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Re: Some questions about the repair business

5/25/2003 4:31 PM
Re: Some questions about the repair business
A place for everything and everything in it's place.  
Has anybody ever read about the custom hot rod car builder who's legally blind? I read an interview and he said that if he didn't put his tools back in their place he would never find 'em again.  
Now, where did I put those wire strippers??? LOL
5/27/2003 5:30 PM
Jack Collins

My bench (actually my whole work area) looks like  
a tornado just went through it right now.  
I have actually went out and bought a new roll of  
solder because I couldn't find it (I'm still looking for that one).  
I have several pairs of clippers and needle nose and somehow I end up looking for those too...  
Thankfully the soldering iron is connected to a  
5/28/2003 2:45 AM
Tim Gagan

I saw a sign today that said "Organized people are just too lazy to look for things."
6/14/2003 3:58 AM
Bob H.

I did repair work for four music stores in St. Pete FL in the mid eighties and did good repairs for reasoable rates. $35 for first half hour then $35 for each additional hour. I would pick up the units repair them and return them as soon as possible. The stores would add about 25% to 33% to cover their time taking in the units and paper work. Then one store I found out was actually charging 100% of my bill in addition to my bill and that didn't sit well with me so I dropped them, so be careful when working with a music store they sometimes will take all they can. Have an agreement in writing for the amount they can tack on.
6/27/2003 5:08 AM

Jeff Seal inadvertently pointed out one of the main problems with commercial musical electronics repair. He mentioned that he worked on an old Fender (fun and easy!)a QSC power amp (New and sucky!) and some other stuff like microphones, etc. in the same day. You can't just work on what you want, you have to take what comes through the door. Some of the stuff (Peavey) uses lots of proprietary IC's, you can't get them locally. You have to stock them and they are expensive, keep in mind that Peavey is the largest music equipment manufacturer in the world.  
Then, you have Mesa Boogie. California Peavey. IMHO, ten pounds of shit in a five pound bag. Very difficult to work on and lots of odd sized, proprietary parts that they don't have at commercial electronics stores. No schematics unless you know a dealer, and you will need them to fix their stuff, zillions of little circuit boards and ribbon cables. More proprietary parts. The vendors that sell generic parts sometimes have minimum orders, and always have stuff on backorder. That's just guitar stuff. What about power amps, mixing boards (beer spillage) and all the other electonic junk that can eat you alive timewise. You may or may not be able to find a schematic, and schematics are not always right or particularly useful. They don't tell the whole story. You don't get 30 bucks per hour for every hour you spend troubleshooting, sometimes simple stuff takes forever. A little bit of electonics training will not prepare you to effectively compete with those that are experienced in this specific type of work. I learned tubes and digital/analog electronics in the US Navy and spent 6 yrs repairing military electronics to component level. When I got out, I was not really prepared for commercial electronics repair, it is different because you start from scratch with no documentation and different equipment every day, and no parts depot. I don't mean to discourage you, but you should be realistic about the job, the customer expectations and your abilities. Most of the time you fix junk practice amps for almost nothing with the wrong parts. Unreasonable customers(i.e. musicians!) will hound you relentlessly while the work piles up. Dealers intent on profiting on your service will commit you to unreasonable repair schedules, and you will have problems getting parts for obsolete (>5yr old) equipment. That having been said, it can be a very fun job. It was a side job for me, I chose to get paid in equipment, all of which I still have! I worked for a high end used/new dealer in Richmond, Va. for a couple years and worked for an old Hiwatt DR103 signed inside by Harry Joyce, a Matchless Superchief 120, a '62 Jazz bass, and countless cool pedals, etc. I wasn't trying to feed my family, if you are good enough to do this work, you can make tons more money in a day job! Everybody wants to be the Tube Amp Guru, that is the easiest part of the job, even after you learn how to massage amps to give a musician more of this or that. The day to day stuff is the hard part.
6/27/2003 7:11 AM

Wow Pete, gotta disagree with your analysis.  
I work on an old Fender, a current QSC, and a microphone, and I think it is a good day. DOn't get to work on what I want? WHo does, but I would hate to work on the same damn thing day in and day out. That is the glory of this job, I see everything. I also rebuild jukebox amps, and some of them are pre world war 2. I can go from the very newest thing to something from 1938 in the same day. That is better than having cable TV.  
Besides, my shop is authorized for both Fender and QSC. ANd Peavey.  
What are you referring to with Peavey? I can't think of anything I would rather see come in my door. Their stuff is straightforward, readily serviced, and they support it better than anyone in the business. I called Fender for a EQ pot for a guysSuper the other day - Hah, nothing like it in stock so I found something on my own. Peavey? Call them for parts on your 25-30 year old Peavey amps - they'll have it.  
I fix them all the time. The older stuff is a bunch of 4558s and TL074s, and not much else. The power amps if they blow are inevitably a couple output xstrs and maybe a driver or two. If the drivers go, check the resistors that serve them.  
One chip they did use was the TL604 - a switching circuit for channel select of something like it. These are a stock TI part but no longer available. Nothing custom. They have made a work around for this part. You won't catch Fender dooing that. Peavey may put house numbers on things, but an SJ6357 is just a MJ15003 - and yes I stock them. If you work on Peavey you ought to download their semiconductor and transistor cross reference list. It lists the house numbers and their generic and even suggests subs in some cases. If you find their 87478 chip, it is just a CA3094.  
I very rarely buy parts locally. The electronics store in this town carries the NTE line - which I avoid - and not much else for semis - oh, some TTL and CMOS. I buy from OEMS and national houses like Mouser and Allied. But 4558 and similar are cheap and used by a million brands, so of course I stock them. I also stock TDA2050, MJ150xx series power xstrs, and lots other. But I dont stock everything, I order what needs to be ordered.  
On the other hand I totally agree about the Mesas. I hate seeing them come in. And I had a VHT that was the same way, and hated it.  
While I mostly fix guitar amps, I enjoy the other as well. I see darn few of my mixer repairs with drink spills in them. I have seen just as many guitar heads with a drink down the top vent grille.  
If beer gets on a mixer, it goes in the sliders, can't really get in anything else. Sure a big mixer can ne incomnvenient to have on the bench - on my cart table really - but it is straigtforward.  
I don't care so much what I work on because troubleshooting is troubleshooting. Everything has an input and an output and a power supply. Go from there. I have a large schematic collection, but if a big mixer came in with a dead channel and I had no print, I would look at the card for that channel. I would expect to find a couple or three ICs - dual op amps I bet my lunch money - and some controls. There are usually a couple isolating resistors in the power rails as they enter the card. Shorted IC often burns them up, otherwise the resistors seldom go bad. I can look at pins 1 and 7 and if I see DC there, I know the chip is bad or that is drives an LED.  
Practice amps? I think of them as free money. Those amps are all the same inside. WHat goes wrong? The break the jacks, they break the controls. WHen it blows up it is the TDA chip. There will be a 4558 too usually, and if it is bad, you will know it easy enough. I charge $30 plus parts for a practicew amp. I can't imagine why it would ever take more than 20 minutes to fix. Between those big jacks that fender used and the standard japanese ones I can buy cheap at MOuser, I cover most jack needs.  
I charge a minimum of $60 for a blown up power amp in a head. While once in a while it can get invoilved, I rarely use an hour to do the repair. I fixed a Peavey XR600 amp in eleven minutes from start to burn in table. I am not bragging, it is just the same old same old. (Yes, we checked all the functions before we released it.) I am getting ahead on my minimums and I don't do repairs for next to nothing.  
I service for several dealers, some smaller, amd one very large. I am not held to a schedule. I established at the outset that I would look at everything that comes in within 48 hours. At that point it is either fixed or wiating for parts or maybe inspiration. No one takes advantage of you unless you let them.  
Sure there are unreasonable people out there, especially the musicians, but the vast majority of folks are nice, polite, and reasonable. I had a guy once drop something off on a saturday when I was closed. He called as I got here the following monday and wanted to know if it was fixed. And why not, after all I have had it for two days!! But that is the exception. If it is an emergency I rise to it, otherwise they get in line.  
To me the day to day stuff is the easy part. Hard? OK, I have a MArshall AVT something in here, and about once a month it will let out with an ear piercing BRRRAAAAAWWWWKKK. I have no idea why and I can't make it do it. It only does it when IT feels like it. THAT is hard.
7/1/2003 2:00 PM
I also disagree Pete, coming from a metrology lab (meters) and doing calibration and repair, I find I can fix damn near everything I've seen. (except where it's not economical to repair)  
I'm the only one in the area who can fix most of the SS and digital crap, noone wants to touch it, especially the old tube amp guys. they look at SS stuff and their eyes just glaze over. i can look at it and start seeing the circuitry in my head.  
This weeks repairs:  
peavey ultra (thanks for the help Enzo!)  
Crown power amp  
Carvin w/noisy reverb  
Fender deville  
Digitech whammy  
Crate vc6112  
mesa triaxis  
the only one taking a while is the crown, i had to wait a few days for parts....and it's rreeeeeeaaaaallllyyyy blowed up good!

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