PCB vs. point to point

April 30, 2022
 by Paul McGowan

Long ago, when tubes ruled and Bell Labs dreamt of sending electrons through solid materials instead of a vacuum, few consumer audio products had circuit boards.

Though today PCBs (printed circuit boards) are common, back in the 50s they were rare, though hardly unknown. Over 100 years ago in 1903, German inventor, Albert Hanson, came up with the idea of incorporating flat foil conductors by gluing multiple layers of thin metal to an insulating board. It worked, but was hardly a practical solution. Even Thomas Edison experimented with the more common approach of plating conductors throughout the early 1900s. Eventually, credit for the PCB goes to Arthur Berry and Max Schoop who together patented the print-and-etch method in the UK and United States respectively.

What this means is simple. Instead of the earliest attempts of adding to a piece of insulating material the thin strips of copper that would carry the electric currents, today’s PCBs are made by removing all the unwanted copper. You start with a fiberglass sheet (the insulator) that has a layer of copper glued onto it. By means of a printing process, the areas of copper we wish to keep are painted with a type of coating that acid won’t bother. The plate is then immersed in an (essentially) acid bath (ferric chloride) and anything not painted is eaten away. What you’re left with is the conductors to make the circuit work.

Before PCB technology was popularized, our audio circuits were hand-wired in a process known as point-to-point wiring. Tube sockets and capacitors had small eyelets where technicians could wrap wire and then solder the connection. Though cumbersome at best, this point-to-point wiring was a definite plus when it came to sound quality.

Today, of course, it is impossible to wire between points as the circuitry and bits and bobs that make it all work are microscopic.

But, back in the day, it was some really cool techniques.

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37 comments on “PCB vs. point to point”

  1. So happens that I am just in the process of refurbishing / upgrading / turning into a smouldering mass, a pair of Quad II amplifiers. The English point to point wiring system was really neatly loomed with twine and all precise right angle bends which makes some of the wire lengths quite a bit longer than necessary. The more direct American wiring procedure was typically similar to to the above picture. Shock horror but but I am going with the more direct approach with better quality wire. Plus new caps, some valves (tubes) and resistors. Eventually when it is all done I will put some pictures on the “My system forum”. Hope its not a picture of a fire truck.

  2. Today’s picture looks like the proverbial dog’s breakfast, thrown together without care or thought for reliability. However, if point to point wiring was a definite plus when it comes to sound quality does any manufacturer, where cost is no object, still use it?

    Oh, having just posted it would seem that jazznut has already answered my question. Thanks.

    1. It always amuses me how much sighted human beings are
      swayed by visual neatness…even when the priority is audio.
      Also evidenced by a comment about early audio furniture,
      made in a previous Paul’s Posts.

      1. When you think about it, it is funny, perhaps we are somehow preprogrammed? I’d take sound quality over looks and have done in the past when I swapped what I considered my futuristic Quad 66 pre amp for a much more basic passive pre. It’s just that when I look at the picture I think if they couldn’t be bothered to make it neat what else couldn’t they be bothered to do? Then again, beauty is in the eye…..

        1. Especially because it’s internal wiring, it wont be seen anyway.
          Point to point wiring, using the shortest possible lengths of wire,
          will generally always look like unruly spaghetti.
          I’d rather know that the builder made perfect solder joints than
          how (s)he runs the wiring.

      2. Good point and perhaps a topic for a future Paul post/Paul Video. Amazing how often we choose eye candy over what’s inside and at the expense of a tradeoff… a few quick thoughts, choosing a beautiful Italian car over a Lexus…looks vs reliability, a wife or husband you wish you had not married solely because of looks. Perhaps choosing a speaker design for looks vs lower price and affordability. I am NOT trying to stir anything up on this one. The FR30’s are indeed beautiful. Or, stereo choices based on looks vs whats inside of a not so beautiful case , but better performance. Yes, we humans do make some interesting choices when we commit to the purchase…..

  3. I did point to point wiring for simple circuits that I built as an undergrad working in one of the professor’s lab during the summer. This was the late 1960’s, it seems like a long time ago.

  4. Concerning Point to point wiring…
    the phrase(s) burned in my head at the age of 14 while having to qualify to NASA soldering specs every year…. The key to a good solder joint is a good mechanical connection… and the purpose of solder was to prevent corrosion.

    Todays picture would have never passed muster…

    Seems to me circuit boards became the ‘norm’ when the electronics industry moved to solid state and IC’s became the norm along with miniaturization. There’s advantages and disadvantages.

    1. Mike, The group that I did my Ph.D. work in flew experiments on some of the lunar landing missions. They were designed to collect solar particles. NASA’s standards for what was allowed on a lunar mission were exacting and expensive. This was before my time in the group, but the war stories the people who did these experiments told were wild.

  5. Most of the equipment that is true point to point wired does look messy. Most of the equipment that is hand wired looks neat, there is a difference between the two. True point to point wiring has all the caps and resistors at the tube socket radially in almost a Star pattern.

    1. Yes, some hand wired circuits are neatly routed leading to the right angles that were mentioned above. Wires are often bundled ( if cross talk is not a concern ) and zip tied together. The layout starts to resemble that of a PCB.

  6. All my Conrad Johnson amplifiers are hand wired point to point and beautiful to behold. Even better to hear. Their technicians have been there for many years. Hand wiring (and design) is a skill to be learned over time.

    1. I am fortunate to have a c-j GAT S2 and a c-j TEA S3 in my system along with a pair of old P12’s that I no longer use. They are as beautiful inside a they are on the outside.

  7. Why are we concerned by messy point to point wiring? As engineers we look for the elegant solution not just to solve a problem, which is often more difficult. In maths we look for elegant equations, same in chemistry.
    Nature shows us elegant arrangements as in dna and plant structures. Mitchell led a team that eventually designed the Spitfire- a beautiful design. Last, of course, André Lefèbvre with his DS.
    Then there is the FR30. Audio elegance.
    Does elegance matter if it works? Ymmv as someone posts.

  8. If I were building an analog Pease of equipment, and I had a certain thing in mind for it, this is how I would put it together, all depending on what application I wanted to use it in.
    Let’s just say that, I wanted to build a preamp that uses tubes.
    I would use point to point hand wiring to make that happen.
    But now, let’s say that I wanted a preamp dac combo.
    This would be my approach to that.
    I would point to point hand wire the analog cirkets for that.
    And then, build the dac cirkets on a printed cirket board.
    Sure, I would put both parts of the thing in seprid chassisse to keep both cross talk and noise down.
    But that’s how I would do it.

  9. I would think that today with the obvious significant affects of microphonics(as demonstrated by some complex feet designs) that we should be working on wiring methods least affected by microphonics.
    I’ve heard using different feet make more sonic changes than buying a replacement piece by a different manufacturer. And I’ve heard huge differences in the same amp where the differenece was replacing parts of the metal chassis with special plastics. It wasn’t the same amplifier and it was way cleaner and detailed sounding.

  10. I have had a lot of equipment with both circuits and point to point. In my case, the point to point always seemed richer and fuller sounding, and the circuit based sounding more precise. It’s like the extra amount of wire is additive (or subtractive), causing a different sound.

    I’m in the camp of fuller & richer, but I can easily understand liking the other (many of my listening friends do). No right or wrong, just different.

  11. Is it true? Unanimous agreement about some topic in high-end audio regarding subjective sound? Wonderful!

    I learned about point-to-point wiring — and soldering — originally from putting together amateur radio equipment from Heathkits. If point-to-point wiring sounds better, then I like point-to-point wiring!

  12. In junior high, 1965 or thereabouts, my science teacher handed me a project from Scientific American and declared I should do it for the science fair. Sure, I thought, why not. It required a low DC current. I don’t remember much about it, but with my non-existent wiring and soldering “skills” it was not a thing of beauty. An EE who worked with my dad and owned a Radio Shack took one look at it and pronounced it a health hazard, rewiring it himself. Nice guy. The project never quite worked, though the electrical part wasn’t the reason. I didn’t do much soldering again until I started doing Pass diy projects a few years ago after retirement.

  13. All my Conrad Johnson amplifiers are hand wired point to point and beautiful to behold

    I don’t see any photos off the web of point to point wired Conrad Johnson equipment, it’s mostly hand wired but not point to point wired.

    1. You are certainly correct when it comes to the the c-j amps that I have owned over the last twenty years. The PCB’s have thru holes for the tube sockets, capacitors, resistors and the SS devices used in the power supplies. The boards are hand soldered by c-j and the capacitors are firmly held in place with zip ties. I cannot speak to early c-j gear from 1977 to the late 1990’s.

  14. I purchased a Primaluna EVO 400 preamp and it performs way past beyond it’s price point. A rich harmonic transparent presentation can be heard. This in part, is partially due to point to point wiring. It’s a great match with my PSA M-1200 amps.

  15. Maybe a little gearshift here…

    I have a few mid 60s Fender guitar amps that are all point-to-point tube amps famous circuits. (Before the CBS era).
    One of the most elegant point-to-point wired is a newer Fender custom shop amp that is stunning to look at.
    Basically a Fender Bassman circuit, but much cleaner than the old stuff.

  16. In 1962 I built an EICO ST 70 stereo (tube) amplifier from their kit. My soldering skills were not bad due to prior experience, so when it played with a hum I was disappointed. I checked every connection (as noted by Mike above, the mechanical connection is key and I thought the solder was to improve the electrical connection) and re-soldered many. The hum never went away. I have kept it (unused probably since the early 1970s) and a couple of years ago I saw something on line indicating the hum was universal because of a wrong instruction in the manual! It can be fixed, but I think I will leave it for the next owner. And BTW, the point-to-point wiring, as I recall, looks pretty bad when done the way the manual said.

  17. First hifi equipment I owned was a HH Scott LR-88 receiver kit that I assembled during finals freshman year. Never had to study much during high school, so I figured I’d make good use of the reduced classroom time by soldering away the hours. Ended up sounding pretty good with my Dynaco A-25 speakers. First time I ever got a “D” grade in math.

  18. 80% of all printed circuit boards are made in China chiefly do to environmental controls and regulations.
    Potassium cyanide is used in the gold flash process (ENIG surface finish for fine pitch SMT). When cyanide salts are not removed it will interact with white soldermask (white contains titanium dioxide). When heated (reflow soldering) the white mask turns pink. Green mask does not turn color so you will never know how much cyanide reside was left behind.

    1. It depends on whether or not the board has a gold flash on it and if you are soldering on the gold flash. I cannot confirm Tim’s 80% number on how many PCB’s are made in China, but I am sure it is a lot. I think the reason for this is not just looser environmental regulations, but also it is cheaper to have the PCB’s made in China.

      What I am sure of is the entire semiconductor industry requires processes to make the chips, the chip carriers and the PCB’s that are dangerous, hazardous, and not green by any stretch of the imagination. There are plants here in the US that make these things while complying with US regulations. The challenge is competing with the Chinese price.

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