Strain Gauge Engineer Peter Ledermann Comments on the SG System "The Strain Gauge cartridge is not at all like any other cartridge. All other cartridges, whether moving magnet, moving coil, or moving iron, are "generators" - that is, you put motion in, and you get energy out.....a tiny voltage that you amplify and send to your speakers. The key here in describing all other cartridges is in the word MOVING. All other cartridges need to move a mass around - a magnet, and iron core with wires (moving "coil") or moving iron. They are all magnetic generating systems, which require a mass to be constantly moved to generate a voltage.
When you move any mass, it has stored energy, just like your car when you get it going. When you need to turn, or slow down, the mass tries to keep you from doing so. Imagine a stylus in the groove of a record that must make lots of changes in direction to follow the groove walls. Imagine how the mass of the generating parts must restrain the stylus as it tries to move.
Now, imagine driving a car where you and the car have NO MASS. If you can, then you can understand only one reason why the Strain Gauge is so exciting; it has almost no "stored energy" in the moving system - there IS no large amount of "mass" to move around - it does NOT have to move around a magnet, or wire coils, or iron. This means that the stylus stays in much better statistical contact with the groove walls of your records because there is no large mass trying to keep it from doing so. Imagine how different that sounds.
Inertia (the law by which mass tends to stay at rest or continue in the direction in which it was moving) makes all styli "jitter" or jump about in the groove of the record, and not stay in intimate contact with the groove wall. If a stylus can't follow the groove wall, you cant hear what's on the record. Its that simple.
So how does it work if it doesn't generate a voltage???
The SG cartridge has two Strain Gauge elements, pieces of silicon crystal that when compressed or expanded by tiny amounts, change resistance. The cantilever suspension, a necessary part of any cartridge, is coupled to these elements. The energy that is usually always "lost" into the suspension of all cartridges is used to create the signal in our Strain Gauge cartridge. It is also a purely "resistive" system, with no coils of wire to alter the high frequency performance, or pick up hum, noise or radio stations! Our preamp supplies it a flow of electricity, which it varies, and that gets amplified.
Because it has ultra-low moving mass, and because it uses no wire coils, it has a high frequency performance to beyond 50 Khz. Because it goes all the way down to DC, we can use that DC information to display tracking forces, forces on each groove wall, record eccentricity and "AC" component of the tracking force (record warp). Because it does NOT have to move around a large mass, and has little stored energy, it can track at one gram without "jittering" or chattering down the groove walls, and therefore stays in intimate contact with the record groove. And because we engineered it carefully, our Strain Gauge has user replaceable styli, a first for high end cartridges.
That's a lot of "because's". And there's more.
I will be glad to consult with those who are seriously interested in owning this system. All cartridges are individually hand-made by me, and I take great care in doing so.
Thanks for your interest." -Peter Ledermann/President & Chief Engineer
SG-210 - Strain Gauge Cartridge & Preamp System - Fixed output and +10dB variable output with front panel volume control
SG-200 - Strain Gauge Cartridge & Preamp System – FIXED line output only
Testimonials “Now, with one giant leap, your strain gauge cartridge has leapfrogged the finest moving coil cartridges..... I was completely stunned....” -Ijaz Khan, MD
"The area in which the strain gauge system really excelled was in its ability to project a three dimensional image. It was surreal. The openness and air around the musicians was like nothing I have ever heard." -Stephen Kaufman, MD, PHD
No "RIAA" filter circuitry is required or used in our preamp - just one ULTRA clean gain stage (this is because the Stgrain Gauge is a "displacement" device, not a "velocity" sensitive device like magnetic cartridges).
System Price includes Strain Gauge Cartridge and Soundsmith SG Preamp of your choice
"Fixed" Line level & +10dB variable outputs, both Balanced and Unbalanced (via RCA jacks)
High Compliance design and feedom from low frequency saturation assures excellent tracking ability and performance with any tone arm
All preamp models now feature toggling between the Strain Gauge function and single or (multiple) line inputs for maximum hookup flexibility to your equipment
Low tracking forces with extreme precision
Compatible with any 1/2" mount headshell - uses STANDARD 4 wire tone arm wiring
Frequency response DC-70kHz with only 10° of phase shift in the audio band (rumble filter built in @ 12 Hz - passive type before single flat gain stage
Front panel displays for tracking force (digital readout), AC component of the vertical tracking force, force balance per groove wall, and record eccentricity! (on models 810, 610,and 600 only)
Fixed and variable, balanced and unbalanced outputs via RCA jacks. Our variable output will provide up to +10dB level, and may be used DIRECTLY into any amplifer with balanced or unbalanced inputs.
Advanced muting features: Automatic Cue -Up muting (works with any turntable, and is user defeatable), manual muting control, and fault-sensing auto-mute to allow "hot plugging" of the tone arm or cartridge with the volume up, thus eliminating buzz or transients (allows stylus cleaning, adjustments, etc....)
User replaceable styli available in varied compliance and configurations (Ruby & Aluminum cantilever, Nude Contact Line &, Elliptical Styli - 78 Styli) Styli replacement Costs from $149.95 - $499.95
IR Hand Held Remote for remote controlled models controls volume, mute, power (and input switching on the SG-510 and SG-810)
All models feature front panel finger "light-touch" control switches for power, manual muting and front panel lighting control (on models 810,610 &600) allowing adjustable front panel lights from "automatic room lighting level" to variable intensity - full bright to off. (All other models have rear manual control for lighting intensity) Our lucite volume knob changes color to indicate the state of operation: RED (standby); Yellow (auto-mute); flashing yellow (manual mute); Blue (unmuted - playing)
Our Strain Gauge cartridge requires specialized preamp circuitry, and is sold with any of seven models of Soundsmith's preamplifiers - All models have both fixed and +10 dB varialbe outputs - and can be used directly into an "aux" input on your preamp, or used DIRECTLY into any power amplifier.