5/20/08 UPDATE: I now have pictures for most everything. I have smaller pictures for easy initial viewing, but are not so great for seeing specifics, but also included are large pictures with notes. Due to the number of pictures and size of some of them I have just made up a quick webpage explaining most everything along with the photos. The link is here:

Stereo Upgrade Info With Photos
if the link doesnt work, use this address:
http://www.blakbyrd.com/Car/index.html

Everything below is the same ole original post: :)

Over the past month or so I have been working on doing a complete stereo system upgrade, and have been doing some online research of what will fit where in an 850. As such I have come across alot of conflicting information, from what head units will fit, to what speaker sizes to use in place of the OEM speakers, etc. I have also come across quite a few site with posts from people asking these questions (some getting good responses, others bad, and some just plain confusing).

So, I figured I would add a little more comprehensive post here, regarding what I have found to work, as well a to give the specifics of what I used and what was necessary to make it all work.

Below are some specifics on what will fit where in an 850 wagon (mine is a 1995 turbo model). I have read that some of the wiring (for the head unit) is different on a 1993 model, so I am not going to initially mention actual wiring or wiring colors, etc, because this may cause some confusion and possible improper wiring (the diagram I did find for a 1995 was entirely backwards from what they said but all was correct color wise at least). I will mention some specifics on speaker and wiring specifications at the end, which you should keep in mine when replacing the OEM ones.

Head Unit: My stock stereo wa a double din unit (4" tall), and had plenty of depth behind it to mount any standard double din unit into it with little problem. As such I purchased a Kenwood DDX-7019 double din 7" touch screen unit (DVD player, with navigation capabilities, TV tuner, Ipod, etc). It's mounting size and depth was nearly identical to the OEM stereo that was in mine. However, mounting a factory double din unit does require some slight modification to the head unit hole. The factory stereo used a set of rails in the hole to mount to. These rails did not allow the Kenwood mounting bracket to be inerted. The entire hole is comprised of plastic walls and rails, so removing the rails consisted of simply using a die grinder with a small cutoff wheel to cut the rails out (took less than 2-3 minutes to do). After doing so, the Kenwood mounting cage slid in perfectly, but there was no real location of fastening the cage in place.Due to how the cage for the Kenwood was designed I was able to use 2 self taping screws in the bottom of the cage by drilling two small holes in the cage and useing the two screws in the bottom of the cage, through the plastic beneath it (the screws stick through the bottom but do not get in the way of ash tray, so they are completely hidden). To keep thetop of the cage from moving I cut two small notches in the upper part of the hole to use with the folind tabs of the mounting cage (have to be careful here a the upper part of the stereo hol is actually the bottom of the climate control box). From there it was just a matter of wiring and sliding the head unit in place. The mall platic bezel that came with the head unit fit perfectly and looks good to finish off the head unit install (no modifications were necesary to bezel).
Note: For those who have an OEM amplifier, it is usually mounted behind the head unit, which can limit your space behind the radio.Many nice double din units have alot of wires coming out the back (as mine did) and this may make it more difficult to stuff all those wires behind the head unit easily. ANother note, Crutchfield lists that an 850 Volvo cannot fit a double din unit, this is false if you remove the plastic rails, once removed a double din fits perfectly.

Dash Speakers: The dash speakers are small. My OEM speakers were made into a special plastic bracket for mounting in the dash, and were held in place by those annoying plastic puch lock style holders. Removing them wa an easy task. A small flat screw driver will pop them out and then the speakers lift right out. I replaced mine with a pair of Infinity Reference 3022cf 3-1/2" 2 way speakers. These are far better than the crappy one way paper cone speakers that Volvo used (mine were beginning to deteriorate and just touching them caused them to crack). The Infinity 3-1/2" speakers fit perfectly fine without any modifications. However the mounting holes did not line up with the new speakers. Because Volvo used the platic push lock style fasteners, they mounted in the vinyl/plastic part of the dah and there is no metal mounting solution. The Infinities came with mounting screws and the metal clips to put over the hole to mount with, which turned out to work just fine, although I could only mount them with one screw (because of the small speakers, only one screw was needed and they are held in place just fine, and have given no ound of coming loose or rattling). Mounting depth is not all hat important as there is plenty of room below the dash for speakers in this location. The height of the speaker is more important. Anything much higher than tweeter on a pair of 3022cf speakers may come in contact with the factory grills. However they did not interfere with mine and my factory grills are back in place.

Front Door Speakers: My OEM front door speakers were cruddy one way paper cone speakers. Again they were showing signs of deteriorating. Although they are a metric size, they are nearly identical to a 5-1/4" speaker. So I replaced mine with a pair of Infinity Kappa 52.7i 2 way 5-1/4" speakers, which have adjustable tweeters to better aim the sound from them. The Infinities dropped right into the original loaction without any modifications needed. Of course not all the mounting holes lined up, but any two opposing mounting holes did, so I mounted mine with only 2 screws (using the original screws that Volvo used), choosing two 180 degrees from each other. This held the peaker firmly in place and the other 2 were not necesary. The Infinities I used also came with a small plastic box that house the crossover. I found no need to try to mount this as I was able to simply stuff it down below the speaker hole and it lodged in place easily, out of the way, and does not show any signs of being loose or rattling. Mounting depth was of no issue, but again, using any speakers that may have a height taller than the52.7i's might come in contact with the OEm speaker grill (mine fit fine and the original grill is back in place).
Note: Crutchfield says that only 4" speakers will fit in the front doors. This is false. 5-1/4" speakers fit almost perfectly without modification. trying to use 4" speakers will require modification and or purchasing extra mounting hardware to get them to mount in the larger hole. Using 4" speakers will require more work and probably cost more for extra parts, not to mention you have a much smaller set of choices in 4" speakers than you will with 5-1/4".

Rear Door Speakers: Volvo uses a pair of 2-way paper cone speakers in the rear doors, which are just a tad bit larger than the ones in the front door. I replaced these with another set of Infinity 52.7i 2-way speakers.These did not fit as well as the front door replacements did, and there is an added complication to the back doors (easy to work with though).Volvo glues these speakers inside a plastic housing, which most likely helps them to produce better bass. Because the OEM speakers are slightly larger, 5-1/4" speakers do not directly fit with the existing mounting holes as the front speakers did. Some modifications were necessary here. You have to pry the speaker out of the platic houing (be careful not to break the housing trying to do this (use of thi platic housing is not necessary, but it will help to produce better bass with your speakers if you use them). The modifications I had to do are as follows:
- I had to drill two 1/2" holes inot the housing, where Volvo originally just had two small slits to hook up the OEM speakers, in order for me to feed the wires to my new Infinities (you may only need one hole if your speaker choice only has one set of wires to them).
- I had to locate and drill 4 holes in the plastic housing to mount the new 5-1/4" speakers. It is easy to drill since it is just plastic.
- I fed the speaker wires into the plastic housing and then mounted the plastic hoising back into the door with the 4 original volvo screws. I then drilled 4 holes, through the 4 I drilled above in the housing, so that I could then mount my new speakers.You will be drilling through plastic here again, so it is easy to do. I then hooked up the speaker wires and mounted the speaker with the screws that came with the speaker (these are self tapping machine screws, so they go into the plastic with ease, just make ure you drill the holes smaller than the screws).
Again, the mounting depth was of no issue, but the height almot came in contact with the speaker grill, but the original speaker grills are in place and look proper. What I didnt mention was the small crossover box. Before I mounted the plastic hoising in place, I pushed the crossover box inside the door towards the hinge and they lodged in place perfectly without any need to mount them.
NOTE: Crutchfield again say that 4" speakers is all that will fit in this location, and this is entirely false. 4" speakers will require special mountingand possible modifications or extra hardware.5-1/4" speakers fit well here. I have seen where some people have also been able to mount 6-1/2" speakers, but this requires a little more work and the original speaker grills will not fit over them.

Rear Pillar Speakers (note on sedans also): In a wagon, there are speakers in the rear pillars by the lift gate. These are spall speakers similar to what is in the dash, but are in special plastic mountin brackets. You can fit 3-1/2" speakers here, but it will require making special mounts for them (I have not replaced these yet, instead I simply disconnected them...see the wiring info further down for the reason for this). In a sedan, you have what resembles a metric version of a 6x9 speaker, although a 6x9 is reported not to fit without modification, intead a 5x7 is suggested for the easiest replacement, or making a special bracket to house 5-1/4" speakers.

Extra additions: Beyond normal speaker replacement, I also added a self powered Infinity Basslink 10" subwoofer. For what I want, this this is perfect. It sounds great, has plenty of bass and take up very little room. I mounted mine on the left side of the rear cargo area, which fits perfectly between the rear wheel well and the pillar, and still allow me full use of the folding 3rd how seat in the back. Wiring it was simple, with a 10 gauge fused wire from the battery to the subwoofer. I fed the wire through the fise box to get through the firewall, then fed it along the left edge of the car under the carpet to reach the back. Only other wiring is the RCA cables from the head unit, which i fed through the center console and then under the carpet, and the rmeote power lead from the head unit which I fed along with the main power wire (I try never to feed power wires with RCA cables to help keep any electrical interference from getting injected into the rca cables). What remained was the ground wire, which was simple as there is abolt right below this location (under the board the subwoofer sits on, which pops up and usually houses your CD changer if you have one). This subwoofer also has a remote control for the bass level, which I routed the wire to my center console. I had a blank cover in my center console which wa not used (same size as your heated seat switch or power window switch), which allowedme to mount the control knob in this blank cover by drilling a 9/32" hole in it, so it looks stock and is unobtrusive.

I am very pleased with the sound quallity of this setup and it is far better than the stock Volvo system, and allows me many future upgrades.

Important Speaker/Wiring Information:
Here is the bare bone specifics on the OEM speakers to keep in mind when looking to replace them.

Dash: small 1-way 8 ohm peaker
Front door: mid 1 way 6 ohm speaker
Rear door: mid 2-way 8 ohm speaker
Rear pillar (wagon) or Rear shelf (sedan): 8 ohm speaker

The ohm rating is important to note hear. Most car speakers will be 4ohm speakers with some being 2 ohm. Volvo wires their speakers a little strange. The dash and front door speakers are wired separately. However the rear door and rear pillar (or rear shelf) speakers are wired in parallel, which mean your rear speaks are all wired to a single right and left channel, which makes those 2 sets of 8 ohm speakers a set of 4 ohm speakers. Most car amplifiers and amplifiers inside the head units are 4 ohm rated. So if you leave the OEM speakers in the car and just replace the head unit (and use the head unit's amplifier) then your front speakers may seem to be quieter than normal, this is because of the OEM speakers being a higher ohm rating. So if your head unit says it produces 50 watt per channel at 4 ohms, then driving an 8 ohm speaker with that amplifier would basically mean you are only giving them 25watts of power, while the set of parallel wired 8 ohm speakers in the back will be louder since they are working as 4 ohm speakers and would be getting the full 50 watts of power.

The Infinity speakers I chose are 2 ohm speakers, driven by the amplifier in my head unit, which is rated at 4 ohms. However, the head unit is a 4 channel unit, and I am driving 6 speakers. So I wired my dash and front door speakers in series on the front channel. Wiring them in series produces a set of 4 ohm speakers, which matches the rating of the head unit, which produces its full rated power. My rear door speakers are also 2 ohm, but at the moment I have not put in the extra set of speakers in the rear pillars, so they are being driven at 2 ohms by the head unit, which effectively doubles the wattage output the head unit produces. (it isnt exact but baically if you half the ohm rating of the output rating of the amplifier, you double the power, so a 50 watt aplifier at 4 ohms would be producing 100 watts at 2 ohms). Once I add the last set of speakers the rear speakers will also be wired in series to produce 4 ohms.

It is very important to keep in mind the ohm ratings and usage, to avoid potential damage to your speakers or amplifier. Most amplifiers (and head unit amplifiers) are stable when running at 2 ohms, although most are rated at 4 ohms. If you go below 2 ohms you risk damaging your speakers or amplifier. Some high end amplifiers are stable at 1 or even 1/2 ohm but these are expensive...do not do this unless your amplifier specifically say it is stable that way. Practically all head unit amplifiers are not stable below 2 ohms.

Wiring my speakers as I have mentioned was easy to this point. Volvo already had all the necessary wires pulled to the dash. To hook my dash and front door speakers in series, you would not hook them up directly, wire to wire between the wire harness and the head unit (doing so would just wire each speaker individually to the head unit). To wire them in series (to make two 2 ohm speakers act as 4 ohms) you would do the following:
- Hook up the left positive speaker wire to the positive connection speaker #1 (dash).
- Hook up speaker #1's negative connection directly to speaker #2's (front door) positive connection.
- Hook up the left negative speaker wire to the negative connection on speaker #2.

Since all these wires are already pulled to the dash by volvo, you do not need to run any extra wires, instead, simpley connect together speaker +1's negative wire to speaker #2's positive wire in the dash by the head unit. This produces the same effect.

The problem comes later for me to hook up the rear speakers in series, since they were originally hooked up in parallel. Since I cannot easily trace how the wired these speakers, I will have to pull a new wire from the rear door to the rear pillar to hook those speakers up in series, in order to guarantee not causing potential damage to my head unit. This will not be a simple wire to pull, which is why I havent bothered with it yet. Because I am using a pair of 2 ohm speakers it is imperative that they be hooked up properly. Accidentally hooking up a pair of 2 ohm speakers in parallel will produce a 1 ohm load which can very easily damage the amplifier in my head unit, as well a possibly damaging my speakers. So, it is possible that I could use the wires volvo already ha in place, but I would rather not risk it.

As for hooking up a separate amplifier to power your speakers, it is a relatively easy thing to do, but keep in mind a few things, if you decide to also add 1 or more separate amplifiers.

- Basically, you would hook up an amplifier the same way as I did the powered subwoofer above, except you will also need to run wires to the speakers it is going to power.
- Keep track of the ohm ratings capable of the amplifier and the ohm ratings of the speakers you are using. If you are going to wire speakers in parallel or series, it is best to stick with speakers of the same rating for simplicity. Example: Two 4 ohm speakers in parallel would produce a 2 ohm rating. Two 4 ohm speakers in series would produce an 8 ohm rating. ( i mentioned how to hook up speakers in series, to hook up in parallel you simply hook the positive speaker wire from the head unit to the positive connection on both speakers and the negative from the head unit to the negative connection on both speakers).
- Do not overpower your car without proper planning. As a rule, I never put more than 500 watts of power (regardless of the ohm rating, whatever the ohm rating I am using, I never exceed 500 watts) without taking other meaure to insure proper power handling. Over 500 watts, I will them begin to provide the vehicle with better power handling abilities (ie: adding a second battery, upgrding the alternator, etc). Exceeding 500 watts can begin to cause power drains on your car, and with many modern cars with alot of electronics and computers, causing uch power drains can cause problems, not to mention dead batteries and dead alternators.

Now my 500 watt rule (this is just my rule anyways, not some standard set in stone), is based on using separate amplifiers, and I usually do not include the amplifier rating in a head unit. Good amplifiers are much more efficient than cheapo amplifiers you may find at flea marketaudio places, wal-mart, etc. Cheapo amplifiers are quite often very inefficient, have poor sound qualityand are rarely capable of the wattage they advertise. In my opinion I would suggest staying away from such cheapo amplifiers. It is common for many amplifiers to advertie a wattage capability that they really never achieve, so plan accordingly.

Also, when buying speakers, do not be fooled by their advertised peak power capacity. You do not want to supply this amount of power to your speakers. Go by the RMS power capacity of the speaker when choosing an amplifier, as well, go by the RMS capacity of the amplifier. The peak power rating is the maximum the speaker can handle (or amplifier can produce) before damage is going to occur, and even then the peak number is only to be achieved in short bursts, never full time use. As an example, my 3-1/2" Infinities, have an RMS of 25 watts, but a peak of 75 watts. If I powered them with 75 watts for any extended period of use, I would most likely blow the speakers or melt their coils (not to mention the would sound like crud and be filled with disortion).

As with any full system upgrade it is best to do your research ahead of time, buy everything you need before starting the project. If you can get all components before doing the job, so you dont have to come back later and tear everything apart again to add something later. Some later additions are simple, some may require removing your head unit again, just keep this in mind. A full system upgrade can take awhile to complete, and purchasing an inexpensive wiring harness for an aftermarket head unit can be a life saver and possibly save you from damaging your investment if you are not familiar with having to hardwire the system yourself.

I hope this info is helpful to some. Feel free to add anything else or if you find someone inaccurate, please post to correct me.

Good luck :)

now that is what i call an informative post. thanks blakbyrd.

Haha, well I have always been cursed with writing long posts. Eventually I may add some photos for people better understand some of the modifications (though very little was needed), to see what all was involved.

I used to be one of those "bass head" type of people who could rattle the teeth out of the people in cars around you (although I have always hated rap). After having a $6000 system stolen, I just dont do that anymore, and my music tastes are a little more toned down. I still like my bass, but I now prefer it to be in check with the rest of the music.

A stereophile I will always be though, and I like good sound, not just loud and disproportionate. The car stereo end was always just a hobby, although I used to be a hi-fi home theatre/stereo installer for $100k systems, so I am picky about my sound being right :P

Sound is of course a personal preference, and my choices would not fit the desires of others. I do not suggest for people to do exactly what I have done, but rather offer it as a potential way to compare items they may be considering. However, I am never one to suggest cheap over quality.

With the system I did, I have less than $1000 in it, and it took most of Saturday to install properly (would have taken much less time if I just wanted to get it working, but I am picky and I wire things correctly and cleanly and verify all connections prior to hooking things up instead of just assuming a wiring diagram is correct, a I have seen far too many that were wrong).

I am happy to give any other specific details about my system if people want. If anyone is curious, even using the stock amplifier from the head unit, my system is far louder than what the stock volvo system was and is capable of rattling the car quite well, but I dont listen to music that way anymore. There is no need for it to have another or separate amplifier beyond the one in the subwoofer. Granted it isnt for competition..haha. Sound quality is excellent and crispand balaced as it should be so that you cannot easily distinguish speaker location (beyond already knowing where they are :P )

see, we are the flip side of the same coin. you've installed $6k woth of stereo equiptment for the bass, and i've paid $40K for a modified engine to do burnouts with. okay, so you were a little excessive. :grin:

Well, I have always wanted to be able to do such types of engine mods. I;ve alway been a do it yourself'er, as I like to do the actual work, but engines are something I really don't know much about and prefer not to start messing with. I'm an electrical/computer/gadget guy more than engine work. So I stick with what I know. Newer engines can be rather complicated compared to beefing up older american cars without all the electroinics and senitive equipment controlling the engine.

Besides, I have never really had any car with real raw power. I started out with a 1976 Saab 99GL that was a 4 cylinder tank (totaled 4 other cars with it before it was finally totalled..haha).I moved up through the ranks of other 4 cylinders, only once owning a 6 cylinder which was in an old tyle 1969 Ford Bronco (one of my off road builds), but it was an in line 6 Ford 300 transplanted from a 1969 Mustang.

I will work on just about any part of a car, especially supensions and stereos, but engines just intimidate me, and I prefer not to screw around with em..haha.

After quitting my off road hobby, I am now largely into leaving things as they are and focus more on computers and servers now.

I must admit thought I was a hair away from dumping the car stereo idea to installing a full blown PC package in the car instead (which I had all planned out but I held off on the idea). Until the price of solid state hard drives comes down alot, I decided to hold off on this idea or now, but probably in the next 2-3 years will be upgrading to a full pc instead of a car stereo, so I can have my internet and computing also available in the car :)

That actually is an extremely helpful post. Well done and thank you. But a quick question to Blakbyrd.

I'm planning on putting in a new set of front and rear door speakers into my 97 850 wagon but like you mentioned before, every website especially Crutchfield, has different data and fit guides for my car. Some say 5-1/4" do fine and others say modifications needed and 4" instead. I'm guessing the reason why is because you could only screw in two of the screws?

I know the dash's are 3-1/2" but I'm still unsteady about purchasing the 5-1/4" because your 95 850 may be even that slightly different from mine. I don't want to spend close to $200 on something I need to add another $100 too.

I realize you own a slightly different care, but your very knowledgeable and I'd appreciate any advice.

-Chris

I am only guessing, but I believe the 97 is still basically the same (I believe even the aftermarket wiring harness is the same for both). However, I have not verified this yet, so it is only an assumption.

As mentioned in my main post, 5-1/4" speakers fit nearly perfectly in the front doors. Just laying the OEM speaker and new 5-1/4" speaker on top of it (cone to cone), you will have to pull out a mm ruler to see any difference in size. I have no clue where Crutchfield came up with their 4" idea, as it seems like alot more work to fit in a 4" speaker, when a 5-1/4" fits without having to do any cutting, and matches up to two of the existing mounting holes anyways. As I recall the main reason all 4 do not line up is because Volvo uses an odd shaped mounting bracket around the speaker cone (this is most evident on the rear doors as the speaker bracket around the cone is not round, and the hole location are more at 45, 100, 275,and 315 degrees and not the more standard round locations at 45, 135, 225 and 315 degrees (basically every 90 degrees)).

Anyways, 5-1/4", in my opinion could not have fit more closely without modification, and I did not need to do any modifications to the front doors at all. 2 Opposing screws hold the speakers in perfectly fine. The remaining 2 holes only lack reaching theInfinity mounting holes by less than 1/2 and inch and making a small metal piece to adjust for this would not be difficult and would allow all 4 screws to be usedif you feel you need them and it would not require you to do any alteration to the car should you ever put the stock ones back in.

As for the rear doors, the speakers are slightly larger than the front doors (close to a 6 inch speaker, but good luck finding a 6" speaker). Some people have put in 6-1/2" speakers, but that requires ome modification to the door and the inability to use the original Volvo speaker grille. Since the rear door speakers are slightly larger, none of t hemounting holes line up for a 5-1/4" speaker (you could use one hole if you want to mount the speaker off-center but I dont like doing this, and it would rewuire fabricating a mounting bracket for any other holes. Mounting a 5-1/4" speaker in the center allows the mounting tabs of the speaker to properly overhang the opening enough to drill small holes through the plastic (no metal to drill through here, so it is simple) and mount the speaker with 4 sheet metal screws, justmake sure you drill the holes maller than the screws (#8's are plenty good). What you would be drilling into is a removable speaker housing (glues to the oem speakers, and the plastic surround on the door that the platic housing bolts to which is also the same screws that bolt the OEM speaker in place). Mounting the speakers as I did, allowed me to still use the 4oem screw just as they originally were, but they just dont hold the speaker as well, instead there is room to properly add the new screws, as mentioned and nothing gets in the way of each other.You can maintain using the oem speaker grilles also. You will also have to drill holes in the plastic housing for your new wires though.

If you want to try to maintain your Volvo in as near original shape as possible, you do not have to use the plastic housing (I did becaue it aids in letting the speakers produce slightly better bass). You can leave it out and just drill holes in theplastic surround on the door. Should you ever put the OEM speakers back in place, the plastic housing you removed will cover over the holed you had to drill and until someone actually went to remove those speakers again, they would never know anything was ever put there.

I have been busy the past few days (out of town on service calls, and will be again tomorrow), but I will get some pictures to put up for people to see better what I am talking about and it may allow you to see if my 1995 is the same type of setup as your 1997.

Of note though, is speaker height (not depth here as the doors are nice and deep). The distance from the mounting plate of the speaker to the top most part of the speaker (usually the top of the tweeter on a 2 way speaker). You have a little less room on the rear doors than you do the front doors. The Infinities I used probably stck up slightly more than most as their tweeters can be rotated, which you do bu puching them in and rotating them, which means they are spring loaded to lock in place, and as such stick out slightly more than non-adjutable ones.

Out of curiosity, what kind of system are you looking to install? Are you just replacing those 4 speakers, or are you looking to replace the head unit and thedash and rear pillar speakers as well?

I mention this becaue you will be throwing the ohm balance of the speakers off by just replacing the 4 you mention, which might prove problematic. From the wiring harness in the car (by the head unit) it appears Volvo is powering the dash and front door speaker separately, but the rear door and rear pillar speakers are powered together (wired in parallel). As I noticed during the speaker removals, the dash were 8 ohm, the front door were 6 ohm, the rear door were 8 ohm and the rear pillar were 8 ohm. Because the rear door and rear pillar are in parallel on one channel they are producing a 4 ohm load on the head unit's amplifier, which is perfectly safe and allow them to output slightly louder than the front. However almost all aftermarket speakers you buy will be 4 or 2 ohm speakers (most are 4 ohm, but mine were 2 ohm). If you leave therear pillar speakers hooked up and replace the rear door speakers with 4 ohm speakers, you will be wiring a pair of 4 ohm and 8 ohm speakers in parallel, which would produce a 2.66 ohm rating, which will make the rear speakers considerably louder than before (this should still be safe on your head unit, but I would not go any lower, meaning do not use 2 ohm speakers in your rear doors or you risk damaging the amplifier or head unit itself. As for varying loudness, you can use the fader to balance them out better, but for a stock or aftermarket head unit, do not dip below a 2 ohm rating with your speakers. Most head unit amplifiers are rated at 4 ohms, so if your head unit produces 50 watts at 4 ohms, and you wire the rear speakers as mentioned here under a 2.66 ohm load, you will be driving those speakers at a maximum of around 90 watts, so keep this in mind when choosing your speakers. You want to try to match your amplifier power rating as best you can to the RMS rating of the speakers (not the peak power rating), so simply buying a 50 watt RMS 4 ohm speaker and wiring it so that it is under a 2 ohm ratingmay not end up sounding very well as you may begin to over power them.

Please take note, I do not know for certain if Volvo is powering the dash and front door speakers separately, I only assumed it by the wiring harness (separate wires for each, colored differently), but I do know the rear door and rear pillars are powered together. I didnt care much since I was replacing the head unit anyways, it is possible that they just pulled the wires direct to the head unit since they were so close and are wiring these speakers in parallel also, just as the rear and the head unit is just a 4 channel, and not a special 6 channel head unit (since there is only a fader option front and back and not any means to separately control the 2 sets of front speakers, which would be relatively common if they had their own amplified channels), becaue of this, without actual verification, I would stick with the same rule as the rear speakers when considering ohm ratings. If you do not replace the dash speakers, then do not use 2 ohm speakers in your front doors. If you do replace your dash speakers, then I would suggest using 4 ohm speakers in both locations (up front) or using both 2 ohm speakers and rewiring them in series (if you use 2 ohm speakers and leave them in parallel you may very well damage your head unit, as you will be creating a 1 ohm rating which can damage most amplifiers) Further options for over 4 speakers is to begin adding cross overs and separate power amplifiers, but it isnt necessary if you keeptrack of the ohm ratings and how you wire the speakers, as well being able to control the frquency to the speakers (they will sound like crap if you allow full range through tweeters or smaller 2 way speakers). Luckily my head unit has a complete cross over system built in that allows me to set the frequency sent to each pair of speakers, as well as eash speaker coming with its own crossover.

The situation I ran into was powering 6 speakers (3 pairs) with a new head unit that only had 4 channels, so I had to combine 2 sets of the speakers. I combined the dash and front door speakers, because they were both 2 ohm speakers. I wired them in series instead of parallel, which gave me a 4 ohm rating, which is the standard rating of my head unit amplifier. My rear door speakers are also 2 ohm, and once I add therear pillar speakers I will wire them the same way giving a matched set just as the front.

Anyways, I am sorry for the long post again.If you have specific questions, feel free to PM me or ask here, and I willanswer as best I can. If you have specific speakers in mind, that might help as well, as will the type of music you prefer to listen to and whether you want to be able to listen rather loud or if you typically jut listen at normal or lower levels.

Good luck, I will try to pot some photos tomorrow night.

Thanks Blackbyrd for the information.
And yes, photos would be great. You can still use the Edit function to add to the posts.

:clap: :clap:

I don;t mean to be redundant, but here is the link to all the photos, large and small on the install for those interested in seeing what was required and how things fit (in case someone is considering a system upgrade).

A I write long posts, many people will skip over my previous posts that they have already seen and not notice the editied original post, so here is the link again:

Stereo System Upgrade Info with Photos

I didnt post the photos directly here as there are a bunch and my post is already plenty long. I can do so if it is preferred, although I just threw the page together quickly, and there is nothing else to see at the site (no ads, nothing, just this page), so I'm not trying to advertise for my website..haha. Actually as someone who does webpages for others, the simplicity of this page is embarraing to me, but I just wanted to get it up there for people.

Enjoy.

Ok the pictures are done. Below are just a couple of the factory looking dash, front door and rear door, to see if the compare to what yours looks like. If so, you can use the link afterwards to see all the installation pictures and information on everything done to make everything fit. Larger pictures of the ones below are also available at the link at the end.

Dash (driver side)
(IMG:http://www.blakbyrd.com/Car/DashSpeaker_sm.jpg)

Front Door
(IMG:http://www.blakbyrd.com/Car/FrontDoor_sm.jpg)

Rear Door
(IMG:http://www.blakbyrd.com/Car/RearDoor_sm.jpg)

Full Info and Pictures

Hope this helps. Feel free to ask any questions if needed.

The pictures are a perfect help and YES, they are the same, which is great for me. I appreciate your help a lot. I'll make sure to focus my after market speakers at 4 ohm so they balance out to a solid rating. The car you have, speaker wise, looks identical to mine, so your measurement I will use to buy mine, I'm sure they havn't changed drastically enough. The drilling you mentioned sounds simple so I shouldn't have too much to worry about.

Thanks again blakbyrd!

Glad I could be of help.

As for the drilling, you could even do it without dripping by using elf tapping or machine screws. Since it is just plastic it wont take much effort to get a screw to bite into the plastic. However, you can risk cracking the plastic in this manner if you use the wrong screws or screws too large.

As for the system you are looking to do, you will have a larger range of speakers to choose from if you use 4 ohm speakers. All 4 ohm speakers are not alike of course. Some are far more efficient than others. If you stick with 4 ohm speakers then you should be able to stick with the stock wiring that is in the car.

If you only replace the door speakers then the sound balance between the door and dash and door and rear pillar may be a little different than you are used to, due to the remaining speakers still being 8 ohm. It is just my personal preference to maintain all speakers at the same ohm rating when pairing them up (doesnt mean all speakers in the car have to be the same), but I just like to keep things simple.

2ohm speakers are also fine, but you will have to wire them in series, which you can do behind the head unit if you want, if you happen across some speakers you really like but are 2 ohm.

If you are new to replacing car stereo speakers, I may be able to help offer some brand suggestions depending on the type of music you listen to and how you like to listen to it, as well as some possible ways to keep to a certain budget if you have one.

Good luck though, the job I did wasnt too hard. I spent about as much time online during it trying to validate certain wires as I did actually installing the stuff. I spent most of Saturday doing it, but it really doesn't have to take that long.