If you're just starting out, investing in a decent pair of headphones is the best way to get the most improvement out of your computer. Plan on spending around $50-$150. It's important to use headphones that do not require too much power to be driven properly, otherwise they will be under-powered from the relatively weak headphone output of computers and particularly laptops. However, today there are many highly quality headphones that can be driven efficiently from the headphone jack of a computer or laptop. Some laptops sound better than others depending on the sound card's quality and the computer's overall value.
But once you've acquired decent headphones, and you want to know what else is out there, it's time to consider an amp/DAC combo. The next step in creating a high-quality computer audio system is to use a digital USB-compatible headphone amp & DAC (digital to analog converter). These can be in one unit or two separate components.
Dedicated headphone amps & DACs can solve the following problems commonly found with computer audio:
Digital audio over USB connection can offer great sound quality because the music data is sent in "packets" and is then re-assembled at the receiving end, which is the external DAC device. This means that jitter from USB transmission is eliminated as the data received is re-clocked within the noise-controlled environment of the outboard DAC (or 'combo' headphone amp/DAC).
Ah, so you're a mobile audiophile eh? Lucky for you that today you can have a mobile audio system on par with $30,000+ listening rooms right in your laptop bags! A DAC becomes a critical piece in your audio chain at this point ,and we recommend an amp/DAC combination thanks to their compact size. Many little units today offer an impressive array of features, have rechargeable, AA, or AAA batteries, and sometimes in shockingly small packages. Most are capable of driving most headphones under 300 ohms. All of these units have USB connectivity, the most popular and commonly available method for connecting a DAC to your computer.
Many headphone choices are available to you at this point, as nearly all these amps will drive most headphones with ease. Many mobile audiophiles will recommend a high-end in-ear model; impressive universal fit models are available. For the ultimate in audio reproduction, blissful isolation, and supernal comfort, a custom molded in-ear headphone is a very popular choice. Several custom brands are available, with JH Audio leading the pack as the premiere custom provider.
Most headphone listeners will prefer an over-ear style for most home-based applications; since they provide great sound quality, lots of comfort and ease of use, with many choices at varying price points. Choosing an open or closed model will depend on your need to block outside noise.
The good news is that extremely high-quality music reproduction on a computer is within easy reach. Headphone amplifiers and DACs can be purchased separately or are commonly found as an all-in-one. An important consideration for high-fidelity digital listeners is bit rate transmission, with many DACs offering up to 24k/192. Most amps and DACs offer multiple inputs simultaneously connected and easy switching between sources and from headphones to speakers. Occasionally you will have a computer that offers digital output via optical connection, this can be arguable slightly superior to USB, so you may want to consider an optical connection. Balanced drive is also a popular way to obtain extremely high quality audio, and a computer can be an excellent source for balanced transmission.