Impedance question??

[Paulonbass]

Hey everyone,

I've got a Crate VFX5112 1 x 12' combo with a 16 ohm speaker loaded. There is an output jack at the back for an extension cabinet and a switch to switch from 16 ohms to 8 when used with another 16 ohm cabinet.

I want to use my extension cabinet only which is an 8 ohm single 12".
Can I unplug the 12" in my combo switch the button on the back to 8 ohm and use that connection to plug the external cab?

Here is a block diagram of this amp, let me know what you guys think.

http://www.flickr.com/photos/21196624@N08/2287916430/

Thanks,

Paul

[Hamm Guitars]

Yes that will work. Jut don't run the amp without a load (no speaker).

[Tarl]

Hey everyone,

I've got a Crate VFX5112 1 x 12' combo with a 16 ohm speaker loaded. There is an output jack at the back for an extension cabinet and a switch to switch from 16 ohms to 8 when used with another 16 ohm cabinet.

I want to use my extension cabinet only which is an 8 ohm single 12".
Can I unplug the 12" in my combo switch the button on the back to 8 ohm and use that connection to plug the external cab?

Here is a block diagram of this amp, let me know what you guys think.

http://www.flickr.com/photos/21196624@N08/2287916430/

Thanks,

Paul

I have the exact same amp and run it as a 3x12 with a cab all the time. To do this the amp should be in the 8 ohm mode (my cab is 16 ohms, same as the amp speaker). The owners manual states that "when a 16 ohm extension speaker is used this switch must be set to the 8 ohm position" also "the internal speaker is not disconected when this jack is in use" When just using the amp speaker the switch should be on the 16 ohm load (as it is set at the factory). If you unplug the internal speaker and only use a cab the amp will actually be looking for a 16 ohm load (same as the internal speaker).....unless you switch to the 8 ohm mode.....so the cab could be 8 or 16 ohm, depending on where the switch is set.