Audio Benchmark "PAF" (Power Amplifier Factor):

The designers of Transparent Sound would like to compare audio power amplifiers with each other within a certain kind of price range. The only reference we found in the market, were the criterions of some high end magazines and most of these were not independent enough as they were often related with advertisers in the same magazine.

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Stereo Test

We came to the conclusion that there is no measurement reference in the market to compare these amplifiers. So we came up with a new standard which can handle most of the audio power amplifiers on the market.

Transparent Sound decided to make three price categories: one of 0 to 2500 Euro, one of 2500 to 4500 Euro and one of 4500 Euro and above.

In the benchmark we came up with a relation for the size and the weight of the amplifier, the average of the maximum power in 8, 4 and 2 Ohms and the price in Euros, everything compensated with a factor 10000 to make the benchmark readable.

The PAF (Power Amplifier Factor), as we call this relation, is mean as a benchmark for high end audio equipment. This is a subjective factor and tells us nothing about the sound quality of the amplifier. The benchmark is a relation of some physical factors combined with electronic measured values.

Calculating the PAF

The PAF can be calculated by the following formula:

l = length (m)
b = width (m)
h = height (m)
m = weight (kg)
P = maximum weight power at THD < 0.1% (Watts)
(P = average of power in 8, 4 and 2 Ohms)
B = Price (Euro)

The formula is based on a mono amplifier. For stereo amplifiers, you have to divide the answer by two to get the PAF. We've calculated the PAF's of some commercial available power amplifiers and put the results in a table for you. See download file here below