Christmas Singing Lights

Hi Yes, you can build it with Arduino or ATtiny85 but i would not say that its the best way to do it, especially if you just want to use it for Xmas lights. Its like taking a bazuka for a sword fight. 

Anyways you can look into some of the audio modules which can record and play music right out of the box and is way cheaper like ISD1820 give them a try 

ST offers a new STM8S device: the STM8S001J3 in an SO8N package. It's more powerful than the ATtiny85: same Flash, double the RAM, less EEPROM, better peripherals (ADC, 1x8bit+2x16bit timers, UART, I2C and half an SPI), and at a price of $0.20 it's much cheaper than the ATtiny85. It's even cheaper than the ATtiny13!

ST offers a new STM8S device: the STM8S001J3 in an S08N package. It's more powerful than the ATiny85: same Flash, double the RAM, less EEPROM,better perpherals. and cheaper than ATiny85.