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Hi FULLRANGEMAN and all.Well said and I agree 200% with you.Even Audio Note Kits uses PCBs...For me, I only want to buy units with point to point wiring.If you want to keep your equipment for the next 50 years, PCB is definitely not the way to go.The amplifier I bought from Blair at Niteshade Audio is a 100% point to point and I like that.Have a nice day.Guy 13.
Quote: If you want to keep your equipment for the next 50 years, PCB is definitely not the way to go.
Why is that? Have you looked at some old plane avionics?
Blair, Here is another hybrid that I mentioned earlier, a PrimaLuna integrated amplifier. Point-to-point wiring, chassis mounted tube sockets and PCB's for sub-assemblies where it makes more sense. Steve PrimaLuna Dialogue Two integrated I am very very impressed with the build quality of the PrimaLuna. I do think it is made in PRC, or I might be wrong but the clean layout is something worthy of what you see in some really small, high end outfits. Going back to the discussion....PCBs, depending of the quality and grade and as long as it does not use really micro type of transistors...I think they call them surface mounted? that you commonly find in newer, electronic equipment, it can be OK. As long as the parts are well laid out and removable, long term value wise it will be fineNevertheless, more modern and yet cottage like SS amp makers such as Nelson Pass with his FirstWatt outfit clearly shows you that you do not need to have a gazillion small transistors, severely mounted and cramped in a small space to get SOTA sound... in vivid contrast, take the covers out of a late model HT receiver.... they are made for mass production, convenience but not long term ownership. It is as if the makers would like people to either get tired of their equipment or for their equipment to fail, in order for them to make another sale down the road and that is the case. FULLRANGERMAN...I agree with you about all new avionics or automotive stuff relying more and more on chips and lines of program...as always, those kinds of things can and will get corrupted. Too bad that we cannot go back to old autos like, pre-post WWII VWs and other purely mechanical devices.
I can't help but agree with the content of all the posts. Confusing? Well- not really. Wiring/hookup technologies are usually abused. Reasons for abuse:1] To make things look tidy2] To save production costs regardless of repercussionsSome observations from both camps:1] PC's should not have sockets soldered to them that are large2] Wire twisting, looming, etc.. creates extra work and uses more wire than necessary much of the time AND makes repairs more difficult. It is necessary with some circuits, generally not audio. 3] My favorite PC's use surface mount components for at least 95% of the components. A PC board made with SM components that is not plated through for leaded components is not bad to work with and will work very well even with tube audio. 4] P-P runs should be direct. That means wires should go directly from point A to B or at least as close as they can. This method is not as pretty looking as twisting or looming but works the best every time. Scott, Fisher, Conn, Hammond and many others used this approach and so do I. What would think of a "hybrid" wiring approach? Marshall's 9005 1990's EL34 amp did it well. The PC's were well made modules and all sockets were mounted on the chassis. Good ideas are often twisted and made into bad ones. I was thinking that the proper(let's make that ideal) use of both techniques may please the PC and P-P camps.
It is best to keep an open mind and not allow stereotypes to cloud things. If I do anything with PC's, it will be done to benefit the product and not to cheapen it. There are other methods as well, such as turret boards.
I have done thousands of both all hand wired and mostly PCB wired amplifiers over the past sixty years.For a "one off" or very low volume production unit, hand wiring may be useful because the designer need not know how to design a good circuit board and be aware of all the pitfall therein. Also this eliminates the up front PCB design, tooling, and de-bugging costs.However, a well designed PCB circuit insures repeatable, consistent, and very quiet and durable operation. Modern boards have very tough mask layers on top of the circuit traces, so that dust, moisture, and surface contamination is a thing of the past. One writer herein is correct, it is harder to remove and replace tube sockets, but then again its not so easy to do that in hard point to point wired circuits either. The "trick" in removing multi-pin parts from a circuit board is to simply cut all the leads as close to the body of the part to be removed as possible, and then remove the bloody stubs one at a time. A absolutely essential tool for circuit board re-work is wooden toothpicks. We often use these to open solder closed through holes based on the fact that you can't solder to a toothpick. :0 Unless, as my late wife once did when I told her I needed more toothpicks, brought me home a nice box of multi-colored plastic toothpicks. Whoops. Do note that the days of point to point wiring are becoming numbered as more and more high quality parts are become available only as surface mount devices. Its really hard to do point to point bare wire layouts with surface mount parts. I have heard really great audio components both with point to point hand wired and with PC cards, and really lousy ones done both ways too.Back when I was twelve years old and building my first Heathkits, my friends were in awe of the great audio system I put together all by myself. They tried building the amp kits too and I almost always had to fix them, and that is how I got my start in this business. One friend built a nice 20 watt per channel tube amplifier, and it worked, but if you even got near it and barely touched it, it went, Boooooooong!I looked inside. Unfortunately nobody told him to cut the leads of all the resistors and capacitors inside short enough to make tidy point to point connections. He was afraid that cutting a lead might ruin the part, and left all the leads untrimmed. The internal layout was amazing, he actually fit all that extra lead length inside the chassis without anything actually touching or shorting out, however, it was microphonic city. For him, a PCB design would have saved him hours of work.I would suggest that is is really hard to get the degree of circuit shielding with a point to point layout as it is with a good multi-layer circuit board design incorporating a well engineered ground plane and grounding.Hey guys, quick worrying about this and just pay more attention to the music.Best regards,Frank Van Alstine
Quote: If you want to keep your equipment for the next 50 years, PCB is definitely not the way to go.Hi,Your post quoted above, makes remember me of the resale value, looks to me a Point to Point wiring tube amp have better resale value IMO, than a PCB tube amp.Iam fear of PCB power tube amps, PCB looks suited to SolidState amps to me, encapsulated PCB like JeffRowland amps use looks good.
It turns out that a lot of students don't pay attention to the wiring, and most of them looked pretty sloppy. Not bad for a blind man. Ray Bronk
Hi Frank and company,It reminds me when I was in High School. In my electronics class, i built with some assistance here and there from other classmates, a 5 tube radio from Greymart. It was all point to point soldering. I did all the soldering with the ol' Weller soldering gun, which I still possess some 45 years later. Anyhow, I had built it so well, that the Q in the IF Mixer stage was to high. I ended up putting a slightly larger cap in there to reduce the Q. My teacher after it was all done, said This radio is not done. Yes, it is. He plugged it in, and was very surprised to see it was working as expected. He told me this is the neatest built radio I've ever seen. It turns out that a lot of students don't pay attention to the wiring, and most of them looked pretty sloppy. Not bad for a blind man. As far as PCB versus PTP, if properly done, people like Mac'intosh would argue with you because there are a lot of there stuff out there 40 to 50 years and still functioning. My now deceased friend used to hate Conrad Johnson gear. This was in the early .90's. He was always repairing the soldering joints, because the pads would fall off because of the heat. I guess in the long run, it's all in how it is done.As an aside, on a well known preamp kit, that is out there now, wire up the Selector switch directly from the switch to the RCA sockets, and avoid the board traces. The result is a more open sound. Go figure.Ray Bronk
