If there was one thing King Thorax could admire about Chrysalis, his former ruler and - as much as he loathed to call her this - his mother, it's that she was a great singer. Even when she wasn't in disguise as a pony with an innate talent for singing, her voice always locked Thorax into a state of wonder. Case in point: the Canterlot invasion.
While not every Changeling drone was constantly wreaking havoc and terrorizing the citizens of Canterlot, as there was also a line of defense, Thorax wasn't even performing the latter, at least not honestly. Never much of a fighter, Thorax just stayed in the sidelines, admiring the fresh air and scenery of Canterlot - a welcome change from the gruesome hive few other than the designated love harvesters ventured out of on a regular basis.
Once the invasion was in full swing, Thorax sensed something else refreshing - the beginning of a song, to be performed by the Queen. Upon hearing the first few bars of the music accompanying the song, Thorax flew towards Canterlot Castle to hear her eloquent voice, disregarding the looks his fellow drones gave him.
This day has just been perfect
The kind of day of which I've dreamed since I was small
Every pony I'll soon control
Every stallion, mare, and foal
Who says a girl can't really have it all?
It was simply magnificent. Now, two traits reflected in the song - greed and control - weren't among Thorax's favorites, but they were ones he had been raised around. And with his mother's rousing delivery of the lyrics, he didn't care much about the evil they conveyed. As the music flowed, Thorax sensed a distinct emotion in his queen - joy- perhaps the most coveted one in Changelings besides love. He wanted some of that joy. He wanted to sing. The trouble is, he had never had a song he could call his own.
It's not as if he had never sung a note in his life. He certainly accompanied his fellow drones during Chrysalis' call-and-response drills. That, of course, was under orders. Anyling who didn't comply had a portion of love sucked out of them, never to be returned by the evil queen who ate it.
Singing alone, however was a different story. Historically, the average Changeling did not have the same level of ability as say, a pony, to break into song. Singing required ample energy, which for Changelings, came in the form of love. Chrysalis had been keeping the majority of the love for herself, so she was perfectly capable of starting a number when the situation called for it. When it came time for her drones to sing back to her (not in the same sense as talking back to her), she would supply them with a sufficient amount of love, but was careful not to leave them with enough love to belt out a solo later on, for she saw that as a potential means of rebellion.
But things were different now. Thanks to the courageous efforts of Thorax and his friends, the old authoritarian regime of Chrysalis was overthrown, and under this new regime led by him, love was now shared, rather than swiped and (unequally) rationed. Free expression through song became as integral to Changeling culture as it had long been to the ponies. While songs could convey mean-spirited feelings, as the former Queen's songs typically did, they could also convey love, and potentially spread it. This was one of the goals of the new changelings, even if some were slow to accept it, remaining untransformed until Thorax pushed them into it. While Thorax wanted to be the opposite of Chrysalis as much as he could, he would learn that assertiveness was an essential virtue for a ruler; though he only used it when necessary.
Yet their benevolent ruler wasn't joining in on this new vocal trend, as much as he wanted to. This wasn't so much out of shyness as it was a lack of confidence in his vocal abilities. Aside from his mother, he was sure everyone else he knew sang better. His friend Spike could sing; he learned this firsthoof the day they met when Spike graciously stood up for him in a tear-inducing ballad. Others in the hive could more readily carry a tune - even Pharynx, his once estranged brother.
Thinking of these two important figures in his life gave him an idea. He knew Pharynx had a natural capacity to lead; if it weren't for the new direction the Changelings were taking, he likely would have ended up as Chrysalis' successor. He knew Spike had a natural capacity for singing. If he went to his friend for advice, whilst leaving his brother in charge for the time being, he might be able to gain enough confidence to start belting it out. Perhaps he could also go for some vocal lessons if his singing was as subpar as he assumed.
Finding Pharynx, the King informed him of his plans. "Pharynx, would you watch over the hive for the next day or two? I'm heading off to Ponyville to visit Spike."
"Uh, sure? But why?"
"I want to get over my reluctance to sing by myself, and I think Spike, and maybe the others in Ponyville, could help me."
Pharynx may have had the knack for keeping control, but understanding his brother was still a work in progress.
"Once again, you're getting worried over something so basic. Geez, bro, you haven't changed since we were nymphs!"
"You know that isn't true! But either way, I just feel that if I do something this ambitious, I ought to do it well."
"Ugh, Princess Twilight's rubbing off on you with those prefectionist tendencies of hers."
"How do you know that about her, anyway? You two have never met."
"With all the yapping on about her you do, I don't have to have met her."
Thorax didn't think he spoke of the Princess that often around the hive, but whatever. Knowing Pharynx agreed to oversee the hive at the start, he didn't see it worth arguing with him any further. Bidding his brother farewell for the time being, he took off, bound for Ponyville.