#1
I love my Boss GT-8, but it does not sound great through my spider amp as you can imagine. I'm thinking of buying either an active PA speaker or floor monitor for a more transparent tone and let the GT-8 do the work.

These are the two I am thinking about.

http://www.gear4music.com/PA-DJ-and-Lighting/180W-10-Active-PA-Speaker-by-Gear4music/ACI

http://www.gear4music.com/PA-DJ-and-Lighting/Behringer-F1220A-Eurolive-Active-Wedge-Monitor/AM4

Any ideas or recommendations?
#3
Why don't you get a new amp and use the GT-8 through its clean channel?
Squier "VMC" Stratocaster
PRS SE Singlecut
tc electronic polytune
CMAT MODS Signa Drive
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Ampeg GVT52-112
#4
Because looking around, GT-8 users seem to get better results without using an amp because the GT is capable of doing all the tone work. But not many people said which speakers they use.
#5
I can tell you that Mikael Akerfeldt, for example, used a GT-8 through their Laney amps (nowadays he uses a GT-10), and they have one of my favourite tones ever.

Anyway, you could try to find a Crate Powerblock and a cab with nice speakers.
Squier "VMC" Stratocaster
PRS SE Singlecut
tc electronic polytune
CMAT MODS Signa Drive
Blakemore Effects Deus Ex Machina
DIY gaussmarkov Dr. Boogey
EHX Small Clone
Mooer ShimVerb
DIY Beavis Devolt
T-REX Fuel Tank Chameleon
Ampeg GVT52-112