More information is needed to determine why you are not achieving good sound. What amplifier are you using? The Vandersteen 3A Sig is a very capable and revealing loudspeaker that requires a rather powerful high-quality amplifier that is good into 4 ohms.
Also, source components, preamplifiers and placement can have a significant effect. Try improving the bass by following Vandersteen's setup procedure in the 3A manual. That will help to insure that the bass in your room is as neutral as possible.
Lastly, as mentioned by a couple of previous posts, the system can be improved dramatically in the bass (and in the mids and highs) by adding Vandersteen's 2Wq subwoofers.
Dave
Ultra Fidelis
Also, source components, preamplifiers and placement can have a significant effect. Try improving the bass by following Vandersteen's setup procedure in the 3A manual. That will help to insure that the bass in your room is as neutral as possible.
Lastly, as mentioned by a couple of previous posts, the system can be improved dramatically in the bass (and in the mids and highs) by adding Vandersteen's 2Wq subwoofers.
Dave
Ultra Fidelis