Turntable Drive Mechanisms, What Makes Them Different?

The various turntable drive mechanisms.

The focus on this article will be about the mechanics of the various turntable drive systems. Like with most things of this nature, what sounds best is usually best left up to the user’s own preferences. The goal of all the types is to deliver the best sound while minimizing motor vibrations. There is a school of thought out there for each type (again personal preference.)

There are three types of drive mechanisms that are standard in the industry (there are also plenty of specialized systems out there for the niche market). The most common are: Idler (sometimes also referred to as a rim drive), belt drive and direct drive.

Idler Drive Mechanism

The Idler drive has a motor in which the rubber wheel is pushed up against it, and the other side of the rubber wheel touches on the inside of the turntable platter causing it to rotate. These were extremely popular, and audiophiles still consider them the best option on higher end systems. Over time and with heavy use, the idler wheel tended to develop a flat spot (the wheel itself was replaceable). When this happened, an audible thumping sound could be heard. This wasn’t as noticeable until the development of ported speaker systems that were able to produce lower frequencies. The infamous ‘rumble’ could be heard from the idler style systems. To compensate, sound systems introduced rumble filters that, if enabled, helped to filter out the low rumble, at the cost of some bass frequencies.

The Belt drive was the next evolution to produce a mechanism that would deliver less rumble than the idler mechanism, improve speed stability, and reduce the tracking weight needed for cartridges of the previous system. Improvements have been made over the years to this design to separate the platter from the motor chassis to further isolate any rumble/vibration that might be introduced into the playback as well as spring/weight mechanisms to further improve the overall playback and sound fidelity.

Example of one of the many variations of belt type drive systems.

This is still the preferred implementation by most audiophiles. So what are the downsides to a belt driven system? Well, the belts do wear over time and have to be replaced. They didn’t bear well to stackable setups (where you could stack 5 records on a spindle at a time, but that will be a whole other article). Most audiophiles prefer the single record at a time playback functionality. Given that belts wear out, most sites recommend replacing it every 3-5 years.

I myself still have a turntable that I purchased in 1994, and I’ve only ever replaced the belt once so far in all that time. Your mileage may vary.

The Direct Drive system invented around 1972 by Technics was a further improvement in the turntable evolution.

The direct drive system is exactly what it sounds like. The motor is directly connected to the turntable shaft by a series of yokes and magnets. You may have heard of the term of “quartz lock” for direct drive systems before. This was an added timing device (like a quartz watch) that locked the drive into exactly 33 1/3, or 45 rpm speeds.

Actual Direct Drive Mechanism

This was one of the main selling features of the device along with that there was no belt or idler wheel to wear out over time. They were fairly quiet, and there is still an ongoing debate between belt and direct drive enthusiasts as to which is better to this day.

However, there was soon to be a whole new emerging musical style that would really take advantage of this type of drive mechanism.

With their constant RPM as well as quick spin up times, direct drives became the mainstay of DJ’s as well as famous of DJ’s who used them for scratching records. Not as in destroying the records, but to get that famous Hip-Hop/Rap scratch sound. These turntables allowed for the back and forth movement without losing speed much more easily.

Now, if you own a direct drive turntable and want to scratch a record, keep in mind unless you have a needle/cartridge that won’t skip out of the grooves, it’s not a recommended action to try. There are DJ needles out there, such as the Shure M44-G and the renowned M44-7 that are recommended for this. However, that will be explained in more detail in another article.

So, in the end, which is the best mechanism to purchase to play my vinyl records? Well, I would recommend if you have the chance to try out at least belt drive and direct drive. Idler drives are a little harder to come by. If you’re a DJ, absolutely try out the direct drive system. For most of us, the belt drive system is more than adequate.

At the end of the day, it’s what you can afford/willing to spend, and your own personal tastes.

Dig this article? Check out the full archives of The Technical Corner, by Joel Andrews here: https://vinylwritermusic.com/the-technical-corner-archives/

Published by Joel Andrews

Originally from New Brunswick, Canada, Joel started to really collect vinyl at a time when people were practically giving it away as they moved their collections over to CD. It became clear that he had a strong penchant for how things work when his father arrived home one day to find four-year-old Joel had completely disassembled the family turntable! Joel purchased a turntable when there were only two models left on the shelf, which is still in use today! Joel is into a wide variety of genres, everything from Jazz to Metal and everything in between, and his love for how things work has never faded; it led to an electronics path in college and then computers. His focus has always been on: how do things work, and why?  What led to design decisions, how were things improved upon, why did some formats fade while others remained? These days, Joel works as a cloud consultant in Toronto, Canada but still finds time to tinker with electronics and electronic repair when he can.

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