Cobbling together a car sterio

[TallPaul]

My '95 F150 came with a sterio radio and 4 speakers. Recently there has been an annoying rattling noise in the higher frequencies, sounds like it is coming from the speakers, not bodywork. The stock radio does not have a lot of amplifier and I will typically run it at a level of about 12 out of 15 max.

Yesterday I pulled the rear speakers and hooked up two small cabinet speakers, probably 18" by 12" by 7". These are 6-8 ohm rated. I am not getting volume unless I run the rear speakers only and set it at 12 out of 15 on the volume, and then it is not as loud as the factory speakers, though there is a ton more bass. I have to keep the bass halfway or lower, whereas the factory speakers I was turning bass up to about 12 out of 15.

Seems the box speakers are pretty good but at the higher volume seem to lose clarity. So I obtained an Optimus 100 watt sterio amp (50 per channel) at a garage sale for $2. Supposed to work. Only thing I notice is that where the fuse goes into it, the plastic is melted. So either it is a fire hazard or the guy was pushing it way too much. I figure with the amp, I should be satisfied at about 8 out of 15 on the volume control and so the amp won't be pushing too much wattage and hopefully not overheat. But then again maybe it is already toast. Only way to find out is to hook it up.

My plan: household #14 wiring direct from battery with a fuse at the battery. Will run the rear speakers through amp and probably just run rear, unless I find the stock front speakers add any sound quality.

So maybe this will work, maybe not. Worst case, I go back to the stock speakers and just live with the annoying rattling because other than that they did sound pretty good, though the bass was weak.

Anyway, thought I would toss this out hoping to get some wise advice from folks who have wired up their own sterios.

If these box speakers are junk, I do have a set of "New Advent" speakers from 1979 that really sound great. Used to shake my 10x12 suburban bedroom with them when I was a kid, driven by a 65 watt per channel Yamaha amp.

 

[bretfraz]

A few comments, if I may:

1. Car audio speakers are typically 4 ohm and most amps are designed for that impedance. For best performance and sound quality, I think you are best off keeping everything the same and not using speakers made for a home stereo amp.

2. It sounds like your factory speakers are blown. After 14 years, I think they've served their purpose. Have you considered installing replacement speakers in the same size, installed in the factory location? The size is 6"x8" and there are plenty of aftermarket speakers to choose from. Go to Best Buy or ABC Warehouse and see what they have.

3. Alternatively, you can install a pair of 6x9's in boxes and place them behind the seats. That will give you more bass than the OE install location, and there is a large selection of 6x9's on the market.

4. As for the amp, you are going to need a line level / line output converter. I do not think your Ford radio has low level RCA outputs, only outputs from the radio's amp directly connected to the speakers. Amplifying an amplifier will create a lot of distortion and overall bad sound. A line level converter steps down the radio's amplified output and provides proper RCA connections for best sound quality and performance. You can find them for $20 online.

Good luck. Your truck should sound rockin' when you are done.

 

[MGregoir]

Your best bet, and simplest bet would be to simply replace the rear speakers with a good quality $50 to $60 aftermarket pair.

For under $300 you could replace the head unit and all four speakers. You'd finish with a very good sounding system for the money.

You can even get wiring adapters so you don't cut a single factory wire in the installation.

You hear your front speakers from the door much more than you do from the rear, and that is where most of the mids and highs come from in the "sound stage."

If you go to Crutchfield.com, select your vehicle, and choose a stereo that does what you want it to, and front and rear speakers, they will send you all the hardware you need to wire it in easily and mount everything. I wouldn't be surprised if you could do it for $260.

 

[VK56VD]

Buy a new headunit. This may make the old factory speakers come a live. Worst case scenario, buy 2 sets of new speakers if you won't like t outcome. 6x8/ 6x9 speakers are usually really good at reproducing decent bass.

Check Ebay for a used Alpine or Kenwood mid range headunit and you'll be set.

 

[TallPaul]

Thanks, Good advice, though I am trying to do this without spending much if any money. The amp spec is "Matching Speaker Impedance: 4-8 ohms" and the speakers are 6-8 ohm per the label on the back. So it should work. This amp has input for RCA hookup and separate input for if you don't have RCA outputs, which I'll check but doubt it has RCA being a factory stock basic radio. But the amp has a second imput section for without RCA application where you just input the speaker wires. I'll have to see how much distortion I get. There also is a leveler on the amp to adjust the level of audio signal coming in. It may be that if that is set lower it will not distort as much. I'll see. If it does not work, then your advice on the upgraded speakers would be easiest.

 

[bretfraz]

Good deal, Paul. I hope the amp works out OK for ya.

 

[VK56VD]

I have a feeling the stock stereo is getting tired and does not have enough omph to push after market speakers properly.

 

[TallPaul]

Yep, I am just being a cheap bastoid.

The timing of the amp at the garage sale is just too coincidental, seems it was meant to be. So I think it will work. Gonna try.

 

[Jimmy9190]

I'll chime in here. If that amp has a melted fuse, you need to have it bench tested and repaired before proceeding any further. Even if it does work it's a fire hazard until it can operate without drawing so much current to melt its fuse.

Do not use house or residential wire for your power connections. You can get an amplifier installation kit with the correct stranded wire in the correct gauge for all the power, ground and remote turn on leads, zip ties, ring terminals, fuse and fuse holder, rubber firewall grommet, etc for less than $20.00 at Walmart, Best Buy, or any good car audio store.

Once you have an amp that works, it is best to use a line-level convertor for the best sound quality. You may not need an amplifier if you replace the rattling speakers, like others have suggested. If you need better sound, an amp and good speakers will definitely help. You can often find a good deal on an amp with free installation or reduced price speakers if you buy an amp, etc at Best Buy. Independent car audio shops will offer installation too.

 

[mpvue]

even though you want to do this on the cheap, to me, time is money. you are going to spend a whole lot of time trying to cobble this together and not be happy w/ the results.
don't bother looking for line level outputs on the factory stereo; I haven't yet seen a factory head unit w/ them.
you'll have to use the speaker level inputs, which'll sound like chrap. stepping down high level to low level, only to amplify it again messes w/ the signal quality too much.
you should not use household wiring for the supply. household wiring is solid, not stranded. it is not designed for vibration inside a vehicle. you need stranded wire.
IMO, used audio equipment is used for a reson; the seller replaced it because it was junk. so, you get what you pay for.
last but not least, it's spelled sterEo

 

[The_Jeff]

I'm familiar with those ultra cheap radio shack amps. Can probably find a pdf manual online. I got one wanting to make a cheap stereo system in college, based on a CD player RCA outputs, and it couldn't do it.

They DO take speaker level inputs. Although the wiring could be hacked, lack of RCAs on the input wiring would say to me they take speaker level in.

Probably your new speakers are less efficient than the old ones, soaking up precious power in the crossovers needed to make them 3-way compared to the stock speakers.

 

[sciphi]

I bought 4 new Kicker speakers for $130 shipped from Crutchfield, 4x6's and 6x9's. Made a world of difference even with the stock Delco headunit in my Buick.

My recommendation is to pick up some used name-brand speakers off Ebay or Craigslist. Also ask at your local stores if they have any demo or floor-model speakers they're willing to cut you a deal on.

 

[TallPaul]

Yeah these cabinet speakers date probaby to the 80s or worse. I should check that they are not dry rotted, eh?

My only serious concern is fire hazard. In theory the fuse should blow and I wonder if the prev owner put too much load on it and put too big of a fuse in it, to result in the melt. Either that or I was a sucker at the garage sale, but for $2 I figured worth a cr-ap shoot.

Okie Dokie, stranded wire works for me. Easier to route too.

Hey, before I spring for new speakers, I'll pirate the speakers out of the motorhome. We never use them anyway. Actually they already are pulled--yeah, maybe just put those in the truck and leave the amp for plan B. I'll try that first. See, all this discussion made me think of the motorhome speakers. Now where did I put them?

Sterio--

Just checkin' whether any of you guys knew how to spell it, of course.

 

[TallPaul]

Originally Posted By: eljefino
Probably your new speakers are less efficient than the old ones, soaking up precious power in the crossovers needed to make them 3-way compared to the stock speakers.


Another option is to open them up and cut out the 3-way so that only the woofers are wired up, then run front for tweeter and rear for woofer. Might work.

Amp has input for RCA or speaker. Manual (I downloaded) says RCA will give cleaner sound. Don't think radio has RCA.

Another thought is that the amp is toast from playing volume too high (12 out of 15 max), as I heard never put amp volume above about 6 to 6.5 of 10 or distortion will mess up amp and speakers. The other radio may be better but is not easy to tune for the radio MP3 broadcast.

 

[Jimmy9190]

Actually Paul, Optimus is some really old outdated electronics. The sound quality between car audio units nowadays compared to a factory system using a Radio Shack Optimus amp is like a night and day comparison. I would encourage you not to use the Optimus amp, even if it does work without melting the fuse. Technology has come so far in car audio nowadays that just a head unit alone has better power and less distortion than the Optimus amp from the yard sale. Most modern headunits will also have either a USB or an auxilliary audio input for your MP3 player too, which is also night and day compared to the FM transmitter method. You can buy a good quality MP3 ready CD head unit these days for around $125.00 on up, depending on where you purchase it. And your 95 F150 is one of the easiest vehicles ever built for replacing the radio. Just my 2 cents but I would upgrade the radio and replace the worn out OEM speakers before adding that old amp to an old OEM radio.

 

[TallPaul]

Maybe it would be best to install the amp so the truck burns up, then buy a new truck that already has all the good sound stuff.

Yeah, I know, if only I bought a good system life would be simple, but actually the new radios scare me, they look very complicated to operate. I want a twist knob for volume and simple buttons for selections. Generally I just run shuffle in the vehicle as it eliminates the need to fiddle with the sterio while driving.

True, the radio in this truck is a piece of cake to pull.

What is the amp in the stock radio? Does it have 4 amps, two for front and two for rear, or just two amps split front and rear?

 

[Jimmy9190]

It's actually 2 amps, one for the left channels and one for right. You could still replace the old speakers with new aftermarket ones and still give a better improvement in sound quality, as some others have replied here. Even Walmart sells some good Pioneer speakers for the F150 for a low price. I would still try that before integrating an archaic Optimus amp. In its day Optimus was OK stuff, not the worst and certainly not the best. I installed a fair amount of Optimus gear because the stereo store where I worked was right next door to a Radio Shack in a college town. These days though, you can do better and smaller for less money. But for 2 bucks and a wire kit from Walley World, you have nothing to lose by trying it to see how it sounds. AAP and AZ also sell amp wire kits.

 

[TallPaul]

Originally Posted By: Jimmy9190
It's actually 2 amps, one for the left channels and one for right.
Oh yeah, thats right, it would have to be left and right. Can't really get stereo on a single amp.

Motorhome speakers are the next step. As I recall they are about the same size. Just got to figure out where I stashed them.

As for plan B, Wiring is easy. I have 20 ga speaker wire. Need to get some power wire, 16 or 14 gauge stranded, a heavy duty fuse holder, and a toggle switch (not going to try finding the radio power output line for switching on/off with radio unless it works and becomes permanent. That is not the power line, but a separate line for switching only.

 

[The_Jeff]

Let the naysayers say nay. In an F150 in motion you'll hear enough other stuff to negate any minor changes in sound quality. It's quantity you need, and that you shall get.

The new head units are almost all designed for 12 year olds with blinky blue lights and other junk that's distracting at night. I had one that went back to "best buy rack" mode when I disconnected the battery and had to dig deep into arcane submenus to turn most of that stuff off... and couldn't turn it off all the way!!!

If you need cheap hook up wire, go to the dump where they have all the TVs and stuff and cut the cords off! Strip that down and get lots of 6-8 foot lengths of fine stranded copper in about the right gauge!

 

[TallPaul]

Well, it appears that it may be the amps in the radio (headunit I guess you're all calling it). Left channel seems a bit worse than right channel. I put the motorhome rear speakers which looked almost identical to those in the pickup and even said Ford on the back (Chevy Motorhome, but these are from the coach, not the cab). The motorhome speakers are 4 ohm. Seems that more ohms = more bass to some extent, though also suck more power as I found out with the 6-8 ohm Scott speakers.

So, tomorrow, I'll put the tape player version of the radio back in as the amp should be better on that. Main reason I switched the tape player radio out was that it can't easily tune by frequency. Have to go through some complicated process and it didn't seem to work, but I'll play around with it again. If the tape player radio sounds better, then maybe try the extra amp and Scott speakers again.