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Knowledge Base > Discontinued Products > 610 Broadcast Audio Delay

Where can I find a Flow Chart for the 610 Broadcast Audio Delay?

How do I exit delay for traffic reports and remotes on the 610?

Live traffic reports and commercial remotes require off-air monitoring and cueing. If the station broadcasts in delay, the reporter will hear his cue 7.5 seconds late which will result in 7.5 seconds of dead-air. In radio, 7.5 seconds of dead-air is a capital offense. There are operational procedures which will prevent the problem.

When using the full-dump mode: During delayed programs which include live traffic reports or news reports, the on-air talent must instantly return to real time for the live remote. This requires that the 610 be operated in the full-dump mode; all 7.5 seconds of delay must dump when the DUMP button is pushed. This procedure will not work properly when the 610 is in the two-stage dump mode.

Shortly before the live report the board operator must put the Symetrix 610 in the EXIT mode. The 610 begins backing down to real time. Next, the air talent gives the traffic reporter his standard verbal cue and stops talking. Immediately switch the studio monitors to off-air monitoring. When the verbal cue for the traffic reporter is heard, the board operator pushes the DUMP button on the 610. The station is now on-air at real time for the traffic report. At the end of the report the board operator should push the START button and the 610 will begin building back the 7.5 second delay.

1. Before the live report, put the 610 in the EXIT mode.
2. Give the remote talent their normal verbal cue.
3. Switch the studio to off-air monitoring.
4. When the verbal cue is heard on the air, push the DUMP button. (This puts the station on-air in real time.)
5. At the end of the live report, push the START button.
6. Switch the studio monitors back to “board output.”

When using the half-dump mode: During delayed programs which include live traffic reports or news reports, the on-air talent must instantly return to real time for the live remote. This method operates in either the full-dump or half-dump mode. You must provide the operator with the remote BYPASS function in the form of a SPST switch wired between pins 13 and 14 of the remote connector J8. (See your 610 User’s Manual.)

Shortly before the live report the air talent gives the traffic reporter his standard verbal cue and stops talking. Immediately switch the studio monitors to off-air monitoring. When the verbal cue for the traffic reporter is heard, the board operator pushes the remote BYPASS/OPERATE button. This forces the 610 into the BYPASS mode and the station is on-air in real time for the traffic report.

At the end of the report the board operator should push the remote BYPASS/OPERATE button and then the START button and the 610 will begin building back the 7.5 second delay.

1. While still in delay, give the remote talent their normal verbal cues.
2. Switch the studio to off-air monitoring.
3. When the verbal cue is heard on the air, push the remote BYPASS/OPERATE button. (This puts the station on-air in real time.)
4. At the end of the live report, push the BYPASS/OPERATE button and then the START button.
5. Switch the studio monitors back to “board output.”

Why do I hear distortion when the 610 Broadcast Audio Delay is activated?

A level increase of this magnitude will increase the amount of compression applied by the limiter by 6 dB. This change will be noticed by anyone sensitive to the station’s sound. Distortion will become evident if the input circuit of the limiter runs out of headroom and clips. Clipping may also occur in other devices downstream from the audio processor in your audio chain (distribution amps, STL transmitters).

On-air talent will invariably accuse the 610 for any degradation in audio quality because the problem will make itself evident when they push the START button on the 610 and begin building delay.

One solution is to convert the input of the device plugged into the 610’s output to a bridging (high impedance) input. If this is done, the console output will switch between two bridging inputs when the 610 cycles between bypass and operate. There will be no significant change in loading to the console output.

Most modern equipment is built with electronically balanced inputs. Transformer inputs are virtually never used anymore. If an input presents a 600-ohm load, it is most likely created by the addition of a 620-ohm resistor across the input circuit. Removal of this resistor may be all that is required to convert the input to a bridging input. Consult the manual, or call the manufacturer of your audio processor, for assistance.

Where can I find a Data Sheet for the 610 Broadcast Audio Delay?

Why does my 610 system level change when I switch between Operate and Bypass?

A few users are surprised with large gain increases when they install the 610 into their audio chain. Here’s why.

The 610 uses a balanced, bridging input. It does not present a 600-ohm load to the output of the device which drives the 610’s input. In other words, your console output is not loaded by 600 ohms when the 610 is in the circuit and operating.

When the 610 is in the bypass mode, a relay connects the output connectors to the input connectors. This is a “hardwire” bypass, a copper path between input and output. This means that when the 610 is in the bypass mode, the console output sees the load of the input circuit of the device connected to the 610’s output connectors. Your console output connects directly to the input of your audio processor anytime that the 610 is not in delay.

If the audio processor input presents a 600-ohm load to the console output, the 610 will remove the load to the console output when it goes on-line. Because the console output is no longer connected to a 600-ohm load, its output signal may rise as much as 6 dB, depending upon the output circuitry.

This level increase will pass through the 610. The input of the audio processor will receive a signal which is 7 dB hotter than when the 610 is in the bypass mode. This is because of the 6 dB gain change caused by removal of the 600-ohm load, plus a 1 dB gain increase inside the 610. We use a heavy duty output driver in the 610. It is able to supply the same output level to either a bridging input (high impedance) or a 600-ohm load. The 610’s output does not drop when it is loaded with 600 ohms. The output drivers of some equipment are not this robust.

Where can I find Schematics for the 610 Broadcast Audio Delay?

Why is there a high frequency roll-off while the 610 Broadcast Audio Delay builds delay?

While the 610 is building delay, the frequency response is down 1 dB at 6 kHz, 2 dB at 8 kHz and 3.5 dB at 10 kHz. Once the 610 builds its 7.5 second delay the frequency response is flat (within 1 dB) between 20 Hz and 14 kHz.