The file you're looking for is in DATA/MISSIONS/faction_props.ini

Look for the line that says this

space_costume = sh_male5_head, ku_male_guard_body, comm_br_darcy

If memory serves then it's the comm voice at the end that generates the speech, and you can mess around with these and swap them about so new factions sound almost right

Its in mission/Faction_props.ini, this bit
[FactionProps
affiliation = fc_c_grp
legality = unlawful
nickname_plurality = plural
msg_id_prefix = gcs_refer_faction_fc_c<--------------
jump_preference = jumphole
npc_ship = fc_c_co_fighter_d1-6
npc_ship = fc_c_co_fighter_d7

If you change to other ones you can get them called rogues or alliance which dosen't sound too bad. If you want to get rid of the name completely, use the nomads one:
msg_id_prefix = ignore

Thanks for the info, back to editing.

Nemo me impune lacessit.

I think you can also edit what those factions are saying. This is not really tested yet by myself, but I think it should work. I looked around with the UTF-editor and the .ini files. If you look for example to the liberty navy faction (li_n_grp) in the faction_prob.ini, you see:

voice = pilot_f_mil_m01
voice = pilot_f_mil_m02
voice = pilot_f_leg_f01
voice = pilot_f_leg_f01a

Take for example the voice = pilot_f_mil_m01 and go to the freelancer folder ...../DATA/AUDIO you see some .utf and .ini files. Under them are the male and female voice files => voices_space_female.ini and voices_space_male.ini!

The pilot_f_mil_m01 can be found in the voices_space_male.ini.
There I think you can just delete the entries of those things you don't want the NPC to say! (don't know this for sure it is only a thought .

Example:

[Voice
nickname = pilot_f_mil_m01
script = SC_MLHEAD_MOTION_WALLA_CASL_000LV_XA_%
script = SC_MLBODY_CHRB_IDLE_SMALL_000LV_XA_07

;the following is a sound entry that you could delete.
[Sound
msg = gcs_combat_announce_allclear_01-
duration = 1.414966
attenuation = -6
Priority = -4

But if you also want to put in a new or edit and existing voice sound, you can edit the voice .utf files with the UTF editor. For the example voice it is pilot_f_mil_m01, so you just open up the pilot_f_mil_m01.utf with the UTF-editor. You see some strange tree with nodes that have some codes like; 0x800932CC, 0x8011A604, etc.... Just extract the data from the node and save it. The rename the saved data to .wav and you got a wave file that you can listen/edit with your mediaplayer. After edditing you can put in the .wav files with the UTF-editor again and things should work.

Also an interesting bit of information, that will help me figure out the files for something I am daring a friend of mine to do... add new ship to ship dialogue that is system specific for my mod. No more "We're bound for (blank)" He owns a recording studio and might be able to do it, so I am daring him to try (included in that dare is me buying him some Guinness)

Nemo me impune lacessit.