Well I'm up to the 1990s now. Just found a stock CD player unit for my car. Now with a decent source, the speakers are really making me gag. So i need some information to replace the speakers.

It looks like I have 2 6x9s in the back, 2 5 1/4s in the front. And as much as I can barely live without those idiotic little paper holders, I read in my search that I can replace them with 1 1/2 in tweeters.

Now for the questions.... and please understand i have been out of car audio since we had to use drivers from home speakers and hack holes in everything to put the speakers in. I'm assuming things have progressed since then.

- Do they make speaker pairs of 5 1/4s and 1 1/2s wired. Such as in series, or with a passive crossover. Or do I have to run a second pair of wires from the door to the amp for the tweeter?

- What are the benchmarks for sensitivity of the speakers relative to the amp section. I can get an answer to that in either of 2 ways. The wattage output of the stock amp into a 4 or 8 ohm load. Or a stated speaker sensitivity that you guys knows works best in the usual SPL/1w/1m measure. I imagine the power supply in the stock amp has all of the thunder of a gerbil fart, so i'll be looking to be fairly efficient, but still must operate in the amp'* power sweet zone.

Thanks guys. Any guidance will be appreciated.

OOOK

you are correct you have 6x9'* in the back and 5.25 on the door and you dont have the tweets i see

you can replace the 'Business card holders" with tweeter grilles that match the larger speaker....(I can get you the factory tweeters and grilles if you like ......im going to the junkyard this week)

From what i have seen in the Bonnes.....the doors are prewired for the tweeter, even if they are not there stock.....the way this works is that both pairs of wires carry the full signal, then there is a bass blocker on the tweeter to prevent certain freq from damaging the tweet

you want to go with a 4 ohm speaker, that is what almost all of the aftermarkets are anyway

Prewired, that'* excellent news. It wasn't so much having to wire back to the amp section, as figuring out where to tap it into the unit. Plus there was an issue of wiring 2 speakers in series. The ohm load on speakers is a nominal rating. It actually varies during playing. when you put 2 speakers in series, you half the load, say to 2 ohms. Amps don't generally like that so low. And in practice, dynamics of music could cause the amp to dump which could fry the output stage and/or the speakers.

Thanks for the offer on the tweeter stuff. I'm a yard hound, too. I was going to get the grills there. But i didn't think of it till you mentioned, trying the stock tweeter is a great idea as I'm not seeing many 1 1/2 inchers at the Net stores. I can tray them ans see how they balance with whatever 5 1/4s I get.

Cool thing, too. I noticed you guys have 2 and 3 way 6x9s. That must be SO much better than the stocks. That way you get moy better mid/high frequency fill from the back. High frequencies have such narrow dispersion. And those single cones probably didn't put out much to start.

The only thing left i think is matching the sensitivty of front and back. It looks like most of the car speakers are in the 90-95 db range, so that shouldn't be too hard. I just don't want them off so much, I can't compensate with the fader.

Thanks for your help.

If there'* anything I'm missing ,let me know.

Yes you'll want something with an 89-95 dB rating. That should be good for your stock HU. The GM headunits are not THAT bad as far as power goes, but they do get a little weak in the higher volume range. When looking for front speakers, go to http://www.crutchfield.com/whatfits and enter your car'* info. Then look for component speakers for the front, a 5.25 inch set. That'* the easiest and best sounding, albeit the most expensive option. Component sets come with a midrange, a separate tweeter, and a dedicated crossover for each speaker set. This will give you the most separation and tuning ability compared to just having stock tweeters and "bass blockers". Get yourself a nice set of co-axials for the rear. Do keep in mind though, the best thing to do for sound is get a better head unit. Yes, the Delco units are good, but at a MAX i bet they're only putting out ~ 25 watts. I'm sure you already know underdriving speakers is just as bad as over-driving them.

Good! the plot thickens. I went to crutchfield and looked at the "component" drivers. That'* a good idea because you know the two drivers are matched. The stock tweeter with the highpass filter isn't inherently an inferior approach, it just makes it a little trickier to match with the 5.25. But thats good, i didn't know if they had started making that type of thing (component setups)

I'm hearing you loud and clear about the head amp. No sustitute for building your system from a good source pre-amp/player, then add a bucket of clean watts with an amp. i noticed some of you guys are even bi-amping, cool.

I'm trying to correctly max out the stock unit. Probably gonna try for the most efficient speakers that still have good headroom for dynamics and maybe someday... MORE POWER. Plus it'* stupid to lack an MP3 input, that'* half of my music. If I can get 92-3 db out of a watt or two, then ~25 watts will cleanly get me to ~100 db in dynamics. The only thing I can't do is run it at 98 db and expect it to jump without clipping the amp.

Thanks for the info. I finally got some time to really read your threads, i have to admire the stuff you guys are doing to get max sound in your cars. Car audio is a real biyatch to do well, because cars are an acoustically lousy space to recreate music.

i should give you guys a good preachin' about some of your sub woofer setups. Some are trying to defy basic laws of acoustical physics, and you're blowin' some money on extremes that ain't gonna happen.

But.... it would be just like my dad telling me that my new Led Zeppelin (their first) album was an annoying perversion of the blues and he would appreciate it if i didn't play it in the house when I was home from college. Don't listen to us old folks. the older you get, the more ya become a tightass...

No. You double the load when you put 2 speakers in series. 4 ohms in series with 4 ohoms = 8 ohms.

You halve the load if you put them in parallel. 4 ohms in parallel with 4 ohms = 2 ohms.

And if you use a crossover with a highpass filter for the tweeter, and a lowpass filter for the bass speaker, then the load remains effectively unchanged. 4 ohm tweeter + 4 ohm bass speaker in parallel using crossovers = 4 ohms.

hear ya. That'* right, the load is seen from the amp tap.. Both wires would have to come off of the tap.

Yeah, i saw no problem with the filters, they are just frequency resistors if I'm not mistaken.

Since i'm catchin up on these "componet" setups for the 5.25. They probably are worth the extra bucks. I didn't realize the "tweeter" actually handles some midrange, too. That causes more issues matching the aftermarket 5.25 with the stock 'tweeter", even with the equalizer.

Personally my advice is to do what I actually did with my SE; junk the factory speakers, go with matched 5.25" + tweeter separates in the doors, and go with a good 2 way or 3 way 6" x 9" in back.

My door separates are Boston Acoustics matched components, and my 6" x 9" speakers are Boston Acoustics 3-ways. Now I went with an aftermarket Pioneer CD head unit and a 4 channel amp, but you could easily keep the factory head unit if you like, and just upgrade your speakers to component separates for your doors, and get good matching 6" x 9"* for the rears.

If you don't want to drop a ton of money, there are some good values out there in Pioneer and similar brands. Just swapping in aftermarket separate component speakers for your factory speakers should give you much better sound. Wiring is a snap because the matched separates for the doors come with their crossovers (high pass for the tweet, low pass for the bass). It doesn't matter [to you, anyway] where the crossover frequency is, as long as both speakers are designed to handle their part of the spectrum, and the designers of the matched separates do this for you already, so all you have to do is literally buy them and drop them in. The front wires from the head unit goes to the crossover that you tuck into the door, the tweeter wires up to the high tap on the crossover, the bass speaker wires up to the low tap on the crossover.

There'* absolutely no muss, no fuss, no planning, no calculating. It'* dead-simple. Just get a pair of tfactory weeter grilles to replace your business-card-holders. Get them from a dealer, or ask in the "wanted" forum, because the junkyarders in our group are always pillaging those out of junkyards.

Then if you want to expand it later, you can upgrade the head unit, add amplifiers, etc., but you can certainly just upgrade your speakers for now and get a huge improvement. We'll guide you through anything you need info on; taking the door trim off, etc., that'* what we're here for! Why re-invent the wheel? Take advantage of the knowledge of those who have gone before you!

That'* what i'm doing. Picked up the stock to aftermarket conversion plugs today. 2 infinity Reference 6x9s are on the way. I picked them because they can run fine off of a few watts, but have a a very high powerhandling capability, in case I get carried away and want to up the HU and amp section. Plus the midrange/tweeter is aim-able to the listening area.

In the front, I'm going to run an Infinity Reference component set. It'* a nice match and will lessen or solve the major design screw-up in the Bonneville audio system. Your ears aren't in your calves. The midrange/tweeter of the Infinity can be angled and/or flush mounted higher on the door.

At retail, it'* more than I wanted to spend. But if you are used to dealing with internet salesmen of cameras and audio equipment in Brooklyn, the spaekers can be had for 10% over cost plus shipping. BTW, markup on most quality audo equipment is 100%.

"We'll guide you through anything you need info on; taking the door trim off, etc., that'* what we're here for! Why re-invent the wheel? Take advantage of the knowledge of those who have gone before you!"

That'* what I'm here for. thanks to everybody BTW, I worked with Henry Kloss who mentored the guys who started Boston Acoustics, Cambridge Audio and Bose. he was the father of the "Boston" sound. I also worked for Stereophile, when it was owned by J. Gordon Holt. I hope I can contribute back to BC some acoustical engineering experience.

Those are some great choices, Charlie! And welcome to our group. Pretty much anything I've ever needed to do with my Bonneville, there were people here who either already did it or had some good tips to add. I really love this group.

You hit the nail on the head with angling up the tweeter in the door'* tweeter hole. That'* exactly what I did, and it really does help. The sound still comes from down by your knees, but angling it definitely helps the imaging. I like the clean look of the door with the stock speaker grilles, and they hide your tweeter mounting secret.

You'll get much better sound out of the Infinitys compared to the stock speakers, and when you're ready to add an amp, you'll be all set.