The Sennheiser MX270 seems to currently be Sennheiser's cheapest traditional earbuds. I have the MX580 and like it very much. I haven't heard the MX270. If you don't want to splurge for the MX580, you might want to consider the Sony MDR-E828. It has plenty of bass, and imo sounds quite decent at lower volumes, however at higher volumes I can hear a slight bit of distortion when using it. At under $10 though, one can't expect everything. Imo the MDR-E828 probably has the most bass in a traditional earbud under $10. If you can't get the E828, I have a feeling the E818 probably sounds similar(I haven't heard it yet though).
Another cheap option is the JVC HA-S160 headphone. it has excellent sound quality and a decent amount of bass. It is closed, so it does isolate quite a bit. It is quite compact, and my favorite headphone under $20. In the US it is around $12. I don't know about pricing in India.
Last edited by JK98; 02-25-2013 at 10:22 AM.