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.

Vifa P13WH upgrade (P13WH-00-08) midbass woofer

Arguably the best midbass in existence. Impressive flat frequency response and cast magnesium frame. Some comments, review, and designs with this 5.25" midbass:



Linkwitz' mid test

Lynn Olson' Ariel

Esquire

North Acoustics Spirit

Marshall Leach

Tempest

Troels Gravesen test

SDS Okara

Daline Transmission Line

The Merrimac

My own S7 OB Speakers

Manufacturer's specification

LDSG review

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