I am starting to experiment with some piezo strip pickups, which need to be loaded with about 10Mohm or higher.
1) how would I modify the input impedance on the FET DI?
2) could this be made switchable?
FET DI impedance mod?
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Re: FET DI impedance mod?
Easy the two 2M2 resistors marked with a * work in parallel to make 1.1Meg input impedance.prhunt wrote:I am starting to experiment with some piezo strip pickups, which need to be loaded with about 10Mohm or higher.
1) how would I modify the input impedance on the FET DI?
2) could this be made switchable?
Changing both of them to 200Meg resistors would make 100Meg input impedance.
If you fit the highest value resistors you can then switch low impedance resistors directly across the TRS jack tip and sleeve to lower the impedance.
eg set with 2 x 200Meg to get 100Meg and switch 1Meg across jack to get 1Meg input etc.
Joe
JLM Audio
Capturing Audio without Injury
JLM Audio
Capturing Audio without Injury
Re: FET DI impedance mod?
Perfect! Thanks Joe
Paul
Paul