Even if two different equalizers are set correctly, there may be a noticeable difference in the resulting sound quality. Using an equalizer means that the signal must travel through two additional interconnects per channel as well as all of the circuitry in the equalizer itself. This will result in some degradation of the signal. Whether or not this is noticeable depends upon many factors such as the quality of the other audio components in the system, the acoustics of the room, the quality of the equalizer, etc. Purists would scoff at the use of an equalizer, however, keep in mind that every sound track that you listen to has already already been through various equalizers during recording. If you have a really well designed room and are able to place your speakers so that your in-room response at your primary seating positions is within plus or minus 3 db, then equalization may be unnecessary. For the other 99+% of rooms, proper equalization has the potential to dramatically improve the sound.