Quoted from davegauth:The EQ works... The L+R signal coming out of the CN5 is the backbox 10 band EQ. The cabinet EQ will do nothing as ut wpuld be the mixed mono signal for the cabinet.
Keep in mind tapping into the CN5 is like tapping the signal before it goes into the stern amps.. 1 amp chip is L+R backbox and the othe amp is a bridged amp receiving a mono signal and sending 1 channel to the cabinet.
As far as setting the dials and EQ. This is what I like to do:
Set the amp main volume at about 60-75%(3oclock or less on the dial) - Line noise amplification gets to be a little too high beyond that plus many of the mini amps start to distort, clip, and send real dirty power to the speakers beyond this.
Now play some bluetooth music over your phone - crabk your phone volume. Drop your sub volume all the way down so your are just hearing the backbox speakers. Now turn up the base backbox and treble until they sound good. Play alot of different music, base heavy stuff, rocking stuff etc. Once you are happy with that bring up the sub volume with the sub frequency set in the middle. You are listening to when the sub starts to sound just right with the back box speakers. The sub shouldnt stand out by itself - you'll hear that point where it starts to take off bybitself and its gone too far. Back it back down until you hear it, but it doesn't stand out as a seperate component. Now bring the sub frequency up a little, yiu will hear a point where the sub just spunds terrible as you are asking it to produce higher frequencies that it just isnt going to do cleanly. It's also starting to overlap with the backbox speakers, and you dont want much of overlap, thia will create phase issues and sound bad. Again find the sweet spot where it blends and doesn't stand out. Then revist the sub volume and set it again. Make any final tweaks - and yiu are good to go for Bluetooth.
Now - set it for the pin. Leave the mini amp alone for this and set for bluetooth optimization you jsut did from above.
Go into yout utilities and 10 band EQ for the back box. Some random track will play everytime you go into the audio settings. Turn your volume up to about 35-37 on the pin. This will be your max volume now, I use 37. You can go beyond this later when playing, but the signal generally starts to get dirty coming from the CN5. Start at the left slider and move it up and down until the sound is pleasent. Then move to the next and repeat. Just llike before you are goign to increase the slider until it sounds artificial and stands out by itself then back off a until it sounds smooth to you.. Not muted, but smooth, it should be there but not stand out. Do this for each slider... Done..
Note: The far left slider is generally going to be at or below center. These are hard frequencies for the sub to make because It's not exactly in an optimal enclosure, so clipping some of it off helps. You may want to crank this slider as it is going to be tough to hear anythimg until its cranked, but you are better off squashing it to keep things clean down here.
Now go into the DJ mixer and flip through the tracks - then go back into the mixer and tweak a bit. Play a few games and go tweak a little more(Sound effects may need to be compensated for as they can be screechy)
*If you smell that burning coil smell after prolonged listening at loud volumes, then the amp is sending a dirty signal to the sub. This is a sign to turn the amp down a little or turn the sub volume down a little. The Fosi and Fosi pro will send dirty power after around 80% volume. (This isn't because there is too much power for the sub - its the amp reaching its limits to send clean power)
Alright - it's late, I'm really tired and typing this on my phone, I can only imagine how many typos are in this. Too tired to fix now, going to bed.
Thanks Dave I followed your instructions. Helped setting the amp up for sure.
Observations:
1. I don’t think the pro has the same aggressive hi pass filter that the non pro does. Plenty of bass.
2. It’s a challenge bridging the gap between small monitor speakers and a sub. The woofer speaker in the cab did a lot of the heavy lifting for the backbox speakers. Now that is replaced by a sub the backbox speakers need to do most of the work. Don’t get me wrong the JBLs are good, but drive too much bass or volume and they become flabby and buzz - this may be partly due to speaker lights sitting in front vibrating to lower frequencies, I can put some felt between the 2 to try and isolate a bit. I know pinballs and adding speaker lights are not ideal acoustics but hey I need the bling! Especially Foo where my speakers are now synced to the expression lights (thanks ninja camp, awesome job!)
3. After setting for Bluetooth, most of my dials were about 1 o’clock. Anything more than that I overloaded my backbox speakers
4. The setting of 2 different pins was different. 1 seemed more aggressive bass than the other. So variation in same amps and speakers. Guess this may be obvious. For this reason your dial in method is a necessity. We just can’t copy what Dave does.
5. I tried setting the EQ for the back box. And ended switching back to no preprocessing. When playing around with the EQ and going for a bowl type shape (with the ends turned down) suddenly I couldn’t hear Bruce (not a bad thing haha), I fiddled with it again but just found it easier to turn it off and adjust solely on the Fosi. Bluetooth definitely sounds punchier than pin output so a bit of tweaking just for the pin is required.
6. Lastly I had to turn down the subs just a little.
When playing the sub sounded fine, when spectating off to the side suddenly the sun sounded intrusive because the backbox speakers weren’t filling in the sound.
Overall really happy. There was a point where I debated whether a good woofer would have been a better fit than a cabinet sub, but after turning off the EQ and tweaking again, all good
Again thank you Dave, having this sort of upgrade for less than $200 usd is fantastic!
Sydney
