Good Tweaks and Bad Tweaks

Besides cables, tweaks are the main focus of most of the bile aimed at “The High End” by the snake oil police. While it can be successfully argued that most snake oil posts are nothing more than the sour-grapes scree, there are some problems with “tweaks” be they “resonance control devices” or AC power filters. Unless you actually have a sonic or ergonomic issue that a particular device was designed to correct or improve, it’s almost guaranteed that the tweak will be useless at best and at worst can even degrade your system’s overall fidelity. Tweaks were created as solutions to problems. Without the problem, you don’t need the solution.

So what would I consider a problem in search of a good tweak solution? Having recently reviewed an entry-level audiophile turntable, I’ll start with one of those. I have one very basic test I conduct with any turntable that I use or review – does it pass the thump test? The thump test is so simple that even a dedicated measurements fanatic can do it.

Here’s the test – place a record, any record on your turntable, place your stylus on the record as you would normally, but do not turn on the turntable motor, so the record will remain stationary (with some turntables when you move the tonearm they will start the motor automatically; for those disconnect the AC cord to the turntable). Now adjust your system for a somewhat lower than normal volume setting with the turntable as your source. Now gently tap the upper surface of the turntable – you will hear a thump through your system’s speakers. Now tap the surface the turntable is sitting on. If the turntable is properly isolated this second thump should be much lower in volume than the first. If it is at equal volume level (or it could even be louder) you need to add some isolation between your turntable and the surface it’s resting on.

I’ve done this test many times. It’s surprising how this simple test can reveal that some popular methods for isolating a basic audiophile turntable are worthless, such as the IKEA bamboo cutting board placed beneath the turntable. Sure, it looks cool, but it does absolutely nothing to isolate the turntable above it.

And what tweaks do work to isolate a turntable? Sand bases, such as what used to be available from Brightstar Audio have proven to be very effective isolation devices, and it’s very easy to make your own sand-filled bases if you have a modicum of carpentry skills. I’ve also used air isolation bases, Which Brightstar also used to make, which used a small partially inflated kids tricycle tire as its air bladder. They too have proved to be effective for isolation. Again it’s quite easy to DIY an air isolation base.

AC power line noise is another popular tweak target. And next week I’ll cover how I tested my AC lines to see if I needed an AC filtration in my home. See you then.