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  • #31
    Originally posted by RudeBoy View Post
    It is one ounce copper but I think they only provide 1/16 inch board thickness so I have been reluctant to try them for a tube design. Maybe it would be okay, dunno.
    I have a strong opinion about that.

    For use in the high-vibration environment of a guitar amplifier, you need to mechanically support 1/16th inch PCB no further than every 2" to ensure it does not flex.

    I would recommend 0.093" thick PCB, not 0.062" (1/16th). That lets you run support points out to about 3-4".

    I would recommend plating up to a minimum of two ounce copper, and also designing for equal % coverage of top and bottom layers, as well as making straight runs of copper no longer than about 2" before taking a corner, whether the trace run needs it or not.

    The most complex board I worked on was about 23" by 27" and had 20 layers. I've heard that an TI they once built 24 layer boards. This was back in the day of 16 pin TTL logic, and they brick-walled both sides of the board with chips. They soldered them by putting rosin-core solder ringlets on each pin of each IC, then dipping the whole board in boiling peanut oil to reflow the solder on each pin.

    Yield was about 5% on a good day.
    Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

    Oh, wait! That sounds familiar, somehow.

    Comment


    • #32
      It is one ounce copper but I think they only provide 1/16 inch board thickness so I have been reluctant to try them for a tube design. Maybe it would be okay, dunno.
      I also use BatchPCB, and for large designs, you'll get hosed on the price compared to going to Gold Phoenix directly. They have the option of 2oz copper and thicker boards if I remember correctly.
      -Mike

      Comment


      • #33
        Originally posted by mooreamps View Post
        Then I would take issue with that.. I don't need to pretend to be patriotic, not with three rows of ribbons on my US Navy Dress Blue Uniform, including Expeditionary for being in country in a combat zone during time of war.. Also, cost of living in the US is higher, especially living here in the Silicon Valley.. If people want my expertise, they will pay me for it...
        That is fine as a personal statement of position. I don't doubt that you are genuinely patriotic, and proud of it. You personally may be one of the exceptions to what is admittedly a very broad brush I used.

        However, let's look at the pieces of that statement as well.
        I don't need to pretend to be patriotic, not with three rows of ribbons on my US Navy Dress Blue Uniform, including Expeditionary for being in country in a combat zone during time of war..
        For which I genuinely thank you.

        However, that's got nothing to do with:
        Also, cost of living in the US is higher, especially living here in the Silicon Valley..
        Living in silicon valley is a choice you make. It's important to accept that none of us are entitled to any economic *anything* because of where we live. You may feel that your work ought to be worth more because of where you live, or you may be able to get more for your primary work product - which is not building amps, or you wouldn't need to be a "rocket scientist" - but it's got nothing to do with what you feel you ought to get for building amps.

        If people want my expertise, they will pay me for it...
        That is true. The question is - is your expertise sufficiently greater than some other amp builder's expertise to convince a well-informed buyer to buy yours and not his? People are free to buy or not buy your expertise, and you are free to sell your expertise at the price they're willing to pay or not as you choose.

        Anecdotes seem to matter to you more than principles, so I'll give you an anecdote to encourage some thinking. I happen to personally know the guy who modifies and takes care of Eric Johnson's amplifiers. He builds custom amps too. He's spent his entire adult life repairing and building tube amps.
        (a) Is his expertise more or less than yours? Or is it possible to say?
        (b) Is his time worth more or less than yours?

        To sum up, let me put this a different way.

        I consider being willing to defend your country to be a minimum acceptable condition. Failing that test means that your country will not exist very long. I'm happy you meet that minimal test.

        However, that's not an economic issue. It's a survival issue. I deeply resent people who imply that I'm more or less patriotic because I buy or don't buy their snake oil when the only thing at stake is whether they make a profit. Frankly, I consider falling for "buy my stuff because it shows you're patriotic" advertising to be the worst kind of susceptibility to being defrauded. My patriotism does not depend on whether I buy someone's dubious claims about country. Does yours?

        Economics is not patriotism. Economics is more fundamental than country. Countries can be fully defended with stout hearted patriots and be swept out of existence by economic forces. And have. Worse yet, patriotism can be used to mask economic failure, and usually is when a country's leaders have economic problems.

        Think about it. You can lead a horse to water but you can't make him think.
        Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

        Oh, wait! That sounds familiar, somehow.

        Comment


        • #34
          Originally posted by R.G. View Post
          I deeply resent people who imply that I'm more or less patriotic because I buy or don't buy their snake oil when the only thing at stake is whether they make a profit. Frankly, I consider falling for "buy my stuff because it shows you're patriotic" advertising to be the worst kind of susceptibility to being defrauded. My patriotism does not depend on whether I buy someone's dubious claims about country. Does yours?

          Economics is not patriotism. Economics is more fundamental than country. Countries can be fully defended with stout hearted patriots and be swept out of existence by economic forces. And have. Worse yet, patriotism can be used to mask economic failure, and usually is when a country's leaders have economic problems.
          This is one of the most eloquent statements on the issue I have read. Brilliant. I may even sig a piece of it.
          "Take two placebos, works twice as well." Enzo

          "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

          "If you're not interested in opinions and the experience of others, why even start a thread?
          You can't just expect consent." Helmholtz

          Comment


          • #35
            I want to back Steve and R.G.'s inclination to have the circuit and layout done by the same designer when possible. I'm a novice with respect to PCB's but did design an amp for someone who is using them for production. My prototypes were on eyelet board but I took great pains to design them so that the final PCB layout would be the same. It really wasn't that hard and I think for anyone novice to PCB's this is an easy way to go and the end product sounds and performs just the same as the hand wired prototypes.

            JM2C
            "Take two placebos, works twice as well." Enzo

            "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

            "If you're not interested in opinions and the experience of others, why even start a thread?
            You can't just expect consent." Helmholtz

            Comment


            • #36
              Hmmmm...??? Maybe I associate qaulity with certain (that's the operative word) American and Canadian made products because I go searching out those products (amps, guitars, home stereos, some tools, furniture, clothing when possible, and a few other things).

              Chinese manufacturing has indeed changed, and for the better, and I know that if I buy something, and it turns out to be junk, the decision to make it improperly didn't likely come from the foreman on the factory floor in China, it came from the head office on Streetsville USA/Canada. Having said that, I try to buy as much as possible from companies that make the product here, or in the US. I don't mind paying more for guitars and amps that are made here, part nostolgia, for sure. But also the line from the work bench in Michael Swart's work shop to my living room is pretty direct. If I call his shop, he picks up the bloody phone! Mesa, is a little more complicated, but I can still call and deal with people at the factory where the amp was made. Randal Smith might not pick up, but there are a few customer service folks to deal with your questions. That means something too. For me, this is not all about partriotism, as I believe that can be measured many ways, and no one action is necessarily the defining element.

              One thing is for sure, this has been a very interesting thread, and I have to say that I have fewer doubts about PCB than when I first asked the question. For some reason though, I still shudder at the thought of an amp, like the VOX AC15 being made with MDF and PCB!! And I know there is no way to rationalize that prejudice becasue it's a great sounding amp for just over $500, and if the number of users on tdpri, TGP are any indication, they sell a lot of them. How many more would the sell if it was available with a birch ply or pine cab and hand wired either with PTP or turret board?

              Comment


              • #37
                ...as well as making straight runs of copper no longer than about 2" before taking a corner, whether the trace run needs it or not.
                Please elaborate a little bit more on that. Plenty of amps have much longer straight (and parallel) traces than that.

                Comment


                • #38
                  Originally posted by R.G. View Post
                  That is fine as a personal statement of position. I don't doubt that you are genuinely patriotic, and proud of it. You personally may be one of the exceptions to what is admittedly a very broad brush I used.

                  However, let's look at the pieces of that statement as well.

                  For which I genuinely thank you.

                  However, that's got nothing to do with:

                  Living in silicon valley is a choice you make. It's important to accept that none of us are entitled to any economic *anything* because of where we live. You may feel that your work ought to be worth more because of where you live, or you may be able to get more for your primary work product - which is not building amps, or you wouldn't need to be a "rocket scientist" - but it's got nothing to do with what you feel you ought to get for building amps.


                  That is true. The question is - is your expertise sufficiently greater than some other amp builder's expertise to convince a well-informed buyer to buy yours and not his? People are free to buy or not buy your expertise, and you are free to sell your expertise at the price they're willing to pay or not as you choose.

                  Anecdotes seem to matter to you more than principles, so I'll give you an anecdote to encourage some thinking. I happen to personally know the guy who modifies and takes care of Eric Johnson's amplifiers. He builds custom amps too. He's spent his entire adult life repairing and building tube amps.
                  (a) Is his expertise more or less than yours? Or is it possible to say?
                  (b) Is his time worth more or less than yours?

                  To sum up, let me put this a different way.

                  I consider being willing to defend your country to be a minimum acceptable condition. Failing that test means that your country will not exist very long. I'm happy you meet that minimal test.

                  However, that's not an economic issue. It's a survival issue. I deeply resent people who imply that I'm more or less patriotic because I buy or don't buy their snake oil when the only thing at stake is whether they make a profit. Frankly, I consider falling for "buy my stuff because it shows you're patriotic" advertising to be the worst kind of susceptibility to being defrauded. My patriotism does not depend on whether I buy someone's dubious claims about country. Does yours?

                  Economics is not patriotism. Economics is more fundamental than country. Countries can be fully defended with stout hearted patriots and be swept out of existence by economic forces. And have. Worse yet, patriotism can be used to mask economic failure, and usually is when a country's leaders have economic problems.

                  Think about it. You can lead a horse to water but you can't make him think.
                  Don't get me wrong... I should not imply service in the military or implied expertise in my day job as sole requirements for designing and building amplifiers... Maybe it should simply imply that some mistakes I don't make, like for example using a too thin of hook-wire for carrying power tube filament current ; or specing a 1/4 watt resistor when a 1/2 watt or 1 watt would be more appropriate. But if someone tells me my equipment sounds thin or tinney or scratchy, that's fine, I'll go back and figure out how to make the appropriate corrections... .. . However, on the other hand, no it's not rocket science and learning how to build a quality product should not be that hard given if one has the attention to detail required to do the job correctly. . . . .

                  -g
                  ______________________________________
                  Gary Moore
                  Moore Amplifiication
                  mooreamps@hotmail.com

                  Comment


                  • #39
                    Originally posted by GainFreak View Post
                    Please elaborate a little bit more on that. Plenty of amps have much longer straight (and parallel) traces than that.
                    Not to mention that you see it in turret and eyelet contruction MORE than with PCB amps (ribbon cable not considered)
                    "Take two placebos, works twice as well." Enzo

                    "Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas

                    "If you're not interested in opinions and the experience of others, why even start a thread?
                    You can't just expect consent." Helmholtz

                    Comment


                    • #40
                      In part, the following reply to a question that I asked on the gear page is what led me to start this thread here. It was sent to me as a private message, and he asked me to keep it annonymous. He is a VERY well known manufacturer of well made, high quality amps that incorporate both PCB and some hand wiring, like Mesa. I asked him: "can you comment on Mesa (LSS) PCB's?"

                      --------------------------------------------------------------------------------
                      His response:

                      "Honestly, they are tolerable quality at best. I find the traces very thin, they qare extremely densely populated, so servicing is very difficult, and in some cases the components heat up and de-solder themselves. Since I also run a repair shop in our company, we see lots of amp of all kinds for repair. The Mesas are the most complex circuits, and least desirable ones to work on IMHO. Wish I could be more positive, but that's my honest opinion. It still amazes me that they sell them as inexpensively as they do, but clearly you pay a price. I understand the return and repair ratio can be from 20 to 30% of units shipped....kindly keep to yourself."

                      Any thoughts? Don't all of these "Hand Made" "Boutique" American amps that use PCB and some hand wiring fall into this "assessment"? Bugera, Mesa, Freyette, Fuchs???

                      Comment


                      • #41
                        Originally posted by Steve Conner View Post
                        Well, Bugera are Behringer's guitar amp brand. They are most definitely farmed out to China and made of cheap parts, like all the other Behringer stuff.
                        Actually Steve, Behringer is totally autonomous and makes EVERYTHING in their ISO-rated Behringer City factory in China, and I do mean EVERYTHING, right down to having their own forests that supply the wood and pulp for cabinetry and speaker cones. They might actually be one of the very few companies in our industry that has total QC over everything they do.
                        John R. Frondelli
                        dBm Pro Audio Services, New York, NY

                        "Mediocre is the new 'Good' "

                        Comment


                        • #42
                          Jared: Of course he's going to say that. He wants you to buy one of his instead of a Mesa. If you go to a Ford dealer to buy a car, he's hardly going to say, well to be honest Hondas are pretty damn good. I'm not accusing him of lying: the best car salesmen actually believe the crap they spout.

                          John: Yes, I know. It's the audio electronic equivalent of the mystery meat that chicken nuggets are made from. I'm eagerly awaiting their new guitar speaker line, the Soylent Greenbacks.

                          OK, so I own four pieces of Behringer kit and they all work fine. And my booteek Focusrite mic pre, which didn't. It blew up and cratered its power supply board.
                          Last edited by Steve Conner; 01-30-2011, 06:54 PM.
                          "Enzo, I see that you replied parasitic oscillations. Is that a hypothesis? Or is that your amazing metal band I should check out?"

                          Comment


                          • #43
                            That's funny! If they have run out of materials, they could always try making speakers and amps out of people - who don't play of course!

                            Comment


                            • #44
                              Originally posted by Chuck H View Post
                              ...I think for anyone novice to PCB's this is an easy way to go and the end product sounds and performs just the same as the hand wired prototypes.
                              I agree. Getting the positions of the conductors exactly the same every time is a critical step in getting it to work first time, every time. Good thinking!

                              Originally posted by Jared Purdy
                              Chinese manufacturing has indeed changed, and for the better, and I know that if I buy something, and it turns out to be junk, the decision to make it improperly didn't likely come from the foreman on the factory floor in China, it came from the head office on Streetsville USA/Canada.
                              I just got back from NAMM, where I demo'd our stuff to dealers and visitors. "Is this made in the USA?" was a very common question. I answered it this way:
                              "No. We make all of our products in China. We do this deliberately, and with a lot of care and thought. If you want the cheapest stuff you can get, the Chinese will sell it to you. If you demand quality, you can get it from China the same way you get it here: you do good design, and work continuously with manufacturing to keep the quality high. And you keep working on it. And you keep working on it.

                              We've been working with the same factory in China for over a decade. They know the quality we demand, know we will pay a fair price for quality, and that we will work with them to solve any quality issues."

                              Quality is not a one night stand. It's a long term relationship. I have some pride in the fact that we get good quality at good prices. But it's a long term job, not a rim shot.
                              Originally posted by Jared Purdy
                              Having said that, I try to buy as much as possible from companies that make the product here, or in the US. I don't mind paying more for guitars and amps that are made here, part nostolgia, for sure. But also the line from the work bench in Michael Swart's work shop to my living room is pretty direct. If I call his shop, he picks up the bloody phone! Mesa, is a little more complicated, but I can still call and deal with people at the factory where the amp was made. Randal Smith might not pick up, but there are a few customer service folks to deal with your questions. That means something too. For me, this is not all about partriotism, as I believe that can be measured many ways, and no one action is necessarily the defining element.
                              That's a good and valid argument for your preferences. We're quite sensitive about the support we give our customers, and I agree with you on the need for it. We may manufacture in China, but we answer the phone, replace any defective units, provide reasonable priced repairs for items out of warranty, and you can get the owner own the line by request. Or me. Service is also a relationship.

                              The idea that "not USA"= junk (or Canada, or Germany, or whatever) occurs when businessmen defend their profits by disparaging the source. If the quality and support are good, you don't have to talk loudly about where it came from. It doesn't matter. If the quality and service are bad... well, draw your own conclusions.

                              Originally posted by Chuck H
                              Originally posted by GainFreak
                              Please elaborate a little bit more on that. Plenty of amps have much longer straight (and parallel) traces than that.
                              Not to mention that you see it in turret and eyelet contruction MORE than with PCB amps (ribbon cable not considered)
                              It's a mechanical issue. The thermal coefficient of expansion of copper and glass-epoxy are different. The longer a parallel run of copper and glass-epoxy, the more stress temperature changes put on the bond between the PCB stock and the copper trace. PCBs with unequal top and bottom side coverage tend to bend with large temperature changes, just like, and for the same reasons as, bimetallic thermometers and thermostats. Bending the trace ever so often lets the trace have some bending compliance that straight runs don't have. It doesn't have to be much. Just some.

                              Wider traces have less problem with the copper delaminating, as there is more surface area of adhesive to the PCB in a given length of run. Thicker copper makes the copper stronger and needs a wider trace to avoid overstressing the adhesive.

                              It's not an issue in hand wiring or ribbon cables.

                              A long, thin trace doesn't automatically fail, or even mostly fail. But if you have the space, a couple of wiggles will ensure that it almost never does.

                              Just one of those things you pick up over time.

                              Originally posted by mooreamps
                              Don't get me wrong... I should not imply service in the military or implied expertise in my day job as sole requirements for designing and building amplifiers...
                              Good. We agree. Patriotism is not a suitable basis for any given level of payment, price or profit. On the other hand, experience and training is. Where one gets the experience and training makes *no* difference in the finished product, only the quality of the training and attention to the execution. So logically, we agree that patriotism is not a basis for price. Glad we cleared that one up.

                              Originally posted by jrfrond
                              Behringer is totally autonomous and makes EVERYTHING in their ISO-rated Behringer City factory in China,
                              Chinese law requires that a manufacturer setting up shop in China set up the ownership as a 51% Chinese owned company. Behringer cannot own it all, by law.

                              Originally posted by jrfrond
                              They might actually be one of the very few companies in our industry that has total QC over everything they do.
                              Total QC control implies total QC responsibility. If they have total control, it ought to be very, very good, yes? Does Behringer customer experience bear out that?
                              Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

                              Oh, wait! That sounds familiar, somehow.

                              Comment


                              • #45
                                Great responce, thank's for taking the time. I'm curious to know what amp co. you work for??!! You can PM me if you like!

                                So, where does a compant like VOX fit into this senario? A few years ago they released the latest incarnation of the AC15 (not PTP) with reverb and trem, and there were a mountain of problems with that amp. Made in China. I'm not sure what ehnumbers are for expectable defects, but they were over the top. rom ahat I understand, they have fixed it, and the latest AC15 PCB, MDF, reverb and trem incarnation sells like hot cakes, is made extremely well, and sounds amazing for $550 and change. What happened?

                                Comment

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