This is a special version of the FS 41501 with balanced input and output.

• Shift frequency continuously adjustable from 1 to 10Hz.
• Increase of 6-8 dB in the stability margin, depending on environmental conditions.
• BYPASS switch (hard-wire bypass).
• INCREASE / DECREASE frequency shift switch.
• XLR input and output connectors duplicated on jack connectors.
• Delayed insertion at switch-on.
• Fast start of operation.