The Queen's former choirmaster has been jailed for five years for a 14-year catalogue of child abuse.
Rees-Williams preyed on his victims over a 14-year period
Jonathan Rees-Williams, 55, was convicted in June at Reading Crown Court of a string of assaults, including some carried out in churches.
Jurors heard Rees-Williams, of Bristol, preyed on children from the mid-1970s.
None of the assaults took place during his time at Windsor Castle, where he quit as organist and master of the choir at St George's Chapel in 2002.
Judge Jonathan Playford QC jailed Rees-Williams for five years for the indecent assaults and a further three months, to run consecutively, for possessing 127 indecent images of children on two computers.
The judge told the defendant that he had "fallen from the top to the bottom of society" and described his crimes as "deplorable and offensive to the public".
Rees-Williams, who is married with two teenage children, was described by peers as an outstanding musician.
He enjoyed a successful career in cathedrals, rising to work for the Queen at her Windsor estate in 1991.
But at his trial, five men and one women told of childhood abuse at his hands, in locations including a cathedral organ loft, a church crypt and on public transport.
The "outstanding musician" became organist at St George's in 1991
The former choirmaster of Lichfield Cathedral admitted five counts of indecent assault involving two boys, but denied a further 10 counts against boys and three against a girl.
One of those he admitted, was an assault on a 13-year-old boy, who he invited to his house for a drink of juice after a morning service one Sunday.
In another incident, Rees-Williams pounced on the boy while he was having an asthma attack in bed.
The victim told the court: "He sat me on his knee and I remember thinking 'Oh no, don't do this again, not now'."
The musician also confessed to a string of assaults on a second 13-year-old boy, but claimed it was the child who initiated the sexual contact.
He said he feared the boy would tell someone if he broke off the relationship - a claim dismissed as an "exercise in role reversal" by the prosecution.
After the end of the trial it was revealed that police had found 127 indecent images of children on Rees-Williams's two computers.
After the jury returned its guilty verdicts on the indecent assaults, Rees-Williams entered a guilty plea to one charge of possessing indecent images of children.
He has been banned from working with children for the rest of his life and on his release must register on the sex offenders' list indefinitely.