I have acquired a wonderful pair of IMF transmission line loudspeakers but I cannot identify which model I have.
I was sold these as TLS80s but they aren't quite the same:
1. The lower frequency tweeter is not the correct part for TLS80, it looks to be the part used in TLS50.
2. The KEF B139 woofer has a label on it (inside) which suggests is too old as it pre-dates the launch of TLS80.
3. The "aspect control" present on TLS80 and all later large IMF loudspeakers is not present and clearly never has been present.
4. The front cabinet design is closer to a PM than TLS80, in particular the ports at the bottom for the transmission line are incorrect for TLS80.
5. The crossover is not a TLS80 crossover, it's a much simpler design. It doesn't appear to have ever been changed so I don't think it is a home-made substitute.
6. The IMF badge on the front grilles (not shown in photo) simply shows "IMF". By the time TLS80s were made the bade showed "IMF Electronics".
7. The cabinets are slightly the wrong size for TLS80s, the height is about correct but the depth and width are slightly different.
8. The front panel which carries the drivers is not detachable, unlike a TLS80 front panel.
Any help with identifying what I've got will be much appreciated. They sound awesome, but not knowing what they are is frustrating.
Thanks
Tim
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