dissapearing vocal channel?

[Aurality]

Just built some lampizator P17 open baffles using Raal Ribbon tweeters instead of the SABAS,
but still using everything else in that design i.e SABA mids and standard crossover.


The speakers sound great, but on some material the vocals seem to dissapear in the mix somehow,
quite distant and thin sounding and not very present. switching the phase on the mid helps on some
tracks but then I end up needing to reverse it again on others... on simple accoustic guitar and vocal
it appears normal, thick and upfront.. but sometimes when there is more instruments in the mix the problem happens,
vocals appear thin and distant again, seems more than a little EQ would sort out as all other instruments
in that frequency range appear fine and 'up front' even the snare appears to be ok as far as I can tell it
just seems to be an issue with vocals... could this be an effect of out of time mid and tweeter?
not done an impulse response test yet..

Very new to this, so kind of at a loss at the moment.

Thanks

[Andersonix]

I don't know what you've made, but sometimes higher resolution speakers show oddities in the recording.

[pos]

Looks like phase opposition in some (or all?) drivers. Try testing your phase with a monophonic pink noise signal. To factor out the room, place the two speakers close one to another.