I can’t hear a beat frequency against my tinnitus tones, and I really wish I could. (I’ve tuned my guitar with beat frequencies for decades.) The tinnitus tones are very elusive when I try to pin them down with a sine wave, but I can get close by alternating a sine wave on and off while I vary the frequency... the memory of the tone from a second ago has been more reliable than trying to hear if they’re close when overlapping.