Bi-Amp mode through a GK-RBH
cabinet, for the fi rst time allows full access to the benefi ts
of Bi-Amp sound. This is the reason the 2001RB is a Bi-
Amp, and it is the reason you will be able to explore an
entirely new territory of Bass sound.

Electronic Crossover:

Bi-Amp systems allow the crossover to be electronic and
therefore, have much higher quality than passive cross-
overs. A crossover separates the sound into two parts (high
and low frequency). The highs are sent to the horn or
high frequency cabinet and the lows are sent to the woofer.
In an ideal system, adding the highs and the lows back
together would recover the original signal. Most passive
Bass systems have very poor crossovers, resulting in severe
signal corruption. When these signals are added back
together (as in your ear), they have very little in common
with the original signal. The 2001RB uses a Constant
Voltage crossover which results in very little signal corrup-
tion. In fact, when the high and low signals are added
back together, the result is extremely close to the original.
This makes a two-way system sound more seamless, and
less artifi cial. We have also included a Tweeter Hi-Cut
switch in the crossover, which rolls the tweeter off above
10kHz giving it a less glassy, more cone like sound.
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