PCB evolution, you may have thought it was better by now...

Some old Dumble interviews have him expressing that electrons can survive in the vacuum of space of a tube better than they do in the crystal lattice of a transistor, in regards to an amp he built using a FET transistor for its input...

This makes total sense to me. Through wire / semi-conductor material, most electrons travel along the surface. It makes sense to me that there would be more friction and opposing forces encountered on the surface of a wire or through "semi-conductor" material vs a vacuum tube where grids and suppressors are necessary to keep all the electrons from slamming the anode plate all at once.
 
I'm trying to stay out of this and go back to designing PCBs for satellites. No way I'm PTP wiring a digital control system, I'm guessing Fender feels that way about their modeling amp (as does Fractal, Line 6, Boss, etc...). It's a matter of using the right tools for the right job, simple hand wired PTP amps are a thing of beauty, once more functions are added, complex switching, MIDI, digital effects, etc... hand wiring is not feasible, and would be introducing more potential points of failure.
 
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I'm trying to stay out of this and go back to designing PCBs for satellites. No way I'm PTP wiring a digital control system, I'm guessing Fender feels that way about their modeling amp (as does Fractal, Line 6, Boss, etc...). It's a matter of using the right tools for the right job, simple hand wired PTP amps are a thing of beauty, once more functions are added, complex switching, MIDI, digital effects, etc... hand wiring is not feasible, and would be introducing more potential points of failure.

100% agree that at some point PTP is no longer an option.
 
I much prefer turret board (what some call "PTP") than PCB, because it is extremely easy to solder/desolder components in said turrets.

To borrow some corporate tool phrases, turret board construction is "robust" and "scalable".

PCB, not so much.

PCB is typically smaller scale as well (not as small as surface mount, but yeah).
 
Some need to simply stay away from the adult section of the forum; where experienced adults talk about experienced adult things.

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True PTP and turret/eyelet board construction are often commingled into the same acronym. True PTP is a very different beast than turret board, which is a different beast than eyelet board construction. True PTP is literally where the leads of the resistors and the capacitors connect directly to the other components and tag boards are used to combine or delineate a circuit path from or to multiple other components. True PTP is rather messy and has the shortest theoretical signal path since wires are not often used in the layout to connect things. The layout of True PTP looks more like a schematic realized in 3-D.

Eyelet board construction is an in-between of the two other build styles. Eyelet boards can be laid out exactly like turret boards, but stacking components is difficult to do, and depending on the medium used to make the eyelet board, other problems can arise. Most eyelet boards are made on a thin sheet of some non-conductive cardboard soaked in wax or other thin material. The problem with eyelet boards made from wax-dipped cardboard is that moisture ingress into the board can cause conductivity between circuit paths that were never meant to see each other. Secondly is that the eyelet board is not very rigid and can warp or move over years of heat cycles. This warping can cause undue stress on parts that can cause them to fail, especially if you don't leave enough lead on the part to account for movement.

I would account eyelet board construction as being my least favorite way to build an amp, at least in the conventional way. In more recent years, some vendors have used eyelet boards made of fiberglass ( ala Dr. Z and recently Morgan amps ). Eyelets are faster to build than turret boards because they are easier to press and easier to wire to. This is not without other consequences and compromises. Eyelets are prone to losing bottom-loaded components and connecting wires. This is because the thin eyelet can only hold so much solder before it drips out the bottom, often allowing anything hidden on the bottom to fall out as well. Eyelet board construction is best done with ALL top-mounted circuitry, which can take from the aesthetic and be messier looking.

Turret board construction is the most robust, repairable, and clean-looking way to build an amp. The compromise is time and wire length vs that of true PTP construction. Turrets take a fair bit of work to press, or hammer in, and to boot you often have to custom fit each component for proper military-spec wiring. This adds hours to the build time on more complicated amp topologies. From an objective standpoint, the idea in amp building is to use the shortest signal path you can, with as few wires or components crossing paths. This is impossible to do no matter which build technology you go with, but PTP usually wins in the short leads and compactness department. Turret board construction adds greatly to repairability and to me, is the best compromise.
 
I much prefer turret board (what some call "PTP") than PCB, because it is extremely easy to solder/desolder components in said turrets.

To borrow some corporate tool phrases, turret board construction is "robust" and "scalable".

PCB, not so much.

PCB is typically smaller scale as well (not as small as surface mount, but yeah).

Actually, I think the larger factor is scale of production. Turret board would be for small runs, and isn't 'scalable' for large production. PCB is for when you've got to make thousands and thousands with consistency.
 
It might be a disappointing state of affairs if you're really into the whole "admiration of construction/layout of amps" thing, (which I get but don't really care about myself) but it's the most convenient way to fix a modern, large production 3-4 Channel amp with complex switching, features, perhaps midi etc. Just swap out the bad PCB for a new one ..like when your LCD TV or washing machine goes bad, next thing you know you're ready to rock again :bigthumb:

Quick, super easy and (as far as actual cost of repair goes..ie. there's practically no labor, diagnosing stuff w/ chopsticks etc involved) ...cheap..
 
You may think that it would be cheaper to fix a PCB board than to just replace a few parts on a turret board, but consider this. Let's say a motherboard ( the main board for your amp per see ) costs $100 to replace, and you spend $150 in labor between the bench fee and labor/hr. You also have to wait for that board to ship, if even available. So not only does it still cost significant money to fix, but you have to wait a week or several weeks for the part to arrive. Let's say that your prized amp is made with turret board construction, most techs can fix it the day they get it on their bench unless by chance they don't have a part in stock. Often times there is no need to even remove the turret board, so time is shortened significantly for any repair at all. Single resistors and caps cost between $1 and $20 depending on the type. So for nearly half the money ( 90% of which is in labor at this point ), you can probably get your amp back in just a couple of days as opposed to weeks waiting for PCB boards to arrive.

I totally understand that many artists could care less about what is inside the box that is their amp, so long as it works and sounds good. There are just as many who fawn about the quality of their amps build, how it looks, and its perceived value in a generation or two. Vintage amps today cost what they do because there is a large enough market of people that will pay that kind of money for an old amp that likely needs repair, or will very soon. The best amps made today will be what is the new vintage 20-50 years from now.

Many years ago, all I cared about was if it sound good and did it work. As I started building amps, I realized how much energy, time, and effort goes into making them. I didn't just want the amp to work, it also needed to be a piece of art, otherwise what is the point? I saw how many DIY builds were literally just slapped together, how many people were asking on forums for help to fix their hot mess of an amp because they just didn't take the time to make it clean, and didn't do enough research into how their purposed circuit would work. I realized I had a talent that went beyond simply building an amp and when I hit the power switch everything just works. For me, it matters how it's built beyond just the circuit, beyond how it sounds, and beyond what someone else thinks of it. It has to be the best you can possibly get, that is my standard. Hence why I write books about it, research it and present my arguments for it. No one on this forum is going to buy my amps, I have nothing to sell, but if you come across one of my amps, it will nab all your attention.

As mentioned before by me and others, I am not knocking PCB construction. Tit for tat, it is every bit as good from all technical standpoints EXCEPT for repairability, artistry, and perceived value. There is no replacement for PCB designs when you need four channels, two or three FX loops, switching, midi control, and tube sensing circuits. The world's most sought-after and expensive amps don't have those features though. For some reason, single-channel, or low channel count amps tend to pull the highest dollar, regardless of construction type. Not sure why? I can say that for me, repairability is a huge deal. When I buy an amp, I want it to last a long time, and when it needs repair, I want it to be repairable.
 
Case in point, a video popped up that shows a very recent design technology that proves clearly that most PCB designs are not made for the best technical operation, but to meet an aesthetic with only a consideration to electrical performance. I.E. your PCB circuit boards are made to look good first and perform well secondly. You can interchange the priority if you like, but in the end, you still have the compromise.
[/video]

Don't believe everything you see/read on the internet. (Especially when links are not provided)

We get it you don't like PCB, but here you're trying to give "reasons" to improve your credibility. Maybe you feel like you "lost" one of the other arguments in another thread and you needed to "set the record straight".

One thing I learned (in a psychology class of all places), is that people who are critical are perceived to be more knowledgeable and intelligent. Which means that the internet is full of people trashing things for clicks. And then other people cite them as experts and use them in their own bitch sessions.

My honest opionion? You are a hobby builder who has copied some designs over the years. But as you don't sell amps you haven't discovered the lessons learned from building at scale. Old man shouting at clouds.
 
Also, if you are an "amp builder" you should learn how to build your own PCB designs. Anyone can layout circuits and have boards printed.
 
I once had a TC Electronic M350 the PSU board of which went short circuit blowing fuses. I took it to the local TC service center who apparently provided no repair, only replacement. The cost for a new PSU board was unreasonable compared to the price of the unit itself. So I took the thing home and put it up for sale as is. I managed to sell it for 100 bucks in 4 hours and used the money to buy a Zoom MS70 CDR.

This PTP vs PCB thing is just for tech/ hobbyists, no? In the real world most players don't care and don't know if it's PCB, PTP, PCP, etc. They just want amps that deliver at the most reasonable cost.

PCB is the solution cause it's affordable. Not every player has the money or reason to drop 3K for amps that they can pass to their grand kids.

And really, who doesn't like buying a new amp every 5 years. You can't escape GAS...lol...
 
Top-L, I would go back to psych class, because you are far from being a Dr. with your assessment. You are also being quite the hypocrite in this case. Pot calling a kettle black. I don't care about credibility, the information is widespread and freely available for you to create your own opinions. I presented a video from someone who seems to have more than enough credibility to not need my help, and I found it interesting that despite where we are at technologically speaking, PCB design is only recently turning pages. You assume I have never made or created a PCB design... You know what happens when you Assume right?

You're being rather critical for someone who doesn't know much about who he is criticizing. I didn't wake up three days ago and say " you know what, ima build guitar amps "... I didn't copy anyone's work, I have several genuine designs. I have stated clearly it is VERY hard to create a new design at this point without stepping on toes at least a little bit. Many Fender circuits came straight from the RCA receiving tube manual. I would say that you cary zero credence to criticize me and my work, of which you appear to have zero clues about, considering your lack of intelligent contribution to not only the subject matter but to the amount of couth you display when throwing shade. I also find it hard to connect amplifier circuit design to building at scale? You come to a circuit design, and you either build it or you don't, how you make it is up to you. I think it is clear to say that I am far from interested in trying to build 10,000 amplifiers a year, so I have ZERO need to worry about whether it takes me three weeks to build an amp or 30 min. I don't sell amps to the general public ( as of yet ), I didn't say I was never commissioned to do so for a fee. What it costs to build an amp is what it costs. What It costs to buy an amp is what it costs to buy it. If Alex Dumble were still alive, how much would he sell you an amp for, if he would even bother to do so?

Being rude doesn't make your point more poignant. All it does is show your character flaws. Your first post in this thread and you're a psych major all of a sudden... with an innate knowledge of a stranger's past accomplishments and skills. How do things look from that perch you are sitting on; looking down upon all us pee on's... Holy hell, I have gotten more respect from rats that I pee'd on in an alley while drunk. Just be nice, and speak of facts, and certainly don't speak to things which you could drown in 1/2" an inch of water from.

Simply wow, just so much wow. Rude much...
 
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Don't believe everything you see/read on the internet. (Especially when links are not provided)

We get it you don't like PCB, but here you're trying to give "reasons" to improve your credibility. Maybe you feel like you "lost" one of the other arguments in another thread and you needed to "set the record straight".

One thing I learned (in a psychology class of all places), is that people who are critical are perceived to be more knowledgeable and intelligent. Which means that the internet is full of people trashing things for clicks. And then other people cite them as experts and use them in their own ***** sessions.

My honest opionion? You are a hobby builder who has copied some designs over the years. But as you don't sell amps you haven't discovered the lessons learned from building at scale. Old man shouting at clouds.

Also, if you are an "amp builder" you should learn how to build your own PCB designs. Anyone can layout circuits and have boards printed.

:33:

And how many amps have you built?
 
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