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  • #31
    Deleted due to jumping conclusions.
    Last edited by mozz; 01-02-2019, 10:24 AM.

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    • #32
      Originally posted by mozz View Post
      "Judging by the level of discussion, here are no specialists with the necessary qualification."

      Sorry, you are a troll, we can tell by your level of perfect expertise. If you worded it differently, such as this is why you think a smps is better, we may have took your opinion in a different light. I may not have "qualifications" but I and others have "experience". By your ideology, I have designed and built circuit boards for a major audio manufacturer, so therefore my opinion is the correct one not anyone else's.

      Geeze, explain this one for me. I have seen "engineers" who did not know how to turn on a oscilloscope, and yet another who pushed every single button on a scope to try and get a waveform on the screen. I sat back and laughed.
      We should be mindful that we have visitors from around the world where English is a second language. doctor has proven his worth to be here and has supplied many hard to find items.

      No reason to go off to that road lets get back on track.

      A link to the $5 dollar SMPS supply could be beneficial to the thread.....or not.

      nosaj
      soldering stuff that's broken, breaking stuff that works, Yeah!

      Comment


      • #33
        Words taken out of context are a classic way of substituting concepts.
        I am explaining my position once more.

        1. The reliability of the modern SMPS is not less than reliability of a linear PSU. Repairing of the SMPS is much more sophisticate, but due to its cheapness it is no sense to repair it. It just needs to be replaced with a new one.

        2. There is no sense also to design and make your own SMPS for the aforementioned purpose. Firstly, suitable device can be purchased only for $5.00. The second reason, design of a SMPS is complicate task and it requires corresponding qualification. I am repeating, I do not see among the participants of this discussion members having necessary qualification for design of a SMPS. If someone knows and has experience designing SMPS, please raise your hand.

        I did not write about the lack of qualifications at all.

        3. I personally have not seen "engineers" who did not know how to turn on an oscilloscope. But I familiar with dozens "others" having experience to replace blackened components.

        4. Indeed, English is not my native language (it is only one of three my foreign languages). I concede that I could be misunderstood. But take everything personally and to be offended is a wrong position.
        Last edited by doctor; 01-01-2019, 08:19 PM.

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        • #34
          Originally posted by doctor View Post
          The transformer’s power supply is the day before yesterday design.
          Originally posted by doctor View Post
          This multichannel power supply will be 10 times cheaper and it will take 10 times less time to do it.
          Originally posted by doctor View Post
          In addition, all modern pedals (like other audio equipment) use SMPS.
          Originally posted by doctor View Post
          I just expressed my opinion both as a pro-audio engineer who designed and manufactured a variety of equipment: pedals, amplifiers, analog and digital effects, etc.
          Originally posted by doctor View Post
          I did not mean that someone will develop and manufacture the SMPS here. Judging by the level of discussion, here are no specialists with the necessary qualification.
          Originally posted by doctor View Post
          Words taken out of context are a classic way of substituting concepts.
          Originally posted by doctor View Post
          I did not write about the lack of qualifications at all.
          It would seem that much of what you have to say is inflammatory, dismissive or untrue. No excuses for English not being your first language either. You are curt, judgmental, pontificant and even lied about something you did/said that is clearly in print on the same page you lied about it on.

          I did my best to agree to disagree. I don't think you can do that.

          I don't happen to think that SMPS is a better choice for this application. I stated some good reasons for that. I also don't think that it simplifies the design. I also don't think an appropriate transformer would cost ten times what an equivalent SMPS "module" would for a DIY application.

          There is also the issue of extraneous noise that occurs with incompatibility. Modern or otherwise this has been stated to occur with age in some cases. So "modern" means nothing before some time has proven the performance of any design improvements. Transformers, OTOH, are a known quantity for this circuit.

          Though I do agree that longevity WRT such devices as multi port pedal power supplies for working stage musicians is largely a matter of luck I still believe in the reliability and compatibility of a transformer powered system for this application.

          And indeed there are posters on this thread that can design a suitable SMPS for this circuit. Perhaps it's not the hat they usually wear, but it's not beyond their understanding. It's probably they feel the same as I do about this issue. That is, a transformer for this circuit is not inferior to SMPS and in fact may be superior in a couple of regards.

          I sincerely hope you can take this post at face value and use it to improve your social circumstances not only here, but in other areas of your life too. I'm always glad to be helpful.

          "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

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          • #35
            Hi mike check this pic out since your building one saw this pic and thought it might help.
            http://sluckeyamps.com/misc/pedalboard.jpg
            To anyone else there's interesting stuff on this page, poor mans leslie and other cool things.

            http://sluckeyamps.com/index.htm
            nosaj
            soldering stuff that's broken, breaking stuff that works, Yeah!

            Comment


            • #36
              I would have to say that 'curt, judgemental, and pontificant' is often how non-first language or translations often appear. Especially for technical issues.
              I would beg anyone here who doubts doctor's sincerity to click on his user name and select 'view user posts'. On no occasion has he been less than helpful, and many times more behind the scenes via PM.
              Originally posted by Enzo
              I have a sign in my shop that says, "Never think up reasons not to check something."


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              • #37
                Originally posted by g1 View Post
                I would have to say that 'curt, judgemental, and pontificant' is often how non-first language or translations often appear. Especially for technical issues.
                I would beg anyone here who doubts doctor's sincerity to click on his user name and select 'view user posts'. On no occasion has he been less than helpful, and many times more behind the scenes via PM.
                Ok. I don't have a problem meeting halfway on cultural differences. It's not always a language barrier. More often it's a posture that is inherently offensive between one culture and another. I think I've been moderate. With a hedge that the problem might not be everyone other than the person in question. Not much more to say about that.
                "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


                • #38
                  Originally posted by g1 View Post
                  I would beg anyone here who doubts doctor's sincerity to click on his user name and select 'view user posts'. On no occasion has he been less than helpful, and many times more behind the scenes via PM.
                  Second that! doctor has often supplied rare & obscure schematics here. Although none of them were items I needed, I appreciate his contributions to MEF and consider him a very valuable member.
                  This isn't the future I signed up for.

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                  • #39
                    Yeah, I don't get it.
                    Flogging the Doc is uncalled for.

                    The Doc has been awful helpful supplying obscure documents.

                    From what I read all he said was "welcome to the real world."
                    SMPS is here to stay.

                    Comment


                    • #40
                      Originally posted by Jazz P Bass View Post
                      Yeah, I don't get it.
                      Flogging the Doc is uncalled for.

                      The Doc has been awful helpful supplying obscure documents.

                      From what I read all he said was "welcome to the real world."
                      SMPS is here to stay.
                      I'm not "flogging the doc". I admit to having a little fun with the winky face though. And I'm sorry if I have encouraged further negativity from other members. I've acknowledged that his position is valid. And I honestly hope that any SMPS issues from the earlier power supplies that used them is actually worked out and is now a non issue. It's just too soon to tell really. Short story...

                      A few years ago I was in the market for a new cordless drill driver. my last one was a DeWalt 12V NiCad that was an absolute NAIL of a tool for over fifteen years. In the months prior to purchasing I heard a lot of contractors complaining about the reliability of the batteries in their new Li Ion tools. They would fail prematurely due to charging inconsistencies, sometimes freezing temps were involved (that happens to work trucks here) and the new batteries were expensive. So I went with NiCad again on the premise that it's 50yo tech and caused no problems for me in the past. Here I am a few years later and one of my two NiCad batteries has failed (and I did treat it properly) and all the same contractors are using Li Ion tools without issue. I have serious buyers remorse because my tool is comparably heavy and the crappy batteries they supplied with it are failing anyway. My point:

                      Probably SMPS power supplies have worked out the pedal incompatibility issue? I don't know. My instincts still tell me to go with known, reliable tech. But this has bitten me on the @$$ before and I might be a dinosaur.
                      "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


                      • #41
                        I surfed across these power supplies on ebay a few weeks ago. I didn't expect much for less than $20, but figured I could at least use the steel housing to build something suitable. What I got was a pleasant surprise. It's a nice unit. Much more than I expected. There wasn't much information in the ad. I plugged up to 7 devices into it, and it maintained a constant 8.96v. It's quieter than anything I've ever had. I ordered another for a spare.
                        https://www.ebay.com/itm/Dinosaur-Po...ffb1aa|iid%3A1

                        Here's a gut shot. My only complaint is that I wish the cables had a 90* plug on one end.
                        Click image for larger version

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                        • #42
                          Fr good reasons, more and more pedals include a protection diode in the power path to prevent folks using wallwarts with the "wrong" polarity. Once upon a time, when folks might use any old AC-to-DC adapter, there was a chance they might select one with the wrong polarity (outside ground) and fry the pedal. Then manufacturers started insisting you use THEIR adapters. Eventually folks started powering pedalboards with multi-outlet power "bricks". But once folks were incorporating PNP germanium transistor pedals into their pedalboards, power-brick makers had to include reverse-polarity outputs, which meant there was still a risk of the user running a cable from the "wrong" output to the pedal if they weren't paying attention.

                          So, there is still good reason for pedal manufacturers to include protection against "wrong" power polarity.

                          There are two ways to do so. One is to have a diode to ground, so that anything above the diode's forward voltage goes to ground, leaving the pedal powered by only 500mv or so of the "wrong" voltage (not enough to fry anything). The other is to insert a diode in series with the power supply so that the circuit is never fed anything other than the "right" polarity. The caveat with that method is that it subtracts one diode's worth of voltage. So, if the diode removes a half volt, then the circuit will still get 9v if the power source is 9.6V or thereabouts. Not that the circuit will die if it's less than that. But various circuits may well be tuned/calibrated in anticipation of 9v.

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                          • #43
                            Yeah. Daisy chaining is fine for an all-analog pedalboard...providing all pedals involved have the same power-plug polarity. The one exception might be instances where a pedal uses a charge pump to goose the voltage from 9V to double or triple. IN those instances, there might be some heterodyning of the clock in the charge-pump and the clocks in the switching power supply. That's based on theory, not experience.

                            RG Keen and I have been buddies for over 25 years. As the designer of the One-Spot, he pays very close attention to any complaints or problems that end-users have had, and finds solutions via either production changes to the One-Spot, or posted user advisories.

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                            • #44
                              There's "toast" and there's off-spec.

                              Last year I repaired a buddy's Diamond Memory Lane pedal that had an annoying whine. I corresponded with their tech person, trying to pin down the source of the whine, thinking it was a misadjusted trimmer. It wasn't until I mentioned that the whine didn't start until after about 10-15 minutes of use that he remembered the likely source. He told me that in an early run of the pedals, they had received a shipment of voltage regulators (I think they were 9V) whose heat fin was much thinner than "regulation size" (pardon the pun). He sent me a picture of what it would look like and sure enough, that was the culprit. I pulled it, installed a regulator with normal-thickness heat fin, and the problem went away for good. The pedal used three of the 3-pin voltage regulators, with all three relying on the heat fins to dissipate any heat they might produce. The offending one lacked the heat fin mass to do the job, such that after a little while, it would overheat; not enough to be damaged or damage anything else, but enough to be well off-spec in its performance.

                              The upshot here is that it is not enough to simply add up the current requirements of the pedals used and have that total come out to less than the current rating of the supply. There should be a margin of safety incorporated such that the power supply is not stressed. Keep in mind that most wallwarts and power-bricks are essentially sealed, with no way for heat to escape. Again, the stress may not jeopardize the lifespan of the supply or pedals being powered. But it may result in the power not being on-spec.

                              There is rarely anything wrong with using a PS rated for much more current than the pedals require. That's why one can use a One-Spot - rated for 1.7A - with a pedalboard that only needs 75ma for everything on it.

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                              • #45
                                Thanks to those who say good words about me, but I do not need protection.

                                I have long noticed such a fact. If a professional is told that he does not know something, he will try to study this topic. If these words are heard by a non-professional who has a high opinion of himself (but without big reasons), then he begins to be rude. Because essentially he cannot answer. This is ridiculous and I do not pay attention to personal attacks.
                                I should note that professionalism is not equal to education. I am familiar with great professionals who do not have a higher education. Although higher education is, of course, very desirable. Knowledge cannot be superfluous.

                                Now to the point. Most manufacturers of the audio/electro musical equipment do not produce now linear PSUs/adapters at all, only SMPSUs.
                                There are two points that make life easier for SMPS users. Modern SMPSs have a low level of noise (conductive and radiated emission) and modern devices (including pedals) have a weak susceptibility to external interference (conductive and radiated immunity). All modern audio equipment meets the requirements of the standard EN55103-1 "Electromagnetic compatibility. Product family standard for audio, video, audio-visual and entertainment lighting control apparatus for professional use".

                                Problems may arise with old devices, in the development of which no one even thought about the level of immunity. This problem (if it exists) must be solved precisely for such a device. As a rule, the installation of a ferrite cores on the connecting cables (power, input and output) is sufficient.

                                I am writing this for all those who want to solve such a problem with minimal expenditure of money, labor and time.
                                Last edited by doctor; 01-12-2019, 03:59 PM.

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