katarakt wrote:Are these 1% resistors exactly as good as the 5% ones? because the 5% are in the official parts list.
The % of the resistor refers to variation given to ohm values.
100ohm resistor with 5% can actually be between 95ohms to 105 ohms. Generally, this doesn't make huge difference, however in notes and tones they do.
The R1R2 ladder has been made with matched pairs with 1% metal film resistors, that should be exact. There you should not use 5% things or you have hard time
to measure correct pairs.
The original TB-303 used 0.1% precission resistors with selected pairs to get the exact values to the R they wanted. This means to have exact notes.
To get this problem sorted way easyer is to use precission Trimmers. But Well, thats too raw school to be done xD.
Metal film resistors are typically 1% meaning their measure variates in 1000ohms... it is 1990 to 1010 ohms.
(1/R1) + (1/R2) = 1/Z [Z is total R] You most likely want to get the Z exactly to the R value needed.