A stylophone is a synthesizer, though.
And they used it on Seven Seas of Rhye.
If I listen to bands who used synthesizers, like Genesis for example, I wonder if Queen didn't use them because they didn't like them or they didn't know how to operate them. I'm not a synth-whizkid but it seems to me that Queen started to use synthesizers when they started to add pre-programmed sounds to it.
Sebastian · Member since
Synthesizer: 'an electronic instrument (usually played with a keyboard) that generates and modifies sounds electronically and can imitate a variety of other musical instruments.' synthesiser. (n.d.). WordNet® 3.0. Retrieved March 23, 2010, from Dictionary.com website: http://dictionary.reference.com/browse/synthesiser
Stylophone™ /’st?ilofoOn/ n. Also S-. M20. [f. STYLE n. + -o- + -PHONE. Cf. XYLOPHONE.] 'A miniature electronic musical instrument producing a distinctive buzzing sound when a stylus is drawn across its metal keyboard.' (The Oxford English Dictionary, 1993)
How does it work? 'With the original Stylophone, touching the stylus to the metal plate of the keys would close a circuit with a voltage-controlled oscillator, creating the distinctive, primitive buzzing tone. (guardian.co.uk, Monday 6 July 2009 16.27 BST)
So... unless a stylophone modifies sounds electronically, it's not a synthesiser.