Deer Creek Audio EQ901 B Series User manual

EQ901 B Series User Guide
Introduction 1
1. Features 2
2. What’s Included 2
3. Typical Installation Examples 2
3.1 Tape Monitor Loop Setup 3
3.2 Preamp / Power Amplifier Setup 3
3.3 Connecting a Power Subwoofer 4
3.4 Typical Setup I/O 5
3.5 AC Power Connection 5
4. Setting Input Levels 5
5. Accessing the Input Level Switches 6
6. Using the Dual Equalization Curves - Tone Modes 6
7. Specifications 7
8. Warranty Terms 8
Contact Deer Creek Audio 8
Introduction
The Deer Creek Audio EQ901 B Series is a direct replacement for existing BOSE 901
equalizers. The EQ901 B features dual output equalization (EQ) curves, Normal and
Enhanced, either of which will accommodate your 901 Series and can be selected based on
personal preference. See below for instructions on using this feature.
The EQ901 B installs in your tape monitor loop, pre-out/pre-in loop or between your preamp
and power amp. Switchable input levels between 0.9 Vrms and 2.0 Vrms accommodate use
with most preamplifiers, amplifiers or receivers. The EQ901 B series is based on the miniDSP
2x4 digital signal processor.
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1. Features
● Precision engineered BOSE 901 Series equalization
● Dual equalization curves - tone modes
○ Standard - enhanced bass depth and treble range
○ Small room - slightly reduced bass and enhanced mid-range
● Ultra low noise and proven reliability
● Based on the miniDSP 2x4 digital signal processor
2. What’s Included
● EQ901 B Equalizer
● Frequency equalization curves for your 901 Series
● Regulated power supply
3. Typical Installation Examples
Analog audio input and output connections are made directly to the RCA input and output
jacks. For RCA connections, #1 is Left (L) and #2 is Right (R). When making these
connections, make sure to power off the equipment being connected.
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3.1 Tape Monitor Loop Setup
3.2 Preamp / Power Amplifier Setup
This example shows a typical connection between a preamp and power amp.
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If you have a receiver or integrated amplifier with a pre-out / main in loop, you can insert the
EQ901 B as shown below.
3.3 Connecting a Power Subwoofer
The two unused outputs connect to your subwoofer L and R line inputs. The subwoofer
controls can then be adjusted to your preference.
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3.4 Typical Setup I/O
3.5 AC Power Connection
The EQ901 B does not have a power switch and can be left powered on, as power
consumption is very low. You also may power your EQ901 B from a switched outlet on your
receiver.
4. Setting Input Levels
The analog audio input levels are switchable between 0.9 Vrms and 2.0 Vrms to accommodate
use with most preamplifiers, amplifiers or receivers. If you are experiencing excessive signal
level or distortion, you may need to switch the unit to the 2.0 Vrms setting.
The EQ901 B model is shipped with the input levels preset to 0.9 Vrms.
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0.9 Vrms position. With this setting, the maximum input signal voltage allowed before clipping
the A/D convertor is 0.9 Vrms. This position is typically used when the EQ901 B is connected
between a preamp and a power amplifier.
2.0 Vrms position. With this setting, the maximum input signal voltage allowed before clipping
the A/D convertor is 2.0 Vrms. This position is typically used when the EQ901 B is connected
in a tape recording loop (REC/in to PB/out).
5. Accessing the Input Level Switches
6. Using the Dual Equalization Curves - Tone Modes
The EQ901 B is equipped with two equalization (EQ) curves - tone modes. The Standard EQ
curve - tone mode is available on outputs 1 and 2, and the Small Room EQ curve - tone mode
is on outputs 3 and 4.
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If you're using an amplifier or receiver with two tape monitor loops, you can connect the EQ901
B outputs 1 and 2 to tape playback inputs 1, and outputs 3 and 4 to tape playback inputs 2.
Then you will be able to switch easily between the two equalizer curves. If your configuration is
a pre-amplifier out / main amplifier in setup, you'll need to manually move the cables from
outputs 1 and 2 to outputs 3 and 4. Be sure to power off all equipment before making
these adjustments.
7. Specifications
● Distortion < 0.01% THD
● Maximum input voltage: 2.0 Vrms or 0.9 Vrms - jumper settable
● Dynamic range > 98dB
● Analog Devices: ADAU1701 Digital Signal Processor Engine
● Dimensions: 26 h x 107 w x 94 d mm
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8. Warranty Terms
This product is warranted to be free from defects in materials and workmanship for a period of
one year from the invoice date. Warranty does not cover failure of the product due to incorrect
connection or installation, improper or undocumented use, unauthorized servicing, modification
or alteration of the unit in any way, or any usage outside of that recommended in this manual.
Return shipping is the responsibility of the customer.
Contact Deer Creek Audio
Please contact us with any questions or comments:
[email protected]
720.726.9272
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