Amp Line-out question

[dlp777]

I apologize for being not-too-bright when it comes to amplification, but I'm hoping somebody here is more of a genius on this type of thing than me. I've sized down and bought a smaller amp that is easier to transport than my half-stack, both amps have a Line Out on the back that I've been told can be used to send a signal direct to a mixing board. If I run a cable from there to a PA system, do I need to change the impedence (ohms) setting on the amp?

I understand very little about the ohms setting, all I know is 16-ohm for 2 speakers, 8-ohm for 4 speakers, 4-ohm for eight speakers... I'm not even sure that's correct.

I would like to try a line out to a PA to see if it's easier than mic'ing a cabinet onstage, but I do not want to do anything that might make me burn the amp up unintentionally. If anybody can help me, (or direct me to a good website for learning that sort of thing) I'd love the advice. Thanks -

D

[eviltwin]

Originally Posted by dlp777

both amps have a Line Out on the back that I've been told can be used to send a signal direct to a mixing board. If I run a cable from there to a PA system,
do I need to change the impedence (ohms) setting on the amp?

No, line-out will have no effect on the impedance settings. Impedances need to be matched between the poweramp out and the cabinet(s)

I understand very little about the ohms setting, all I know is 16-ohm for 2 speakers, 8-ohm for 4 speakers, 4-ohm for eight speakers... I'm not even sure that's correct.

that all depends on how they are hooked up, two in parallel, or series, two series of two parallel, two parallel of two series, IE:

assume single speaker cabinet = 8 Ohm
2 cabs series 8+8 =16
2 cabs parallel 8+8 = 4 (1/8+1/8=1/4)
2x2 cabs parallel/series 4+4=8
2x2 cabs series/parallel 16+16 = 8 (1/16+1/16=1/

I would like to try a line out to a PA to see if it's easier than mic'ing a cabinet onstage, but I do not want to do anything that might make me burn the amp up unintentionally.

Just make sure that if the poweramp is on, there is still a cab connected and properly matched.

Line-out will be easier, but it will sound differently from miking, even if the line-out includes some sort of speaker emulation.

[chaos731]

Originally Posted by eviltwin

Line-out will be easier, but it will sound differently from miking, even if the line-out includes some sort of speaker emulation.

True enough...though some are better and/or more accurate than others. My Carvin SX200's emulated speaker out jack sounds pretty damned close to the straight up cab sound. I've been thinking about experimenting with simul-recording to two tracks; one track being the mic'd cab (with an SM57) and the other track being the emulated-out direct to DAW and downmixing to a single stereo track, but I haven't gotten around to it. Any significant sound differences would be fairly evident there, but as far as I can tell thus far, it's pretty subtle. Maybe because it's solid state...I would expect that "true tube" dynamics are much harder to emulate in a line out than solid state, but my thinking could be backwards on that point...