Higher quality components

[stokes]

PCB's are used for companies to maintain their profit margin,you cant get a machine to assemble a point to point circuit.Yes,some are cheaper than others,but I havent seen one I would call durable,even in a Mesa.

[cminor9]

I thought the whole point of PCBs was durability and consistency

Correct, a robot can assemble 100 PC boards in less time than I can solder in two components onto an eyelet board. And the robot will do the same quality work every time. And so long as you don't bend, stress, overheat, etc that PC board it'll be just fine. In that sense it is durable, and it is certainly cheap. But not durable in the sense that you want to go mucking with it again and again.

PC boards are part of the reason we can get electronics so cheaply these days, and are also part of the reason that once your TV breaks, you don't take it to a TV repair shop. It's often cheaper to replace the thing than to fix it.

[tubeswell]

FWIW when I muck around with PC board mods, I use copper desoldering braid under my iron to soak up all the old solder before attempting to remove the part. It makes resoldering tidier and is also handy for 'cleaning up' dried out flux and other crap off the board (if you sweep it around the board with your iron pressed on top of it). I also keep a wet sponge in an old plastic ice cream tub nearby on the bench and wipe the iron tip on it after every solder to keep it clean. Clean joints function better.

[R.G.]

PCB's are used for companies to maintain their profit margin,you cant get a machine to assemble a point to point circuit.Yes,some are cheaper than others,but I havent seen one I would call durable,even in a Mesa.

I respectfully differ in opinion. While it is true that PCBs can be done cheaply and shoddily in pursuit of profit, they can also be done well, and reliably. If not, why doesn't the military, with an unlimited budget, insist on purely point to point construction?

Actually, if there was enough motive, I think I could program a multiaxis robot to do point to point.

Let's also talk about the reverse. What is the primary determinant of the quality of point to point construction? Yes, it's whose hands did the work, and how skilled those hands were.

IMHO, it is juvenile, naive, and possibly hypocritical to keep chanting the mantra that only point to point can possibly be good construction as though it were fact.

There is one area in which point to point is clearly, measurably far better than PCB construction. That is - and what a surprise! - the ease with which it can be modified. We identified a hitherto unknown disease recently, which goes by the acrynym BUMS. This stands for "Blind Urge to Mod Syndrome", and which appears to destroy both hearing and reason.

There are a number of ways that PCB construction can be done that are clearly, measurably better than point to point. One of the preeminent ones is consistency. Every part and every wire lies in very nearly the same place in every copy. That's something that essentially can't be done by hand wiring.

"Hand wiring" is a better term, as well. There are remarkably few hand wired amps which are actually point to point. Fender tagboards are not point to point. They were hand soldered, and the wiring was hand done, but that ain't point to point.

As a final thought, I believe that it's true that it's possibly to misapply practically any technique and come up with something that's less than the best it could be.

[Enzo]

Amen.

"How many times can someone else tear apart my product and alter it" is not part of reliability. Peavey/Fender/Mesa sell amps to play, not hobby kits.

And I don;t sneer automatically at China. The amps PV and others make in China are specified by the companies. They can be made as cheaply or as sturdily as they want to. The Chinese have men in SPACE for god's sake.

What makes a board cheap? A pc board is a sheet of insulation material such as fiberglass, with a very thin layer of copper glued to it. We can ignore multilayer boards and such. The board has to resist the heat of soldering. You don;t want it breaking down from the construction process. The copper sheet is etched away everywhere you don;t want copper traces and pads. The remaining lines serve as wires, but they are merely glued to the board. How thick that copper is determines how likely it is to tear or break, how easily it spreads soldering heat around. If too much heat is applied, the glue can break down and now your copper trace is flopping around in the breeze. SO boards that are physically sturdy, copper heavy enough to hold up to the abuse, and glue that keeps holding are good qualities in a circuit board.


SOmething to keep in mind when thinking about all the parts in these amps is that the amp is a circuit, not a part list. You can't take a certain characteristic of a part and look up on a list what it will do. For example that plate load resistor that is hissy in your input gain stage would be perfectly happy in the tremolo oscillator circuit. You can set the gain and signal level all through an amp. You can get the same overall gain in one or two stages as in five or six. it is all in what you want to accomplish. But the same parts could be used either way. it is the circuit that matters.

[stokes]

Okay.I stand corrected on the point to point vs hand wired,and my comment on durability was strictly from the point of "modding" or in fact repairing or experimenting with PCB's,which is afterall what this thread is about.I agree with Enzo on the China thing,in this case.Mesa may assemble the amps here,but I would bet many of the parts are made in some asian rim territory.I cant say I agree that the military uses PCB's because they are necessarily better,I think they use them because that is what is the electronic standard today.They arent using guitar amps that users (most of the posters here) want to modify over and over again.They have to buy in quantity,and for a company to get a contract,they have to make a lot and make it fast.PCB's can also save space and make circuits smaller,something they need to address,but most guitar amps that use PCB's are no smaller than a hand wired amp.Brings us back to the fact that amp companies use them because they can be mass produced and keep the profit margin going strong.Yes they are dependable if left to do their job,but like I said,most guys are here to play Dr.Fankenstein on their amps,PCB's arent for them.

[R.G.]

but I would bet many of the parts are made in some asian rim territory.

Of course the parts are made in Asian Rim places. There is a business disease I identify as MBA Disease (M'BAD). The freshly-minted MBA is the demigod of American business for the last couple of decades, and these B-units have been trained in several simple concepts. Some of them are:
- "Stay out of the dog-food business," referring to any business operation where the product is a commodity. This has led American business to actively abandon anything that can be done more cheaply elsewhere.
- "Owe no employee anything except this pay period's check," referring to the perceived disaster of having any ongoing responsibility to employees whatsoever.
- "Manage your investments," referring to the idea that any business line producing less than X% return on total investment per year (or per month!) must be discarded.
When faced with a situation where Asian countries could produce goods which *met the specifications* on their standard product line, American companies responded two ways. Some of them dropped the "jellybean" products entirely, and some of them set up manufacturing in low cost countries. The race to low cost countries is part of why we, all of us, can wear the clothes, drive the cars, use the computers, etc. that we do. Those things would cost vastly more if they were all made in America. Downplaying the quality of Asian goods is as hypocritical as a person delivering a monolog on not eating meat while wearing leather shoes.

I've been involved in sourcing Asian goods for over a decade now. Pretty much, you get what you insist on and pay for. Right now, companies are by and large insisting on the cheapest stuff they can get away with. If you demand quality, you can get quality. Been there, done that.

If you don't like the quality of what American MBAs source from China, talk about the MBAs, not China.

As a final thought, the Chinese and other "low cost countries" will stoop to making things that Americans simply will not - like tubes.

I cant say I agree that the military uses PCB's because they are necessarily better,I think they use them because that is what is the electronic standard today.

This is the same military that buys $100 hammers, yes?

My point was just that if the military wanted point to point, it would get point to point. Yes, it's impractical to do point to point wiring on 144 pin surface mount microprocessors, but practicality never stopped the military. The reason they use PCB is that they CAN get results good enough for their hardly-believable needs with a PCB product, including electronics that will work after living through the 500G accelerations of an artillery shell being fired, massive temperature swings, and the whole rest of the "Mill-Spec" credo. PCBs can do the job, and more importantly, they do it consistently and reliably. The military is accustomed to writing the standards, not following them.

They arent using guitar amps that users (most of the posters here) want to modify over and over again.

True. It's that's "modify over and over again" thing that's the real issue lurking at the bottom of this, not general reliability or Asian quality.

They have to buy in quantity,and for a company to get a contract,they have to make a lot and make it fast.

Everyone depends on buying in quantity. The one-at-a-time electronics buyer is critically, crucially dependent on someone buying in quantities that keep the parts available and sitting in stock on shelves, somewhere. Amp mods are a parasitic industry - it can exist solely because there are enough users of the same parts to keep them being made and stocked for another reason, because amp modding is inherently a one-at-a-time process.

I doubt that any amp modder ever stops to think what a 2W carbon comp resistor would cost if they had to have someone make them one at a time.

But your statement is correct. A modern company making anything, for the military or elsewhere, has to get the product designed, produced, and out the door fast. Pesky MBAs.

PCB's can also save space and make circuits smaller,something they need to address, but most guitar amps that use PCB's are no smaller than a hand wired amp.

I have personally designed, prototyped, built and marketed a guitar amp from initial sketches through CAD drawings, procurement and manufacture in quantity, from soup to nuts. So I have some insight into the amp building biz. The reason guitar amps are not smaller than hand wired amps doesn't have much to do with the size of the electronics. It's driven by other things.

Brings us back to the fact that amp companies use them because they can be mass produced and keep the profit margin going strong.

There is some element of truth there, but there's another less pejoritive way to say that.

The same amp, built from the same parts, can't be built for the same manufacturing cost in the USA. Labor costs too much. As a result, the price to the final buyer will have to go up. There's a lot of commentary about evil manufacturers scheming to keep profits up, and while that does happen, I'm sure, there's another way to look at it.

The MBAs at the amp makers want to keep a profit margin going. It would be great if that was huge, but they'll settle for X%, which varies by industry. In a competitive industry without collusion between makers, the price rapidly settles to a point where X is the going rate for essentially all makers. Unless there is a huge difference in some cost, all makers will use essentially the same process.

The ugly secret lurking in there is that if they can't find some way to make X%, NO ONE will make the amps. They'll all take their investment money and go invest it somewhere where they CAN make X%. This is not evil, this is not conniving, scheming, soak-the-customer practice. It's human nature, abetted by MBA'D. If you can do either of two jobs, one earning you $10 an hour, and one earning you $50 an hour, and neither is particularly objectionable, neither is the love-of-you-life calling, just different, which do you choose? Businesses are faced with this all the time. Want to invest in making buggy whips? Sure, if you're a custom maker and can command artisan prices. Probably not if you have to decide what to put $10M of investment money into next year.

In societies with free choice *no* *one* chooses *not* to keep the profit margins going strong. We might wish for people to give us stuff which is made for lower prices than we would choose to accept for our labor, but that is not a stable condition in the real world. Speaking of which, many Chinese laborers have found that after they have learned a skill, they can market their skill to the next factory over for more money. After each major holiday in southern China, factories typically have to replace 20-30% of their work force for losses to other factories which will pay them a little more. So some Chinese companies are now out-sourcing labor to even lower-cost places like Vietnam.

If a China is available to make amps, for instance, at a savings of 75% of the labor cost in an amp, then when the first amp maker starts manufacturing there and achieves an obscene profit margin, the others must immediately follow or go out of business. And in a short time, every maker is making them there. Sound familiar? In American manufacturing, there are two kinds of companies: those that are manufacturing primarily offshore to avoid high labor costs, and those that are going broke.

Most amp buyers don't mod amps. Those that do are presumably mature enough to realize that they are taking their chances in an area that most guitar amp owners, much less most people, choose not to play in. As such, they ought to realize that to make a good modded amp, they will have to pay the price of getting a good basis for their mods. That means either a) an older amp which has easily modifiable construction or a new amp with easily modifiable construction. There are many of these last, those being the boutique amps which are made one at a time by a hand-wirer.

Eh? Those boutique amps are too expensive to buy just to modify? What a surprise!

As a final note, I know one company that did the obvious thing. They sent a skilled hand-wirer to south China to teach and oversee production of hand-wired guitar amps there. The amps worked, sounded good, but could not be sold for enough of a premium over PCB based amps to make it worth it because they, too, were "made in China".

The Chinese hand wiring was of good quality, but it required the teacher/overseer to be there watching quality all the time. Oddly enough, just like getting good quality production anywhere. The venture fell apart when the guy who had to live and work in south China got tired of it and came home.

Yes they are dependable if left to do their job,but like I said,most guys are here to play Dr.Fankenstein on their amps,PCB's arent for them.

And I agree with that. For the person whose aim is to tinker with their amp, PCBs are a trickier medium to do it with. It's almost like there were unseen laws of economics forcing the conditions that if you want to do something outside the low costs of high volume production, you have to pay the freight to do it.

[BK-Amps]

..Mesa uses relatively inexpensive PCBs which makes experimentaiton a nightmare....BK

My intention on that comment was to point out Mesa boards (vs. many other manufacturers) don't particularly take well to mods. There are many other manufacturers that overbuild their PCB making them more mod friendly. I happen to use PCBs in my own designs, but I don't use 1/2oz copper traces, half sized pads, and the thinnest FR4 the fabricator offers. Holding that solder wick under your iron for a split second too long will lift the trace on a newer Mesa board.

BK

[Froumy]

Would this be the BUMS support group?

Enjoyed the Mba,too.

Guess we all agree that if you have BUMS, a PC board isn't necessarily your best friend. For a really severe case of BUMS, I recommend a turret board....

And to re-answer the initial question, proceed with caution, if decide to go ahead with it, and it may or may not improve the tone.

[6267]

You kids with your boards. If it can't be tied to tube sockets, pots, or chassis bolts I say it's not worth including

[Bruce / Mission Amps]

A PCB tale

For what it's worth...
I never cared for PCBs much at all... more importantly the really cheap ass, clock radio PCBs found in many inexpensive products from the Asian rim. Guitar amps, PA amps and preamps included.

However, about three or four years ago I got talked into trying some MIL spec PCBs, made up for a little 10 watt vacuum tube amp project (SE 6L6GC two 12AX7s with an extra FET preamp stage and trem, etc...
I told them I wanted a really good PCB. And they supplied it.
I wasn't cheap at all, but it still cost less then the total cost of my laser cut, handmade G10 Eyelet boards when also figuring a laborer at $10.00/hr to pound eyelets.
After the project was built out... I had a couple/three PCBs left over with no chassis left.
Well, I didn't know what to do with these so I tossed them aside and ended up using them as tools.... cabinet scrapers, glue spreaders and believe it or not, a ceramic tile scraper and a grout float!!

About a year and a half ago I had a friend of mine beg me to build (actually "her" for him) one of these SE amps and fit it into a generic chassis.
All I could find was the ceramic tile grouting/scraper PCB laying in an old bucket in my garage filled with small hand tools, broken tile chips etc.
Of course it was trashed out... but amazingly, after a considerable amount of time I was able to clean it off with solvents, a Scotch Brite pad and after cleaning out all the plated through holes (yikes, it meant a small pin vice and tiny drill bit)... , I found that there was ... no damage to any trace, plated through holes or lands on either side, NONE, NADA, even though it was dull as concrete and there wasn't a square edge on it anywhere!
I could see no damage, with respect to full functionality, anywhere.
And after soldering parts in, hooking up the wires to the sockets, pots and trannys et al... held my breath, fired it up and BINGO.. a working amp.

That pretty much changed my mind on what a really well made PCB can be like and I, for one, would consider using this type of PCB in any amp, if the boutique amp market wasn't so negatively biased towards them.

[Steve Conner]

Ah, the golden age of electronics, when a Heathkit TV kit was actually cheaper than a ready-made TV.

[stokes]

I would bet if the amp manufacturers would use the PCB's described by Bruce,we wouldnt have discussions about how PCB's suck.

[R.G.]

I would bet if the amp manufacturers would use the PCB's described by Bruce,we wouldnt have discussions about how PCB's suck.

I think you're right. I was always bad at keeping secrets, so back in May of 2000, I wrote my ideas on how to do PCBs for tube amps right.

I believe the list is still pretty close to correct. I used all that stuff in our run of amps, and it seems to have worked pretty well. The biggest issue we ran into is that some through hole parts don't have leads long enough to go through 1/8" thick glass-epoxy.

Otherwise, it's worked out pretty well.

[stokes]

I think you're right. I was always bad at keeping secrets, so back in May of 2000, I wrote my ideas on how to do PCBs for tube amps right.

I believe the list is still pretty close to correct. I used all that stuff in our run of amps, and it seems to have worked pretty well. The biggest issue we ran into is that some through hole parts don't have leads long enough to go through 1/8" thick glass-epoxy.

Otherwise, it's worked out pretty well.

Very good piece on construction there.I saw the couple of articles you did in Premier Guitar,R.G. are you going to continue with them?It is probably the best guitar mag I've seen,and your writings are definately an asset.Hope it works out for you.