Author's Note- When you're listening to the aria, do read slowly, or you'll outpace it and you'll lose the effect. Keep that in mind!

        Now, this took place the next day, just before the concert. This one's less about the concert itself, and more about what made the concert interesting. Calm down, fillies and colts, I'll get to that in good time, but for now, just relax and enjoy.

        A jaunty oboe concerto graced the air surrounding Canterlot Castle. If Casso was not directly mistaken, it was an Antponio Vivaldhay piece, "Il Sole Dea." The Sun Goddess. It surprised him to hear it during the night, but as he flew over the green, he soon learned why.

        There was a garden party of truly massive proportions occurring in the castle's courtyard. Hundreds of ponies mingled in finery that rarely graced even the most grandiose of Casso's performances. Mares and stallions stood around eating hors d'oeurves  and sipping wine, laughing haughtily, whilst the small group of colts and fillies that were present, displeased to be stuffed into the uncomfortable formal wear that their parents had donned them in, stood about with utter looks of dejection adorning their little faces. An old stallion guided guests arriving by carriage to tables, and another directed the carriages themselves.

        As he flew over the party, he could make out a single filly watching the small ensemble of players with wide eyes. "Maybe there is some hope yet for the next generation..." Casso thought with a shimmer of hope. Music had been getting increasingly more complacent in its form for years, save a few artists, such as his friend Ericious Symphonia and the virtuoso cellist Octavia Philharmonica. But they were a dying breed, it seemed.

        The music stirred faint memories in the back of Casso's mind. History of Equestrian Symphony class in the Neighples choral academy. In the year 727 After Nightmare Moon (ANM), Princess Celestia had outlawed all music dedicated to her, any music with her as the subject, or that that referenced her. Publically, it was stated that this was to prevent ponies from passively worshipping their Queen by deifying her in song, but the obsidian pegasus had heard, two mouths removed from the Sun Goddess herself (the two mouths belonging to Princess Luna and Ericious), that in reality, it was because Princess Celestia was terribly bored of hearing about herself. The Edict of Modesty, as it was known, ushered in the Classical Era, and booted out the Baroque. Recently, though nopony seemed to want to dedicate anything to Celestia, so the law was relaxed, and then quietly repealed. Luna joked about enacting her own Edict of Modesty before she refused to see Ericious; he dedicated nearly all of his later works to her.

        Casso alighted on an upper balcony of the castle after talking his way through security and showing them the oak tube in which he held reams upon reams of sheet music. He had opened it up to convince the guards that a it was indeed not full of weapons, and that they could search all they wanted, and never find anything. They let him pass, and thus he flew to Princess Luna's balcony. He could see from outside her room that her trappings were dark blue velvet and satin; opulence of the old school. He tapped his hoof lightly on the door, which flung open towards him, nearly knocking him off the balcony. A very annoyed alicorn trotted out onto the balcony. She caught sight of him and stared at the pegasus with narrowed eyes and a pouting lip. She knew why he was there.

"Casso Dolcespetto," she said softly without a change in expression.

"Your majesty, I just have a delivery, then I'll be out of your mane—" Casso began.

"It will be simply more than that, We expect," the Moon Goddess quipped. "Or else he wouldn't have sent a songbird." She turned and trotted back into her luxurious chamber. "Come in," she beckoned flatly.

        Casso followed her, unsure of how to react. He expected that she might recognize him from various operas or concerts he had performed in, hoping it might give him even the slightest amount of favor, for Ericious's sake. He hadn't anticipated this. She walked to the desk at the end of her bed, a candle illuminating leaves of paper and a quill, along with some sort of lantern.

"Come here," she commanded sternly.

        Nervous, Casso obeyed. As he got closer to her, he could make out notes and a staff on the stack of parchment. He unconsciously began to study the notes, but they were whisked away from his eyes before he could make out any detail. Princess Luna levitated the sheaves directly in front of his face, startling him immensely. His wings shot out to their full length; he was on edge to begin with, but the sudden motion put him over the edge.

        He struggled to fold them as quickly as possible; it was improper for a pegasus to show his wings in front of a lady, least of all a princess, unless he was flying. Luna's expression remained stony.

"Sing," she said bluntly, a little more loudly than the average pony.

"Pardon, your majesty?" Casso said, frightened and flustered all at once. Her expression softened slightly.

"We've been working on something, and the palace guards can't hold a tune to save their lives," she said gently. "We need somepony to provide the baritone."

Casso squinted at the sheet music she held in front of him. "I, um—"

"We will give you a lead-in," she said, her facade completely melting, revealing a warmer, gentler mare. "Just follow along with the music."

        She leaned her mouth over the glass vessel, which Casso had previously assumed was a lantern, and her horn began to glow a dim blue. The vessel began to glow as well, and the princess began to sing.

        Casso could immediately tell the vessel was a device for splitting the acoustics of her voice, for it split into an alto, tenor, and soprano all at once. The tenor seemed to resonate for far longer, creating the illusion that there were multiple voices singing the same tune. It was like nothing Casso had ever heard. It was more than just that; the acoustics of the glass seemed to work like a ventriloquist throwing her voice; Luna's voice seemed to come from all directions, piercing, but not louder than any normal singer. The sound of her aria resonated deep within his chest cavity, in a deeper space than he knew existed. When Luna began to graze the highest notes of her range, Casso felt as if he was fit to burst like a crystal glass shattered by a vocalist as a party trick. Everything Ericious had told him about her suddenly made sense. The feathers on his wings began to vibrate back and forth like his tympanum, and he felt a feeling of supreme bliss. He was so blissful, in fact, that he nearly lost his place on the sheet music. It was only when Luna slowly lifted her head away from the resonance glass that he snapped back to reality, and began to sing his own part.

        His part of the aria was simple; ostinato arpeggios written to accent the sweetness of a stallion's voice, rather than to be consciously-grabbing. The resonance glass was filled with what amounted to a mist of the former aria, providing what sounded like an ethereal choir from the background. Luna's natural voice, though was more stunning than her magically-altered one. He felt a strong feeling of pleasure along his spine ; an intense frisson he had never felt before. His wings felt as if they weren't paralyzed from sheer overstimulatory pleasure, they would have shot out to their full length. Even his hooves felt warm and full of blood. He had sung in hundreds of choirs, orchestras, and ensembles, but musically, he had never felt so whole as to be an instrument of Luna. Even  when he came to the low notes, which he typically had to force out with some difficulty, Luna's voice seemed to act as a siphon, pulling out the notes with ease.

        When Luna changed notes, the residual sound seemed to combine into a beautiful chord; she always changed to the note's fifth when she let her voice resonate. But what struck Casso was that her voice had no rough spots. She could sing fluidly with no slurring of the notes to provide the illusion of a continuous breath of music. She took breaths, but when she exhaled, her lungs made no quarter against the air around them, as if she was dealing with a lighter gas than air. It was as if she was singing in vacuum. As the song ended, and Casso was brought towards the upper end of his range, a soft falsetto, he was left breathless, and thoughtless. It was the most beautiful thing he had ever heard.

        He looked up from the sheet music, and stared at the alicorn in awe. He fought to stop himself form laying prostrate. She was a Goddess. He couldn't find tears to cry, nor could he speak to express his joy. He just stood, too awed even to tremble, and looked at Luna.

"It could use a little more dynamic, dost thou think?" she asked, off-hoofedly.

Casso tried to make a sound, but he couldn't.

"We think We might start over; this isn't sounding quite how We wanted it to," she remarked.

It was the most beautiful thing he had ever heard, and she tore it down like it was nothing.

"It was... Rapture," Casso forced himself to say. His own voice sounded so ugly.

"That?"

"How did you sound so—"

"Smooth? We get that quite frequently. It's the Traditional Royal Canterlot Voice! Speaking in VOLUME strengthens the lungs!" she bellowed cheerfully. Casso was coming out of shock, now, and finally was able to form coherent thoughts.

"That was... Beautiful. What do you call it?" he asked, still overawed, though not physically incapacitated.

"Oh, it doesn't have a name," she said, either oblivious to his reaction, or accustomed to the sort. "It wasn't anything special; We were bored this morning, and We thought We'd put something together for Dear Sister's equinox celebration. Thou sounded wonderful thineself; We wish We had another two just like you," she remarked coyly. "Ericious's praise was well-deserved."

"...Likewise," was all Casso could manage.

"Now, you came to see Us about something?"

"Yes, yes," Casso snapped back to the task at hoof. He had nearly forgotten the oak tube. "In here,
he said delicately. "Is the original score for Ericious's concerto suite tomorrow."

"Why did he will for Us to have it?" Luna enquired, suspicious.

"Because, your majesty, he's afraid you will not like it," Casso said softly.

"And what does Our opinion matter? He never paid it any heed before." Her gentle tone turned to passive poison.

"Because," Casso said. "He loves you, still."

"Because because because! Having a reason for something does not make it valid through ontological proof!" Luna snapped.

"He feels that the music is beneath you, and he doesn't want you to think less of him," Casso said, growing slightly bolder. "He values your opinion very much."

"Then why did he write it?"

"It was not meant for you. Captain Becker, I'm certain you know of him, asked Ericious for specifics within the piece that he couldn't deny!"

"And what of these specifics?"

"He knows you'll be in attendance tomorrow night, and he does want you to hear the concerto... But he offers the unaltered score without the requests added, and he feels it to be a much more appropriate piece for your ears."

Luna turned away for a moment, looking angrily at a spot on the wall as if trying to give to give the death glare to an Ericious who was not there.

"He would send a songbird!" Luna growled to herself. "Your friend is a wily drake. We will keep the score in mind after the concerto on the morrow."

"Thank you, Princess," Casso said softly. He turned to fly out of the room and back to the Ericious's villa.

"Princess?" he asked, pausing for a moment. She looked at him impassively with a neutral expression.

"Would you..." he veritably choked on his words. "Would you... Like to sing another duet sometime?"

Luna's expression remained stoic for a moment, but broke into a warm smile.

"Certainly. We would like that very much. It was good to have thee lend the sweetness of thy voice to the harsh gratings of my own," she giggled coyly.

Casso nearly went walleyed with anticipation. He would get to sing with Luna again! He flew out of the room, shouting back a clumsy 'Adieu, Princess!', and soared off towards the mountains, hardly noticing the garden party nor orchestra playing beneath him. He felt pleased with himself; he had helped his friend, and found a voice he loved more than life itself all in one night. Ericious could fool about with Luna, for all Casso cared; he just wanted to sing with her.