Phono Stage Explained: Why Records Sound Different

What exactly does a phono stage do?

A turntable's cartridge generates a very small electrical signal as the stylus tracks the grooves. That signal is much weaker than the line-level output from a CD player or a phone. It also has a deliberately altered frequency balance that must be corrected. The phono stage performs two jobs: it amplifies the cartridge signal to line level, and it applies the RIAA equalization curve to restore the original tonal balance.

Without a phono stage, your amplifier or powered speakers will receive a signal that is both too quiet and too bright, since the highs are boosted and the lows are suppressed on the record itself. You would hear a thin, faint sound. A phono stage is therefore an essential part of any vinyl playback system, whether it is built into your turntable, your receiver, or a separate box.

• Amplification: brings the cartridge output up to line level, typically around 200 to 500 times gain, though exact numbers depend on the cartridge type and design.
• Equalization: applies the inverse of the RIAA curve to flatten the frequency response.
• Impedance loading: matches the cartridge's electrical requirements, especially important for moving coil cartridges.

Why records sound different: the RIAA curve

In the 1950s, the Recording Industry Association of America (RIAA) standardized the way records are cut and played back. This standard, known as the RIAA equalization curve, boosts high frequencies and cuts low frequencies during mastering. That allows longer playing time and reduces surface noise and groove distortion.

When you play a record, the phono stage applies the opposite curve: it cuts the highs and boosts the lows. This brings the audio back to the original flat response that the artist and engineer intended. Without this correction, your records would sound harsh, with weak bass and loud hiss from the surface.

The RIAA is the industry body that maintains this standard today. When you buy a turntable or a phono preamp, the RIAA curve is built into the phono stage, so you do not need to adjust anything yourself.

Built-in versus external phono stages

Many modern turntables include a built-in phono stage, often labeled as a "phono preamp" or "line output." If your turntable has one, you can plug it directly into any line-level input on your amplifier, receiver, or powered speakers. This is the simplest setup, and it is common on entry-level and mid-range tables.

Other turntables do not have a built-in phono stage. They require you to connect them to a phono input on a receiver or an external phono preamp. Some audiophiles prefer external units because they offer better components, adjustable loading, and a cleaner power supply, but a good built-in stage can sound perfectly fine.

If you are not sure whether your turntable has a built-in phono stage, check the back panel for a switch labeled "Phono" or "Line." Also, many receivers include a phono input that bypasses the line inputs and provides the necessary RIAA correction. Read our comparison of built-in vs external phono preamps and phono preamp vs receiver phono input for more details.

• Built-in: convenient, saves money and space, ideal for beginners.
• External: upgradeable, often more transparent, gives you control over loading and gain.
• Receiver phono input: a built-in phono stage inside your amplifier; check if your receiver has one.

How cartridge type affects the phono stage

There are two main cartridge types: moving magnet (MM) and moving coil (MC). MM cartridges produce a higher output voltage and are more common, while MC cartridges produce a lower signal and require more gain and specific loading. Most phono stages are designed for MM cartridges, but many also offer MC settings.

If you use a moving coil cartridge, you need a phono stage that can handle its low output and match its impedance. This is a key consideration when choosing an external preamp. For a deeper dive, read about moving magnet vs moving coil cartridges and cartridge output voltage.

What to look for when choosing a phono stage

When selecting a phono stage, consider the cartridge you use, the inputs you need, and the quality of the components. Look for a unit that supports your cartridge type (MM or MC), has the proper gain and loading options, and offers clean RIAA accuracy. Some phono stages also include a subsonic filter to remove very low frequency rumble.

You do not need to spend a lot to get a reliable phono stage, but better models often provide lower noise and more flexibility. If your turntable already has a built-in stage, you can always bypass it later with an external unit. The best approach is to start simple and upgrade if you feel the need.

For turntable recommendations with and without built-in phono stages, check our budget turntable picks and higher-end turntable picks guides, or look for models with Bluetooth output in our Bluetooth turntable guide guide.

What to pick for your use

Questions

Do all turntables need a phono stage?

No. Turntables with a built-in phono stage send a line-level signal and can be connected directly to any audio input. Turntables without one require you to connect them to a phono input or an external phono preamp.

What happens if you play a record without a phono stage?

The audio will be very quiet and will lack bass, with overly bright highs. You might not hear anything at normal volume, or the sound will be thin and distorted.

Is a phono stage the same as a preamp?

Not exactly. A phono stage is a specialized preamp that handles the cartridge signal and RIAA equalization. A regular preamp usually boosts line-level signals but does not apply the RIAA curve.

Can I use a phono stage with a digital receiver?

Yes, if the receiver has a line-level analog input. The phono stage outputs line level, so you can connect it to any of the receiver's analog inputs, including auxiliary or CD inputs.

How do I know if my turntable has a phono stage?

Look for a switch labeled "Phono/Line" on the back, or check if the turntable has RCA jacks and a ground wire. Many modern turntables with a switch are set to "Phono" by default, so you can change it to "Line" when using a line input.