Why the cartridge matters more than everything else in the chain

Of all the components in a vinyl front end, the cartridge has the hardest job. It has to trace a wobbly groove no wider than a human hair, turn mechanical movement into a tiny electrical signal, and do so without adding distortion or picking up rumble from the room. A modest turntable with a well-matched cartridge will comfortably outperform an expensive deck with a poorly chosen one. That is why the £100–£500 you spend here usually delivers a more audible change than any other upgrade at a similar price.

Broadly speaking, moving magnet and moving coil are the two families you will meet. There is a third, moving iron, which we will come back to briefly.

Moving magnet: the dependable default

In a moving magnet (MM) cartridge, the coils are fixed and magnets attached to the cantilever move inside them. The result is a healthy output of around 3–6mV, which almost any built-in phono stage will handle comfortably. That high output also means MM designs are less fussy about cable capacitance and hum pickup than their low-output cousins.

Their real trump card is practicality. The stylus assembly usually slides off, so when the tip wears out — typically after 500 to 1,000 hours — you replace just that part for £30–£150 rather than the whole cartridge. For most UK listeners with a turntable in the £200–£800 bracket, MM is the sensible choice.

• Output: roughly 3–6mV, works with standard 47kΩ phono inputs.
• Loading: 47kΩ in parallel with 100–200pF; check the capacitance of your arm cable, as too much dulls the top end.
• Tracking force: typically 1.5–2.5g, so they are forgiving of lighter arms and imperfect records.
• Stylus: user-replaceable in most cases.

Moving coil: more detail, more demands

A moving coil (MC) cartridge reverses the arrangement: the coils sit on the cantilever and move within a fixed magnetic field. Because the coils are small and light, the moving mass is lower, so the stylus can follow the groove's fine modulations more accurately. The payoff is usually better detail, tighter bass and a more open stereo image — but at a price, in both senses.

Output is low. A typical low-output MC produces 0.2–0.5mV, which needs a dedicated MC phono stage, a step-up transformer or a head amp with 60–70dB of gain. Some high-output MCs manage 1.5–2.5mV and will work with an MM input, though they are something of a compromise. Most MC styli cannot be swapped by the owner; when they wear, the cartridge goes away for a rebuild or a trade-in against a new one.

• Output: 0.2–0.5mV (low), 1.5–2.5mV (high).
• Loading: typically 100Ω, sometimes adjustable; getting this wrong costs you either brightness or dullness.
• Tracking force: often 1.8–2.5g, but compliance varies widely between models.
• Stylus: usually a rebuild rather than a DIY swap.

Matching cartridge to arm and phono stage

This is where many upgrades go wrong. The key figure is the resonant frequency formed by the cartridge's compliance and the tonearm's effective mass. You want that resonance sitting between roughly 8Hz and 12Hz — high enough to stay clear of record warps, low enough to avoid audio-band colouration. A low-compliance cartridge on a light arm, or a high-compliance cartridge on a heavy one, will show up as a soft, bloated bottom end or a thin, tizzy top.

Most budget and mid-range arms sit around 8–12g effective mass and work best with medium-compliance cartridges. Ask the maker for the compliance figure in cu (µm/mN) and do the arithmetic: the resonant frequency in Hz is roughly 159 divided by the square root of (total effective mass in grams × compliance in cu). Or simply ask your dealer — most will run the numbers for you in a minute.

Then check the phono stage's gain and loading. MM into an MC input will overload; low-output MC into an MM input will sound thin and noisy. If your amplifier has a fixed MM input, a high-output MC or a step-up transformer is the tidy way forward.

Moving iron and other options

Moving iron designs sit between the two camps, using a small iron armature rather than a magnet or coil on the cantilever. Output is MM-like and the stylus is often replaceable, but the presentation tends to have its own character, with a warm midrange and a slightly softer top. They are worth an audition if you like that sound and want something off the beaten path.

Practical setup and upgrade advice

Whatever you buy, installation matters as much as the cartridge itself. A few things worth doing properly:

• Alignment: use a proper protractor or alignment gauge. A misaligned stylus will wear records unevenly and cause inner-groove distortion.
• Tracking force: set to the upper end of the maker's range for stability on warped vinyl, the lower end for a lighter touch. A digital stylus gauge costs £15–£30 and is far more accurate than a dial.
• Vertical tracking angle: aim for the arm tube roughly parallel to the record surface, then adjust by ear.
• Anti-skate: start at the same value as your tracking force and fine-tune with a test record or by ear.
• Budget split: on a £500 turntable, spending £150–£250 on the cartridge is sensible. Below about £100 you are usually buying a sideways move, not an upgrade.

One last thought: if your amplifier's phono stage is basic, an external one for £120–£250 will often transform a budget MM cartridge and give you the flexibility to move to MC later. Buy from a UK dealer who will fit and align the cartridge for you — that hour of careful setup is worth more than the difference between two closely matched cartridges.