Fixed Attenuator

[JammyDodger]

Hey All,

I am thinking about building a fixed attenuator into my 2x12 cabinet. I thought I would do one jack in the back at 0 dB and the other at 10-12 dB. Does anyone know the resistor values that I should use. Or - can you direct me to how to calculate what I will need?

Cheers, Mike

[Aurora]

What kind of power level are you talking about..????

[Aurora]

Link here:
http://www.m0ukd.com/Calculators/Attenuator_Calculator/

Pi or T - never mind, - also that this is deisigned for RF - just put in the correct impedance values. Input / output is prob'ly the sam ein you case.
Take care that the first resistor will see almost the full power level.

[PCollen]

Hey All,

I am thinking about building a fixed attenuator into my 2x12 cabinet. I thought I would do one jack in the back at 0 dB and the other at 10-12 dB. Does anyone know the resistor values that I should use. Or - can you direct me to how to calculate what I will need?

Cheers, Mike

I think keeping the attenuation variable and external would be more practical, versatile, and adaptable to different playing environments.

[tonewood]

This works:

http://www.diyaudioandvideo.com/Calculator/LPad/

I tried it today with a few different dB cuts. More than -9dB started sounding a bit funky for my single 12Ax7-6V6. Also, I used 2x the wattage that was calculated & the R1 resistor still got plenty warm.

For my 8 Ohm spkr to get a 6dB attenuation, I used R1=4 Ohms/10 watts, R2=8 Ohms at 5 watts. It sounded pretty good but not exactly like the too loud unattenuated version.