The wiki page for the APU noise channel has a "timer period" table (bits 0 - 3 of $400E): http://wiki.nesdev.com/w/index.php/APU_Noise
Do the values in this table indicate the period for the associated timer, or the period reload value for the timer divider, as defined here: http://wiki.nesdev.com/w/index.php/APU#Glossary
Do the values in this table indicate the period for the associated timer, or the period reload value for the timer divider, as defined here: http://wiki.nesdev.com/w/index.php/APU#Glossary