As happy as I am with my new system, I recently noticed a very, very high pitched noise (not engine noise, as it remains constant), almost like a very faint dog-whistle kind of sound at almost the upper range of hearing 18 khz to 20 khz.
This is a three week old system in a Ford Focus, it seems to be coming from the interior amp (Nakamichi PA-504); used the thickest and "best I could afford" possible wire (4) and made sure the ground was as perfect as possible. Does anybody have any ideas what can be causing it or what other things to check?
try to see if you move the RCA cables to the other side of car if it takes away the noise cuz sometimes if power is by the RCA wires it collets noise that might be it im not sure i hope it helped though
Well, the ground is good, signal wires are running on one side and power on the other. And, just to be be clear on this: the HU's output is shown in the manual as 0.7V and the amp has a range from 0.2 to 7.5 V
The best sound quality, although not volume, is available at what I roughly estimate to be the 0.7 V value and if I increase (or is decrease?) the amp's gain towards the larger numerical values, the noise goies away, but so do the sound AND quality. What does this tell us?
Can anything be done? - any advice is welcome and highly appreciated.
0.7? my god what a weak line voltage are you sure it wasn't 1.7 maybe? try getting a line driver to boost the signal to 4 volts. audiocontrol makes one.. it shouldn't be *that* expensive. a stronger line voltage will allow a cleaner signal to the amps and may fix this whole thing