4435 L Pad Questoin

[allen mueller]

I would like to replace the L pad (R202) with resistors to fix the response in the flat position. I found the value for R201 for a flat response but have had no luck for the L pad.

I could take mine out and measure but one was already bad, so i am leery that any measurements i make of the other might be inaccurate.

I have been searching with no luck and i apologize if this has been covered before.

Thanks

Allen

[Ruediger]

I would like to replace the L pad (R202) with resistors to fix the response in the flat position. I found the value for R201 for a flat response but have had no luck for the L pad.

I could take mine out and measure but one was already bad, so i am leery that any measurements i make of the other might be inaccurate.

I have been searching with no luck and i apologize if this has been covered before.

Thanks

Allen

I will give You the "formula" how to calculate the values.

The 8 Ohm L-pad turns an 8 Ohm load (Rload) into something which again has an impedance of 8 Ohms. It does this by conncting a resistor (Rpar) parallel to the load, and by connecting a resistor (Rser) in series to the load.

Let A be the gain, 0 <= A < 1. Let A be not equal to 1.

Rser(A) = 8 * (1 - A)
Rpar(A) = 8 * A / (1 - A)

If A is 1 (full gain, or "flat"), then Rser = 0 (piece of wire) and Rpar = infinity (not there).

Ruediger

[allen mueller]

Thanks for the info. I eventually found what i was looking for in this thread.

http://audioheritage.org/vbulletin/showthread.php?t=5209&highlight=r202


AL