Alpine KTP-445U settings/harness/input
I know there are some threads about this amp but I thought it would be easier to start one about the install and settings. So far this is what I have done.
Installed using Metra BT-5520 Harness. Cut RCA ends off KTP and used High level inputs (Speaker level). No remote wire attached because of the autosensing signal from speaker wire. Attached constant power wire from amp to harness which shares the HU power line. Originally used ground in harness but then moved to bolt in firewall. Gains are set to 1/4 (9 o'clock) position. Crossover is set 120hz because I have a powered sub. Anything below that didn't sound as clean.
Overall it sounds good. The only issue i have is a slight bit of noise/hiss. It is audible only when truck is off or in between tracks. Once you turn past 3 clicks it mostly fades away. I have been dealing with it for about 3 weeks now and really want to get to the bottom of this. Have read numerous posts from all kinds of forums and seems like it boils down to a few things.
1. Could be a grounding issue (I plan to set a new ground for Stock HU)
2. Line level input (Several experts feel it is hard to get rid of noise)
3. Low level input (RCA) (Some people have switched from line level to low level with LOC's and say the hiss/noise disappeared)
4. Stock HU is just crap and it might be the nature of the beast
If the grounding points don't solve the issue for me, I am willing to get back into it and go the RCA route but would rather not waste my time if it won't improve. Maybe, it's possibly the Metra harness. I'd also be willing to try the PAC harness it that works better.
I know most people would probably just deal with it but I'm a bit **** and would rather try several options to improve this than just settle for a system that is mediocre. Remove the noise and I would be 100% satisfied with it.
2009 F150 FX4 SCrew 4x4, 5.4L, 3.73