[semlar]

You could try something like this..

local Channeled = { ['Fists of Fury'] = true }
local Instants = {
    ['Blackout Kick'] = true,
    ['Expel Harm'] = true,
    ['Flying Serpent Kick'] = true,
    ['Grapple Weapon'] = true,
    ['Resuscitate'] = true,
    ['Rising Sun Kick'] = true,
    ['Spear Hand Strike'] = true,
    ['Spinning Crane Kick'] = true,
    ['Tiger Palm'] = true,
    ['Touch of Karma'] = true,
    ['Zen Meditation'] = true,
    ['Paralysis'] = true,
    ['Fortifying Brew'] = true,
    ['Touch of Death'] = true,
    ['Tigereye Brew'] = true,
}
 
local f = CreateFrame('frame')
f:RegisterUnitEvent('UNIT_SPELLCAST_CHANNEL_START', 'player')
f:RegisterUnitEvent('UNIT_SPELLCAST_SUCCEEDED', 'player')
 
f:SetScript('OnEvent', function(self, event, unit, spellName, ...)
    if (event == 'UNIT_SPELLCAST_CHANNEL_START' and Channeled[spellName])
    or (event == 'UNIT_SPELLCAST_SUCCEEDED' and Instants[spellName]) then
        PlaySoundFile('interface/addons/hokutonomonk/sounds/' .. spellName .. '.ogg', 'SFX')
    end
end)

It's drycoded so let me know if it doesn't work.