During high-volume playback (meaning with volume at like 37, 38 or 39 out of 50) when I focused on a particular song for troubleshooting this issue (so I'd have a constant thing I could use to measure whether a new step I tried had a positive effect) the outpu of the highs+mids (aka the 4ch amp) just dims-out, fades down.
When this happens I can turn the volume back down to like maybe 34 and you can hear the highs+mids slowly start creeping back up until they return to what they should sound like.
It's not the gains. I tuned them individually (meaning 4ch amp was tuned with the SUB output set to ATTenuate so I could hear the 4ch amp playing solo). For the 4ch amp I tuned the gains to sound as high as they could before distorting with volume at like 38 with no eq settings whatsoever.
From what I understand and have figured out from reading a buttload of forums, this symptom sounds like an issue related to power delivery to the 4ch amp.
Because of this issue I decided to add a 2nd battery HC600 out back behind my rear seats near the amps.
It is also because of this issue that I did the Big 3 upgrade to 4 Gauge Monster Cable.
It is also because of this issue that I returned a JENSEN Power 760 and decided to go with a more name-brand amp instead thinking at first the JENSEN was more than likely the culprit since it's sort of a lesser brand.
It is because of this issue that I went back and also ran the 4 gauge ground wire in Parallel (as well as the power I initially did) from starter to 2nd battery per Kinetik's instructions.
This problem is annoying as all get-out!! Spent 2 hrs searching these forums. Did not find anything similar enough to my issue to give me some insight so posting my question.
2002 Ford Explorer SportTrac
Stock Alternator (130 Amp)
Big 3 done (w 4 gauge).
Starter Battery = DuraLast Gold (Autozone less then year old)
2nd Battery Kinetik HC600 (Wired in Parallel w 4 Guage with StarterBattery)
4 Gauge off 2nd battery Pos+ to Non-fused Distribution Block
2 (no name) short 4 Gauge pieces from Dist Block to both amps.
4ch amp Grounded to 2nd Battery. (previously to chassis w same problem occuring)
Mono amp Grounded to Rear Seat Bolt.
Headunit = Sony CDX GT630UI (Problem occurs CD or USB)
4ch Amp = Pioneer D9500F (same symptoms w Jensen Power760 I tried before this)
Mono Amp = HITRON HA.1000-1 (Has always played fine)
Most of the ring terminals involved are the nice Allen-wrench cinch kind (either Monster 300 series, of Stinger Gold-Plated) except for maybe 2 of the Big 3 wires (which are Monster 200 series crimps). All but one of the crimped connector (all done in table-vise) were also soldered rapidly via Propane Torch w same Flux I used for my Copper plumbing in recent bathroom remodel. I think Alternator Pos+ (not Monster 200 series) was the only one just crimped w/out solder and the connection to battery side is nice Allen-wrench kind.
NOTE: Finsihed Alternator Case to Frame chassis of Big 3 upgrade this evening. It seems my car idles a teeny bit higher/better now and I'd swear the lights look brighter. but the issue STILL happens with the 4ch amp output!!!
NOTE: Things that come to my mind to possibly try at this point are...:
- Perhaps NOT connect 4ch Ground to 2nd Battery Ground since Mono amp is not connected to 2nd Battery but connect to Rear Seat anchor bolt and seems to do fine.
- I DO NOT have the speaker-wire to the 4 doors fully upgraded to thicker stuff. I only used aftermarket speaker-wire to connect from where I cut the wires.... to run back to amp.. then run back to the other side of where I cut the wire to then let the factory wire that was there feed the power into the speakers in the doors. The outpu of the 4ch Pioneer is CEA Compliant 75 W RMS per channel. Even with the skinny wire from factory is SHOULD be able to hang with this.. right? I mean... it does sound kick-*** for those 30-40 seconds where it's playing back the music at full-tilt volume.
- Replace Starter Battery with an AGM battery of some kind? I was thinking Kinetik 1800 but since then I have read a thread where a gentleman with a 2003 Explorer said it was too tall and he couldn't close his hood.
- Replace Mono amp with a Class D amp to draw less power perhaps?
Any insight, or thoughts on what to look at, test, or try next would be Greatly appreciated. Thanx.