The audio resistors LEFSON RESISTOR and LEFSON RESISTOR-D (dual) are very high performance pure silver / carbon audio resistors. They are made of a pure graphite resistive element and pure silver leads. Suitable for speaker crossover
or Emitter/Source resistor of transistors in preamplifier/amplifier, the LEFSON RESISTOR and LEFSON RESISTOR-D are pushing up the limits of sound reproduction.
The different lines PREMIUM, SUPRA and ULTRA allow the user to choose the level of required performance. Near zero inductance and distortion, heat sinkable, mechanical earthing possibility,
incredible neutrality, the LEFSON RESISTOR and LEFSON RESISTOR-D are the ultimate solution to improve any analog circuitry.
As all other LEFSON products, hand assembly and electric tests are made in our workshop in Northern France.
Our audio resistors are already used by many professionals and passionated audiophile people.
Please see the Users page to read users reviews around the world !
The RESISTOR-D (dual) resistors allow to improve a passive attenuator (H-PAD, L-PAD, T-PAD...), output resistors of transistors stages (emitter, source) or simply any assembly of two resistors with a common point. There are many advantages :
- Internal link of the common point
- Reduced size
- Thermal stability
- Retail price lower than two single resistors
To achieve optimum results, they need to be burned-in with audio signals for at least 80 hours.
The LEFSON resistors are divided into six models, as shown in the table below. All ohmic values are available, according to the following ranges :
| MODEL | RESISTANCE | Pmax * | RESISTIVE ELEMENT |
LEADS | END CAPS | PRICE |
|---|---|---|---|---|---|---|
| DC current | Carbon | 99,9% Silver | 99,9% Silver | |||
| --- Single RESISTOR --- | ||||||
| PREMIUM | 0R47 -> 1R5 | 4/6W | SINGLE | Ø0.8mm | STANDARD | 50€ |
| PREMIUM | 1R5 -> 220R | 6/10W | SINGLE | Ø0.8mm | STANDARD | 50€ |
| - | - | - | - | - | - | - |
| SUPRA | 0R47 -> 1R5 | 4/6W | SINGLE | 2 x Ø0.8mm | ENHANCED | 70€ |
| SUPRA | 1R5 -> 220R | 6/10W | SINGLE | 2 x Ø0.8mm | ENHANCED | 70€ |
| - | - | - | - | - | - | - |
| ULTRA | 0R33 -> 1R | 6/10W | DOUBLE | 2 x Ø0.8mm |
ENHANCED | 130€ |
| ULTRA | 1R -> 100R | 8/15W | DOUBLE | 2 x Ø0.8mm |
ENHANCED | 130€ |
| --- Dual RESISTOR --- | ||||||
| D-PREMIUM | 0R47 -> 1R5 | 4/6W | SINGLE | Ø0.8mm | STANDARD | 75€ |
| D-PREMIUM | 1R5 -> 220R | 6/10W | SINGLE | Ø0.8mm | STANDARD | 75€ |
| - | - | - | - | - | - | - |
| D-SUPRA | 0R47 -> 1R5 | 4/6W | SINGLE | 2 x Ø0.8mm | ENHANCED | 100€ |
| D-SUPRA | 1R5 -> 220R | 6/10W | SINGLE | 2 x Ø0.8mm | ENHANCED | 100€ |
| - | - | - | - | - | - | - |
| D-ULTRA | 0R33 -> 1R | 6/10W | DOUBLE | 2 x Ø0.8mm |
ENHANCED | 225€ |
| D-ULTRA | 1R -> 100R | 8/15W | DOUBLE | 2 x Ø0.8mm |
ENHANCED | 225€ |
Recommended retail price
* Pmax :
The power rating is expressed with two values (example 6/10W). The first one is the maximum allowed power without any heatsink. The second one concerns the maximum
allowed power when the LEFSON RESISTOR is fixed on a heatsink or to a reliable case. Regarding this purpose, using thermal paste is recommended.
All these power values are measured with direct current. When AC operating (audio), the maximum short term power allowed is significantly higher. During our post-manufacturing tests period, the LEFSON RESISTOR is stressed with
current peaks, up to 20W.
