The second last column is the spot noise figure you get when you connect an ordinary 47 kohm load to a V15 III cartridge, with no other noise sources at all. When you have a 3 dB noise figure target, you definitely need an electrically "cold" termination. It's worse for less lossy cartridges.
@rayfutrell: My noise criterion is also noise figure. But most RIAA stages do not achieve your criterion.
Hi Drone,
Unfortunately, Artificial Intelligence seems to be rather incorrect.
Contrary to what it suggest, none of these listed Carts seem to have tapered Cantilevers.
1. Boron Tapered Cantilevers
- Lyra Atlas (SL, Lambda) – Uses a tapered boron tube for ultra-low mass and rigidity.
- Ortofon MC Anna Diamond – Features a tapered boron cantilever with diamond-coated stylus for extreme detail.
- Dynavector XV-1t – Tapered boron design for improved tracking and high-frequency response.
2. Sapphire Tapered Cantilevers
- Koetsu Urushi Vermilion/Platinum – Handcrafted with a tapered sapphire cantilever for lush midrange and durability.
- Clearaudio Goldfinger Statement – Uses a hollow tapered sapphire tube for minimal resonance.
3. Diamond-Coated or Solid Diamond Cantilevers
- ZYX Ultimate Airy – Tapered diamond-coated boron for near-zero distortion.
- Phasemation PP-2000 – Solid diamond tapered cantilever (rare and ultra-high-end).
Hans
In RF there's only one frequency to worry about though (I assume narrowband), but here its wideband and the noise has a whole spectrum, and parts of the spectrum are more annoying than others. 30% is nearly 3dB, the human perception of relative level is more like 0.25dB, though absolute level is probably more than twice that.
It more concrete terms reducing high-frequency hiss compared to mid-band "rushing" by as little as 1dB can be noticeably beneficial.
It more concrete terms reducing high-frequency hiss compared to mid-band "rushing" by as little as 1dB can be noticeably beneficial.
At the higher audio frequencies, the noise figure due to the 47 kohm load resistor is about 4 dB using a Shure V15 III (and higher using a less lossy cartridge), see post #101. It's all without any record playing, of course, but apparently record surface noise is mostly low-frequency noise.
I made a silly error, I forgot to take the opposite of the phase of the impedance when calculating the admittance. With that corrected, the electrical response drops off only 8.2 dB rather than 12 dB at 20 kHz compared to 1 kHz. Anyway, you still need a big peak elsewhere to get a reasonably flat overall response.
Magnitude of the transfer from the Thévenin voltage (open-circuit voltage) to the loaded voltage with the recommended 47 kΩ in parallel with 450 pF load, normalized to the value at 1 kHz, vertical scale in dB, horizontal in Hz: