47 Position Stepped Attenuator Resistor Lists:
Goldpoint 47-Position resistor lists yield 1.5dB of attenuation for every step.
This gives a total of 67.5dB of attenuation for our most common 47-Position units.
|To make your own 47-position stepped
attenuators, use Goldpoint 47-position blank switches which were designed for this purpose: Goldpoint P/N V47C-1 (mono), V47C-2 (stereo) or V47C-3 (quad). Pictured below is a stereo 47-position blank switch which has the through-hole resistors installed.|
There are two additional (unusual/special) columns in the chart below for the 10K
stepped attenuator value: 1dB per step and 0.5dB per step.)
- For the 1dB resistor list, you get 45dB attenuation (total).
- For the 0.5dB resisitor list, you get only 22.5dB attenuation (total).
Switch position #1 (full counter-clockwise rotation) is OFF (of course) = infinite attenuation.
How to Make Linear Taper Stepped Attenuators:
To make a series type linear taper stepped attenuator, divide your
chosen stepped attenuator value by the total number of switch positions
minus one (in our case 24 - 1 = 23 or 47 - 1 =46). This resistor value is then
used for every resistor on your stepped attenuator.
| Example: To make a
10K 24-position linear stepped attenuator using one of the V24C Custom switches,
divide 10,000 by 23, which is 434.78 ohms. Using off-the-shelf common resistor
values, use twenty-three 432 ohm resistors per channel (which makes a 9.936K
stepped attenuator.) Or use 442 ohms, which makes a 10.17K stepped attenuator.
(Fourty-six resistors are needed for a stereo unit.)|
| Example: To make a
10K 47-position linear stepped attenuator using one of the V47C Custom switches,
divide 10,000 by 46, which is 217.39 ohms. Using off-the-shelf common resistor
values, use fourty-six 215 ohm resistors per channel (which makes a 9.89
stepped attenuator.) Or use 221 ohms, which makes a 10.17K stepped attenuator.
(Ninety-two resistors are needed for a stereo unit.)|
|KOA Speer brand,
MF1/4 and CF1/4 Series The MF1/4 series are truly excellent sounding 1% Nickel Chromium (NiChrome) semi-precision through-hole resistors. They are our most highly recommended brand of thru-hole resistor.
Although very afforable, we recommend them because of their clear sound
quality, which is likely impossible to beat at any price. For resistor values of 10 ohms or higher, use the KOA MF series (1% metal film). For values below 10 ohms, use the KOA CF series (5% carbon film) (see
bottom of this page for both MF and CF Series)
- The resistor values are color banded -
(see our Resistor
Color Code Chart). All resistor values are avilable from garrettelec.com. Some stocked at
|IRC RC55 Series The IRC RC55 series are 0.1% tolerance,1/4W through-hole thin film NiChrome metal film
resistors. Their sound rivals the sound qualities of the very best SMT (surface mounted) resistors, (as are used on standard
Goldpoint stepped attenuators). In my opinion, the RC55s are better sounding than expensive, high-precision Vishay bulk foil or even Caddock non-inductive resistors. Install IRC 55 series resistors on DIY Pro Audio balanced line stepped attenuators or any DIY application where you need/want a high precision stepped
attenuator. They are black color with white resistor value numbers.
keywords: IRC resistors)
bottom of this page - available from www.mouser.com.)
(1/4 watt) and RN60 or CMF60 (1/2 watt) These are 1% tolerance, Ruthenium type metal film resistors. Mediocre sound quality even though they are used by many audiophiles.
The "55" is 1/4W size, whereas the "60" is 1/2W watt size. They are brown color with black resistor value numbers. (Mouser keywords:
Vishay/Dale RN55D, RN60D, CMF55, CMF60)
(available from www.mouser.com.)
brand 1%, 1/4W and 1/2W resistors: These are cheaply made 1%
tolerance Ruthenium type metal film resistors. They may be the
least expensive thru-hole resistors you will find. Their sound quality is mediocre but considered OK or "acceptable". They are light blue/green color with color banded resistor values.
(see our Resistor
Color Code Chart) They are readily available and well stocked at Mouser.com. (keywords: 273-1K-RC) (available from www.mouser.com.)