Start with the source: your quality settings

The single biggest upgrade to streamed sound costs nothing, and most listeners never do it. Streaming apps are designed to be kind to mobile data, so they default to a low or "automatic" bitrate. On a decent home broadband connection there is no reason to accept that. Open the settings menu of each service you use and look for terms like "streaming quality", "audio quality" or "download quality". Set music streaming to the highest available option, and leave video on a lower setting if data is a concern.

Two traps catch people out. First, quality settings often live separately on each device: your phone, your tablet, the desktop app and the web player may all hold different values, so check them individually. Second, many services apply volume levelling or normalisation by default. It is handy when you are shuffling a mixed playlist, but it squashes dynamics and can dull the leading edges of notes. Try switching it off for an album you know well and listen for the difference in punch and quiet detail.

If you subscribe to a lossless tier, make sure the app is actually delivering it. Some services need lossless switching on in a second menu, and some stubbornly fall back to compressed audio over certain connections. A quick check of the "now playing" information usually tells you the file format and sample rate you are receiving.

Why Bluetooth should stay out of your listening room

Bluetooth is a marvel for earbuds on the train, but it is the wrong tool for critical listening at home. Every Bluetooth link re-compresses the audio, because the codec has to squeeze the stream into a narrow pipe. Even the better codecs throw away information, and the compression artefacts tend to land in the upper midrange and treble, exactly where cymbals, strings and vocal texture live. The result is a slightly glassy, flattened presentation that is hard to unhear once you notice it.

There is also a timing problem. Bluetooth buffers aggressively to survive interference, and that processing adds jitter and smearing. You will rarely hear it as a distinct fault — more often as a vague loss of grip and a softer, less defined bass line.

If you must go wireless, use your home network instead. Casting over Wi-Fi — using the built-in casting features of your streaming app — carries far more data than Bluetooth and can pass lossless files intact. Point the stream to a network-connected amplifier, streamer or speaker, not to a Bluetooth receiver. Keep Bluetooth for kitchen radios, portable speakers and podcasts, and it will serve you perfectly well.

Wired is boring, and it works

Cables are unglamorous, but they remove variables. Where you can, run an Ethernet cable from your router to your streamer or network player. It costs a few pounds, takes twenty minutes to route along a skirting board, and eliminates dropouts, buffering and Wi-Fi congestion in one go. If drilling and clipping is impossible, a pair of powerline adaptors or a mesh node with an Ethernet port on the back is a decent compromise.

• Feed your DAC with optical, coaxial or asynchronous USB rather than relying on a headphone socket.
• Keep analogue interconnects short, and keep mains cables away from signal cables where practical.
• Use the 5GHz Wi-Fi band if you must stream wirelessly — it is quieter than 2.4GHz in most homes.
• Reserve the wired connection for the hi-fi, and let phones and laptops fight over Wi-Fi.

If your streamer and amplifier sit close together, a half-metre interconnect of sensible quality is all you need. Spend the money on music instead.

The case for a dedicated streamer

A laptop or desktop computer is a noisy place for audio. Fans, spinning drives and switch-mode power supplies inject electrical noise, and that noise can travel down the USB cable into your DAC. Worse, the operating system often resamples everything to a single fixed rate before it leaves the machine, and system sounds and notifications can interrupt the stream.

A dedicated streamer — a small network player with no screen, no fan and no general-purpose operating system — sidesteps all of this. It receives the file over your network or from a connected drive, hands it to a decent internal or external DAC, and does nothing else. In practice you hear a lower noise floor: darker silences between notes, cleaner decays, a more solid stereo image, and bass that stops and starts rather than smearing into the next beat.

You do not need to spend a fortune. A modest streamer into a well-reviewed DAC will comfortably outperform a laptop into the same DAC, and it will not interrupt your album with a software update prompt.

Get the levels, formats and habits right

Once the chain is clean, a few refinements pay off. Set your streamer or DAC to fixed output and control volume with your amplifier where possible — digital volume controls shave bits off the signal as you turn them down. If you are using a computer as a source, enable exclusive or bit-perfect mode so the operating system hands the file over untouched.

Do not assume higher numbers always sound better. A well-mastered album at CD quality will beat a poor remaster at 24-bit/192kHz every time, so judge each release on its own merits through a familiar pair of recordings. Finally, keep firmware up to date, enable gapless playback for live albums, and give yourself one quiet listening session a week with the lights low and your phone in another room. That habit will teach you more about your system than any upgrade.