audio questions

[myp71]

I'm going to become MECP certified (Mobile electronics certified professional)installing car electronic equipment I took a pratice test and got a couple of questions wrong on the audio part of the test so I wanting to know if there is any simple audio info that you guys might know of that might help me out a little?At least until I get my study book from mecp

[Chris Smith]

Rule #1....there are no short cuts to learning.
Just learning it self. <p>It depends on how many questions they will ask and on what subjects relating to sound and its equipment? <p>Anything from electrostatic handling to Decibels?<p> Learn it all, be prepared?

[myp71]

Yeah and there is a lot to learn.The stuff I really don't care to get into because I never really cared for it like passive crossovers and what causes static on the speakers buzzes and hums Mostly stuff I will not use very often or run into the problem.<p>I thought that there might be a little (info)or something that would help a little bit to find out what I'm getting into <p>[ January 21, 2004: Message edited by: my p71 ]</p>

[John Paul]

HI,<p>I found these car audio forums, the first one is an MECP forum.<p>MECP forum<p>
Car audio forum<p>John Paul.

[myp71]

Thanks John Paul that helps a lot<p>Myp71

[amuron]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Mostly stuff I will not use very often or run into the problem.<hr></blockquote><p>Those are the things that set an a top notch installer apart from the rest and generate the best income. It may be that he will never have to design a box, or adjust a passive crossover, but the knowlege of the how and why, will help. Same deal with hum, or trying to remove alternator noise from the clients favorite long distance AM talk radio show.<p>For example, it seems most installations are done by idiots who have no idea what they are doing.<p>For some odd reason, even commerical vendors hire do a bad job. Its probably economics based. If they can hire a high school kid for $8/hour, why should they hire a good installer for $40/hour. Most of the time, the kids work will hold up for 6 months to a year, and by then, the client forgot who put in the audio or burgler system.<p>Then when the clients audio system is acting up, they bring it in to have it repaired at a pro audio shop, as by then the kid at the freebie installer retailer is gone, and all the remaining guys know it would not be practical to fix it. Most of the time, it ends up being a rip out, and start over.<p>Now if someone put in the wrong cap in the passive crossover (it does happen), and is blowing tweeters out, a good installer will take a look at the cap value, and the tweeter, and can fix it, thus on the way to earning a client for life.<p>There are lots of amateur installer, and lots of idiots who think they know what they are doing. The MECP certification should help in weeding out the idiots, and in the process help you, especially when it comes time to redo the work done by an idiot. I think the test is a little too underpowered, and like many, lacks actual process issues, and instead dwells a little too much on theory, that is used infrequently. I can understand the test writers viewpoint. If they want to get a wide market for MECP certification, and they get involved in quality processes, the freebie retailer installers would have a fit when their techs came back from taking the test, and refused to cobble things.<p>Sorry about being a little harsh, but its such a pita to fix something that should have been done correctly the first time around. OTOH, such repairs do bring in a lot of money and earn customer good will.<p>Good luck in your studies and passing the test.
Ron

[myp71]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by amuron:
If they can hire a high school kid for $8/hour<p><hr></blockquote><p>Do you really think so? Good because I'm just finishing up HS and plan on getting a mecp cert basic installer because that is what you have to start out at then you move up a least one year but no more than two years.I think that $8.00 hr is good for just starting out doing something that you really like doing.<p>If you can pass the test that companies give you and/or pass the mecp test there is no difference between the next guy.<p>Also I think $40.00 an hr is a lot the most I have seen is $22.00 an hr for a 4-5 year experince then become a install manger.<p>But I do have to say thank you for the "good luck on the test" encouragement

[amuron]

Its hard to hire a decent high school kid for $8. Most want more, the good ones deserve it. Some are hardly worth minimum wage.<p>If you get your MECP basic installer cert, have the drive for excellence, continuous learning, get the top MECP fabrication a while later you should do well. If you want the big money, get into custom fabrication, eg pods, enclosures, and run your own shop, $40/hour is not unrealistic, double that should be possible.<p>For example, if someone spends $3000-$5000 for a system, they will expect a top notch custom install, and will pay for it.<p>As far as comparing to the next guy, it comes down to craftsmanship and attention to detail. A guy who can thermoform panels, custom fab aluminum, and run a vacuum bagging molding operation is about 10 steps beyond the rest of them. Then add in the skills of postive top notch personal skills with the client, and you he will be way ahead of the rest. <p>The market at the top is small, no doubt, but if Alpine and the other big names can develop equipment with retail prices of several thousand dollars, they are 100% sure they will get a decent financial return from it. The installers can captilize on this as well.<p>Most install shops cater to the 16-25 market where cheap is the rule. Some of those youngsters actually pay $1000 or more for their unit, but will grumble about paying $200 for the install. Install shops such as those are great to get your feet wet. You get to learn a great deal while making money, and you will become efficient. Just rememeber to work towards craftsmanship and speed. <p>Too many places emphasize speed, and not quality, and do not even provide the right tools for the job. Some rely on the installers for tools, and realisitically they will have a tough time spending $2000 for a wide variety of the proper crimp tools. As a result the installer uses 1 or 2 sub par crimp tools, and hopes it will be ok, or in some cases does not know the headaches that will result. <p>Crimping wires is insanely difficult to do correctly even with the proper tools. Most of the time, a poor crimp will last long enough that the customer upgrades before failure, but not always. <p>I used to think crimping was a set it and forget it operation. When we had to rewire 200 X-ray machines due to an improper setup on a $30,000 computerized crimping machine, I got wise really fast. The crimps looked ok, but were slightly out of tolerance. They also passed out QC visual inspection and pull tests, but became intermittent in the field. We had Amp engineers on site for 3 days before we got it resolved. After that, we had go-nogo gauges made, and ran inspections on the machine setup daily. We probably shipped out 2000 of the machines over the years since then, and never had a crimp failure.<p>Again good luck with your test
Ron

[myp71]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by amuron:
Crimping wires is insanely difficult to do correctly even with the proper tools. Most of the time, a poor crimp will last long enough that the customer upgrades before failure, but not always. <p>Again good luck with your test
Ron<hr></blockquote><p>Yeah just to be sure with the crimping I solder the connection also.You can never get the guage of wire to match your crimp.<p>I don't think I need luck What I do need is to study a lot but luck won't hurt.I'm getting my mecp study guide this week so I will have to wait and see what happeneds when I open it <p>Thanks

[amuron]

There are two problems with soldering. One is efficiency, it takes extra time. The other is the need to clean the flux, and many cleaners are harmful to automotive interior parts. No clean fluxes often times are not active enough to work well on slightly oxidized copper, and the fumes in a confined environment can be bad news.<p>As far as crimping, here is a IPC training demo that may be useful in your study. It doesn't go into depth, but does give a good overview.
http://training.ipc.org/demos/pdf/drm56.pdf<p>You are correct, luck on tests should not be a big factor. Sometimes the test writers do a poor job, at which point luck does enter in.<p>Another thing to do with your studying is to create your own problems and solve them. For example, a customer complains that their dash lighs dim with the music. Make a list of everything that could cause the problem. Then create a troubleshooting and repair flow chart. In the process you will gain some good analytical skills.<p>Best regards
Ron

[Mr. K]

Thanks for the link, Ron! More to it than I realized.