Turntables
1950s onwardsA turntable has an unusually simple brief and an unusually hard one: spin at a constant speed, hold a stylus steady in a groove, and let nothing else — motor hum, footsteps, the speakers themselves — reach the needle.
What it has to get right
Speed accuracy, because a record running fast plays sharp. Speed stability matters even more: slow wavering is heard as wow, fast wavering as flutter, and the ear is unforgiving about both on sustained piano or voice.
Isolation, because the stylus cannot tell the difference between vibration coming from the groove and vibration coming from the floor. This is why turntables have heavy plinths and suspended sub-chassis, and why placing one on the same shelf as a speaker is a bad idea.
Belt drive and direct drive
In a belt drive, a motor sits away from the platter and turns it through an elastic belt. The belt absorbs motor vibration before it reaches the record — good for isolation, at the cost of a slower start and a belt that perishes over time.
In a direct drive, the platter sits on the motor itself. Speed is locked electronically, start-up is immediate and torque is high — which is exactly what a DJ needs and exactly why the format survived in clubs. Isolation then has to be solved by mass and damping rather than by the drive.
Neither is simply better. They are different answers to the same problem, and a good example of either beats a poor example of the other.
The tonearm and the cartridge
The arm has to hold the cartridge at the right height and angle, apply a precise downward force, and otherwise offer as little resistance as possible while the groove moves it across the record.
Because the arm swings in an arc while the groove was cut in a straight line, the stylus is only perfectly aligned at two points across the record — which is what alignment protractors exist to optimise.
A record also drags the arm gently inwards. Anti-skate applies a small outward force to cancel that, so the stylus presses evenly on both groove walls rather than favouring one channel and wearing it faster.
What it evolved into
Very little, and that is the interesting part. A well-made turntable from the 1970s does the same job to a similar standard as a new one, because the problem it solves has not changed. Modern designs add USB outputs and better bearings; they have not had to reinvent the principle.
Names that mattered
Listed because of what they did, not as recommendations. Velorex Music did not make any of these.
Did you know?
- Tracking force is usually between about 1.5 and 2.5 grams — roughly the weight of a paperclip resting on a point microns wide.
- Playing a record with too little downforce damages it more than playing it with slightly too much: a light stylus rattles in the groove.
- 33⅓ is not arbitrary — it comes from fitting a required playing time onto a disc of a practical size at a workable groove pitch.
- A stylus is a wearing part. Manufacturers typically rate them in the hundreds of hours, not years.
Remember this?
Setting one up is a ritual with real steps: level the plinth, balance the arm, dial the counterweight, set anti-skate. People who have done it once tend to remember the first time the arm floated level and stayed there.
Sources & further reading
- Smithsonian NMAH — RCA Victor CP-5203 turntable
- IEEE ETHW — Stereophonic Sound
- Library of Congress — Caring for cylinder and disc recordings
Written from these sources, not copied from them. External links open in a new tab.