Jayscen Newby was sentenced in the ACT Supreme Court on Thursday, and with a non-parole term of 10 years will be eligible for release in January 2030.

The 27-year-old had turned up uninvited to his former partner's home in Charnwood after midnight on January 11, 2020, catching her and Frankie Prineas on a date.

He picked up a knife from the kitchen drawer and then cornered the pair in the flat's bedroom from where they were unable to escape and stabbed Mr Prineas 37 times as he backed up against a wall.

The killer, who did not speak at all during the attack, dropped the knife and left, while the woman called triple-0 and desperately tried to stem the bleeding.

Mr Prineas, 27, died on the way to hospital from cardiac arrest caused by the massive blood loss.

Meanwhile, Newby had gone home, shouting at his mum to clean up the blood he had left in his wake.

The jealous and controlling Newby had warned the woman that if he caught her with another man he would kill him.

He left the traumatised woman with a bloodbath.

Newby intended to dominate his former partner, sentencing judge Chief Justice Helen Murrell said.

The court also heard how Newby laughed when on the phone to his mum as she read a news report about the attack.

"Cos it was hilarious," he told his aghast mum.

Newby eventually pleaded guilty to murder, admitting he had intended to seriously harm Mr Prineas but not that he intended to kill him.

He made multiple admissions to friends about what he'd done but continued to blame his former partner.

Once when they fought he hit her in the head with a table, telling a friend he'd hit her hard enough to "put her in her place".

He at one point almost relished the idea of trial where the woman would be in the "spotlight" and everyone could see how she had used him and Mr Prineas as "pawns in her game".

Prosecutors said he showed no remorse, a total lack of insight or empathy or understanding into the impact of what he had done.

At hearing the sentence Newby also showed no emotion.

Dozens of Mr Prineas' family and friends had come to court to hear the sentence handed down.

Many broke down in tears at the playing of a triple-0 call, and hearing the distraught woman tell the operator the blood was coming from "a lot of places" and his "arm is wide open".

At hearing the description of his son's injuries Victor Prineas was unable to hold in his fury and cursed Newby in the dock.

Mr Prineas' family and friends stood and clapped when the sentence was delivered.

"Have a good life, you have a good life my friend," the dad said to his son's killer as he was led to the cells.

Outside court, Victor Prineas expressed shock at the length of the sentence.

"Everything was horrific, the whole thing was absolutely horrific, and this is the outcome."

"Total shock," he said. "Absolutely stunned."

He said his son was a beautiful and special kid. "Cheeky, handsome loveable, respectful, loved by all."

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