Where do I look for that dark, deep tone?

[Clouz]

i have yet to find a bass that has a darker deeper tone than my gibson explorer bass. it is a 2012 limited run in tobacco burst and has thunderbird electronics/pick ups in it. i used it to play all of the C# tuned songs that black sabbath played on their first 6 albums. i used a set of 130 strings on it to compensate for the lower tuning.

not a very good recording but it is what it is. i played through a heritage SVT

 

[Semion N.]

UPDATE:

I received the flats that you guys recommended. At first I was deeply disappointed - as while almost all strings sounded fine, E was kind of weak and quiet. Then I plugged in my headphones and realised my combo can't handle all this BASS

So, first of all, thank you guys. My new bass sounds wonderful now. Now I just gotta sell the Cort and get a new combo. Too bad bassists are kind of sparse in Israel...