Mr Knowles was driving his white Mercedes northbound on the M25 near Beaconsfield when his car collided with a DAF lorry at 3.30am.
Ambulance crews and paramedics attended the accident but the 26-year-old was pronounced dead at the scene. The 53-year-old sole occupant of the lorry was unharmed.
Eric Knowles, Seb's father, is an expert on the BBC's Antiques Roadshow.
Seb Knowles lived in Reading and worked as a DJ, holding a weekly radio slot on Time FM before moving onto Wycombe Sound in 2013.
The National Association of Disk Jockeys wrote on Facebook: "All of us would like to send our deepest condolences to the family and friends of Seb Knowles (DJ Sparky B) who tragically died earlier today [Friday]. It's always a tragedy when someone is taken so young. He was a talented DJ who will be missed by all who knew him."
He was Wycombe Wanderers supporter and fans at the club held a minutes applause in his memory before their game against Northampton Town yesterday.
Friends and colleagues have taken to twitter to praise the talented young man.
RIP @SebKnowlesDJ you have been taken from us far too early. You were a true gentleman and it was a pleasure to call you my friend x
— Lynn Underwood (@BadHamble) May 1, 2015
Heaven gained a truly amazing angel today @DeejaySparkyB RIP babe you will never be forgotten and will remain in my heart forever ❤️��’�😇😇😢😢
— Lisa Gee (@xxLisaGxx) May 1, 2015
It's with the heaviest heart that we all cope with the news that @DeejaySparkyB @SebKnowlesDJ passed today :( #RIPSeb pic.twitter.com/E20L2FN4Y7
— DJ Neev (@neevofficial) May 1, 2015
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