Why don't my pc headphones sound the same as the stereo speakers?

It's always a good idea to download and install the latest audio drivers from your OEM computer maker (Dell, HP, Toshiba, Acer) via their support website. The next thing would be to ask, is that if you own these headphones or buy them and test them on your home computer and then return them to the store is not a bad way to go (however, repeatedly doing this in the same stores may get your banned after you return your 15th set of headphones to them in a month!). How much are you spending on these headphones? $25, $50, $75, $100 or more?? Reason I ask is that most of the low-end Headphones you silver-dollar size speakers and are certainly not the same ones used by audiophiles or professional recording engineers. Those are usually in the $150-$1,200 range, and they employ special speaker technology and high-end internal amplifier circuits and custom ASICS chips to deliver sound from the computer that sounds good. Even then, headphones like Koss & Bose still don't sound like a set of Altec-Lansing Voice-of-the-Theatre speakers no matter what. If it doesn't feel like you are having a heart attack with the headphone volume at full, you don't have a top of the line set.

To answer the next question, since W8 came out in 2011, most of the computer makers do not allow simultaneous play of headphones and speakers, period. If you have a laptop, you have no choice there. But, if you have a desktop PC you can do something about that by purchasing a high quality audio sound card that plugs into your Mobo bus such as a Creative Labs SoundBlaster card with Audigy DSP capability. These cards can run from $50-$500 or more, and they offload the entire audio channel of your PC aware from whatever embedded audio chip came with your Motherboard. You can then hook up and run multiple audio sources both analog and digital simultaneously as you are asking about. This is one area where most PC makers fell down many years ago, and decided to do the same thing that Video graphics card makers went and that is if you want high end gaming video quality you need to buy a PCI video card that plugs into the Mobo. Same with audio cards. Each of these represent niche market specialties and the computer makers usually put in middle quality or low-end quality chips into their Mobos to save costs and lower costs to the consumer purchasing their computers. If you want dual headphone-speaker capability you'll need to buy an add-on audio card period. Just like if you want to game; you'll need to buy an expensive gaming add-on card.

With all that being said, I've listened to computer music on the $1,000 headphones and they are still not the same as studio standard external speakers. You cannot get that kind of sound into 1"-2" speakers no matter what technology you use or how much money you pay for them. 36" inch woofers produce sound that can be felt and not heard (extreme low frequency) and that is not reproducible on headphones with tiny little speakers IMO. So what you are asking is simply not possible. Unless you go out and invent new Headphone technology that doesn't yet exist on the planet.

Hope that proves helpful.
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