Production of Bridge-T Attenuator (Extra Edition)

My preamplifier has two output circuit for low and high frequency.
I needed to adjust signal level between high and low freq.
Then I insert another Bridge-T attenuator (600 ohm Max 15dB attenuation) to high frequency circuit.
This page, I wrire design and production of extra level adjusting attenuator.

Please check the circuit above, use rotary switch to choose R1 & R2 combination to control attenuation.
For this extra attenuator, I chose Seiden Rotary switch as same as main volume.
But chose 16 steps type called 56SG(56008)
Switch has 16 steps and each step has 1dB difference of attenuation.
I show R1 and R2 combination below.

This is the photo that extra attenuator is installed to Preamplifier.

Maybe difficult to see this extra attenuator, left side is the one.
Main purpose is gain adjustment between high and low frequency, but I can use this attenuator for equalizing when I play old LPs recorded before RIAA. Of course I know it is not proper way, but it’s very convenient for me.