Wiring HELIX V EIGHT DSP MK2 from headunit in 2018 EX-T

[triplehelix]

this is my first audio system install and i'm a little confused on what to expect when i pull the headunit, and how to proceed once i do. i believe my car has a factory amp installed but have seen people saying the "without amp" pinout is used for all aftermarket wiring. these are the two pinout diagrams i'm looking at:

https://www.civicx.com/forum/attachments/screenshot_20210614-123015_chrome-jpg.297115/

which pinout should i use? if its the "with amp" version, which wires do i tap into for the high level inputs to the DSP/amp? what is the voltage coming from these wires as i need to set the jumpers inside the DSP ( https://www.audiotec-fischer.de/media/pdf/3c/86/6c/HELIX-V-EIGHT-DSP-MK2_Web.pdf page 28-30 with chart on 32, any clarity here is much appreciated).

is there anything else i should do, like disconnect the factory amp, disable anything, adjust any headunit settings or anything to make for a better audio experience?

many thanks in advance for any assistance getting this installed.

Sponsored

 

[triplehelix]

bump, hoping someone can tell me if i have the amp or not (so which diagram to us) or which wires to tap into.

 

[bikejog]

If you have an ex-t then you do have the external Amp. But both diagrams you linked to are not the correct ones. I think before you start, you should do some r&d about the system first. Below is a good starting point. Not 100% correct, but all the basics are there.

https://www.civicx.com/forum/threads/2018-premium-audio-system.33835/

 

[triplehelix]

awesome, thank you. i had been reading a bunch but i guess not getting what i was reading. will dig through that thread.

 

[triplehelix]

that thread is referencing a center channel and sub, which i do not have installed stock. i have 8 speakers, 4 tweeters, 4 6.5", which i thought means i don't have the premium audio which was why i thought the diagrams i posted were the ones i needed.

edit: i think its because i have a sedan which is the 8 speaker system, and the coupe has the 10 speakers. still completely lost on which wiring diagram i should be working off of to see which wires i need to tap into.

 

[bikejog]

I just looked at Honda owner website and you're correct, the ex-t doesn't have the premium system. Seems like for sedan/coupe, only the Si and touring has the premium.

https://owners.honda.com/vehicles/information/2018/Civic-Sedan/specs#mid^FC1E3JJW

 

[triplehelix]

this is the circle of reading/research i was in that led me to posting this thread. i had found a thread where OP had deleted his original post that seems to have been exactly what i needed, but not finding any other info for exactly what i need and that poster hasn't posted in almost 3 years. i thought i found another thread that had me moving in the right direction where i grabbed the diagrams i posted originally, but i guess not?

really i just need to know where i should be tapping into the wires (back of the head unit or after amp seems to be the choices) and a pinout/diagram or key so i know which wire is which. i can test the voltage with a multimeter if the volts of whatever wires i'm tapping into isn't available and figure out the DSP/amp stuff from there.

 

[bikejog]

Well since no one with knowledge of your system is here any more, I'll give it a shot. Keep in mind I'm not as familiar with your system as my Premium System.

• Diagram. You need a 'without amplifier' diagram since you do not have an external amp. I cannot confirm if the one you linked is the correct one since I do not have the service manual with me at the moment. I'll confirm it tonight at home.
• What to tap. In the Premium System, most people tap into the front left and right channels since the rear output is dumbed down and really is just used as fill. I think people with non-premium systems do the same: tap the front channels only. Assuming the diagram you linked is the correct one, you need to tap the the front left and right channels labelled as FL SPKR+/- and FR SPKR+/-.
• Where to tap. In the Premium System, the external amplifier is located in the passenger kick panel so it's easier to tap after the amplifier there. Not sure where's the best location for you to tap in your non-premium. The two obvious choices are get an adapter for the back of the HU or tap where the front door speaker wires enter the cabin. Not sure if there's a better location.
• Which DSP input to use. You need to use the high level inputs. I read the doc on your DSP and it said the default high level max input range is 18V (peak??) and 25 watts RMS. These two figures don't exactly match, but they probably were conservative with the watts RMS figure. 18V peak is about 31 watts RMS into 4 ohms. Your Civic is 180 watts peak. Assuming that figure is into 4 ohm , then 180 / 4 speaker channels = 45 watts peak / channel = 45 * 0.707 = 31.815 watts RMS. So I think you're safe to leave your DSP's input jumper at the default. I don't think the Civic can ever hit anywhere near 20 watts RMS / channel IMO. You may want to r&d on that.

An extra tip for you is to look up "DSP Flat" in the factory menu. When "DSP Flat" is active, the HU will bypass the factory EQ curve and output a flat signal. The only problem, I think, is "DSP Flat" reverts to inactive on every startup so you may also need to get Honda Hack to keep it permanently active.

 

[triplehelix]

• Diagram. You need a 'without amplifier' diagram since you do not have an external amp. I cannot confirm if the one you linked is the correct one since I do not have the service manual with me at the moment. I'll confirm it tonight at home.

that would be awesome!

• What to tap. In the Premium System, most people tap into the front left and right channels since the rear output is dumbed down and really is just used as fill. I think people with non-premium systems do the same: tap the front channels only. Assuming the diagram you linked is the correct one, you need to tap the the front left and right channels labelled as FL SPKR+/- and FR SPKR+/-.

i got the crutchfield 9 wire cable and the helix i have does signal summing on up to 8 high level inputs so i was going to run all 4 inputs (front l+r, back l+r) and let the dsp do its summing to make sure i don't lose any signal. is it preferable to only do the two front inputs for some reason? at some point after more reading i was thinking of make the back pure fill using a technique of swapping wires on the back speakers i read on diymobileaudio, but i don't really understand the method or full purpose and have way more reading/learning to do on basic calibration with REW and a calibrated mic so thats something for the future.

• Where to tap. In the Premium System, the external amplifier is located in the passenger kick panel so it's easier to tap after the amplifier there. Not sure where's the best location for you to tap in your non-premium. The two obvious choices are get an adapter for the back of the HU or tap where the front door speaker wires enter the cabin. Not sure if there's a better location.

ended up calling my local honda dealership before i saw your post and they confirmed i do not have the amp, so i'll be tapping into the wires right behind the headunit. the guy that ended up being able to answer my question was at the parts counter so couldn't tell me anything about the pinout. unfortunately i couldn't find any t-harness adapters sold on their own so will be using posi-tap's to tap into the wires.

• Which DSP input to use. You need to use the high level inputs. I read the doc on your DSP and it said the default high level max input range is 18V (peak??) and 25 watts RMS. These two figures don't exactly match, but they probably were conservative with the watts RMS figure. 18V peak is about 31 watts RMS into 4 ohms. Your Civic is 180 watts peak. Assuming that figure is into 4 ohm , then 180 / 4 speaker channels = 45 watts peak / channel = 45 * 0.707 = 31.815 watts RMS. So I think you're safe to leave your DSP's input jumper at the default. I don't think the Civic can ever hit anywhere near 20 watts RMS / channel IMO. You may want to r&d on that.

awesome. i knew i had to use the high levels but didn't know what jumper configuration i needed because i am not familiar with the voltage math you laid out there. i will check with another source on the jumper configuration to make sure as you suggest.

• An extra tip for you is to look up "DSP Flat" in the factory menu. When "DSP Flat" is active, the HU will bypass the factory EQ curve and output a flat signal. The only problem, I think, is "DSP Flat" reverts to inactive on every startup so you may also need to get Honda Hack to keep it permanently active.

i did come across the DSP Flat in my search for answers before posting this thread and the issue of it reverting everytime you shut the car off. the idea of hacking the system made me a bit nervous though. outside of the normal "everything has risk" level, is it pretty safe?

thank you so much for all your assistance here.

 

[bikejog]

Couldn't verify the diagram you linked 'cause the link's broke. But I think it was correct for the speaker wires.

Turns out there're three different diagrams for Connector A. I think it's because one's for Hatch, one for Sedan/Coupe with XM (shark fin antenna), and one for Sedan/Couple without XM (window antenna). But the speaker wires are all in the same locations for all three. You should be able to find which one matches yours by matching wire colors.

 

[bikejog]

i got the crutchfield 9 wire cable and the helix i have does signal summing on up to 8 high level inputs so i was going to run all 4 inputs (front l+r, back l+r) and let the dsp do its summing to make sure i don't lose any signal. is it preferable to only do the two front inputs for some reason? at some point after more reading i was thinking of make the back pure fill using a technique of swapping wires on the back speakers i read on diymobileaudio, but i don't really understand the method or full purpose and have way more reading/learning to do on basic calibration with REW and a calibrated mic so thats something for the future.

Sorry, I was confused with what you're doing and what people do to tap a Sub channel. For Sub, you only want to tap the fronts. For what you want to do, you're correct that you want to tap all four channels. However, since your HU outputs full range signals for each channel, I'm not familiar with what benefit will gain by summing those channels. Summing is usually used in systems where the high and low frequencies, for one channel, comes out of different amplifiers (like those in the Premium System). In your system, each amplifier outputs the full range frequency. So if you sum the L and R channels, then you get mono. If you sum the front and rear, then it will suck. You don't usually sum different channels. You sum the different frequencies for each channel. I think all you do in your setup would be to tap all four, adjust the EQ to your liking, and feed those 4 to 4 two way speakers.

Ah, "swapping wires", you could be referring to Dolby Pro Logic surround sound. The source must be encoded to take advantage of that. Most analog movie soundtrack are encoded with some version of that, but music are usually not.

ended up calling my local honda dealership before i saw your post and they confirmed i do not have the amp, so i'll be tapping into the wires right behind the headunit. the guy that ended up being able to answer my question was at the parts counter so couldn't tell me anything about the pinout. unfortunately i couldn't find any t-harness adapters sold on their own so will be using posi-tap's to tap into the wires.

IIRC, there should be adapter available for non-premium systems. There was even a guy on here that makes and sells harness.

awesome. i knew i had to use the high levels but didn't know what jumper configuration i needed because i am not familiar with the voltage math you laid out there. i will check with another source on the jumper configuration to make sure as you suggest.

You could check the max power output of your Civic if you have a DMM or better, a scope. Make some 1 KHz pure sine mp3 loops and make the audio level as high as possible. Play that on the HU, adjust the volume until just before clipping (more accurate with a scope) and measure the voltage to the speakers with a DMM. And if it's < 18 V peak, then you're "In Like Flynn". Make sure you know if the DMM is measuring peak or rms. You can convert between the two with the following formula.

. You could probably also use the built-in audio check function in the secret factory diagnostic menu. The audio check cycles a 1 KHz ( IIRC ) pure sine tone on each individual speaker.

i did come across the DSP Flat in my search for answers before posting this thread and the issue of it reverting everytime you shut the car off. the idea of hacking the system made me a bit nervous though. outside of the normal "everything has risk" level, is it pretty safe?

I have seen posts of people having problem with Honda Hack. I haven't hack mine yet cause I have no need for it. However, I assume rooting the unit without installing Honda Hack will probably be completely safe. Honda Hack started out as a free diy jobby. Instructions for the free root method is still out there. Not sure if it still works tho. I assume if you do the free root procedure and create a shell script that activates DSP Flat on every boot up, then it will be perfectly safe as well. Of course, there're still unknown risks that you'll be taking. Risks like, how long to wait before it's safe to issue the Activate DSP Flat command. Could you hang the system if you issue this command too early, or could your script run in an inopportune time that could cause a race condition with other system applications? Those are the risks that you will be taking. But then if the HU is rooted, then you could probably recover it if it hangs.

 

[PandaXpress]

I have a 2016 EX-T which is the same, I am also running Honda Hack and viper4android to get ride of the stock bass roll off in our system. I just rewired my audiocontrol DM-608 DSP to take high level inputs instead of RCA inputs. We do not have an amp and you need to tap outputs from the radio, Do you have a T Harness? That would make life so much easier.

I actually did not sum all the channels i only summed the Front and the rear sperately because i think it messes with the andoidauto navigation volume

 

[triplehelix]

super busy couple weeks and had to put this aside till now.

bikejog, here's the backfill technique i was talking about:

https://www.diymobileaudio.com/threads/hey-werewolf-confusion-about-l-r.22523/#post-242720

the helix has a bass restore function i'm going to try before i venture into the honda hack. i'm going to get some feedback on the jumper setting for the voltage and attempt a read with the multimeter and report back my findings.

bike/panda, no t-harness. i have searched for one but have not found one on its own. if you have a source i would definitely be my preferred method rather than tapping those small wires.

 

[Tw1tcHy]

OP,

I too have an '18 EX-T and I'm also strongly considering purchasing a Helix V Eight Amp/DSP. It will also be my first install. Just curious, what made you go with such a sophisticated piece of hardware for your first time? What's the rest of the system composed of?

I've been poring over wiring diagrams for the car, trying to be as prepared as I can before I pull the trigger and order more stuff. I only want to do this once and I want to do it to the best of my ability.

I attached two sets of diagrams below. One is the raw, unedited wiring for the 2018 Sedans with and without the factory amplifier, while the highlighted one is one I just now marked up real quick to have the factory amplifier and it's associated wiring out of the way to make it a bit easier to read. My car has the XM (shark fin) antenna and no factory navigation, so I marked that up accordingly, but there's likely a few things I overlooked since it was hastily marked up. Is this basically what you were looking for? I have access to any and all diagrams, most of them colored as well. Let me know!

 

[bikejog]

bikejog, here's the backfill technique i was talking about:

https://www.diymobileaudio.com/threads/hey-werewolf-confusion-about-l-r.22523/#post-242720

Ah, that's just Dolby Surround (see Post #13 from your link, also showed below), which is the predecessor of Dolby Prologic that I mentioned previously. Here's a link on how to decode Dolby Surround just by moving the speaker wirings around ( but this will not sound as good as using a hardware Dolby Prologic/Prologic 2 Decoder). See Sections "Four From Two" and "Phase Shift". https://electronics.howstuffworks.com/surround-sound.htm.

As I said, Dolby Surround/Prologic/Prologic-2 needs proper encoding for best results. For example, the audio engineer would only encode something like a helicopter flying overhead or a bullet flying above your head or from front to rear, but would not encode a car that goes from left to right in front of you, etc. The posts you linked to looks to me like just trying to blindly encodes EVERYTHING from the two channel source into a Dolby Surround like signal. Not sure if the result will be satisfactory. Perhaps will help the ambiance a little? But can't help but think that might also hurt for some program materials, but I'm not sure. But do try it and report back please.

Now I'm wondering what the stock "Surround" decoder on the Premium System is? Could it just be a Dolby Prologic or Prologic 2 Decoder? I'll have to play the first "Top Gun" movie and see if the jets sounds move from front to back and forth like it should. I doubt it given how the stock system decodes the center channel.

Sponsored