PCCM+ White Noise
07-13-2024, 05:11 PM
#16
I have also tried many different options to try and solve the white noise, it seems you have been down a similar path.
I tried one of the these variable attenuation step downs, but they are designed to output a phono level, and the ASK amplifier is unusual in the it takes speaker level input: “Connects LP3-4 LocPRO Series 4-Channel Line Output Converter for OEM or Aftermarket amplifiers”
Both the Connects2 LP3-4 LocPRO and the CTAMPASSTHROUGH are a complete impedance mismatch with way too much attuation and the audio quality is dreadful.
Regarding the in-line resistors:
I tried 4ohm, 8 ohm and 12ohm. It needs 12ohm to work well with the 0-30 volume range.
Sound quality is excellent, using USB with mp3 at 256-bit.
No problems with heat, I did trial 8 resistors at 6ohm, as I too was worried about heat. But 8 resistors is quite bulky.
The quoted unit 45W x4 will be peak, converting to RMS, it is more like ~30 watts per channel.
You can get higher wattage resistors, 50 watt, but they are bulky.
I tried one of the these variable attenuation step downs, but they are designed to output a phono level, and the ASK amplifier is unusual in the it takes speaker level input: “Connects LP3-4 LocPRO Series 4-Channel Line Output Converter for OEM or Aftermarket amplifiers”
Both the Connects2 LP3-4 LocPRO and the CTAMPASSTHROUGH are a complete impedance mismatch with way too much attuation and the audio quality is dreadful.
Regarding the in-line resistors:
I tried 4ohm, 8 ohm and 12ohm. It needs 12ohm to work well with the 0-30 volume range.
Sound quality is excellent, using USB with mp3 at 256-bit.
No problems with heat, I did trial 8 resistors at 6ohm, as I too was worried about heat. But 8 resistors is quite bulky.
The quoted unit 45W x4 will be peak, converting to RMS, it is more like ~30 watts per channel.
You can get higher wattage resistors, 50 watt, but they are bulky.
07-13-2024, 06:14 PM
#17
Cruisin'
Join Date: Aug 2023
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I’ve put the unit back together now, I will try and post a video clip when I get a chance, I have the before with white noise, I need to record a demo after to show audio quality and when unit is muted, white noise removed (allowing for the fact my phone is recording the whole process).
