This patent-pending design has an innovative mechanism in the opening flap, which triggers music or sound to be played each time it is opened. These mailable envelopes allow consumers to add a surprising burst of sound to almost any greeting card. The new envelopes also feature themed designs to create an exciting way to package a greeting card that's not only visually appealing, but also a lot of fun.

"We know that consumers want to create memorable experiences when celebrating special occasions to show their friends and family just how much they care," said Mary McClain, new product concepts creative director American Greetings. "Music and sound envelopes are a unique way to customize a song or sound clip to an already carefully selected greeting card and it adds such a wonderful surprise when the envelope is opened."

Featuring a variety of songs and sounds, the collection has everything to delight recipients, ranging from "What I Like About You" by The Romantics, "You Got It (The Right Stuff)" from New Kids on the Block, and "Happy Birthday" to people cheering and animal noises. The envelopes are perfect additions to any birthday or other festive occasion.

Those kinds of cards cost more for American Greetings to produce, so the company nets less profit per card compared to a traditional greeting card that might quietly pronounce "I love you" without an accompanying musical arrangement.

"We had lower yielding sales, meaning we generated less income as a percentage of net sales. The lower yield was driven by more costly content and lower sell-through. As an example, we sold more cards with higher content-related costs, such as music, lights, and embellishments," Chief Executive Zev Weiss told investors on a call.