I have these speakers and not only do they put out tremendous bass, but also clean and fast bass. They are powered by the Rogue Audio Cronus tube amp and the combo sounds magical with the VPI Classic and Lyra Delos cart. I don't agree with opinions these speakers are not tube-friendly. I do agree, however, that impedance matching can help. I believe the nominal impedance of the SR 17.5s is 8 Ohms and switching from the 4 Ohms to the 8 Ohms taps resulted in fuller and heftier bass.
As a few wise responses suggested, the positioning of the SRs is critical. You had them way too close to the walls initially. I'd suggest at least 2 feet from the side wall and 3 feet from the front wall. I faced a big challenge in my set-up as my room is roughly 12'x11' and I knew taming the bass was going to be a problem. In addition to placing the speakers as far from the walls as I could while maintaining the imaging and the soundstage I preferred, I also treated the room with some dyi fiberglass panels. I bought a box of Owens Corning series 700 2'x4' fiberglass boards from a local insulation materials shop. Ten boards cost me $140. If you have a big supplier in your area, you can get them as cheap as $83. I then bought 2'x4' sheets of particle board from Home Depot and some fabric from a fabric store. It took me about 30 minutes with the help of my girlfriend and a staple gun to make several acoustic panels. I made a few with 2 fg boards per panel to make them more effective in absorbing bass. Considering the size of the room, unavoidable proximity of the listening position to the back wall and the amount of bass these monitors produce, the sound is superb. Speaker placement and room acoustics simply cannot be overstated.
As a few wise responses suggested, the positioning of the SRs is critical. You had them way too close to the walls initially. I'd suggest at least 2 feet from the side wall and 3 feet from the front wall. I faced a big challenge in my set-up as my room is roughly 12'x11' and I knew taming the bass was going to be a problem. In addition to placing the speakers as far from the walls as I could while maintaining the imaging and the soundstage I preferred, I also treated the room with some dyi fiberglass panels. I bought a box of Owens Corning series 700 2'x4' fiberglass boards from a local insulation materials shop. Ten boards cost me $140. If you have a big supplier in your area, you can get them as cheap as $83. I then bought 2'x4' sheets of particle board from Home Depot and some fabric from a fabric store. It took me about 30 minutes with the help of my girlfriend and a staple gun to make several acoustic panels. I made a few with 2 fg boards per panel to make them more effective in absorbing bass. Considering the size of the room, unavoidable proximity of the listening position to the back wall and the amount of bass these monitors produce, the sound is superb. Speaker placement and room acoustics simply cannot be overstated.