I'm trying to make an IF filter for my homebrew superhet but I'm having a hard time making an IF filter with a bandwidth wide enough(somewhere between 9-20kHz-ish) for voice reception. My local oscillator covers between 3.3Mhz-6.1Mhz because those frequencies were easy enough to make a stable oscillator at which didn't swing wildly in amplitude/impedance across the frequency range. I would to keep my IF frequency comfortably below the upper limit of my 11Mhz signal generator so if I'm using the difference frequency than I'm sort-of constrained to either 455kHz or a nonstandard frequency like 3.2Mhz(which would give a nice 100kHz-2.9Mhz RF range). It's easy enough to find crystals for these frequencies, but in my experiments the crystals seem to have way too low of a bandwidth(tens to hundreds of Hz)/too high of a Q to be useful anything other than CW or maybe SSB. I have found some ceramic resonators between these frequencies, but the datasheets I have found(like this one) don't seem to provide any helpful information that could be used to find the -3dB bandwidth. How exactly would one go about making a wide-enough IF filter for AM reception below 10.7Mhz+ where most modern receivers keep their IFs??