A Spider Jam will handle almost any instrument at bedroom levels. If you take it out on-stage, the situation is slightly different.
The Spider Jam handles microphones like any small PA amp would. It uses the balanced XLR input on front. With the master volume turned right down, you should adjust the MIC LEVEL knob until the clipping light just comes on when you shout into the mic. That sets the correct sensitivity. In practice, I can't get the clipping light to come on no matter how high the setting or how loud I shout into a Shure Beta 58A.
The microphone Channel Volume is set by pressing the INPUTS/LEVEL button twice and balancing the mic level with whatever else is going on. Avoid taking the MIC level above about -10dB or it starts to get noisy.
The MIC EQ and effects are accessed through the SETTINGS TONE button. One press with give you a selection of presets. A second press lets you get at the individual parameters for EQ, reverb, delay and compression. Any preset can be tweaked and will be remembered even after the amp is switched off, however, if you change to a different preset, your tone modifications are overwritten.
There are quite a few options for acoustic guitar and it is possible to get an excellent acoustic guitar tone with the Spider Jam. You can mic-up your guitar and use one of the two Mic Acoustic Guitar presets. There are also two presets for electro acoustic guitars plugged into the AUX input and routed to the MIC channel. If you have piezo or coiled pickups and onboard EQ, you can get an acoustic tone comparable to any dedicated acoustic guitar amp. You can, of course, alter any of these presets if they are not quite what you want.
The other option, is to use one of the guitar amp models. You might want some 'dirt' in your acoustic guitar sound, especially if you play bottleneck blues.
Not much to say here. The options are virtually endless.
You can play a bass guitar through a Sider Jam – quietly. This amp is not a bass guitar amplifier and not only will it not reproduce the low frequencies particularly well, the long speaker cone excursions can wreck the speaker at higher volumes.
Playing a bass guitar through a Sider Jam in a live situation is asking for trouble!
Electric piano works well through a Spider jam. Much better so than most guitar amps. Pianos need a fairly flat frequency response and there are a couple of 'Keyboard' presets in the MIC channel which can be used or tweaked.
Organs are fine too – provided you are not using a bass pedalboard. I have used my Hammond XK1 through my Spider Jam in a band situation and it sounds as good as any keyboard amplifier at reasonable levels.
Same comments as organ. As long as you avoid heavy bottom end, it is fine.
The Spider Jam is totally unsuitable for bagpipe amplification. Bagpipes sound best from a far distance, the further the better. No 75 watt amplifier would be of any use whatsoever at that range.