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Solution , possible, workable

To get an odd value R, its not ever OK in audio to series-connect Rs, sounds very bad. However, you can parallel Rs, ONLY if you use like-value Rs. The closer the matching of the Rs, to each other, the better it will sound.

Lets look at your 422 Ohms requirement. No mention is made of Watts needed, lets assume 1 Watt or less.

OK, get out your hand held calculator, and compute the value of 422 at various multiples. Lets see..... 3 is 1266 Ohms, four is 1688 Ohms, five is 2110 Ohms and six is 2532 Ohms.

Go to the Michael Percy catalog, and look up Roederstein Resista MK-3 1/2 Watt resistor values, that come CLOSE to the computed multiples values.

Lets see:.................... Standard R value ...............Computes to :

( 3 Xs 422 ) 1266 Ohms .... 1.27 K...................... computed 423.33 Ohms

( 4 Xs 422 ) 1688 Ohms .... 1.69 K.......................computed 422.50 Ohms

( 5 Xs 422 ) 2110 Ohms .... 2.10 K ( out of stock ) ....computed 422.00 Ohms

( 6 Xs 422 ) 2532 Ohms .... 2.55 K ..................... computed 425.00 Ohms

These MK-3s sound good, and are inexpensive, I'd order a number of 1.69 Ks, and match them with a good DMM ( eg : Fluke 8060A 4.5 digit ) as close as I could....in other words, order MORE than three pieces.

There you have how " I " do it, when I need an odd value. Hope this assists some of you.

Jeff Medwin




Edits: 03/20/17

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