Sony 7 Open loop versus closed loop

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8.Select the Send request when retrieving samples check box if you want the Sampler Tool to send a request for the sample to the sampler when you click Get Sample.

Clearing the Send request check box requires that the sample transfer be initiated from the sampler, even after you click Get Sample. Typically, pressing the appropriate button on the sampler satisfies this request.

9.Select the Wait for request when sending samples check box if you want the Sampler tool to wait for the sampler to request the sample transfer before sending the sample, even after you click Send Sample. Typically, pressing the appropriate button on the sampler satisfies this request.

Clearing the Wait for request check box configures the Sampler Tool to send the sample as soon as you click Send Sample.

Open loop versus closed loop

Open loop describes a unidirectional communication protocol. When the Open loop check box is selected, the source transmits all data to the destination without listening for instruction from the destination. The destination has no control over how the data is sent and cannot ask for information to be repeated. This lack of feedback makes open-loop transfers prone to error.

The Open Loop check box in the

Sampler Configuration dialog

If the Open loop check box is cleared, the communication protocol is referred to as closed loop. A closed loop allows information to flow in both directions. Using closed-loop transfers, the source sends data in small packets and the destination, upon receiving the packet, either retains the data or discards the packet and requests the data to be resent. Using closed-loop protocol, the source does not send the next packet of data until the destination requests it. This makes closed-loop transfers more reliable than open-loop transfers.

In addition to being less reliable, open-loop transfers are slower than closed-loop transfers, especially when sending samples using the Sampler Tool. This is due to intentional delays placed between data packets to compensate for varying sampler speeds. Closed-loop transfers typically guarantee the most efficient timing between packets.

If possible, avoid using an open loop to receive samples from a sampler. The Sampler Tool cannot control the flow of data packets and there is a high probability that data will be missed.

Tip: Open-loop transfers can be useful when you do not have enough cables to connect both the MIDI input and MIDI output ports.

SAMPLING CHP. 14