I have both. They are of similar build quality, and both are priced appropriately. The Pro has active electronics that "sound active," if you understand what I mean. I prefer the classic, but can't give you tangible reasons as to why. Both are great players.
Anybody that complains of neck dive doesn't understand the ergonomics of a Thunderbird. Or is just trying to cause trouble.
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I got the three:
Epiphone Thunderbird Standard (MIC one piece "Precision" nut maple bolt on neck with Epiphone TB soapbars)
Epiphone Thunderbird Classic (MII 7 laminate "Jazz bass" nut maple/walnut neckthru body with Gibson TB plus soapbars)
Epiphone Thunderbird Pro (MII 7 laminate "Jazz bass" nut maple/walnut neckthru body with ceramic magnets soapbars)
Standard and Classic are regularly tuned (with Hipshot Gb7 bass extender: D/E, A, D, G and three pivot bridge) to use them with my cover band and eventually at praise/worship
Pro is a fullstep downtuned (with Hipshot Gb7 bass extender: C/D, G, C, F and himass bridge) to use with thrash metal band.
I came close to buy the Gibson Thunderbird a few years ago, just couldn't justify, even if not necessarily expensive (around $. 1,000.00) the difference in price with the Epiphone Classic
They're the same bass and sound, just the craftsmanship cost
differs between the two
So: the Standard is more a cheap instrument
It doesn't mean toy: it just means that I prefer chunkier necks
and the attack of bolt on basses. But the neckdive is horrible: it has no upper horn while the pinstrap lays right where a horn should be. And even if I like the attack of a bolt on neck, Epi TB soapbars are too muddy to appreciate it
The Pro is a more modern take on the Thunderbird concept... the two band equalizer give a somewhat hi-fi snap to it and, tamin' some of trademark mahogany neckthru bass midrange, it allows some serious slappin', thanx to reliable himass bridge.
The Classic IS an import Gibson Thunderbird and its sound and features stay consistent with the "big brother"
I own Standard and Pro in Vintage Sunburst, Classic in Alpine White
I just exchanged Classic and Pro pickguards:
the Classic one comes three ply white/black/white only
the Pro one comes three ply black/white/black only
Bein' a nonsense to me a "blacky" one on the Vintage Sunburst
Pro and much more so a "whity" one on an already white bass,
I placed the "blacky" on the Alpine White Classic, the "whity" on the Vintage Sunburst Pro
Cheers,
Wallace