As much as our early experiments are burned into my memory, I never cease to be amazed at how tunable a turntable drive system can be, merely as a result of drive belt selection.
With the release of our new drive system, it was time to return to first principles and review variations of this concept, and (why not?) throw a rubber belt into the mix for sake of comparison.
Five different belts were in play:
- A 1/2″ belt made from VCR tape (.001″ thick)
- Our current Kapton belt which is quite rigid , at .003″ thick
- A spliced Mylar belt (our old standby at .002″ thick)
- A belt made from audio cassette tape (thinner, yet)
- A rubber belt sold by a British manufacturer
Spoiler alert. The rubber belt was the big loser.
Broadly speaking, you can group numbers 1-3 in the “good in the right system” category.
The cassette tape belt (#4) was dramatically weaker and the rubber belt (#5) was even more so.
The weaknesses in #4 & #5 were generally in pacing, timing, and delineation of transient attack. Listening to a Cal Tjader album that has been in recent rotation, there was less “motion”, and rhythmic change-ups lost their emphasis. Everything was blurred.
I’ve been using the term “rhythmic intelligibility” as of late. With these two belts, the pulse of the music was compromised in comparison with the other three. If you’re listening to Caribbean jazz, and you’re not “shaking your bootie”, either the music is bad, or something is wrong with the tuning of your system.
System Dependencies, and No Accounting for Taste …
I need to state that I have one customer who absolutely loves the rubber belt, and he was the driving force in my acquiring one. You (in combination with your system) may love it as well, so don’t categorically reject it based on these observations.
Perhaps the most interesting differences were between #1 & #2. In our reference system, it was a toss-up.
In my customer’s system, all three who were present preferred the VCR tape which had a more tonally balanced presentation. The Kapton belt (in his system) had slightly hard-edged transients, and I suspect this may be due to his phono stage.
In a recent blog post, I wrote about phono stage slewing, and how it can mimic other system problems. I suspect this may have been responsible for our preference for the VCR tape in this instance.
In the Pipeline …
It’s time to get some of these options into production, as our current size and thickness Kapton belt may not be for everyone. Only you’ll know what suits you, and you get to choose.
How does it get any better than that?