vtec4me21

I have been reading a bit on how to bypass the OEM amp. in my 2011 Acura TSX 4cyl. auto. with the base sound package of seven speakers. I would like to keep the OEM head unit and connect a JBL MS-8. This will connect to a five channel amp to power a pair of components running active and a single sub. It seems the pre-amp signal is flat without equalization, and although the MS-8 can use a post amp signal, I don't like the idea of the volume difference when switching sources such as from CD to USB, etc.

I've read about making an RCA cable to run the balanced pre-amp lines to the MS8. I would use the instructions here: http://www.rane.com/note110.html and the #24 option.

The RCA patch cable will be under two feet so hopefully noise won't be introduced. I'll be using two wire microphone cable.

Questions:
- Has anyone had experience with this configuration with these models of Acura / Hondas? I think the 8th generation Accords also have the same signal from the OEM head unit.
- I read about a Mercman harness, but it seems this isn't possible to get anymore?
- I assume there is a chance of introducing noise by doing this, but if I solder the shield of the OEM cable to the RCA for that side of the connection and leave it unsoldered on the MS8's input side that would work correct?

skathe

ive got an ms8 installed post amp, my input wire harness to the factory amp wasnt color coded and i dont have enough experience to create a bypass harness but hey thats what the ms8 is for.

mercman harness is for 1st gen but i have been messaging with another member on here that did the install too and bypassed factory amp, will see if i can get them on this thread.

The ms8 is built to handle input/output connections from rca or direct speaker wire. The base model speakers is 2 front door speakers, 2 front tweeters, 2 rear speakers and a subwoofer. the ms8 handles 8 channels so you should be able to run all of those directly to the ms8. simply identify and separate each channel pre amp and wire accordingly.

vtec4me21

Thanks for your help skathe. Yeah, I was planning on using the FL and FR pre-amp lines, solder the (+) to an RCA center pin and the (-) to the RCA ground ring. I'll also solder the shielding from the OEM amp pre-signal harness (The B harness) to the RCA shield.

Also as you mentioned I can wire up the MS-8 to the post amp harness, and that is certainly an option. Here's some info. I've gathered from various posts about the MS-8.

About the HU line level outputs: The audio lines out of the Accord HU are a “balanced pair” or “differential output”. This means that there are 3 wires per audio line – signal (+), signal (-), and shield ground. Neither of these 2 “signal” wires should ever directly be connected to a common ground – this can (at best) cause excessive noise or (at worst) cause a HU output overload & failure. So, the balanced audio line needs to be, 1) connected to a 3 wire balanced input device, or 2) the 3-wire line needs to be adapted to a “single ended” common ground 2-wire signal (usually done with an isolation transformer). Fortunately, the MS8 RCA inputs are “quasi balanced” and isolated (not common grounded) and they can be used directly from the HU with a special wiring consideration.

And that consideration is: The 3-wire (shielded pair) continues from the HU to the termination (other end) were the (+) wire is connected to the RCA center pin, the (-) wire is connected to the RCA ground ring, and the (shield) wire is not connected to anything at all. My custom audio line harness also passes the 12V, Acc, steering wheel remote signals, and ground to the HU. To do this without cutting the cars harness, I bought a male and female version of the main (largest) HU connector. These two are connected somewhat “back to back”: The 12V, Acc, and ground are connected from one to the other, but the L&R audio and trigger lines break and continue toward the MS8.

You don't need to know when the head unit clips with an MS-8. If you're using a factory head, MS-8 will help you set the volume at an appropriate level for un-EQ. Set the amps to 2V initially, calibrate with the microphone according to the owner's manual (with MS-8's volume control set at -20 or lower. Then, increase MS-8's volume control to -6 to -9 and you can use your radio's volume control if you prefer. if there isn't enough level with MS-8's control set to -6, then increase ALL the amp's gains equally until it plays as loud as you want it to and doesn't have more hiss than you can tolerate.

No scope, no meter, no test tones, just follow the instructions.

BlackNsexy2010

Another ms8'r.. Welcome man..I just put one of these in too..like skathe I put it post amp because I don't know enough to do it before it .. In your second post you mention you will use fl and fr .. Will you not be using the sub signal as we'll?

vtec4me21

Thanks for the welcome, I have been reading about the MS8 installs here and other places and saw your thread.

From what I've read the pre-amp FL and FR are full range signals and the MS8 instructions say using an RCA input that's all you need. So that would work for the sub. channel as the MS8 will split the signal depending on how you assign the output channels.

Now, using the post factory amp connection you need all the speaker level connections as the MS8 combines (sums) all those and in the end you get a flat line level signal to send to your aftermarket amp(s). That is because the amp does eq. for each of the inputs such as CD, XM, etc. The pre-amp signal is supposed to be flat as all the eq. is done by the OEM amp.

BlackNsexy2010

I gotchu.. I just reread them.. Front full range with aftermarket headunit ( fl mid fl tweeter fr mid fr tweeter) or with factory head unit front full range plus sub.. How is your adapter coming along?

And in terms of volume If I ever need to adjust it I just click the remote ..it's not a big deal.. I have mine turned up and usually the headunit works fine in terms of controlling it.. You don't need to point it anything just click up or down for the volume with the remote

vtec4me21

I'm waiting for parts to arrive so I can solder the RCA connectors to the pre-amp wiring. Hopefully I'll get all this installed this weekend, or at least most of it. I want to take my time with this install and do it right the first time, so no shortcuts.

Ah, okay I see what your saying about the MS8 remote and using the head unit to fine tune the volume.

I posted this question on DIY mobile audio forum and a previous JBL engineer (I think so anyways) stated that soldering up the pre-amp to RCA just needs the positive and negative from the FL and FR and not the shielding. I feel confident in what he said as the JBL MS-8 thread is very long and has a lot of information in it.

BlackNsexy2010

If u can try to snap up some pics. .. Looking forward to this for sure..

Any props to you for reading that man.. And guessing you're talking about Andy... He actually responded to me about a question I posted recently about the ms8

Hopefully this works .. You going to add anything else into your system?

skathe

yeah ive read alot in the damn thread on diyma. so much friggin info, biggest trouble i had was setting the right slopes and octave for my speakers to sound good running active. still have some issues with active at high volumes as i get clipping so i run defeated most of the time just for a flat signal going to my speakers and have it adjusted on my passive xovers.

sounds pretty supreme though with my setup, fine tune with the 31 band EQ if i need. have a cpl presets saved that covers most though.

vtec4me21

I have been thinking about taking some pictures, why not if it helps someone else out. I've always had aftermarket systems, but reading and learning more about it all there is so much information out there.

I'm confident in my abilities, but the unknown is if there will be any noise issues. I'll just have to wait and see.

The install list is:
- RAAMmat package #1 with BXT II and Ensolite In the front doors and rear deck for sure along with the trunk and other spots as needed.
- Factory Deck -> Solder in RCA to LF and LR at OEM pre-amp wiring harness + amp remote from wiring harness -> JBL MS-8 -> PPI P900.5.
- Front stage active 2 way: Image Dynamics CTX-6.5cs
- Single sub: Image Dynamics ID12 D4 V.3
- Sub. box: Ground Shaker SQ 1 12-GRAY
- rear speakers: meh...factory for now run off the MS-8. I may or may not upgrade these later.
- Stinger 4 gauge power, distro. blocks, RCA and speaker wire.
- 14 gauge for front stage and 12 gauge for sub.

BTW if anyone needs some quality RCA's you can get Stinger HPM3 cables such as these: http://www.ebay.com/itm/Stinger-HPM3-17ft-2-Channel-RCA-SHI2317-/161182429936?pt=US_Car_Audio_Video_Interconnect_Cables&hash=item258738b2f0
I still need to figure out some caps to protect the tweeters from any unwanted frequencies such as turn on pops. I'm reading and found some conversions for this, but might just ask a local shop and see what they recommend. I would hope they have the caps to sell me.

BlackNsexy2010

Yeah man snap some pics for us.. This is my first build so I'm just learning as I go

read great reviews on the id's and considered them as well.. Got some polks instead.. Planning on doing raam/ ensolite as well.. Just not sure how much we really need with our cars
I just wired 14gauge into one of my doors this weekend... Took awhile but it was also my first time

Okay question..skathe had mentioned using caps to me too.. But the tweeters .. Why would you need a cap when you have the ms8 processing for you ..wouldn't this limit the frequencies going to the tweeters?

vtec4me21

The caps are to protect the tweeters from any full range signals such as a turn on or off "thud". The caps will filter the unwanted signals. Yes, the MS8 should block any unfiltered signal during operation, but this is an extra safeguard when the devices are powering up or down, therefore the MS8 wouldn't protect the tweeters in this case.

I'm sure there are too many variables to tell you if caps are needed or not, and it may not be needed for my install either. It's something else I ran across while learning about active processing. I'll probably just talk with a local audio shop to get there recommendations. From what I've read you can pick a value for the cap that is below the normal crossover point and won't affect the sound much if at all that is noticeable.

I'm using the rammat more for reducing panel vibration and help dampen the door skins as I'm sure the ID mid will expose some rattles. I'll also be using some aluminum flashing and flashing tape to cover up and seal the doors, then lay down some rammat tiles and finally

mercman

I have posted this before, but here goes. The maximum input level for the MS8 is 2.8 volts. The factory HU outputs 4 volts (8 volts differential) with a 0db reference tone. No amount of processing can remove the distortion created this this type of overload. If you want to go with a DSP then find one that can handle the signal level of the HU and that has balanced inputs. I have highlighted the input level of the MS8 in the specs below.
It’s a good idea to use a protection cap on the tweeters.
Jeff

MS8 Audio Specifications
Number of Output Channels
Up to 8
Maximum Input Voltage (Speaker-Level Input)
15V
DSP Time Correction
Yes
Output Connections
8 x line-level; 8 x speaker-level
Signal-to-Noise Ratio
(Line-in>Line-out) 90 (Line-in>Speaker-out) 85
Number of Input Channels
Up to 8
Built-In Amplification
Yes
Electronic Crossover Functions
DSP, up to 8 outputs, 6dB/12dB/18dB/24dB/octave
Seating Position Optimization
Driver, front passenger, front area, rear area
31-Band Graphic Equalizer
Yes
Tone Controls
Bass, Mid, Treble
DSP Equalization
Yes
Maximum Output Voltage (Line Output)
2.8V
Frequency Response
20Hz–20kHz
Input Signal Conditioning
Yes
Maximum Input Voltage (Line Input)
2.8V

BlackNsexy2010

Yeah after posting did some research and found this
http://www.diymobileaudio.com/forum/...eter-caps.html

I'm now going to consider this.. Hope you find some good info ...I'm tired of researching lol.. But I also don't want to ruin my gear

In terms of rattles.. If you have anything in the door pockets you will get rattles..trunk def rattles especially if you have a license plate frame..also ..sunglasses holder..if you have something in it will rattle.. I noticed it has a screw..you may be able to get some mat behind it..I haven't tried it.. I just noticed the ceiling right behind me has a small rattle too.. I'm not going to do anything until it gets warmer though

BlackNsexy2010

Mercman.. I've seen you post about this before.. Okay so what about for us who have already bought and installed the ms8... What can we do? Is there something that lowers the voltage coming from the headunit ?

vtec4me21

In the JBL MS-8 instructions starting on page 25 it says:

skathe

most of the rattling i experienced was where my sunglasses holder is etc. the rattling was primarily coming from garage door opener panel with mic in it. I totally removed this and put dynamat inside this and it severely reduced the rattling (i left this panel removed bc i dont use it and its impossible to make rattle proof unless you use dynamat along the edge of the fitting but it is very ugly)

i also ride around with my sunglass holder down and its rattle free

mercman

I built a customer converter a few months ago that did just that, the design was based on the test converter I used in my post on the base TSX system. So it can be done.

The 2.8 volt limit is a hard number based on the design of the input stage and is not adjustable by the setup program. The speaker level inputs will handle the higher voltage and should be okay with the balanced signals since most speaker outputs are BTL. You won’t have any noise rejection but it won’t clip.

Jeff

niebur3

If they go pre-amp, they should be fine. The problem is most are connecting post amp, which is making the input voltage way too high. No matter what, the voltage isn't constant. It increases as you turn the volume up. Also, you have crossovers set in the amp and then you are setting using the MS8....they have to be all jacked up doing it that way.

If you are going post amp, set the volume on the head unit so that at max, it is below the 2.8 volts. Then use the MS8 to control volume. This will also serve the purpose of properly defeating the factory set eq inside the amplifier as well.

If it was me, I would run the signal going into the amp (from the head unit) right into the MS8 and bypass the factory amp. The MS8 is probably in the trunk and so is the factory amp. The only difference is taking the wires before the amp instead of after and connecting them to the MS8. It should work just fine and it will sound much better.

If you do want to run RCA's straight back, then tap the signal wire at the back of the radio and simply wire to an ARC ALD (accepts balanced inputs) and run an RCA back. The ALD is a line driver that will increase the voltage as well for better noise rejection. Simple as that.

mercman

To those reading this post and trying to make sense out of it or trying to decide if they should buy an MS8 for the TSX I will clarify.

The MS8 is a wonderful piece of technology but it is not a good fit for the TSX. It was designed to improve the sound of factory HUs with speaker level outputs and internal volume dependent EQ. In other words, your basic entry level factory radio, it was not designed to accept balanced signals or line level signals over 2.8 volts. So this eliminates the TSX premium HU and most aftermarket HUs from the list of systems the MS8 is compatible with. If you are looking to go with an EQ of active crossovers then look for a unit dedicated to that and use the money you save on speaker and amp upgrades.

Now, for those that have an MS8 and are trying to make it work, first as I have already pointed out, the max line level input is only 2.8volts. The factory HU outputs 4 volts (8 volts differential) with a 0db reference signal undistorted at full volume. The other issue I have stated before is the TSX HU outputs a balanced signal and you can’t just plug it is to the MS8 without converting the output to unbalanced. So, if you have an MS8 and don’t want to sell it on Ebay then I would suggest using the signal post factory amp and setting the MS8 to sum just the front door and tweeter signals. Use the sub signal for the sub.

As far as the other suggestions:
Connect the MS8 directly to the TSX HU, you can’t do this due to the signal level and the balanced input requirement. You’ll get a boat load of distortion and have zero noise rejection, very bad idea.
Using a line driver with balanced inputs and running RCAs back to the trunk. You will lose the noise protection of the balance line; think about it, the engineers that designed the car and audio system went with a balanced setup because of noise in the car. Do you think they would have done this if it wasn’t required? The other issue is, so now you have the line driver and $100 set of super-duper zipomax ION depleted supper linear RCA cables. The line driver jacks the HU output up to 10 volts to try to overcome the noise that the RCA cables will pick up on the way to the trunk. Now you have a 10 volt signal with a 2.8 volt input limit, you just made things a lot worse and are out a few hundred dollars.

Lastly, to get the best sound quality out of any system the signal levels must be understood and carefully matched. You cannot get this by adding endless drivers and having to pad the signal down and raise it up every step of the way. You must start with a known value, hence the 0db reference tone and work your way down the signal path to the amp.
My ultimate suggestion for TSX audio upgrades is to start with speakers that you like the sound of without adjusting the tone controls or EQ. Then power them with a good amp that has balanced inputs, without this quality foundation your sound system will never live up to its potential no matter how much tech you throw at it.

For those who are new and do not know me. I have over 40 years of electronics experience right down to the component level. I service and repair pro audio and HiFi amps. I have had a gen 1 TSX that I designed the mercman cable for and an active balanced line converter. For the Gen2 ELS system I designed a digitally controlled analog preamp to replace the POS ELS digital amp. I have also had the opportunity to test and measure the 2nd gen base system. Lastly, I have been modifying car audio since the days of FM converters, 8 track decks and CB radios.
Jeff

BlackNsexy2010

It's great to see some of the top audio guys here posting on this...I went post amp because I couldn't figure out how to go preamp.. Now it seems you guys are both saying to do two different things.. I personally don't hear any noise ..or maybe it's my novice ears..but if u had an ms8 installed in your tsx.. What tests would you maybe run using what equipment to figure out the best setup.. I'd be open to try n run some tests.. Or even meetup with some people

vtec4me21

Thanks for all the consolidated info. on the TSX factory signal from the HU. I've read bits and pieces everywhere but it's good to have it all in one spot.

Options are:
- Keep the MS-8 and use the after amp front / sub. channels.
- Return the MS-8 as it hasn't been installed and choose another DSP.
- Another option would be to ditch the factory HU and use a Pioneer DEH-80PRS for running an active setup plus an auto tune option. This would require a steering wheel adapter and other adapters to be purchased to keep the factory options.

I chose the MS-8 as it would basically tune without having to use an RTA and mic. or having to know all about manually tuning a DSP.

It doesn't sound like any option is a clear winner as each has drawbacks.

BlackNsexy2010

Okay so this may not change anything and I may be missing something but.. Per the info we've so far talked about.. The 2.8 volts is an issue..however ..and I may be missing something..but per this which I will post below .. Max input per line level is 2.8 however speaker level is 15 .. Go the middle of the link below and hit products and specs

http://www.jbl.com/estore/jbl/us/pro...-8/MS-8_JBL_US

Also..in this article... See the first post on page 23 ..Andy from jbl the main face of this product said the 4v should be no issue because of the way you set it up

http://www.audiogroupforum.com/csfor...=65668&page=23

niebur3

MERCMAN, as someone who also had 20+ years of audio experience and has experience installing a MS8 and doing so with an aftermarket AND factory head units, the info above is not entirely correct and I gave my info in red throughout your post.

For anyone wanting more accurate information about the MS8, read this:
http://www.diymobileaudio.com/forum/...ml#post1073797

mercman

If get some time I will post the photo I took from my O’scope of the peak to peak waveform. In the meantime, take a look at this post
https://acurazine.com/forums/2g-tsx-audio-bluetooth-electronics-navigation-304/my-els-audio-upgrade-els-preamp-819501/

See, I really do know electronics and the TSX audio systems. If I didn't would I have been able to build a replacement for the ELS amp? I have lots of other posts on the 2nd gen base system including some about the active balanced converter I built. If I didn’t know what the signal level of the HU was I would not have been successful at designing either one of them. Oh, if you notice the signal level from the ELS HU is 5V P-P differential; this signal drives the A/D converters in the front end of the ELS digital amp.

Lastly, The TSX base system starting with the 1st gens is completely different then any previous Honda system, so saying that you installed something on and old RL and expecting the TSX to be the same just doesn't cut it. I’m not a car stereo installer; I have a real electronics background and can actually design and repair all sorts of circuits.

It’s funny, when I got my 1st gen TSX and decided to upgrade I did some looking at the posts and realized nobody had did a truly successful amp install. I broke out my scope and did some testing and measuring of the HU signal with a test CD. I discovered that the 1st gen was differential, that the HU was clean and flat; I measured the output impedance of the HU and checked the amp output on my test bench. I posted my findings and the resident experts gave me all sort of guff about it. Time and noise free installs have proven that I was right and I am right about the 2nd gen TSX as well.

I have nothing to sell, I don’t work at a car audio store and I have no brands that I push here. I just really do know electronics and consider myself an audiophile. At home I have both tube and solid state audio amps and can tell the difference in each. When I build a car system I go the cleanest sound by avoiding excessive D/A and A/D conversions and processing. I also don’t piss my money away on fancy cables; using a so called balanced RCA cable with an unbalanced signal is just silly.

I will say it again; the MS8 is a fine unit but not a good fit for the TSX system. I would put it in my Subaru to improve the factory HU but never in the TSX. Oh, and yes, I could build and adapter that will not only convert the HU output to balanced but also drop the signal for the MS8 line inputs but I wouldn’t be installing the MS8 in the TSX anyway.

Lastly, I think it’s a bit of a kludge to have to use the volume control on the DSP instead on the HUs control. Aren't there enough distractions while driving, watching DVDs and texting without having to reach for the remote to turn up the radio?
There are better solutions for the TSX.
Jeff

niebur3

I only questioned your measurement of the output voltage of the factory Head Unit. I never said you didn't understand electronics. Just because you can make something to replace the els amp, doesn't make you an expert on all things car audio, including the MS8. A little defensive?

FWIW, I will report back more info as my install progresses and if I am wrong with anything I have posted, I will be the first to say so. With that said, I am a dealer/enthusiast but I don't sell the MS8. In fact, personally, I can't stand the MS8, but my reasons are about using with a high-end system and some of the limitations it has VS what has been talked about here. I might be wrong, but I don't believe you have ever installed or even touched one AND many of your points on why it is bad was just plain inaccurate.

I'm not sure at all what you even mean by:

"When I build a car system I go the cleanest sound by avoiding excessive D/A and A/D conversions and processing. I also don’t piss my money away on fancy cables; using a so called balanced RCA cable with an unbalanced signal is just silly"

The fancy cable comment is coming from where? The $10 RCA's I suggested? In what way is a RCA balanced? I can somewhat see the D/A and A/D comment, but it is pretty much irrelevant in this conversation. AND processing in a car environment is an absolute MUST to get the best possible sound.....there are no ifs ands or buts about this point. A car is a terrible environment for audio and processing (and proper installation) is the only hope of taming at least some of it to get decent sound.

I have built many systems in various cars with differential HU's with no special anything needed. I have competed in sound quality competitions for years, placing at world finals in USACi and published 2 different speaker test, testing the world best drivers.

I'm not here for a dick measuring contest and there are usually multiple ways of getting the job done. I am just giving an alternate way. I do realize the work and info you have done, especially with your plug/play adapter and in no way and I trying to discredit you or your knowledge overall, just giving more info and sharing my knowledge.

mercman

I’m not looking for a pissing contest either, if you want or need to use a DSP to tailor your sound then go right ahead. I don’t do sound competitions so I can’t speak to what is required to win. My systems are strictly High Fidelity where the goal is not to add anything or take anything away from the original material. Basically, a wire with gain, in order to do this THD and IM must be kept to a minimum and dynamic range must be at maximum. The aim is to deliver a signal to the speaker that is only bigger in amplitude when compared to the original.
While I don’t use them, a DSP can compensate for poor speakers and room acoustics as the case with the TSX ELS system, it actually made the .50cent factory speakers sound OK. The problem was that when power and better speakers were added the whole system sounded like crap. My preamp fixed this by removing the digital amp and DSP and replacing it with analog tone and volume/fade controls. The preamp was designed for minimum THD and IM and max dynamic range. I had to pay careful attention to signal levels thought out the system to achieve this.

So, getting back to the subject, if you feed your DSP a good clean (HiFi) signal you will get better results than if you just blindly connect it up and press the auto fix button.

My original points still stand based on sound electronic design principles.
Taking a balanced line and terminating it into a non-balanced load will degrade the signal. It might work but it’s not right and not 100%. Balance to balance is the way to keep noise and distortion at bay.
The HU output is too hot for the MS8 line in’s and some sort of padding is needed. Doing it this way will allow you to use the HU volume and since the output response curve doesn’t change with volume setting like the HUs the MS8 was designed for the MS8 can be set once and that’s all.

Running coax to the HU is not a good idea, that’s why the OEM system was designed for balance signal lines.

Giving the MS8 a clean signal with a wide dynamic range will give you an edge over competitors that don’t know how to do this.

The DSP is desired should always be the last piece of a system.

Jeff

vtec4me21

I finished the MS-8 install and I'm very impressed so far. Granted the speakers may need time to break in and I'm sure some fine tuning is in order with the MS-8 but here are my findings.

- Using the FL and FR pre-amp signal from the factory HU is possible and can be connected to the MS-8 with an RCA cable. In my case this did not introduce any noise. I used a set of Monster Cable RCA's and cut off one end of both the L and R cables. This was soldered into the FL and FR pre-amp channels at the factory amp location.

- In my case I have zero noise either with or without the engine on. The only noise I can detect is a faint pop during turn on and the normal faint hiss with the volume down all the way.

- During the MS-8 setup, I found that a volume of 32 from the head unit was the correct spot where the signal was not to faint and not clipping per the setup program. I used the MS-8 volume of -30 during the acoustic setup and -6 during normal listening. Volume is controlled by the head unit and is normally in the 20's range.

- An active setup is very impressive, and I can see why people just ditch the rear speakers. The rear fill would be a waste IMO. If you have the capability to run active without a component set passive crossover I highly suggest it. With the MS-8 it is very distinctive that the stage is now pulled in front of me, I can pick out instruments and closing my eyes I can imagine a concert in front of me. I'm toying with the idea of installing a center channel speaker just to see how it sounds instead of the MS-8 phantom center.

- Are there other superior DSP's on the market? Sure, but that isn't what I was after. I wanted a solid DSP that had an auto tune capability like some of the Pioneer head units and that is exactly what I got. I didn't want to invest the extra time or money to manually tune for days on end.

The install list is:
- RAAMmat package #1 with BXT II and Ensolite In the front doors and a bit on the trunk floor for now. I'll work on other spots as needed.
- Factory Deck -> Solder in RCA to LF and LR at OEM pre-amp wiring harness + amp remote from wiring harness -> JBL MS-8 -> Alpine PDX-V9.
- Front stage active 2 way: Hertz ESK F165.5
- Single sub: Image Dynamics ID12 D4 V.3
- Sub. box: Ground Shaker SQ 1 12-GRAY
- Amp: Alpine PDX-V9
- rear speakers: removed.
- Stinger 4 gauge power, distro. blocks, RCA's and speaker wire.
- 14 gauge speaker wire for the sub and factory wiring for the highs / mids.

hokusai

Can the MS8 be wired before the factor amplifiers? Or, does the MS8 have to be wired after the factory amplifier?

BlackNsexy2010

U can do either .. Most here did after .. But few have it before.. Before would be ideal..just requires more knowledge

hokusai

Please disregard my last post. I see that the MS8 can be connected at the factory preamp level or after the factory amp.

Can someone please explain why you only need to connect a left and right RCA cable to the Front-Left and Front-Right pre-amp signal from the factory head unit?

Is this because the front left and front right signals from the head unit or pre-amp carry the full range of frequencies (i.e., unprocessed or unfiltered by the factory amp), including subwoofer frequencies, and thus, no other inputs are needed beside these two to run the MS8 or Rockford Fosgate 3sixty.3?

From what I have gathered, it appears the Head unit sends out only two channels (i.e., FL and FR), not eight. It seems that these two channels from the Head unit are processed by the factory amplifier into eight channels (i.e., ELS or tech version).

If I connect the MS8, or another signal processor, after the factory amplifier, would I have to use more than the FL and FR channels? Is there an advantage to using all 8 channels post factory amplifier to connect into the MS8 versus connecting only the FL and FR channels to the MS8 at the preamp level?

Lastly, if you connect the MS8 at the factory preamp level, would you still be able to adjust the bass, treble, fader, balance, center, sub, SVC, and Dolby through the head unit (these are the system controls on the factory head unit). Or is the ability to adjust these controls from the head unit non-existent after connecting the MS8 at the preamp level? If so, is this also true for connecting the MS8 at the postamp level? That is, once the MS8 is added, is all of the equalizer tuning (e.g., bass, treble, SVC), and front and rear fading, left and right balance, and Dolby digital handled by the MS8 and not the factory head unit?

boostdashcancel

I thought it was explained pretty straight forward here:

Vtec4me21 said:

About the HU line level outputs: The audio lines out of the Accord HU are a “balanced pair” or “differential output”. This means that there are 3 wires per audio line – signal (+), signal (-), and shield ground. Neither of these 2 “signal” wires should ever directly be connected to a common ground – this can (at best) cause excessive noise or (at worst) cause a HU output overload & failure. So, the balanced audio line needs to be, 1) connected to a 3 wire balanced input device, or 2) the 3-wire line needs to be adapted to a “single ended” common ground 2-wire signal (usually done with an isolation transformer). Fortunately, the MS8 RCA inputs are “quasi balanced” and isolated (not common grounded) and they can be used directly from the HU with a special wiring consideration.

The RCA's in this context are balanced so each RCA has 3 wires or 3 signals (+, -, shield gnd) to send out. FL/FR audio lines are the main send/output signals from the HU. Oh, and the MS-8 says you can use RCa's so vetc4me21 is making a point to follow a thought pattern consistent with the eom design which utilizes balanced signals from end to end.

In other words, the goal is a balanced signal that bypasses the factory amp and goes straight into the MS-8.

hokusai

Vtec said:
- During the MS-8 setup, I found that a volume of 32 from the head unit was the correct spot where the signal was not to faint and not clipping per the setup program. I used the MS-8 volume of -30 during the acoustic setup and -6 during normal listening. Volume is controlled by the head unit and is normally in the 20's range.

Hokusai reply:
So it sounds like you can control the stereo system volume through the ELS head unit if you connect the MS8 at the preamp level. However, I thought someone mentioned that the volume would not be able to be adjusted at the ELS head unit if the MS8 was connected at the pre-amp line level. From Vtec's post, it looks like volume can be controlled from the ELS head unit. Vtec or anyone else who has connected the MS8 or any other DSP at the preamp level, can you please verify that the volume can be controlled via the stock head unit once the FL and FR signal from the head unit at the preamp level is connected to the MS8 or another DSP?

vtec4me21

Yes, with the products I installed the factory head unit controls the volume. That's because the MS8 volume is set quite high. I have heard of people doing the opposite, but why try to fool around with the MS8 volume all the time.

You have an ELS factory setup, so that is a difference. I'm not 100% sure if this would work for you, meaning you would possibly need an aftermarket deck as well. The ELS head unit may do some processing on it's own (Dolby) as you mentioned in an earlier post in this thread.

I don't know if this setup would work with a different DSP, that would require further research.

I can tell you that my install is still working great, and I enjoy it every day. I have no regrets in the products I chose and the methods for the installation.

hokusai

Vtec, I am glad your set up works. I looked at the wiring diagram for the tech and non-tech versions and it appears that there are two more wires on the tech version that are not on the non-tech version, those being what appear to be labeled "EL 8 Data+ (positive) and EL 8 Data- (negative)" wires that are shielded. I do not know what these wires do, but they do not seem to be on the non-tech version (i.e., at the preamp level).

On another note, can you tell me where you bought your wiring harness for the stock head unit?

vtec4me21

Correct, the non-tech package is what my car has installed. I don't know what the EL 8 Data wires are for.

I did not buy a wiring harness for the head unit. Any wiring was done at the factory amp location. Grabbed the front L / R input signal, soldered in an RCA cable and connected that to the MS8. All output wiring from the aftermarket amp was soldered into the factory amp. output wiring back to the factory locations.

Here's my install thread:
https://acurazine.com/forums/2g-tsx-audio-bluetooth-electronics-navigation-304/vtec4me21-2011-tsx-non-navi-sound-system-install-log-904804/

Qmg

Hi, if you're still out there, I'm looking through all the info here, I am very confused. I'd like to upgrade speakers and amp in my 2009 tsx with Navi.
What are the best ways to go about this using oem head unit?