Line Level adapter Help.

[RMDecker]

My GF has a a 2019 Jeep JLU Wrangler with the standard head unit. We wanted to insall a sub and amp yet keep the stock head unit for the time being. Also for theft reasons as its often without the doors. (the cargo area locks). I have installed the SoundQubed Active 5-Channel Car Audio Line Out Convertor. https://soundqubed.com/q-loc5-active-line-out-converter/ . Ive cut the wires that come from the head unit to the speakers and run them to the line out converter. Then the amp to the speaker wires. With the converter installed nothing plays from the head unit speaker outputs. What I have discovered is on power up the head unit looks for a resistance from the speakers before turning on that channel. If I bridge the input (line out of head unit) with a speaker (creating load) then the channel turns on and outputs to the line out converter and it plays through the amp as it should. I can remove the speaker once it starts playing and it will continue playing. On restart of the stereo rechecks for a load so it disables the channel. I was thinking of bridging the inputs with a resistor to create a load but im not sure how it would effect the sound and what size resistor to install. At first I was thinking speaker ohm (4) but then the resistor would have to dissipate probably 20w (head unit wattage). I was thinking a higher value resistor would have to dissipate less energy and effect the sound less. Can anyone tell me what effect a resistor will have on the sound and their thoughts on the value of the resistor?
amplifier is an Audopipe 5ch amp and it doesn't have line level in.

Click to read more...

 

[1aespinoza 10+ year member]

Can anyone tell me what effect a resistor will have on the sound and their thoughts on the value of the resistor?
amplifier is an Audopipe 5ch amp and it doesn't have line level in.

It has no effect on audio quality. I use these load resistors parallel on the radio out.

 

[RMDecker]

Interesting, I suppose it would act like a speaker in parallel. What about using a higher ohm value to so I don't have to dissipate the heat of so many watts? By ohms law 40w 12v 4ohhm speakers. But if you had a 16 ohm speaker @12v you would have only approximately 10w.

 

[Jimi77 5,000+ posts]

Interesting, I suppose it would act like a speaker in parallel. What about using a higher ohm value to so I don't have to dissipate the heat of so many watts? By ohms law 40w 12v 4ohhm speakers. But if you had a 16 ohm speaker @12v you would have only approximately 10w.

You could try a higher ohm value, but nobody knows what value will kick on the outputs, so you'll be experimenting. I guess you could get 4x4ohm loads and wire in them in series and see if that works. If it doesn't you can keep pulling resistors until it does work.

 

[1aespinoza 10+ year member]

Interesting, I suppose it would act like a speaker in parallel. What about using a higher ohm value to so I don't have to dissipate the heat of so many watts? By ohms law 40w 12v 4ohhm speakers. But if you had a 16 ohm speaker @12v you would have only approximately 10w.

I never thought about that. I have not even pondered to feel the resistors. Maybe like Jimi77 stated, the radio may assume the higher resistance as a speaker failure and not kick on.

 

[RMDecker]

only one way to find out. thanks for the input.