I checked out the prices of some of items that I had bought in last 6 months. My finding:

1. Gas Wars: Current Price: 585, My Purchase price: 503, Purchase Month: April 2014
   
2. Sennheiser CX 180 Street II In-Ear Headphone: Current Price: 749, My purchase price: 696, Purchase Month: May 2014
   
3. D-Link DSL-2750U Wireless N 300 ADSL2+ 4-Port Wi-Fi Router with Modem: Current Price: 2169, My Purchase price: 2028, Purchase Month: June 2014
   
4. Transcend StoreJet 25H3P 2.5-inch 2TB Portable External Hard Drive: Current Price: 8099, My Purchase Price: 7598, Purchase Month: June 2014
   
   I haven't checked the prices of these items in last couple of weeks so I can't say if the prices have been increased specifically for sale or not.

For budget headphone, Sennheiser CX 180 Street II In-Ear Headphone @699/-.

And if you pay with Amazon Pay, you get 10% cashback.

My opinion -

Sennheiser CX 180 Street II In-Ear Headphone (Black), without Mic.

Audio-Technica ATH-CLR100BK In-Ear Headphones (Black)

http://www.amazon.in/Sennheiser-CX-180-Street-II/dp/B00D75AB6I

I have been using mine for almost 2 years now. Good noise isolation and the earbuds are comfortable.

They give you 3 different sizes for the earbuds from which you can choose the most comfortable one.

http://www.amazon.in/Sennheiser-CX-180-Street-II/dp/B00D75AB6I 2 year warranty + works good

May I suggest Sennheiser CX 180 Street II In-Ear Headphone without Mic. If you are looking for an earphone that provides a balanced audio, nice vocals and not too much bass then Sennheiser CX 180 are meant for you only.

Company provides 2 years replacement warranty and moreover they do the replacement genuinely.

Ps. Not meant for rough and tough use as the wire is delicate.
https://www.amazon.in/dp/B00D75AB6I/ref=cm_sw_r_cp_apa_i_T5NIBb1KYVBMV

Sennheiser CX 180
I have been using it for the past 1.5 yrs...good value for money & very durable...sound quality is also good

the best options. That plus 1 year replacement makes it a no brainer.

For headphones, I recommend anything by Sennheiser. I bought a rather cheap one for 700Rs and yet, it works like a charm.

Link

Headphones/Earphones Deal

Sennheiser CX 180 Street II In-Ear Headphone are available at their lowest ever price ₹699.

Sennheiser HD 180 Over-Ear Headphones are available at their lowest ever ₹798.

If you can spend some more, I'd personally recommend SoundMagic E10C In-Ear Headphones, which are at ₹1399. I had bought them from headphonezone about two years back at ₹1980, and they are still as good as they were the first 100 times of listening.

Thanks man, I'll look into buying these. I currently have Sennheiser CX 180 Street II In-Ear Headphone but I'm not sure if these are supposed to be noice-cancelling considering they cost like $15 and it doesn't say so on product details.

1 audiotechnica

2 sennheizer

[Sennheiser CX 180]
(https://www.amazon.in/gp/aw/d/B00D75AB6I/ref=mp_s_a_1_1?ie=UTF8&qid=1505581287&sr=8-1&pi=AC_SX118_SY170_FMwebp_QL65&keywords=sennheiser+-+cx+180&dpPl=1&dpID=31LPmQMJm0L&ref=plSrch).

Ok I've managed to get the microphone working well with the stethoscope by combining the concepts in this one. I used 3.7v lipo battery from my quadcopter project and the sound frequency response is pretty good i used this video to test the frequency response and it is working good.

I've only one female 3.5mm jack so i could only test only one device(earphones or iphone) at a time. I used these earphones with 16ohm impedence. I'm afraid if the connect the two jacks simultaneously in parallel it might drop the volume to half. Is there anyway I can overcome that?.

Thanks a ton again.

Will update on what happened with two female jacks in parallel tomorrow.

Any recommendations on Bluetooth transmitter modules for this?

should i buy Sony MDR-XB30EX or Sennheiser CX180

I would suggest you going for Sennheiser CX-180. They are available on amazon for around Rs 700. Excellent sound quality, better than most of the earphones you will find under Rs 1000 range. I know they are over you budget but you'll be getting 2 years of warranty, that means if they stop working, just go to the service center or courier them and they will replace it on the spot.

I have been using then for over an year now and because of my extensive and rough use, one of the earphone always stop working after like 4-5 months and they simply replace them, without any hassle. Make sure that you have sennheiser service center nearby. They have like 3-4 service centers all over the india(pretty low!)

Link to service center in india- http://servicecentre.co/sennheiser-service-centre-list-india.html

​

Link to the product- https://www.amazon.in/Sennheiser-CX-180-Street-II/dp/B00D75AB6I/ref=sr_1_1?s=electronics&ie=UTF8&qid=1537351578&sr=1-1&keywords=senhizer+cx+180

Absolutely love this product by Sennheiser! Keep losing it, keep buying it.


EDIT: Just realized your budget is around 2K. In that range, you will get much better earphones I am sure.

http://www.amazon.in/Sennheiser-CX-180-Street-II/dp/B00D75AB6I