For some strange reason, I have been thinking about the strain gauge phono cartridge. And, here’s the weird thing. I have never heard one.
What’s interesting to me about this strange beast is how different it is from your conventional phono cartridge.
I am always fascinated by truly different.
Most phono cartridges are generators. They rely upon movement to induce a variable magnetic field which in turn generates a voltage. The movement occurs in response to the needle in the record groove. Attached to the needle/cantilever arrangement is either a small coil of wire (moving coil) or a small magnet (moving magnet). As the disc spins the needle moves and we generate a tiny electrical signal which we first amplify and then pass it through an EQ network called the RIAA curve.
A strain gauge does not generate a voltage. Instead, it disrupts either a small voltage or impedance which is then converted to what we need to play music.
Interestingly enough, strain gauges don’t work into phono preamplifiers. Instead, they require a special analog input that is more closely related to a standard analog aux in. This is because strain gauge cartridges don’t need the EQ correction normally applied through the RIAA curve.
I see that Soundsmith is offering their version of a strain gauge cartridge and input box for $10K.
Why are we going down this road in today’s post?