Assuming they're in proper working condition, healthy caps, and correct component load...................
They're a 70's design specifically for high power, high SPL, sound reinforcement. They won't dig real low, the boxes aren't tuned for it even though the woofers are capable. The same woofers were used for 20hz subs on Pink Floyd's US "The Wall" tour.
Same deal on the top end, HF extension is compromised for high power handling, don't expect a lot of top end sizzle, it won;t be there.
The high power handling allows the use of some EQ to help artificially extend the response. To what extent you can EQ them will be determined by how hard you;re going to drive them. Even in the 70's, pro operators that knew what they were doing would use limiters as an additional line of defense from over-powering.
Clean power with plenty of reserve is the key.
Typically i'd want a good, clean, capable 200-250 wpc amp to drive them such that the amp is never exhausted of headroom or driven to clipping.
2 notes of advice:
don't transport them standing up. The cabinets are mostly plywood. However, for it's density and acoustic properties the entire back panel is made of MDF. The wheel and leg arrangement allows them to tip over backward fairly easily. When that happens, the large "towel bar" type handle will be driven right through the back panel leaving 2 nice fist sized holes in the cabinet, and a useless handle.
Immediately replace the 1/4 inch phone plug inputs with something more appropriate for low impedance/speaker loads. Neutriks would be my first choice. But, a simple barrier strip or binding posts are a perfectly acceptable and solid connection.
