There continues to be a long standing myth that all resistors sound the same. Resistance is easy to create, recreate, define, test and measure, therefore it should not be a source of significant audible distortion.

This is absolutely untrue.

Subjective evaluation published by Duncan and Colloms (1) outlined the enormous differences is resistor sound quality, not only between different types of resistors but also between different lines of the same type.

The most important characteristic of a resistor is its dynamic stability; that is, its variation in resistivity and other qualities under dynamic conditions. Sand cast resistors, like those commonly used in crossover networks, are dynamically unstable due to their high temperature coefficient (Tc), typically about 400 ppm/°C. This means that their resistance increases significantly when they operate at higher temperatures. Because the actual resistive element heats up instantaneously as current passes through it, it has a higher resistance to loud sounds than to quiet sounds - so it lets proportionally less of the loud sounds through. This is called dynamic compression, and is similar to the compression used to increase the broadcast radius of AM radio.

Both OHMITE and NORTH power resistors are wirewound of a thermally stable wire alloy in a non-inductive winding pattern over a ceramic core, and are silicone-ceramic conformal coated. Their design has been optimized to provide a purely resistive load under highly dynamic conditions over an extremely large bandwidth, and they exhibit a temperature coefficient of less than 50 ppm/°C.

All of our OHMITE and NORTH power resistors are also 1% tolerance, and surpass all rigid military R-26 specification, including a requirement that they withstand repeated, 1000%, five second overloads without any damage whatsoever. Lastly, our resistors feature all welded construction and are pre-stabilized, and will provide decades of flawless service even in environments of significant stress.

The Sound

Our OHMITE and NORTH resistors are completely transparent. The gritty texture of virtually all sand cast resistors is eliminated via the wirewounds. The hardness usually associated with metal dome tweeter is simply not there. Our resistors have absolutely no sonic signature whatsoever. Furthermore, they bring to most systems a kind of fine resolution that is only rately associated with dynamic driver technology. These are a performance leap over the usual 50¢ sand cast resistor.

1% Matched Pairs

Our OHMITE and NORTH resistors are provided in ±1% matched pairs, for a maximum SPL variation of ±0.1dB.

• 10 Watt Wirewound
• 1% Tolerance
• Overload: 10 Times rated wattage for 5 seconds

• Temperature Coefficient:
  1.00 Ohm to 8.06 Ohm
  < ± 50 ppm/°C
  10.00 Ohm to 221.0 Ohm
  < ± 20 ppm/°C
• Dielectric Withstanding Voltage: 1000 VAC

5 - 9 pieces: 10%
10 - 24 pieces: 15%
25 up: 20%

Please contact our office for larger quantities.

OEM and Distributor Accounts, please contact our office for pricing and custom resistance value minimums. North Creek Music Systems is the exclusive distributor of NORTH power resistors.

Resistor FAQS

What is the difference between NORTH and OHMITE power resistors?
None. North Creek Music Systems developed the NORTH power resistor family specifically to be identical to the OHMITE power resistors. The process took over 14 months, involving evaluation of samples from over 20 manufacturers in the USA, Canada, Europe, and Japan, and ended when we discovered a small US firm which could custom manufacture a product precisely to our design goals. The NORTH power resistors were developed in response to changes in Ohmite's manufacturing and distribution policies, which created unreasonably long lead times (although the quality of the product remained excellent). We still have Ohmite resistors in the distribution pipeline, and will continue to carry them as long as the stock lasts. All new values and restocks will be NORTH power resistors.

Are Metal Film resistors superior to Wirewound Resistors?
No. In virtually every comparison we have made, and well as those published by Duncan and Colloms (1), wirewound resistors clearly outperform even the best metal film resistors. This should come as no surprise. Wirewound resistors use actual high quality metal alloy wire as a resistance element, rather than a thin, poorly-conducting vapor-deposited metal film. On the quantum level, the resistive wire of a wirewound resistor has tight molecular packing and long alloy crystals, where as the vapor deposited metal layer of a metal film resistor has large gaps between molecules and small crystals. The integrity of the signal degrades very little in an alloy wire, but significantly in the vapor deposited metal film. The only benefits of metal film resistors are size and cost, neither of which are of any significance in this context.

How critical is pair matching?
Most resistors are ±10% tolerance; that is, a randomly selected pair can vary by as much as 20% and still be considered in spec. In series with a tweeter, that 20% variation translated directly into a 2dB output difference between the left and right channel - even if the tweeters are perfectly matched! This level of difference creates density variations within the sound stage, tends to skew specific images to one side or the other, and broadens image outlines. Tighter tolerances solves these problems. Always insist on ±1% matched pairs.

How can one achieve values between the stock values?
Use a combination of larger resistors in parallel. The equation is:
Req = (R1 * R2)/(R1 + R2)
where Req is the equivalent resistance of the two parallel resistors and R1 and R2 are the stock resistors.

What about resistors in series?
We do not recommend series combinations as a rule. However, the OHMITE power resistors are very clean and we have used them in series with each other successfully in the past. The equation is:
Req = R1 + R2
where Req is the equivalent resistance of the two series resistors and R1 and R2 are the stock resistors.