I bought this when it was on sale last year and I am very happy with it. The coupon code is what I received by email and not sure whether it is generic.
Excerpt from the email
Hi there,
Until Sunday get yourself 40% off the current ticketed price of a pair of AKG K52 Studio Headphones. Simply present the Exclusive Coupon below & place an order at any JB Hi-Fi Store in Australia or buy online by visiting jbhifi.com.au, adding the product to your shopping cart & entering the Exclusive Coupon code in the space provided at checkout.
Limit of 3 per Coupon. Available online & instore. While stocks last. Offer ends Sunday 14th April 2019.
Code is same as I received so must be generic - $46 C&C