It can vary with the engine. The Bachmann GP-30 was originally (c.1989) part of the upgraded "Spectrum" line, but now is just in their standard line. That being said, the newer ones run much more quietly than the old Spectrum ones in my experience. The HO steam engines released as Spectrum engines (that is, engines like the USRA light 4-8-2, 2-6-6-2, etc....not engines like the old Reading 2-8-0) tend to run very well and very quietly.