The people reading Electronic Musician where the ad was placed are heavily into MIDI, not so much GENERAL MIDI. Huge difference. Huge huge difference. Not mentioning midi capabilities would be a crime, my opinion.

The readers of Electronic Musician, however are probably not going to pay any attention to that advertisement nor the text behind the ad.

Electronic Musician in my opinion, is aimed at indie rock and electronic dance music. You might get some attention from the indie rock folks, but the EDM folks, zero.

Put the ad in American Songwriter, where you have people composing and need the backing band, and magic might happen there.