New to the forum - just drove a sweet new 2011 Accord SE off the lot and I'm dying to get some upgraded audio in it!! I'm mostly new to car audio and have been scouring the net for info the past week; I keep finding myself back here though due to the great information provided by all and particularly the informative posts by keep_hope_alive!

I'm considering something akin to the basic budget system for around $500 sticky. Particularly, I'm open to anything that doesn't alter the stock headunit and is budget friendly (up to $1000 or so) and am more concerned with SQ than waking up the neighbors. Here's some questions I haven't been able to figure out:

1) What is the importance/role of the rear speakers? My first inclination is to replace all of the existing speakers (all 6.5", front component, rear coaxial), but I'm seeing where some people say to just leave the rear speakers powered off the head unit, some say to remove them all together, and some replace and power off the amp. Is this a point of personal preference or based on budget maybe? Is it better just to save that money and spend it on better components elsewhere?

2) If sticking with the stock head unit do I need to add a Processing unit? Something like the JBL MS-8? Or is this only needed for certain headunits? What is the benefits of adding this to what I currently have? Is the only con the price?

You guys are awesome! Thanks in advance for the help!

 

answers are in red. the budget is great and very helpful. what is it you want. do you want a sub or do you just want to increase the sound quality. do you want to replace the speakers and amp them or do you want to run them off of the headunit. amping will require some wiring work. the stock wiring in a honda is not sufficient for much more power than is already run through it, so if you were to amp the speakers it would require some wiring.

along with your budget on price what is your budget with your time and effort you are willing to put into upgrading the system?

 

Thanks for the response! My goal? Well about 10 years ago or so I had a friend that sold me for super cheap a nice system for the old Civic and I absolutely loved it. That was 6.5s in the doors, 4.25s in the back, 1" tweeters, 10" sub, 4 channel 400 watt RF amp, and a head unit. Pioneer I think. It had some swimming dolphins graphics and was state of the art. haha. That car got totaled several years back. With a kid on the way, I'm feeling old and need a reprise on my youth! j/k. I'm looking for crisp high end and tight bass. Think rocking out to some Rage Against The Machine. I would agree with you on wanting to feel "in the middle" of the sound.

I know I got 6.5s all around. The front has components with the tweeters in upper corner of the door. So you're saying I need to have some type of enclosure if I keep the rear speakers? Should the rear speakers be of a different type that the fronts? Send them different frequencies? Will I need two amps for my proposed 5 speaker setup or would you recommend to use a 5 channel amp?

Due to Honda's stock wiring, you're saying I definitely need to make the "big 3" upgrade? Even if I'm only going with a 400 watt amp?

I'm a DIY person by heart and engineer (civil) by trade. I'm definitely up to undertake the challenge. Wiring the amp won't be a problem. Good thing I has internetz!

What would you do if you had my car and $1000 to upgrade the audio? Only rule is you have to keep the dash stock.

 

i didnt have time to read the whole post but not a big 3 upgrade just run new speaker wire.

 

I will respond in detail later tonight after I work on a 4-cycle engine...

 

ok, the mower is reassembled.

honestly, this topic could be it's own sticky (and I may rearrange later).

You have a new car, you want to upgrade the sound system, where to start?

First step is to identify your priorities. What don't you like about the stock system and what are your goals. If you don't like how the stock speakers sound, start with the speakers. Many people jump to adding subs thinking it will give them better sound, but bass makes up about 2% of what you hear, and it should receive no more than 10% of your attention if SQ is your goal. The front speakers are the most important drivers in the system. How they are powered is equally important.

You can reference my sound deadening and speaker install sticky - to see how much time, money, and effort I put into front speakers. Not just on the installation of the speaker, but also on the treatment of the speaker cavity (i.e. doors). The difference between a speaker in a stock door and a speaker in a deadened and sealed door is staggering. you'd swear it was a different speaker + sub. the enemy is phase interference/cancellation. those large holes in the door result in cancellation of low frequencies unless careful consideration is given to seals. we notice that the stock system usually has surprising amounts of midbass, given the cheap drivers. that is because those speakers are well sealed and optimized for that location. yes, acousticians design those systems. sadly, there is very little money put into them. the speakers are worth $1, probably less.

So I start with not only upgrading the front speakers, but also the amp for them. Don't expect much of a gain to be had using the factory amp.

I also invest as much as I can on front speakers. If I had a new car, and $1000 to spend, i'd spend it on the following:
1. component speakers ($350-$500)
2. 4 channel amplifier ($300-$400)
3. sound deadening (40 square feet = $100)
4. wiring (~$100-$200)

I would also consider buying a used amplifier so i could get more for my money. Sometimes I will consider used speakers, depending on the seller. That said, I also like warranties.

Now, I've also done entire systems for $1000. One recent system was the following:
Hybrid Audio Technologies - Imagine I61-2
Alpine MRP-F300
Hertz Audio ES-250
This went into a 1939 Chevy Coupe - custom show car I did. The result was darn good, but this was a small vehicle.


next onto rear speakers...

 

Rear speakers is a hotly debated topic. As Neo mentioned above, there are several things to consider.

When I listen to music at a concert or in a room I have speakers in front of me. I stand facing the speakers. Our ears are designed to be most effective when sound is in front of us. When we are in a room or concert, we also hear reflections from behind us. Those reflections give us the effect of being in that space, and how long or far apart the reflections are give us an indication of the size of the space. acoustics 101.

In a car, the space is confined and the sound dies out quickly. without rear speakers, we tend to sense the emptiness behind us. but we want to be careful how we go about adding rear speakers.
Rule #1: no highs, no tweeters. even in a room, high frequencies are usually the first to decay or be absorbed. we don't like high frequencies coming back at us, we like them direct only. this also helps us in developing a sound stage - highs behind us hurt the sound stage.
Rule #2: they should be tonally similar to the front speakers. we don't want the rears to sound drastically different than the front.
Rule #3: they should not distort - prevent distortion from having too small of an amp or distortion from subwoofer pressurization (i.e. rear deck speakers with trunk subs).
Rule #4: they should be reduced in level such that you don't readily identify they are even on, but you instantly know when they are turned off. that gives us the "ambiance" we are looking for.
Optional #1: try to filter them (bandpass) between about 400Hz and about 4kHz.
Optional #2: try to delay them, more than 10 milliseconds - how much depends on the volume of the vehicle and tuning capability. some try to get to 20 milliseconds, some even more.
Optional #3: try to give them an L-R mix (meaning the amp combines the Left out of phase with the Right. The result is the rear speakers having no information that is common to Left and Right as that information is what gives us a center image. L-R rear fill mixing done right can strengthen the sound stage.


What we don't want with rear speakers is to do what we all did in the 80's and into the 90's - putting most of the power/sound behind us. I was guilty of that as well. Once you focus on the front playing the widest range possible, you find that you more accurately reproduce music, and you enjoy the experience more. I've gone from everything behind me to nothing behind me to a strong front stage with rear fill. I'm the happiest now, but I have my rears filtered, delayed, and eq'd.

 

Subwoofers are almost as difficult as front speakers, but for different reasons.

subs create so much pressure that they vibrate the car and make all sorts of things buzz and rattle. This is annoying and no one is impressed. keeping the car quiet is tricky and usually requires adding a lot of foam between panels. not that expensive, but very time consuming.

subs also operate in the frequency range where the wavelengths are on the order of feet. a 40Hz tone has a wavelength of 28.25 feet. a 80Hz tone has a wavelength of 14.125 feet. these long wavelengths are subject to cancellation if we don't carefully locate them in a vehicle. we want to avoid placing a subwoofer 1/4 wavelength from the rear of the trunk. the reason is that we get cancellation since sound will bounce off the rear of the trunk and come back, combining with the original signal. when we are 1/4 wavelength away, our bounce then arrival is now delayed by 1/2 wavelength = cancellation. if you can ensure that the subwoofer cone is less than 1/4 wavelength away from the rear of the trunk, at the highest frequency you want the sub to play, then you are usually in the clear. note; however, that even if you don't have pure cancellation, you certainly have partial cancellation.

this is why the rear corner of a vehicle usually offers the best performance. an alternate location is behind the rear seats but walled off and sealed 100%. that way the trunk is no longer a factor. simply placing a box in a trunk behind the rear seats offers the least enjoyable bass experience (when SQ is the goal). additionally, the rear corner sub location allows for maximum retention of trunk space (when fiberglassed into the corner to optimize airspace).

choosing the right sub and sub amp can be quite tricky. i believe you should always spend more on your front speakers then sub, but good subs are more expensive to build due to size. additionally, you need more power to drive the sub, so amplifier costs can go up. but if you care about accurate reproduction of music, you need to balance the speaker output with the sub output.

for most people, one nice 10" sub properly corner loaded with about 500W RMS of clean power is plenty (and can usually sound better than the standard dual 12" install in a box behind the rear seat). This single ID 10" in a Scion xB was more than enough, tons of output thanks to a proper ported enclosure and proper loading off the rear hatch:
http://forum.sounddomain.com/ubbthre...page/3/fpart/1
That install also covers front components and tweeters in the sail panels, without sound deadening. Deadening will be added later by the owner.

 

Another expense with integration into a factory system is the actual integration. You usually want to get some sort of OEM processor, like the JBL MS-8. Alpine, Pioneer, MTX, Audio Control, JL Audio, Rockford Fosgate, etc. all make OEM integration products.

There are two things you want to do when integrating with OEM
#1: eliminate the factory EQ. some factory systems have an EQ that compensates for their speakers, and sometimes the compensation depends on volume. when we upgrade speakers and amps, we don't want that EQ anymore. some integration pieces will play a calibration sweep through the factory system (via CD) and correct for the EQ. this usually means you abandon the factory volume **** and control the volume through a separate ****. you may or may not like this, but the sound quality is usually greatly improved.
#2: amplifier control. we gain a turn-on signal for the amps, and we get more EQ, crossover, time delay, etc. for each amp in order to achieve better SQ. usually, just having Bass and Treble on the head unit is not enough to get a great sounding system - especially if you haven't invested a lot of time and effort into treating the vehicle.

I run an 8-channel processor (Alpine PXA-H701) because I want control over each speaker at my fingertips. It has helped me tune a fabulous sounding system. I would consider an Audison BitOne or JBL MS-8 as a replacement, or even the new Alpine PXA-H800. These processors aren't cheap, and once you add them, you're also adding new amplifiers for all of the speakers. So the budget quickly climbs to $2k or higher.

Cheap integration can be had if you get amplifiers with high level inputs and an auto turn-on feature (so you don't need a wired remote turn-on lead). as long as you don't have a premium sound system with a separate amp, high level inputs can be enough.

If I am simply adding a sub, I like to get my signal from the front speaker outputs so i can use my fader to turn down the factory rear speakers (when retained). when factory rear speakers are removed (from the rear deck), I will use the unused rear speaker signals to feed the sub amp high level inputs.

For amplifiers without high level inputs, an external Line Output Converter (LOC) can be used. Some LOC's will generate a remote turn-on for you.

 

Wiring is always important. I like to upgrade wiring whenever possible. This includes grounding, power, and speaker wire.

The Big 3 is important whenever any sound system/amplifier is added. Regardless of power, it is still an increased load on the system. Factory grounding is usually quite poor, especially the engine block to chassis bonding jumper. At a minimum, i'll upgrade grounds. the factory power wire is usually sufficient for it's output. Upgrading that wire just reduces voltage drop.

The battery to chassis and engine block to chassis ground wire upgrades are a must for any system. Hell, I did it on my wife's Camry when I added a new head unit. Granted, I plan on adding a small amp someday.

When sizing power wire, think about the future and keep distance in mind. Where you put the amp and how you route the wire will determine the desired length. As length increases, so does voltage drop. Increasing wire AWG is how you decrease voltage drop. I typically use 4 AWG minimum when my power wire is longer than 12 feet. I'll jump to 1/0 when I expect >1000W RMS to be available.

Amplifier grounds are equally important, and the location of the ground is crucial.

Grounds should be to bare metal on the frame or floor of the vehicle. Battery and engine block grounds are usually to the frame. Amplifier grounds are usually to the floor. I never use existing bolts for grounds (i.e. seat belts, suspension, brackets, etc.) unless that was their OEM purpose. The only bolts i'll reuse for ground are the factory battery/engine block grounds. Amplifier grounds are always new. Locate a spot on the floor, as close to the amp ground terminal as possible (no more than 12"), that is accessible from both sides. Triple-check clearance and drill a hole sized for the ground wire ring terminal hole. mask off an area around the ring terminal size with tape and sand the spot down to shiny metal. run a bolt and nut through the hole and ring terminal and tighten. use washers where necessary but not between the ring terminal and metal. finally, seal the bottom/exterior side with silicone. I typically keep the nut and threads on the inside of the vehicle.