The Spider Jam was primarily designed for the purpose of jamming or practicing at home but if you are careful, it can also be used for small gigs. Rated at 75 watts and with an arsenal of amp models and effects on-hand, it has similar capabilities to quite a few other amps from Line 6 and other manufacturers who make modelling amps. Of course, it also has those looping and backing track facilities that most other amps don't.
One way to use the Spider Jam in a live performance situation might be where you are a soloist or play in a duo and would benefit from some additional backing. The fact that the Spider Jam has such versatile input arrangements means that you can plug-in a microphone, another guitar or even keyboards. Think of the Spider Jam as a compact PA system and you won't go far wrong. Such performances are likely to be in small, intimate venues where massive volume is not required. If you can get your amp up high on a stool, small table or stage, it will help the sound get to the back of the room.
As you won't want to be seen fiddling with the amp between numbers, it is best to preplan your playlist and set up all the necessary tones as presets – maybe in sequential order.
For backing tracks, you can get about half an hour's worth of backing tracks into internal memory after which you would have to load-in the next half hour from SD card during a short break. Unlike tones, which can easily be changed from a FBV footswitch, backing tracks have to be selected using the small LCD screen and the Select knob and 4-way cursor control. This can be difficult to do on-stage and you certainly wouldn't want the wrong track to start playing. I think it is a better idea to put the backing tracks onto another device that is capable of playing single tracks and then stopping – a CD or MP3 player or hard disk recorder.
As your gigs get bigger, you may need more volume or more spread of sound. The two RCA sockets on the back of a Spider Jam can be fed into another amp or PA system. Most PA amps/mixers have stereo RCA jack inputs but you might need an adaptor to convert between RCA and 1/4" jack. RCA cables tend to be thin and unsuitable for sending signals over longer distances.
The two outputs from the RCA jacks pass through a stereo signal from a CD/MP3 player but any guitar, drum or backing track generated from the Spider Jam itself will arrive as two identical mono signals at the RCA sockets. This means that if you are not using a CD/MP3 player, you only need to use one cable from one RCA socket to a mono input on the PA amp or mixer.
The problem here is that the hi-fi nature of the Spider Jam spreads the available 75 watts across a wider frequency spectrum that a dedicated guitar amp would and loses a lot of useful energy in the process. A Spider Jam will not cut through a loud drummer or bass player like a 30 watt valve amp will – in my experience. In that respect, I would not advise using a Spider Jam live for lead guitar in a loud band. It would be okay in a quieter band or for a second rhythm guitar.
The relative complexity of the Spider Jam's controls makes any adjustments tricky to perform quickly and accurately. If you preplan your tones and keep them to a bare minimum, you can flick between them with a FBV pedal. Having to navigate through the tiny LCD screen menus on-stage is only going to cause headaches!
You should also be aware that tones that sound fine in your bedroom will sound quite different when the amp is cranked-up at a gig. Remember that 'loudness' control on your hi-fi. It boosts treble and bass at low volumes to compensate for the ear's inability to hear such frequencies at low volumes. The opposite effect comes into force when you turn your amp up. What sounded like a good balance of frequencies in your bedroom loses all the mid frequencies so you get shrill trebles and deep bass with little in between.
If possible, you should tweak you tones at a pre gig sound check.