@rrm
1. add up the coil ohms plus loading ohms, e.g. 30 + 100 = 130
2. divide the loading ohms by the number from step 1, e.g. 100 / 130 = 0.769
3. take the log (base 10) of the result from 2. and multiply that result by 20; that number represents the loss in dB versus a theoretical load of infinite resistance (i.e. NO load on the cartridge), e.g. 20 * log10(0.769) = -2.2788 dB
Calculate loss for other loading values and subtract them to determine relative losses.
1. add up the coil ohms plus loading ohms, e.g. 30 + 100 = 130
2. divide the loading ohms by the number from step 1, e.g. 100 / 130 = 0.769
3. take the log (base 10) of the result from 2. and multiply that result by 20; that number represents the loss in dB versus a theoretical load of infinite resistance (i.e. NO load on the cartridge), e.g. 20 * log10(0.769) = -2.2788 dB
Calculate loss for other loading values and subtract them to determine relative losses.