Sound intermittently cuts out, overload protection?

[lebowski]

So here's the current setup

HU: Pioneer DEH2200UB

amp: Kenwood KAC8405 60x4

front: Polk db651s

rear: old unknown JL 12" sub

I have some 6x9s on the way that I'm gonna hook up to the amp but currently the front channels go to the db651s and the rear ones are bridged to the subwoofer.

Here's the problem: my head unit only has one pre-out and it's 2.2v. The amp has 2 RCA inputs so I split the signal into the 2 channels, meaning each is now only getting 1.1v.

I managed to adjust the gain on the amp channels to make it sound decent at low volumes but anything more than moderate levels makes the speakers cut out and return a second later with a slight fade in. My first thought was that the front speakers had a overload protection that cuts power to them if they're overpowered (speakers handle 55w RMS, amp is 60w, not a huge deal right?)

But then there is the possibility that the amp was doing the same thing. I don't know how much power that sub wants or what condition its in internally, could it be causing the intermittent sound loss?

This amp also has speaker-level inputs (optional for HUs that don't have pre-outs). My head unit puts out 14w RMS per channel, so I was thinking this is probably a better signal for my amp than a 2.2v signal that has been split, right? I'll probably try that next and adjust gain accordingly to see if it helps.

Click to read more...

 

[hatedonmostly 5,000+ posts]

Do you have the JL sub bridged on the two rear channels of the amp?

 

[lebowski]

Do you have the JL sub bridged on the two rear channels of the amp?

yup

 

[hatedonmostly 5,000+ posts]

The amp is probably only stable at 4 ohm when in bridged mode. The sub might be a single 2 ohm sub and the low ohm load is causing the amp to jump in and out of protect

 

[lebowski]

The amp is probably only stable at 4 ohm when in bridged mode. The sub might be a single 2 ohm sub and the low ohm load is causing the amp to jump in and out of protect

oh forgot to mention that, the sub box has a 4 ohm impedance sticker on it