Rane AC 22 User manual

AC 22 & AC 22B
ACTIVE CROSSOVERS
Data Sheet-1
Features
• Stereo 2-Way or Mono 3-Way
• Linkwitz-Riley Alignment with 24 dB per Octave Slopes
• Adjustable Delays
• Mono Subwoofer Switch and Output
• Infrasonic, Ultrasonic, and RFI Filters
• Low Output Muting (2-Way)
• Input & Output Level Controls
• UL/CSA/CE and 100/120/230 VAC Remote Power Supplies
drivers designed to produce a specific range of frequencies,
and no more, will not be driven past their limits, thereby
minimizing distortion and driver fatigue.
To further guarantee the transparent operation of the
AC 22 and AC 22B, adjustable Delay circuits appear on the
Low (& Mid when used in 3-Way mode) Outputs of each
Channel to compensate for any physical misalignment of the
drivers. Time correction ensures the mechanical phase
alignment of adjacent drivers will be acoustically correct, thus
maintaining the integrity of the electrical phase alignment of
the crossover’s filters. The Low Delay circuit may be inter-
nally transplanted to the High Output when neccessary. CD
horn equalization is also possible with an internal modifica-
tion.
See RaneNote 107 for more information regarding
Linkwitz-Riley designs.
General Description
The Rane AC 22 and AC 22B Active Crossovers are
Stereo 2-Way with mono subwoofer option, or can be used as
a Mono 3-Way. They employ state-variable 4th-order
Linkwitz-Riley filter alignments to minimize phase
difficulties in the critical crossover region. The model AC 22
utilizes ¼" TRS connectors with balanced/unbalanced inputs
and unbalanced outputs. The new AC 22B uses XLR
connectors with active balanced inputs and outputs.
Simply put, a Linkwitz-Riley alignment is two cascaded
2nd-order Butterworth filters exhibiting identical phase
characteristics on their Low pass and High pass Outputs. This
characteristic guarantees in-phase outputs at all frequencies.
In-phase outputs are mandatory for proper acoustic summing
of common signals from adjacent drivers in the crossover
region. An added benefit of this topology is steep 24 dB per
octave rolloff slopes. A slope of this magnitude guarantees
AC 22 Features
• ¼" TRS Inputs & ¼" TS Outputs
• Active Balanced/Unbalanced Inputs & Unbalanced Outputs
AC 22B Features
• XLR Inputs & Outputs
• Fully Active Balanced Inputs & Outputs
DATA SHEET

AC 22 & AC 22B
ACTIVE CROSSOVERS
Data Sheet-2
Parameter Specification Limit Units Conditions/Comments
Crossover: Alignment Linkwitz-Riley Proprietary 4th-order state-variable
..........Slopes 24 dB/octave
..........Range 70-3.6 kHz Low to High 41-detent continuously variable pot
Time Delay Adjust Range Off to +2 5% ms Low & Mid Outputs
AC 22 Inputs: Type Active Balanced/Unbalanced
..........Connectors ¼" TRS
..........Impedance 20k 1% ohms
..........Maximum Level +21 1 dBu
..........Gain Range Off to +6 -0/+4 dB
AC 22 Outputs: Type Active Unbalanced
..........Connectors ¼" TS
..........Impedance 100 1% ohms
..........Maximum Level +20 1 dBu 600 ohms or greater
..........Gain Range Off to +6 -0/+4 dB
AC 22B Inputs: Type Active Balanced
..........Connectors XLR pin 2 hot per AES standards
..........Impedance 20k 1% ohms
..........Maximum Level 21 1 dBu
..........Gain Range Off to +6 -0/+4 dB
AC 22B Outputs: Type Active Balanced
..........Connectors XLR pin 2 hot per AES standards
..........Impedance 200 1% ohms
..........Maximum Level +20 1 dBu 600 ohms or greater
..........Gain Range Off to +12 -0/+4 dB
Band Muting Switches Yes Low & Mid Outputs
RFI Filters Yes
Infrasonic Filter 20 Hz, 18 dB/oct., Butterworth 3% Hz
Ultrasonic Filter (AC 22) 40 kHz, 6 dB/oct., Bessel 3% Hz Linear phase
Frequency Response 20-40 kHz +0/-3 dB
THD+Noise 0.02 .01 % +4 dBu, 20-20 kHz
IM Distortion (SMPTE) 0.02 .01 % 60 Hz/7 kHz, 4:1, +4 dBu
Signal-to-Noise Ratio 92 2 dB re +4 dBu, 20 kHz noise bandwidth
Unit: Agency Listing
..........120 VAC model Class 2 Equipment National Electrical Code
UL & CSA Exempt Class 2 equipment
..........230 VAC model CE-EMC EMC directive 89/336/EEC
CE-Safety Exempt per Art. 1, LVD 73/23/EEC
Power Supply: Agency Listing Class 2 Equipment
..........120 VAC model UL File no. E88261
CSA File no. LR58948
..........230 VAC model CE-EMC EMC directive 89/336/EEC
CE-Safety LV directive 73/23/EEC
..........100 VAC model Built to JIS Japan only
Power Supply Requirement 18 VAC w/center tap 0.1 Vrms RS 1 (see data sheet)
..........Maximum Current 160 mA RMS Current from Remote Supply
Unit: Construction All Steel
..........Size 1.75"H x 19"W x 5.3"D (1U) (4.4 cm x 48.3 cm x 13.3 cm)
..........Weight 4 lb (3 kg)
Shipping: Size 4.25" x 20.3" x 13.75" (11 cm x 52 cm x 35 cm)
..........Weight 8 lb (5 kg)
Note: 0 dBu=0.775 Vrms

AC 22 & AC 22B
ACTIVE CROSSOVERS
Data Sheet-3
AC 22B Block Diagram
AC 22 Block Diagram

AC 22 & AC 22B
ACTIVE CROSSOVERS
Data Sheet-4 All features & specifications subject to change without notice. DOC 103033 PN 07 31 9-98
Rear Panels
©Rane Corporation 10802 47th Ave. W., Mukilteo WA 98275-5098 TEL [phone] FAX [phone] WEB http://www.rane.com
References
1. S.H. Linkwitz, “Active Crossover Networks for Noncoincident Drivers,”J. Audio Eng. Soc., vol. 24, pp. 2-8 (Jan/Feb 1976).
2. D. Bohn, “A Fourth-Order State-Variable Filter for Linkwitz-Riley Active Crossover Designs,”presented at the 74th
Convention of the Audio Engineering Society, New York, Oct. 9-12, 1983, preprint no. 2011.
3. D. Bohn, “Linkwitz-Riley Crossovers,”Rane Note 107, (1983).
4. D. Bohn, “Why Not Wye?”Rane Note 109, (1984).
5. D. Bohn, “Overload Characteristics of State-Variable Crossovers,”Rane Note 112, (1985).
6. D. Bohn, “Linkwitz-Riley Active Crossovers Up To 8th-Order: An Overview,”Rane Note 119, (1989).
Available Accessories
• SC 1.7 Security Cover
Architectural Specifications
The active crossover shall contain 4th-order Linkwitz-
Riley filters. Provisions shall exist to correct for driver
misalignment by means of adding time delay to the low
frequency outputs.
The crossover frequency shall be controlled by a continu-
ously variable control with 41 detents to allow mechanical
reference of crossover setting.
Signal inputs shall be active balanced/unbalanced designs
terminated with ¼" TRS (tip-ring-sleeve) connectors for the
AC 22, and active balanced terminated with XLR connectors
for the AC 22B. Signal outputs shall be unbalanced type
terminated in ¼" TS connectors for the AC 22, and active
balanced design terminated with XLR connectors for the AC
22B. RFI filters shall be provided. Infrasonic and ultrasonic
filters shall be built-in.
The active crossover shall afford an input level range of
off to +6 dB. The output level controls shall afford a level
range of from off to +6 dB (+12 dB for the AC 22B) with
muting capability on the low frequency outputs. The cross-
over shall supply two independent channels.
The unit shall be exempt from agency safety requirements
and powered from a UL listed, CSA certified remote power
supply (120 VAC) or CE approved (230 VAC) via a rear
panel input modular plug. The unit shall be constructed
entirely from cold-rolled steel, and mount into a standard 1U
EIA rack.
The unit shall be a Rane Corporation AC 22 or AC 22B
Active Crossover.
Choosing the Right
Configuration: Mono, Two-
Channel Mono or Stereo?
Very few systems indeed will utilize a two channel
crossover for the purpose of true stereo imaging. Discrete
stereo channels which are run from the mixing board are
usually used for panning effects and/or for separate equaliza-
tion of left and right speaker stacks. Different sides of the
room often require significantly different equalization due to
varying room acoustics, dimensions, positioning of speaker
stacks near walls, curtains and the like.
Even though you may not plan to use stereo equalization
or panning effects, it is recommended that your system utilize
discrete crossover channels for each stack of speakers to
ensure flexibility and control for consistent, optimum sound
quality. For example, if you plan to run a multi-stack system
mono three-way, use the AC 23 rather than the AC 22 for
separate control over each set of speakers—especially since
phase alignment may differ with each stack requiring separate
time delay adjustments. Even with only a single system
equalizer, the AC 23 can deliver the extra independent control
which can make a difference in sound throughout the listen-
ing area. If all drivers are built into a single cabinet, or you
are running bi-amped monitors, then the AC 22 is the one for
you.