Cheap DACT attenuator (6 steps)

Using 6-Pole, 2-Position, 1-gang rotary switch from dicksmith. Any brand will do and the more the pole, the better. The 2 position provide left and right channels.

Design the attenuation by using the online calculator something like this, using dB attenuation steps of 56-39-26-12-0:


So the theoretical R values from gnd to signal in ohms are:
gnd-79-482-1,945-10,053-3,7441-signal

But for nearest real value use:
gnd-75-470-1,800-10,000-(36,000+1,800)-signal

This is better than my blue-aps pots. Total cost $4.

Dipole bass

To obtain the purest sound I got rid of the ported sub and use 10" woofer with fully equalised response to compensate OB frequency attenuation.

First attempt to use H-Frame was successful but I did not like it aesthetically. So I went back to plain OB.

H-Frame experiment. I did not like the looks and discarded this.

The final setup is tri-amped system with plain open baffle. Mid & high are actively crossed at 3.5kHz using 24db/oct linkwitz-riley filter. The woofer is crossed at 120Hz and equalised towards low frequency at 6db/octave.


http://www.youtube.com/watch?v=aNmZRxdRQr0