First time GHETTO BLASTER used? September 10, 1985 Philips Ad

Was it really a first time? Hmm. Interesting..

 

I doubt whether any manufacturer ever used that term, as it wouldn't appeal to a significant proportion of potential buyers, such as my classical music loving, close to retirement colleague back in 1981, who having bought one upmarket Sharp "bought another one for the bedroom".
If you look that was actually a competition no doubt written by people at Smash Hits who were trying to look as if they had street-cred.
In the UK another term used (quite recently, and in a derogatory way by a different colleague) is a "Brixton Briefcase". I did include a link to UrbanDictionary but having read through it decided it had no place on this forum. You can always Google it if you want to be appalled.

 

Yes but it is a magazine competition, not an advert. Admittedly Philips probably gave them the prizes but they wouldn't have much control over the competition itself.

That reminded me of an infamous competition in Computer Shopper who always gave away the equipment they reviewed as prizes.
Hone a scathing review of a PC and concluded "It would only be a bargain if they gave it away", a few pages later the same PC was being offered as " This month's star prize worth £1000".