Why Techs are Cranky

[chipprogr]

I have no idea what you are talking about, I am an authorized Mackie repair station. They certainly have no "swap boards first" sort of policy. I am sure if I called them and said the existing board is unrepairable - burnt up or whatever - they would come up with a board. But we are expected to repair the boards in the products.

Same here ENZO, +1 on all that. Im authorized Mackie too and your right, they want s to fix the boards if we can at a reasonable price.

[Ronsonic]

I have no idea what you are talking about, I am an authorized Mackie repair station. They certainly have no "swap boards first" sort of policy. I am sure if I called them and said the existing board is unrepairable - burnt up or whatever - they would come up with a board. But we are expected to repair the boards in the products.

Many manufacturers now have "do not repair" lists. Those are entry level inexpensive products they would rather exchange complete than pay $50 to have repaired. But I can;t think of any factory that expects board swaps.

There are a few manufacturers who "prefer" board swap only, but they are also the ones that pay very, very little and refuse to allow extra time for a diagnosis and repair. Mostly companies we don't want to deal with anyway.

The DNR lists are a little surprising sometimes. Enzo mentions the FM212R which is the largest DNR unit I've seen. In fact, I accidentally repaired one once before checking the list. Fender paid it.

The big issue with a lot of them is availability of sub-assemblies and service information. So much stuff is completely outsourced that many "manufacturers" are mere brand names and everything behind the front panel and feature list is subcontracted. The brand just mocks up what it's supposed to look like and do, and then opens the containers from the Far East and sends them off to distributors. Others do more of their own design and manufacture but obtain things like power supply or DFX boards from the lowest bidder.

[Enzo]

My first warranty FM212R, I just assumed it was "big" enough to repair. It needed a speaker. I called fender parts. "Well we can get one of those I guess, but it will take awhile. You know that is on the DO NOT FIX list, don;t you?" Well, no I didn't, thank you. Cancel that speaker order.

[jrfrond]

BTW- who the f*** are ya callin' "cranky"???

[AudioWorks]

who are the two mackie certified houston shops. Even music city was years back when i was still there. I remember fighting with mackie over the phone for some reason or other. Is mars one of them? One thing i like about mackie is all the free service manuals unlike some companies. I think the company i have the worse time dealing with would be b52 just because of a few recent troubles.
I actually repaired a huge shipment of 10 harbinger speakers which b52 makes from what i found out. Im not authorized with them but thanks to the client being a dealer i was able to get 12 15 inch and 6 diaphragms reasonably priced. Had to rebuild all the cross overs to. That wasnt what bugged me about b52 though, it was alotta problems over several past repairs.

[Enzo]

B-52 doesn;t know me from Adam. But my one real interaction with them was me emailing for a schematic for the AT100. I had no idea if they would be responsive or not. The next day, I had the schematic, a tube layout, a bias procedure all waiting in my email box, plus the return message made several suggestions. All in all a very positive response.

[R.G.]

I watch with some amusement the start of using switching power supplies in musical amps.

I made a living designing switching power supplies for a few years. It is ==>NOT<== the same as other power supplies. Trying to switch (not wobble!) high currents and high voltages at high frequencies is demanding of both electronic and mechanical precision.

Everything matters. Where the current goes matters. Where the conductors go relative to each other, and to ground, matters. How long and how wide the current carrier traces are matters. What's on the other side of the PCB matters. How close the PCB is to the side of the box matters. How thick the power transistor insulators are matters. How much heat sink goo you use matters. And of course, how hot and how well heat-sunk the entire thing is matters.

Guys who are good at other kinds of electronics will make, as we used to say "self-eating watermelons" when trying their first high power switching power supply. Exploding semiconductors and capacitors; smoking holes where resistors and PCB used to be. Ever seen a diode or a fuse explode? Electrolytic capacitor goo on the ceiling?

If the companies that do this are smart, they'll hire a company that specializes in designing switching power supplies to design their internal power setups, right down to the placement of the mounting bolts. If they're not - well, they're going to have a few field failures.

[jrfrond]

I watch with some amusement the start of using switching power supplies in musical amps.

I made a living designing switching power supplies for a few years. It is ==>NOT<== the same as other power supplies. Trying to switch (not wobble!) high currents and high voltages at high frequencies is demanding of both electronic and mechanical precision.

Everything matters. Where the current goes matters. Where the conductors go relative to each other, and to ground, matters. How long and how wide the current carrier traces are matters. What's on the other side of the PCB matters. How close the PCB is to the side of the box matters. How thick the power transistor insulators are matters. How much heat sink goo you use matters. And of course, how hot and how well heat-sunk the entire thing is matters.

Guys who are good at other kinds of electronics will make, as we used to say "self-eating watermelons" when trying their first high power switching power supply. Exploding semiconductors and capacitors; smoking holes where resistors and PCB used to be. Ever seen a diode or a fuse explode? Electrolytic capacitor goo on the ceiling?

If the companies that do this are smart, they'll hire a company that specializes in designing switching power supplies to design their internal power setups, right down to the placement of the mounting bolts. If they're not - well, they're going to have a few field failures.

This is why SMPS are NOT for the faint of heart, and even us experienced techs want to throw them out the friggin' window! Most manufacturers are using out-of-the-box supplies made by aftermarket vendors. there is no grass-roots designing going on. Even the manufacturers who have designed their own are given to multiple revisions. There are more than a few digital mixers out there whose power supplies saw at least two revisions due to poor design and/or inefficiency.

When it comes to power amps of any type, I just DO NOT trust anything other than a brute-force power supply. Give me lotsa iron and big filter caps!

[Bruce]

"Guys who are good at other kinds of electronics will make, as we used to say "self-eating watermelons" when trying their first high power switching power supply. Exploding semiconductors and capacitors; smoking holes where resistors and PCB used to be. Ever seen a diode or a fuse explode? Electrolytic capacitor goo on the ceiling? " Priceless RG !

SMPS I called them "Power to smoke converters " when I used to work on VCR's for a living . Surge and lightning damage , lots of fun .

[888guitars]

Ever try to charge a customer for your 3 hour wait on the phone with Yamaha parts? I put the phone on speaker and start to work on something else.

[Gibsonman63]

That works fine when you are young and don't have to go to the bathroom very often!

[jrfrond]

Ever try to charge a customer for your 3 hour wait on the phone with Yamaha parts? I put the phone on speaker and start to work on something else.

Hang up and call again later. They close for lunch between 12-1pm PST, so don't call then, OR right after.

There are ways to handle phone ordering with manufacturers. You need to learn their quirks and maneuver around them. Unfortunately, not enough manufacturers have on-line parts ordering, OR on-line warranty claim filing.

[Enzo]

If you need to call someone's parts department, arrange to make the call first thing in their morning. If you call in the middle of the day, you will wait in line with everyone else in the world.

[digthisbigcrux]

i was helping a guy, who received at least one call EVERY day from the SAME guy wanting to know if he could hook a speaker cabinet up to his fender twin.

[unparalleled]

Urgent Repair!!!!

This is not too unusual but man, am I cranky!

"Terry" brings me a 110W Traynor head for urgent repair by the weekend for a gig.( this is on a Wednesday I think.)

No problem sir! unless a transformer rewind is required.
He also wants a Quoted price before I have even looked at the amp.
I pointed out that I do not charge for appraisals but quotes are not practical in this kind of work and I would take a look and give him my best estimation.

All the screen resistors had burned holes in the PCB, so I cleaned up the charring with a dremel and fitted wire wound screen resistors spaced up on porcelain beads.
Replaced surrounding blackened components and cleaned everything up.

Then the usual voltage set ups and checks, load tests etc.
Charge was 3 hours @NZ $50.00 and $10 bucks of parts, (dirt cheap repair)

When I gave him the good news he said "what happened to my quote?"

I explained that I had to fix the thing to find all the faults in this case so an estimate was not possible really.

Next thing he shows up with his father (for support) but after explaining to Dad things seemed to be resolved.
Trouble is that "Terry" is actually not a gigging Musician but a student!

They arrange to pay it off at $50.00 a week.
I have not seen them since but have been in contact and received many "Iwill be in this week" and "Sorry I had to spend money to go to Australia" sort of messages.

The date I got the amp in for repair was 18 - 11 - 2009!

Legally I can do nothing because I don't have the guy's full name and address, otherwise I could sell it to cover costs after publishing my intentions in a national Newspaper.

Crazy stuff, this amplifier is worth 2000 bucks here!