Manual

ManualsBrandsRane ManualsAudioAC 22B (1998 version)

Manual-1

AC 22B

ACTIVE CROSSOVER

OPERATORS MANUAL

AC 22B CONNECTION

In agreement with IEC and AES/ANSI standards, AC 22B

wiring convention is pin 2 Positive, pin 3 Negative (return),

pin 1 Signal ground (for unbalanced use), with the connector

case or shell tied to chassis ground.

BALANCED OPERATION

Use only when driving from a true balanced source and

driving to a true balanced destination—either transformer

coupled or active drive. Connect the input to pins 2 and 3

with pin 2 positive. Do not connect pin 1. Terminate the

shield to the case or shell. Connect the output to pins 2 and 3

with pin 2 positive. Do not connect pin 1. Connect the shield

to the case or shell.

UNBALANCED OPERATION

Connect the input between pins 2 and 1 with pin 2 positive

and pin 1 Signal ground. Short pin 3 to pin 1. Terminate the

shield to the case or shell. Connect the output between pins 2

and 1 with pin 2 Positive. Leave pin 3 open—do not short it

to pin 1. Connect the shield to the case or shell.

COMBINATION OPERATION

For combined balanced and unbalanced operation, use

whichever half of the above instructions apply for each end.

See the “Sound System Interconnection” RaneNote

included with this manual for more information on cabling

and grounding requirements.

QUICK START

The AC 22B can be either a Stereo 2-Way or Mono 3-Way crossover. Labels above the controls refer to the unit being

operated in the 2-Way Stereo mode. Labels below the controls refer to the unit being operated in the 3-Way Mono mode.

The AC 22B is a fully balanced output version of the popular AC 22 and is equipped with XLR conectors instead of

the standard ¼" TRS jacks. All other features, specifications and operation are identical with the standard model with an

added switch. Where the AC 22 is configured somewhat automatically by using switching jacks, the AC 22B is config-

ured by a SYSTEM MODE switch added to the back of the unit.

To operate the AC 22B in Stereo 2-Way mode, be sure that the Mode switch is set for STEREO 2-WAY. Follow the

labels above the controls and jacks.

When operated in the Mono 3-Way mode, the switch should be set in the MONO 3-WAY position. Follow the labels

below the controls and jacks. In Mono 3-Way mode the Channel 1 High Output is unusable. This output is the high-pass-

only portion of the midrange filter. The Channel 1 High Level and the Channel 2 Master Level are also defeated on the

front panel.

NEVER CONNECT ANYTHING EXCEPT AN RS 1 OR OTHER APPROVED RANE AC POWER SUPPLY

TO THE THING THAT LOOKS LIKE A TELEPHONE JACK ON THE REAR. This is an AC supply and requires

some special attention if you do not have an operational power supply EXACTLY like the one that was originally

packed with your unit.

WEAR PARTS: This product contains no wear parts.

Summary of content (13 pages)

PAGE 1
OPERATORS MANUAL AC 22B ACTIVE CROSSOVER QUICK START The AC 22B can be either a Stereo 2-Way or Mono 3-Way crossover. Labels above the controls refer to the unit being operated in the 2-Way Stereo mode. Labels below the controls refer to the unit being operated in the 3-Way Mono mode. The AC 22B is a fully balanced output version of the popular AC 22 and is equipped with XLR conectors instead of the standard ¼" TRS jacks.
PAGE 2
FRONT PANEL: STEREO 2-WAY CONFIGURATION Observe the labels screened above the controls for stereo operation. POWER switch: Self-evident. POWER indicator: When this yellow LED is lit the unit is ready to operate. CHANNEL 1 MASTER LEVEL controls the overall Level of Channel 1 without altering the relative settings of the HIGH and LOW Outputs. Unity gain for all LEVEL controls is at “7”. LOW LEVEL controls the Level of signal going to the LOW Output in this Channel.
PAGE 3
REAR PANEL: STEREO 2-WAY CONFIGURATION Observe the labels screened above the Inputs and Outputs for stereo operation. CHANNEL 1 INPUT connects to the left channel output of the mixer, equalizer or other source. CHANNEL 2 INPUT connects to the right channel output of the mixer, equalizer or other source. HIGH FREQUENCY OUTPUTS: Connect Channel 1 HF OUT to the left channel input of the high frequency amp, and the Channel 2 HF OUT to the right channel input of the high frequency amp.
PAGE 4
FRONT PANEL: MONO 3-WAY CONFIGURATION Observe the labels below the controls for Mono operation. POWER switch: Self-evident. POWER indicator: When this yellow LED is lit, the unit is ready to operate. CHANNEL 1 MASTER LEVEL controls the overall Level without altering the relative settings of the HIGH, MID and LOW Outputs. Unity gain for all Level controls is at “7”. LOW LEVEL controls the Level of signal going to the LOW Output.
PAGE 5
REAR PANEL: MONO 3-WAY CONFIGURATION Observe the labels below the Inputs and Outputs for Mono operation. MONO (CHANNEL 1) INPUT: Plug the output of the mixer, equalizer or other signal source to this Input for mono operation. Do not use the Channel 2 INPUT for MONO 3-WAY operation. HIGH FREQUENCY OUTPUT: Connect this Output to the input of the high frequency amp. MID FREQUENCY OUTPUT: Connect this Output to the input of the mid frequency amp.
PAGE 6
OPERATING INSTRUCTIONS Selecting Crossover Frequencies Most speaker manufacturers supply low and/or high frequency cut-off points for each driver, especially if these are supplied in a system. These cut-off frequencies are based on each driver’s performance at and beyond this point, with a certain safety margin to accommodate more gentle filter roll-offs and resultant higher output beyond the recommended performance range.
PAGE 7
Fine. So we put up with it. But to make matters worse, when the two drivers are horizontally displaced – that is, one is in the front of or behind the other, this “lobe” or dispersion pattern gets tilted (usually upward) toward the driver that is further behind (see Figure 1). This gets hard to put up with, because the end result is that your speaker system will have two, three, four or more tilted radiation patterns and only two or three people in the house will have decent seats.
PAGE 8
green or in yellow on Rane analyzers), slowing turn up the MID DELAY control on the crossover until the display shows +3 dB (Red LED just on with Rane analyzers). Now the drivers are electronically phase aligned and the MID DELAY control should be left in this position at all times unless the speaker system is physically altered. iii.
PAGE 9
emitted from both the high and mid drivers. Check the reading on the SPL meter: i. If the meter reads +3 dB, then the drivers are properly phase aligned and no Delay is necessary; leave the MID DELAY control at full minimum. ii. If the meter reads less than +3 dB, slowly turn up the MID DELAY control until the meter just reads +3 dB. Now the drivers are electronically phase aligned and the DELAY control should be left in this position at all times, unless the speaker system is physically altered. iii.
PAGE 10
Delay vs. Frequency Table If you do not have the equipment necessary to electronically align the system as described in the previous sections, you may use the table below to obtain a rough and approximate phase alignment of your drivers. Measure the horizontal displacement between the voice coils of the two adjacent drivers sharing the same crossover point, then find the column in the table nearest your actual displacement.
PAGE 11
Time Delay Transplant Modification We have added modification jumpers to the AC 22B. These jumpers permit the transplanting of the Delay circuits from one Output to another. As the units are shipped, the Delay circuit is not installed on the High Frequency Outputs. When the AC 22 was first designed, long throw horns were more common than constant directivity horns (CD horns). The long throw horn's diaphragm was the farthest sound emitter from the front of the speaker enclosure, (see Fig.
PAGE 12
Setting the Output Level Controls Choosing the crossover frequencies was the easy part. Now it gets real fun. The idea is to set the output LEVEL controls on the crossover so that the entire speaker system has a uniform, flat response. Unfortunately, the room in which the speakers are placed has a habit of always getting into the act, so things get messy. As a result there seems to be two schools of thought regarding the use of active crossovers. The Set-lt-Once-And-Glue-lt School.
PAGE 13
of a pink noise source. If so, be sure to look at several different tones within each crossover section to get a good average of driver response. 1. Run pink noise into the crossover Inputs (through the mixer or directly, as is convenient). 2. Make sure all crossover LEVEL(s) are turned all the way down and all amplifier level controls are at least half way up to start with. 3. Turn the crossover MASTER LEVEL(s) half way up. Place the SPL meter at least 15 feet from the speaker stack and about chest high.