This preamp replaced the famed Aloia 11.01. The room correction (frequency response and time) need in some room/speaker combinations makes this a no brainer. I had 2 11dB dips and 1 10dB spike from 2KHz to 20hz. This is the region that requires the most correction. You wouldn't believe how different the presentation is with application of one curve vs another. I agree with Jvogt in his description of the performance - much better balanced bass, improved imaging, depth/width of soundstage. Mike