You can use the Bose without the EQ but they won't sound as they are supposed to.
If you can't find the Bose EQ for your series 901 then get any graphic equalizer and adjust the sound to your taste. Add bass from about 60hz down. Add high frequencies to taste. Boosting more than 3-6db isn't a great idea.
To use any EQ you will need a way to connect it. Most AVRs will not have a place for you to do that.