Parameters for turbosound driver / alternative
I'm trying to get the thiele small parameters (specifically Bl, Mms, Fs and also voice coil diameter) for the midrange driver in the old Turbosound tfl670 (floodlight). I have the chance to buy a pair of the horns, with axeheads, with these drivers and the low mid drivers removed (used as spares by a PA company I understand). Hence I would have to come up with 2 new high mid and 2 new low mid drivers. Whether they are even available now I am not sure, and doubt. Certainly they are above my price range, looking at how much they used to go for.
What I would like to do is convert some standard speaker to use in these horns if its possible - I think that mechanically I could do this but how would it perform? I would like to be able to predict how well they would perform before going through the whole project in case its a total failure.
My main concern I think is whether the mass breakpoint of a different driver would curtail the response at too low a frequency. Hence if I can get some figures for the old speakers I can hopefully predict how well they would work.
Unlikely that anyone has this information I realize, but comments would be much appreciated. Also if anyone could suggest replacements for these 6.5 inch drivers I would be very interested to hear these ideas.