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SEQUENTIAL/DSI => Prophet => Sequential Prophet X => Topic started by: jwkeys on June 27, 2020, 02:46:31 PM

Title: Unipolar signal page 63 user guide
Post by: jwkeys on June 27, 2020, 02:46:31 PM
I’m trying to find out what a unipolar signal is in this instance
Can anyone explain please ?

An audio signal connected to the rear-panel sequence jack can be used to control arpeggiator (and sequencer) playback. This makes it possible to tempo sync the arpeg- giator to a recorded drum track or other audio source. Audio signals used to drive the arpeggiator/sequencer should not exceed 5 volts peak-to-peak. See “22. Seq Pedal Mode: Normal, Trigger, Gate, T-G—Selects the mode for the rear-panel sequencer jack. This jack requires a unipolar signal. Connecting a bipolar signal can damage this input.” on page 126 for more information about choosing the appropriate mode for
Title: Re: Unipolar signal page 63 user guide
Post by: Derek Cook on June 28, 2020, 12:19:33 AM
I’m trying to find out what a unipolar signal is in this instance
Can anyone explain please ?

An audio signal connected to the rear-panel sequence jack can be used to control arpeggiator (and sequencer) playback. This makes it possible to tempo sync the arpeg- giator to a recorded drum track or other audio source. Audio signals used to drive the arpeggiator/sequencer should not exceed 5 volts peak-to-peak. See “22. Seq Pedal Mode: Normal, Trigger, Gate, T-G—Selects the mode for the rear-panel sequencer jack. This jack requires a unipolar signal. Connecting a bipolar signal can damage this input.” on page 126 for more information about choosing the appropriate mode for

Hi,

Unipolar means the signal should only have polarity in terms of being either a positive or negative voltage, as opposed to a bipolar signal, which can be alternating between positive and negative voltages.

In this case, as per the manual, it should only ever be a positive polarity signal between 0 to 5 volts. If you try and use a signal source that can also go negative, e.g. -5V, then it could damage the input circuit; although, as an electronics engineer,  if that was a risk, I would have put an "idiot diode" or some other form of protection clamp in the circuit.
Title: Re: Unipolar signal page 63 user guide
Post by: jwkeys on June 28, 2020, 04:42:40 AM
Thanks for that
If i take an audio output from an audio interface (presonus 1824) would that be ok?
Title: Re: Unipolar signal page 63 user guide
Post by: Derek Cook on June 28, 2020, 11:11:48 AM
Thanks for that
If i take an audio output from an audio interface (presonus 1824) would that be ok?

Unlikely as that will be alternating above and below 0V.
Title: Re: Unipolar signal page 63 user guide
Post by: jwkeys on June 29, 2020, 02:24:29 AM
Thank you :)