StereoMan’s Motivations

StereoMan delights in the mental challenges as well as the craft of repair, and the pleasure of working in a situation that requires him to listen to music constantly. He derives great satisfaction from knowing that his work is providing lasting enjoyment to his clientele. And just as importantly, Steve takes his environmental stewardship very seriously, making every effort to keep perfectly good equipment out of the landfill.

StereoMan loves problem solving, whether it’s troubleshooting a broken stereo component or designing a home entertainment system. He enjoys meeting new people and through his clients hearing music he hasn’t heard before. It’s great fun getting to know someone and sharing the richness of our experiences.

In the end, we all do our work to make money so we can pay our bills and – if we’re fortunate – enjoy the finer things in life. What a blessing it is when one’s work is also one’s joy!

StereoMan’s Experience

What experience does StereoMan have? Trained for electronics in the U.S. Navy, Steve’s electronics career includes ten years in two-way radio and five years in Common Carrier (the precursor to cellphones).

Steve started repairing stereo equipment in 1986, working as an independent contractor for Gibbs Radio Company. He subsequently provided service for three other local shops, as well as developing a personal clientele for StereoMan.

Steve has installed thousands of 12 volt sound systems, repaired thousands of stereo components, installed hundreds of home stereo and home theater systems, and maintains several commercial Public Address and background music systems.

Speaker Rebuilding in 12 Easy Steps*

It’s inevitable. Even with better quality speakers, there comes a time when the foam material that holds the cone to the basket is going to deteriorate, and eventually crumble away.

What do you do then? You could just throw them away and buy a new set. But if you really love the way they sound, it’s going to be really hard to get used to something different. Or, you may be one of those people who hates to throw something away when it could be easily restored to like-new condition. Good for you! StereoMan says “There is no away.”

How can you tell if your speaker foams are giving way? Take the grille off of the speaker. It should pop off fairly easily by prying at the corners. Look for cracks or tears in the foam. If they’re really far gone, you’ll see holes where material has fallen away.

Materials needed: Phillips screwdriver (sometimes allen wrench), flat blade screwdriver, putty knife or paint scraper, disposable rags or paper towels, acetone, round lid or plate of appropriate size, magic marker, one sheet of adhesive-backed paper labels, replacement foam surrounds and speaker repair glue (or “speaker rebuild kit”), painter’s masking tape (the blue stuff), nylon cable ties, jeweler’s screwdriver or dental pick

Step 1: Remove the speaker from the cabinet. Usually there are four or six screws holding it in, typically phillips heads but sometimes allen heads. Then you’ll have to pry the speaker out with a flat blade screwdriver or similar tool. It may take some effort as the speaker is often very tightly fitted. Work your way around the perimeter applying steady pressure until the seal breaks. Sometimes there will be a sealing ring under the speaker. Hang onto it! Also note the difference between the two wires on the speaker. They may be different colors, or one may have a stripe. One of the terminals on the speaker will have an identifying mark. Note which wire goes where.

Step 2: Remove the old foam. You may want to change your clothes first, and put on a pair of gloves. This is the nasty part. You’ll need some acetone, a putty knife or paint scraper, and lots of paper towels or rags that you won’t mind disposing of afterwards. They will be ruined.

Use a towel wetted with acetone to rub away the foam residue from the edge of the speaker cone. If it doesn’t come off easily, use more acetone and take more time, rather than using more pressure. If you tear or crease the speaker cone, the party’s over!

Around the rim of the basket there may be a plastic or cardboard ring over the foam edge. This must be removed. Use your putty knife or screwdriver to gently pry it away. If it’s cardboard, don’t worry too much about damaging it; replacement cardboard edges are easy to obtain. A plastic ring is proprietary and therefore breaking it would be problematic. So don’t do that.

Once you’ve removed the ring, pour a couple of ounces of acetone around the foam edge residue and let it soak in for a few seconds. Then start scraping away with your putty knife. The residue will stick to everything! Use more acetone to soften it, and wipe it away with a rag or paper towel. Repeat as often as necessary until you’ve removed almost all of the residue.

You don’t have to get every last bit. Remember, the new foam has thickness to it. Bits of residue no thicker than heavy stock paper, or beads no larger than a grain of sand will not be a problem.

Step 3 – Draw a circle. Here’s where the lid or plate comes in. The purpose of the circle is to give you guidance to center the new foam. Choose a round object that is about 1 1/2 inches less diameter than the speaker cone. The new foam is going to overlap by a half inch or less. Remember, this is not rocket science, you can be an eighth of an inch off center and it will not be a problem. Trace around the perimeter with the magic marker.

Step 4 – Shim the voice coil. Carefully cut away the dust cap in the center of the speaker cone with a SHARP exacto knife or box cutter. Cut right at the perimeter to avoid damaging the voice coil, and don’t cut too deep or you’ll cut through the cone! In addition, I advise scoring a small (1/4″) radial line across the boundary between dust cap and cone, so you can tell exactly how the dust cap should be oriented when you glue it back on.

What to use for a shim? This is where the sheet of labels comes in. You need something that is of absolutely uniform thickness, but very thin. It must have a slick surface so it slides cleanly between the magnet and the voice coil. It must be flexible, yet rigid. So what you do is . . . you peel off the labels and throw them away, and then you use the waxed paper backing! Cut two pieces about two inches wide and long enough to wrap around the magnet exactly once, minus an eighth of an inch. Work the first strip down between the magnet and the voice coil. Work the second strip down between the magnet and the first strip, so that the eighth-inch gap is on the opposite side. Voila! Perfect shim!

Step 5 – Lay a bead of glue around the perimeter of the speaker cone. Speaker repair glue is specially formulated to dry clear even though it’s white when wet, and remain flexible for years and years. Parts Express sells it in a 1 ounce bottle – just the right amount to repair one pair of small to medium sized woofers.

If you’re doing a pair of 15s or 18s, buy two. Don’t skimp on the glue!

Step 6 – Secure the new foam to the speaker cone. Carefully drop the new foam into place. Try to get it very close to right on the first try, so you don’t have to move it around once it’s hit the glue. If you do have to adjust its position, make sure you keep it a perfectly uniform circle. Be gentle!

Once you’ve got it centered nicely, tap lightly all the way around the perimeter with your finger to get the glue to soak into the foam. Don’t press! Just tap. Tap tap tap. All the way around. Twice around. Three times. Glue is liable to ooze out along the inner edge of the foam. Don’t worry about it.

Now tear off (or cut) 12-20 two-inch strips of painter’s masking tape (larger speaker, larger number). Absolutely accept no substitutes! This stuff will not stick to the speaker glue, even after it begins to dry. This is most important! Apply the first piece of tape to overlap the inner edge of the foam, and very gently press it down to the foam. Next, make a

crease in the tape along the inner edge of the foam. Finally, press the tape down to the speaker cone. Once you’ve got it on there right, it will look like the photo above.

Work your way around the cone, overlapping each piece of tape with the previous one, making sure you get that tape to crease along the edge of the foam so you’ll get a nice, tight bond. When you’re done with the last piece, it will look like the photo at right.

Step 7 – Wait several hours. Depending on how much glue you used, and how warm it is in your work area, anywhere from 3 to 5 hours for the glue to get good and tacky.

Step 8 – Remove the tape. Don’t just yank it off. Release one of the outer corners of the last piece you put on (it’s the one that’s on top at both ends). Peel it straight back, don’t pull it up. If you take off that first piece and the glue still seems wet, wait a while longer. Repeat for each piece of tape. They should come off without disturbing the foam or the glue. If you accidentally pull the foam up along the way , tap it back down. Tap tap tap. Put a piece of tape on that spot. You can take it off later.

Step 9 – Replace the outer ring. Lay a bead of glue around the inner edge of the speaker basket rim. You’ll have to lift up the outer edge of the foam to get it in

there, but that’s where you want it. Tap the foam down into place, like you did on the cone. Tap tap tap. Three times around. Then press the outer ring back down into place. Be sure to make the holes line up with the screw holes in the basket. Tape the dust cap to the speaker cone so you don’t get them mixed up in the next step. If your speaker had the cardboard type gasket, and you have to replace it, here’s where I get mine:

Caveat: MAT has a $25 minimum order. Workaround: they’ll fill an order for less, for an extra $3.50 service charge.

Step 10 – Overnight drying. . Turn one speaker upside down on top of the other. Put a nylon cable tie through each screw hole and tighten them down uniformly. Let dry overnight.

Step 11 – Remove shims and reglue dust cap. Pull straight up on the shims to get them out. Gently. At this point, press down on the speaker cone with your fingers on opposite sides. It should move freely without the voice coil rubbing against the magnet. Rotate the speaker 90 degrees and do it again. If there is any rubbing at all, you have to start all over again. But if you followed these directions carefully, I guarantee it will come out right!

Remember the score line from Step 4, right? Line up the score line on each dust cap

with the score line on the corresponding speaker cone. Then use a jeweler’s screwdriver or a dental pick to settle the dust cap close to its original position. Don’t worry about a tiny gap here and there. The glue will fill it in. Once you have it settled, lay a bead of glue around. Let it dry for a few hours.

Step 12 – Reinstall the speaker. If there was a gasket under the speaker, now is the time to put it back in. Then hook up the wires. Remember, it makes a difference which one goes where. Not a big difference, but a difference. Then line up the screw holes and screw it back down. Tighten all of the screws a little bit at a time to seat the speaker nice and evenly.

* I shouldn’t have said “easy”. It’s not really that easy. Sorry! But hey, now you know why StereoMan’s $35 per speaker charge is a real bargain!

Handy Tip for March 2010: Play Your iPod Through Your Stereo

You don’t have to replace your original stereo!

Most cars nowadays come with a pretty good stereo, but they only play AM, FM and CDs. How do you plug your iPod into it? Where’s the jack? Do you have to buy a new stereo just so you can listen to your iPod?

A set of earbuds is probably not the solution you’re looking for. Maybe good for you, but what about your passengers? And guess what: wearing earbuds while you’re driving could get you pulled over.

A better solution This little device is called an “FM Modulator”. You can buy one at your favorite Box Store, or online, or you can get one from StereoMan.

How it works It comes with an adapter cable that plugs into your iPod’s headphone jack. The cable carries the sound into the device, where it is converted to a broadcast. That’s the “modulator” part. The broadcast is very faint, so the device has to be connected directly to your car stereo’s antenna jack. That also means it won’t interfere with nearby drivers who might actually be listening to the radio.

Installation There are three connections to make on an FM modulator. First you pull the antenna connection out of the back of your car stereo and plug it into the jack on your modulator. Then you plug the modulator’s antenna connection into the stereo.

Next you have to connect the “hot” wire and “ground” wire. The hot wire should go to a 12V source that switches off when you turn off the key. You’ll need a multimeter or a test light for this. Make sure you find a good solid ground for the ground wire. Hint: the stereo chassis will do very nicely!

Last, you have the audio cable. On some modulators, the cable is permanently connected. On others (like the one pictured), you’ll see a standard pair of audio connections on the unit. The other end plugs into your iPod’s headphone jack.

Stashing the modulator If you’re going to travel much, make sure you don’t hide the modulator too well. You’re going to need to access it to change the frequency it broadcasts on. If you’re not going to travel, you can tie the modulator behind the stereo with plastic cable ties.

StereoMan can help If you’re not into doing it yourself, StereoMan can install a modulator in most cars for about $25.

A Digital Primer

High Definition? Digital? HDMI? Whaa???

It’s all so confusing!

Let’s start at the beginning: DVD’s Actually, before DVD’s there were Laser Discs, but let’s not muddy the waters with insignificant details! With the advent of DVD’s, we consumers had our first experience with digital video, AND our first experience with high definition. DVDs offered the viewer twice as many lines of resolution as VHS videotapes. We were all blown away by how sharp and clear the video images were. Back in the day. Like, last century.

Along came Digital TV It was only a matter of time before television broadcast designers figured out how to use the digital technologies used by DVDs and computers to broadcast video signals over the air. And then the FCC mandated that all broadcasters switch over to digital, because it uses so much less bandwidth.

Is Digital TV High Definition? Not necessarily! Low definition videos can be broadcast digitally just as easily as high definition videos. In fact, they often are – reruns of old TV series and made-for-TV movies, for example. But for sure, before there was Digital TV, it was not possible to broadcast in Hi Def, whereas now almost all current programs are broadcast in Hi Def.

Three kinds of high The “Definition” of a video refers to the number of vertical lines of resolution in the picture. Standard DVDs provide 480 lines of resolution, which is lowest level of high definition. Purists will tell you that it’s not high definition at all, but those of us who remember VHS will offer an argument to the contrary.

Most digital tv is broadcast at 720 lines of resolution. This is what purists call “true” high definition, but it’s not the highest high.

1080p and the Blu Ray disc This is the highest of high definition formats. Some programming is now being broadcast at this level. All Blu Ray discs are recorded at this level. The “p” means “progressive” and it refers to the way the video shifts in its entirety from one individual frame to the next. Contrast to “i”, which means “interlaced”, a method that shifts every other line of the image at a time. Interlacing uses less bandwidth, but results in image “jitter”.

Four kinds of cable In the old days, we had a black cable with a screw on connector called an “F” connector. It screwed onto the antenna terminal on our old picture tube sets, and we tuned in on channel 3 to watch the video. Then we got the “composite video” cable, which transmitted the video signal directly into the set without changing it over to a broadcast. This reduced the distortion of the video by eliminating one level of conversion.

Composite video was good, but it wasn’t good enough for “true” HD. We needed a cable that could separate the three basic components of the video signal – called “luminence”, “blue differential”, and “red differential”, thus eliminating another layer of
conversion by not having to combine them into a composite. What better way than to use three separate cables! Hence the “component video” cable, with its characteristic green, blue, and red color scheme.

Component video is really good enough, but it’s not ideal, because A) it’s still introducing a level of conversion, from the digital source to analog, B) it’s kind of bulky to have three separate cables, and C) you still have to have an audio connection. Why not do it all with one digital cable? Enter the HDMI! Here we have a single cable of relatively small diameter, with a handy flat connector at either end, to carry a digital video signal AND a digital audio signal.

Which is best? StereoMan absolutely recommends using HDMI wherever possible. They’re actually quite economical, as long as you don’t make the mistake of buying at the Big Box Store. You can have the convenience of buying directly from me at a very good price, or I will gladly tell you where to get them online for an even better price, if you want to go to the trouble and save a few more bucks.

Handy Tips for January 2010: Cleaning your Discs

How to clean a CD or DVD

You spend a lot of money on your CD’s and DVD’s, so it is understandable that you want to protect that investment. If you get smudges or fingerprints on the playing surface, you don’t want to ruin it trying to get it clean.

The right stuff: CD’s and DVD’s are made of polycarbonate plastic, so the best cleaning solvent to use is the same one you use to clean your countertops or windows. Select a cleaner that leaves no residue.

The right method: Your digital media disc does actually have a “groove” just like an old vinyl record, just much narrower and not nearly as deep. Foreign material stuck in the groove will cause playing errors. Use plenty of liquid, and let it soak for a few seconds before you wipe it off.

Use a soft, lint-free cloth to wipe off the liquid. A paper towel is okay as long as it’s soft. When you wipe, resist the circular motion impulse, moving instead from the center to the outside circumference. That’s because if you do scratch the surface, a radial scratch will not affect playability, but a circular scratch will! Apply only light pressure. If it doesn’t come clean, use more liquid.

Wipe it until it’s dry. Any residue will affect playability just as surely as a fingerprint, a blot of mustard, or a crumb of cheese.

The right storage: StereoMan shouldn’t have to tell you to keep your digital media discs stored in a proper receptacle. But what if you can’t find that plastic “jewel case”? Keep a few ziplock sandwich bags handy. They’re just the right size, and will keep the playing surface clean and dust-free.