Voltage drop question

[XPerties 10+ year member]

My setup is Polk components in front, rear polk all powered by rockford P400-4 along side a Memphis Shallow 12 sub 15-SC12D4 powered by Sony XM-ZR1252. This is installed on my back wall in a 05 Ford F150. The run from the battery is 8 gauge wire (I know, I know...I'm upgrading it to 4 gauge this week).

I've had the alternator bench tested with load and the battery is brand new Die Hard from sears (went with the largest they had). I've done the "big 4" on my truck using 0. I went battery to chassis, chassis to frame, frame to engine block and alternator to battery with 250amp inline fuse. I have a glo gauge volt meter connected directly to my batter and I run during normal operation 14.2-14.4 but if I put something that hits hard (mind you I'm not supplying the sub with hardly any power, thing is rated for 500rms and it's maybe getting 200) My voltage drops down to as low as 13 - 13.6 area.

Local stereo place told me to get a capacitor. After doing some searching on these forums I found several threads where you guys ripped the sh1t out of someone asking to buy one.

Based on my entire layout can you follow up with answers to:

[1] Do you think in my situation a capacitor would help?

[2] Do you think doing the upgrade from 8 to 4 on my power run would help this issue?

BTW I'm trying to replace that crap sony with a Cadence FXA-1700 Amp (if the member here is still selling it)...Just a FYI.

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[quins90lac 10+ year member]

You never get actual rms out of an amp, and dropping to 13 is nothing to worry about. Hell i drop down to 13.5 when im really on it and im pushing 1400 wats to my subs. But don't get a cap if any thing get another battery if you worried about it

 

[brmcm15 10+ year member]

13 isnt bad at all. when ur dropping to 11 and below, thats when u have a problameo

 

[1rockford1 5,000+ posts]

if u get a better amp im sure u well see better voltage, u have to understand 13.6 is not bad for the most part your car will idle at 13.8-14.2. what is your voltage at with the big 4 at idle no audio on etc??

 

[sexy 10+ year member]

13s are not bad at all as for getting another battery you better read this first.

SIGNAL TO NOISE: MAY/JUNE 2000

 

[Vossy 10+ year member]

13 volts is fine