# Powered Sub Auto On not working



## fviola (Oct 1, 2012)

I have a powered sub, Polk PSW10 connected to my Onkyo Sr-535 with a standard subwoofer cable, not a y-sub cable. 
I was told to turn the Low Pass all the way to 150 to essentially create an LFE. I then placed my Sub into Auto On.

On my receiver, after doing the auto calibration, the crossover frequency was set to 100 and my sub speaker level was set to 0 dB.

I generally keep the volume from anywhere betweeen 20-50 on my system. I noticed that when watching a movie at 35, the bass sub would never turn on, even if there was bass present.

I went into my receivers setting and I adjusted the sub speaker level to +6dB, which turns the sub on at volume level 35.

I was wondering, is this the normal way for the auto on to function? That the receiver must be sending a specific level of sound to the sub in order for it to turn on?

If so, is there any problem with adjusting the speaker level within the receiver to such a higher value? I was thinking of adjusting the level to something like +10dB and then lowering the gain on the sub itself. This would hopefully turn on the sub at lower volumes.

Any help on this matter would be great,

Thanks


----------



## willis7469 (Jan 31, 2014)

The problem with going into +values is you can introduce clipping into the signal, and therefore distortion. I'm surprised at 0 you're having trouble. MV of 35 might be too low, but I use relative scale so I don't know about that. Instead of + 10, try something like + 3 to start and see what happens.


----------



## fviola (Oct 1, 2012)

willis7469 said:


> The problem with going into +values is you can introduce clipping into the signal, and therefore distortion.


That is what I was afraid of, so I did some further testing on this.

I set the sub back to 0dB and did the tone test from my receiver settings. During this test, the sub would not turn on at any volume other than 45 or higher.

I put on Deadpool from my cable box. I needed the volume during heavy action scenes to be at around 45 in order to get the sub to turn on.(similar results as before)

I then put on the blu-ray of Dredd. At volume 20, the sub turned on. 

So it seems that different sources are doing different things even though a signal is being sent in all three scenarios.

As a sort of a compromise, i set the sub speaker level to +3dB as you suggested to minimize the distortion but to also activate the sub at lower volume levels.

I don't know what else I could do.


----------



## Wayne A. Pflughaupt (Apr 13, 2006)

Those receiver menu dB settings don’t really have any value, meaning they are not the same from one brand to the next. For example, for some the highest setting is 0,while others go to +6 and others even higher. 

I’d say turn the receiver’s sub output up as high as you need to get your sub to kick on when it should. It will work fine. Mine is currently set to max and I'm not having any distortion problems.

Regards, 
Wayne


----------



## fviola (Oct 1, 2012)

Thanks for the input

I think I am going to leave my level at +6dBs. I don't hear distortion (but i am no expert) and i am satisfied with the volume level of my receiver when the sub kicks on.

thanks again


----------

