Gain overlap changes

[Taxed1]

Hey all, I recently noticed that when I use my DD1+ and set up my amp to 8dB overlap then set the crossover to 80Hz & the subsonic to 25Hz, I check the overlap again & its 6.5dB. What the heck! So I remove the crossover & subsonic & retest & I’m back to 8dB. So what are your thoughts? Should we set crossovers first or follow the procedure of the book and Steve’s videos? It seems my crossovers effect my overlap.

 

Another question I have is if I set my amp up using the DD1+ properly. Yes, I know how to use it, but I am noticing that my clip light on the remote knob lights up passed volume 37. So basically I have a Pioneer deck that is clean on the DD1+ up to max volume 40. I set up the amp then switch tracks to set my 8dB overlap. No matter the song I see clipping at 36-38 but shouldn’t I be able to play at volume 40 per the DD1+. Could it be my amp is just finicky? Should I trust the amp clip light or the DD1+? The clip light flashes at that volume, not steady full light on. Maybe I am over analyzing this. Not all songs are -5dB so probably the clipping at 36-38 is normal..?

[Dafaseles]

As far as the crossovers effecting the overlap, I couldn't tell ya. 

But there second question, so basically setting an overlap is essentially introducing an acceptable amount of clipping into the system. Some call it a soft clip. So yeah, seeing the clio light flicker every now and again isn't something to worry about too much. Now if you slap for a while and you start to smell something, or you feel your dust caps and they feel hot or warm, then that's too much clipping

[liteblue]

I am not an amplifier technician but my best guess is this. 

 

Less overlap. Reason for low-pass and high-pass/subsonic is to limit potential energy across a range of frequency. Crossovers are not a flat wall, they roll off. So at -12 db low-pass set to 80 hz means at 80 hz amplitude is reduced by 12 db. This is a parabolic curve that has a vertex someplace. Because of this you are seeing lower overlap at your test frequency as the xover starts to roll off. 

 

Clipping. Crossover also direct power to range of frequency. Music is dynamic and the speaker is trying to play everything that amplifier can throw at it. When we apply subsonic/infrasonic and low-pass we are saying only amplify frequencies in this range. More potential energy (voltage) is translated to fewer frequencies inside the bandpass.

 

Clip light flashing very very briefly is not the end of the world if the voice coil can dissipate the heat (wattage). So at or below rms rating. But I would not suggest it. 

 

I have not tried retuning gains after setting crossovers with a dd1/+. But when I did it with just dmm I was not happy. It lost something musicality, did not sound as "accurate."

 

Thats my two cents. Hope it helps.