Hmm… Who wouldn’t want to engage Beyonce in a threesome? 
Though I’m a single full range driver fan, I’m okay with the other camp of using active crossover and multi way speaker drivers. Different path, same goal.
With single driver, we have simplicity.
With multi drivers, we seek control.
Most likely you’ll be using tweeters, mids and woofers from different manufacturers with different specifications, particularly sensitivity. And the key to integrating all these drivers singing is a crossover system.
Active crossovers like the Behringer DCX2496 does this particularly well. With a touch of a few buttons, you could choose your crossover type, slope and equalize the gain of your filters to match the drivers you are using. Great stuff indeed!
But what if you are a fussy pot who prefers everything done in the analog domain?
Or perhaps you need larger gain than available from your active crossover?
Enter Beyonce!
Though Beyonce is designed as a stereo preamp, Beyonce2 controls volume of 3 stereo sets, albeit all with same gain. So some engineering hard work is required to modify her to have 3 stereo sets of independent gain.
Here’s an implementation.
Some hardware modification and A LOT of engineering on the software later, we have a fully functional 6 channel (3 stereo sets) preamp with digital gain control and 3 sets of gain.
For simplicity, the 3 sets are named A, B and C. Of course, if you desire more than this, let me know!
Integrating the offset control into the Apple remote control is quite a task. To access the Offset Menu, press >>|.
Here’s the controls within the Offset Menu. As you can see here, gain and attenuation for each stereo set could be configured for -12dB to +12dB. As we only have 2 characters to display this info, 10, 11 and 12 are displayed as A, B and C.
Upon power up, we start off with Mute which is -96dB. If you press “+” to increase volume, master volume starts at -36dB.
So if
A is set to n3, B set to P5 and C set to nA,
this means
A is programmed for -39dB, B is -31dB and C is set to -46dB.
Every incremental step corresponds to 1dB in gain/attenuation. If you desire greater control than this, let me know. The chip could be configured for 0.5dB increment. There’ll be more programming of course.
Note that you could also save your settings by accessing menu SS (for Save). Settings will be saved via the onboard EEPROM of the micro-controller. 88 will be displayed and blink twice during writing.
Upon power up, you have this new setting! Until the next time you rewrite it, of course.
So now, do you fancy Beyonce? How about 3 of her loveliness?
