JEEF
Member
- First Name
- Jeff
- Joined
- Jan 27, 2019
- Threads
- 0
- Messages
- 16
- Reaction score
- 43
- Location
- Southern California
- Vehicle(s)
- 2019 Wrangler Unlimited Rubicon; 2008 Audi S5; 1977 Chevrolet Blazer; 1960 Cadillac Coupe Deville; 1999 Chevrolet Silverado; 2017 Harley Davidson Softail Deluxe; 2013 Ducati Monster 1100 Evo; 2001 Honda XR650R;
@Sting_NC_USA
There’s a lot of good information there. Thank you for your help.
I realize that you don’t have the Alpine system.
I know I’m going to have to use some type of LOC. I’m just not sure which one yet. I’ll probably end up calling PAC and JL Audio and asking them some questions. I’m not sure when I’ll be able to get around to calling them, but I will definitely report back here with what I find out.
It does make sense that I would get all of the chimes, etc. through the JL Fix with it being installed after the factory Alpine amp. If it’s getting to the speakers, it’s going to get to the Fix.
On JL’s product page for the Fix units, it says they will except line-level, or speaker-level inputs. I’m just not sure what’s going on with the Alpine system and its separate amplifier.
When I look at the wiring diagrams that were posted on here somewhere, it appears that there are four audio signals coming out of the factory head unit and going into the amplifier. Left and right front and left and right rear. PAC’s product page for the Amp Pro says something about the head unit putting out fixed, line level signals to the amplifier and that the volume is controlled over CAN bus.
I know, I’m pretty obsessive compulsive about this type of stuff. LOL.
I know that a lot of factory audio systems (the alpine system included) do things like roll off the bass response as you turn the volume up. It may do other things as well like time alignment and I think that the EQ/sub level of the system changes when you remove the hardtop also. I think it changes when you unplug the connector at the back. I could be wrong about that though. I just thought I heard that somewhere on these forums. There may also be some loudness curve going on also.
I will probably end up having to get an RTA and check some of this stuff out, unless the guys at PAC and JL Audio know for sure what’s going on.
My hope is that the four signals coming out of the factory head unit are flat and level and that any processing of the EQ and that sort of thing is done in the amplifier. That way I could just use the PAC by itself as pull the signal before the amp. If not, I may have to do like you suggested in your response to my #4 and use the Amp Pro and feed that signal into a Fix to level out the system EQ and any time alignment, phase stuff, etc.
I really don’t want to use the Fix after the amplifier. I know for a fact that the bass is rolled off when you turn the volume up and I would really like to use my factory volume knob. I don’t want to have to set my volume to the point right before the bass rolls off in order to calibrate the Fix and then use the Fix or DSP volume knob. If I can pull the signal before the amplifier (if that is where the factory processing is taking place) then I think that would be a better way to go to get a clean signal for my processor/DSP.
I’ve been looking into the TWK processor a little bit more and I don’t think that you can use them with the VXi hub. The VXi amps have 2 JLid ports on them. Comm and Control. The Fix units only have one for control. That’s a bummer. I’m sure their marketing department came up with that idea. They want to push you into the VXi amps. I do think you can use 2 TWK units together, you just have to adjust them in 2 separate Tün sessions and use one knob for each unit to change presets. I’m just not sure if the audio signals going into them would come out timed perfectly. The VXi hub synchronizes the digital clocks in those amplifiers.
Like I said, I’m kind of obsessive about this sort of thing. i’m just going to have to call JL.
I should probably just use the VXi amps. They are just so expensive and won’t quite put out the power that I was hoping to run in this system. not for the subs anyway. I may just have to dial it back a bit for the sake of convenience.
I think these VXi amps are about the coolest things out right now. JL knows that and that’s why they get so much for them.
I wish they made some larger monoblocks that looked like the VXi amps, but without the processing since you can already send a processed signal out of the multi-channel ones.
Thanks for the link to that thread by @NYknowledge. I’ll look into that Metra AX-DSP-X unit as well.
I’m not sure if what I’m looking to do is going to be possible or not. I just want a clean, flat signal from the factory head unit that doesn’t have any time alignment, bass rolloff, or any other funny stuff going on, but still has the factory chimes, nav audio, etc.
Thanks again and I’ll report back whenever I have any more info.
-Jeff
There’s a lot of good information there. Thank you for your help.
I realize that you don’t have the Alpine system.
I know I’m going to have to use some type of LOC. I’m just not sure which one yet. I’ll probably end up calling PAC and JL Audio and asking them some questions. I’m not sure when I’ll be able to get around to calling them, but I will definitely report back here with what I find out.
It does make sense that I would get all of the chimes, etc. through the JL Fix with it being installed after the factory Alpine amp. If it’s getting to the speakers, it’s going to get to the Fix.
On JL’s product page for the Fix units, it says they will except line-level, or speaker-level inputs. I’m just not sure what’s going on with the Alpine system and its separate amplifier.
When I look at the wiring diagrams that were posted on here somewhere, it appears that there are four audio signals coming out of the factory head unit and going into the amplifier. Left and right front and left and right rear. PAC’s product page for the Amp Pro says something about the head unit putting out fixed, line level signals to the amplifier and that the volume is controlled over CAN bus.
I know, I’m pretty obsessive compulsive about this type of stuff. LOL.
I know that a lot of factory audio systems (the alpine system included) do things like roll off the bass response as you turn the volume up. It may do other things as well like time alignment and I think that the EQ/sub level of the system changes when you remove the hardtop also. I think it changes when you unplug the connector at the back. I could be wrong about that though. I just thought I heard that somewhere on these forums. There may also be some loudness curve going on also.
I will probably end up having to get an RTA and check some of this stuff out, unless the guys at PAC and JL Audio know for sure what’s going on.
My hope is that the four signals coming out of the factory head unit are flat and level and that any processing of the EQ and that sort of thing is done in the amplifier. That way I could just use the PAC by itself as pull the signal before the amp. If not, I may have to do like you suggested in your response to my #4 and use the Amp Pro and feed that signal into a Fix to level out the system EQ and any time alignment, phase stuff, etc.
I really don’t want to use the Fix after the amplifier. I know for a fact that the bass is rolled off when you turn the volume up and I would really like to use my factory volume knob. I don’t want to have to set my volume to the point right before the bass rolls off in order to calibrate the Fix and then use the Fix or DSP volume knob. If I can pull the signal before the amplifier (if that is where the factory processing is taking place) then I think that would be a better way to go to get a clean signal for my processor/DSP.
I’ve been looking into the TWK processor a little bit more and I don’t think that you can use them with the VXi hub. The VXi amps have 2 JLid ports on them. Comm and Control. The Fix units only have one for control. That’s a bummer. I’m sure their marketing department came up with that idea. They want to push you into the VXi amps. I do think you can use 2 TWK units together, you just have to adjust them in 2 separate Tün sessions and use one knob for each unit to change presets. I’m just not sure if the audio signals going into them would come out timed perfectly. The VXi hub synchronizes the digital clocks in those amplifiers.
Like I said, I’m kind of obsessive about this sort of thing. i’m just going to have to call JL.
I should probably just use the VXi amps. They are just so expensive and won’t quite put out the power that I was hoping to run in this system. not for the subs anyway. I may just have to dial it back a bit for the sake of convenience.
I think these VXi amps are about the coolest things out right now. JL knows that and that’s why they get so much for them.
I wish they made some larger monoblocks that looked like the VXi amps, but without the processing since you can already send a processed signal out of the multi-channel ones.
Thanks for the link to that thread by @NYknowledge. I’ll look into that Metra AX-DSP-X unit as well.
I’m not sure if what I’m looking to do is going to be possible or not. I just want a clean, flat signal from the factory head unit that doesn’t have any time alignment, bass rolloff, or any other funny stuff going on, but still has the factory chimes, nav audio, etc.
Thanks again and I’ll report back whenever I have any more info.
-Jeff
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