In terms of the guitar tones you can create with AMPLIFi and Spider V, there's virtually nothing between them - both are hugely flexible and sound awesome. But there are some big differences in how Line 6 have designed them...
The AMPLIFi 30, AMPLIFi 75 and AMPLIFi 150 have true stereo hifi-quality speakers and you can stream music via Bluetooth from your iOS or Android device - either to listen to, or to play along with. You also use your iOS or Android device (via Bluetooth) to build and customise your tones.
For recording, every AMPLIFi model doubles as a USB audio interface so you can easily record into Cubase, Logic and other DAWs.
Line 6 designed AMPLIFi to look great in the living room, music room or bedroom - and nothing like a traditional guitar amp. (There's also the AMPLIFi FX pedal board if you already have a great set of speakers.)
Spider V doesn't have a Bluetooth connection (you connect an iOS or Android device using a USB cable) and most of the models are mono rather than stereo.
But you can create and edit tones on the amp itself, the main speaker is bigger than on comparatively powered AMPLIFi models (so more bass) and all models from the Spider V 60 upwards have Line 6's Relay wireless guitar system built in - so you just need a compact G10T transmitter to replace your guitar cable.
Like the AMPLIFi range, the Spider V amps also have a USB interface for recording to a Mac or Windows computer - the Spider V amps come complete with Steinberg's Cubase LE software, perfect if you're just starting out.
Spider V is built and designed like a traditional guitar amp - rugged for transport and great on stage.
So, if you're after something that doubles up as a great wireless hifi, looks awesome and you already have an iOS or Android phone or table, AMPLIFi might be the one to go for. If you're looking for something that you use for home guitar practice but also take to rehearsals and/or gigs, Spider V might be the better choice.
