My vehicle is a 2015 Honda Civic LE.
Does anyone on here have any specific insights on any issues with a static/distortion noise when feeding a Helix DSP with the non-navigation, touchscreen, factory HU using the high level inputs?
I've set the inputs, outputs, and crossovers so far. I was about to start testing to correct the factory signal using correlated pink noise using the Input Signal Analyzer. Before using the Input Signal Analyzer I popped in an audio CD, Diamond Rio, at low volume, 10 on the volume scale, on the HU and it is way louder than before.
The voltage reading I have with the high level inputs is 6.2v AC. I also verified this setting with an oscilloscope. Max undistorted volume on my HU is 29. (It is actually 30, but I wanted some breathing room, just to be safe).
Under the DCM menu, in the Audiotec Fischer DSP PC Tool v5.06.02, I found the best setting for the Input Gain to be 5.5Vrms, the next option just below clipping. This DSP does not have the adjustment knob and clipping light on the housing of the DSP. Input Gain is set in the software.
Without doing any EQ or using the RTA function, I am getting a static noise from the speakers. It sounds like minor distortion. My ground is solid. I ran my power and signal cables on opposite sides of the vehicle. I haven't set any of the gains on the amps yet. I'm afraid if I do so that I will damage the speakers.
I've measured voltage, from the battery, to every link in the power chain for the system, and back to the battery and that all looks good. I grounded the ground distribution block to one of the bolts behind the back seat, after sanding it to shiny metal. I'm not sure what is inducing the noise?
My setup (a very modest system):
HU: Factory, non-navigation, touchscreen head unit front right and left high-level inputs to the Helix DSP .3S.
Wiring: (Knu Konceptz)
4-8 Gauge Mini ANL fuse holder
Power and ground (Kolossus Flex 4 gauge for main power and ground / 8 gauge for both amps)
Signal, power and ground for the DSP (18 gauge)
Speaker wire (16 gauge for the speakers 12 gauge for the sub.
RCA cables (Krystal),.
Distribution Block:
Stinger (x2) - 2x 4 gauge in / 4x 8 gauge out
WUPP 12 Volt Fuse Block (for the DSP's 3A fuse)
Speakers:
Herts C26 tweeters running active
Hertz C125 mid-bass drivers in the factory door locations
JL Audio CP112-W0v3 single 12" sub in the trunk.
Amps:
Sony XM502X: 2 channel amp (Wired mono for 160w RMS)
Sony XM504X: 4 channel amp (50w RMS per channel)
DSP:
Helix DSP .3S
Crossovers for these drivers, set in the Helix DSP are:
Tweeters: 2500khz for highpass / no lowpass filter
Mid-Bass: 80 Hz highpass / 2800Hz lowpass
Sub: no highpass filter / 80 Hz lowpass
