Is it a good idea to build parts of the circuit off board, such as input/output caps on the jack (directly), or tone caps directly on the tone pot?
Im getting into 1590A enclosures, so I want to minimize the size of the circuit if possible.  Im thinking that I can get ~1/2 of the circuit offboard, but dont want any issues down the road....any thoughts?


thanks!

There might be some very minor tonal differences, which the EE's could explain, but I don't think that most people would be able to hear any difference.

Having said that, there are cases where the position of the component does make a discernible difference, most often when filtering the power supply voltage.

Quote from: noobamp on July 06, 2013, 07:34:51 PM
Is it a good idea to build parts of the circuit off board, such as input/output caps on the jack (directly), or tone caps directly on the tone pot?
Im getting into 1590A enclosures, so I want to minimize the size of the circuit if possible.  Im thinking that I can get ~1/2 of the circuit offboard, but dont want any issues down the road....any thoughts?

It is a bad, bad, bad idea to mount components flying off the PCB to jacks, controls, etc. unless there is simply no way around it.

It is a bad idea for reliability and service reasons. Most components are designed for PCB insertion, not hanging by their leads. You can often get away with it for resistors, but the bigger the cap, the more it flexes its leads and whatever holds the lead onto the body with every mechanical shock.

Then there is the issue of how you'll fix it if it breaks. Unsoldering a bunch of components to get it out of the box is a very frustrating experience.

Put the parts on a board of some kind to mechanically support them. If you can't, get smaller components or a bigger box. If you must leave leads flying, support the parts by pouring the box full of potting goo. 

That's my own personal opinion. There is no charge.

I am going to whole-heartedly disagree with RG on a number of points.

There is nothing wrong at all with mounting off-board components as long as you plan ahead and observe proper soldering technique. I would also argue that fixing off board components is usually easier than having to pull a board out and/or disturb the entire build - that can be a true pain.

There are plenty of builds where you can mount caps and resistors to pots just as securely as they would be attached to a board. I frequently use power filtering caps wired directly to the DC jack or resistors and caps directly on pots ot soldered to another component. A great use of space is to solder caps or diodes right on a swtich. It saves room and is much easier to change or swap out than pulling a board out of the enclosure. There is no added strain on a component in the least. You can find plenty examples of ancient guitar amplifiers and pedals that have components wired directly to pots or other off board areas. They seem to be durable enough to last several decades and be used daily by professional touring musicians.

I love building true PTP builds. Some of the best amp and pedal builders on the planet use true PTP techniques with no boards involved at all. They could potentially be more difficult to troubleshoot and/or fix but they are perfectly durable.

Edit:

PIGDOG!

Why did you think this was a "quick" question?

I agree with both RG and AA on different days.

I actually find some board mounted components can be the weakest link of a build. PCB mounted pots are garbage for durability. I also think transistor sockets are timebombs unless you glue the transistor in place afterwards.

Quote from: Arcane Analog on July 06, 2013, 09:25:19 PM
I am going to whole-heartedly disagree with RG on a number of points.

That's fine. My opinion is worth no more than it cost to get.

Quote
There is nothing wrong at all with mounting off-board components as long as you plan ahead and observe proper soldering technique.

I will conditionally agree with that as long as you underline, boldface, and italicize "as long as you plan ahead and observe proper soldering technique."
Your picture shows some decent PTP technique. However, in my experience, it's notable because it's the exception. My experiences with resistors or cap soldered in series with one end of a wire are legion.

QuoteI would also argue that fixing off board components is usually easier than having to pull a board out and/or disturb the entire build - that can be a true pain.

I would also agree with you for the exception builds, where the components are laid out with that in mind inside a box that's big enough to hold both them and the soldering iron tip and whatever surgical manipulator you're using to move the unsoldered ends. However, again, your picture is very much the exception, not the rule.

QuoteThere are plenty of builds where you can mount caps and resistors to pots just as securely as they would be attached to a board.

Yes - if they are axial components, and the lead length is not grossly longer than it would be on a PCB, and both connections (all three for a transistor, all leads for an IC) are as solidly supported mechanically as they are on a board. Well, "just as securely" discounts the support that the body would provide in damping any body movement, but that's probably OK for small caps and resistors. It's not the case with a radial electro bigger than about 6mm diameter, unless you also glue the body down to something.

QuoteI frequently use power filtering caps wired directly to the DC jack or resistors and caps directly on pots ot soldered to another component. A great use of space is to solder caps or diodes right on a swtich. It saves room and is much easier to change or wap out than pulling a board out of the enclosure. There is no added strain on a component in the least. You can find plenty examples of ancient guitar amplifiers and pedals that have components wired directly to pots or other off board areas. They seem to be durable enough to last several decades and be used daily by professional touring musicians.

The issue we're dancing around is probably best summarized in the skill of the builder. It's not that PTP can't be done well - it's that people with no training and low hours on a soldering iron, and not much time looking at good examples of PTP, and who would like to make boxes very small are unlikely to be able to do it well for quite a while.

Quote
I love building true PTP builds. Some of the best amp and pedal builders on the planet use true PTP techniques with boards involved at all. They could potentially be more difficult to troubleshoot and/or fix but they are perfectly durable.

Again, I'd quibble with "perfectly". They're durable enough if well done by skilled practitioners.

QuotePIGDOG!

Nice craftsmanship - but I don't think I'd change my advice to the OP.

That's just my opinion. It's OK for people to go learn to be electronic sculptors if they want.

Sometimes when you're looking at some old bit of kit you have to ask "why did they do it like that?"

Perhaps the tagboard was cheaper than getting a small batch of pcbs made in 1968. Perhaps it's the kudos that it inspires in people who habitually buy jars of snake oil from guys with perfect teeth and snazzy suits. Perhaps it's just one of those things and there's no point in wasting time worrying about it.

I don't think there's anything wrong with e.g. wiring a component across a jack socket so long as it's not going to get physically fatigued by movement from repeated insertions of the jack plug. Note that I wrote "across a jack socket" and not "from the jack socket to somewhere else, miles away". Perhaps it's a long way to the board and it's a least bad option to e.g. mount a buffer fet on the socket with some dead bug origami (or the wire equivalent thereof).

Perhaps it's an RF thinger and lengths of wire are out of the question.

But having components flapping about under their own weight on flying leads might be less than optimal some of the time. You might want to design it out when appropriate.

Unless your customers like that sort of thing. [/$0.02]

What would be the difference between poor soldering technique of on board components versus the same poor technique of off board components? It seems to me to be a useless comparison. All things being even, if you soldering the component correctly, off versus on board has no bearing. I mentioned that only to remind of the importance of good technique. The reference to planning was simply to highlight that it is good practice to think about your layout before soldering.

None of my suggestions have anything to do with exception builds. The can be used on every and any build and off board components are almost always going to be easier to replace over disturbing a PCB after it has been finished and installed.

Radial components work just as well as axial - sometimes better - with pots and DC jacks being typical. They do not require any glue or goo to be installed with durability in mind. I never use glue. That would make repalcing that part more difficult. If you can grab the cap and watch the pot's lugs move I doubt adding a little glue is going to be of any utility. Mechanical support for caps commonly used in pedals is not a major factor. If they are soldered porperly they need little additional support unless you plan on opening up the pedal and manipulating components with your fingers or pliers. Wear and tear is not going to be an issue with a cap properly soldered to a pot or properly soldered to a switch.

You do not need to be a tremendously gifted or skilled builder to observe porper soldering technique. That is a basic skill developed from the moment you begin building. It does not matter if you are soldering off or on board. If your soldering technique is poor on/off board is not the pressing concern. The photo of the Pigdog was for fun. We are currently concerned with adding a few off board parts here and there. The skill level required for soldering on versus off with a view to the current topic is of marginal difference - if there is any difference at all.

There is no difference in durability with a cap properly soldered to a pot and one properly soldered to and supported by a board. Once the pedal is boxed up there is no difference with regards to mechanical support. They will both be fine unless you deceide to frequently open the pedal up and wiggle your components. I use tagboard almost exclusively and I can tell you that the components soldered to the tags that do not touch the board (transistors, caps, resistors and leads included) are as solid as those that do. You would need cutters to remove them. The same goes for components attached to the lugs of a pot, switch or jack. They do not need any support other than the soldered connections. You would have to work the leads pretty damn hard with your fingers to cause any damage and you can watch the solder lugs of the pot flex and move as much as the component does.

If you were to grab any of the caps on this board and try to move them the tags are moved first. No mechanical support other than the soldering joint is needed.

Quote from: gritz on July 06, 2013, 10:44:55 PM
Sometimes when you're looking at some old bit of kit you have to ask "why did they do it like that?"

Perhaps the tagboard was cheaper than getting a small batch of pcbs made in 1968. Perhaps it's the kudos that it inspires in people who habitually buy jars of snake oil from guys with perfect teeth and snazzy suits. Perhaps it's just one of those things and there's no point in wasting time worrying about it.

Tagboard is tens-times more duarable than a PCB. PCBs are used because they are cheaper to manufacture and you can print pretty little pictures on them to make populating them dead easy.

Quote from: gritz on July 06, 2013, 10:44:55 PMI don't think there's anything wrong with e.g. wiring a component across a jack socket so long as it's not going to get physically fatigued by movement from repeated insertions of the jack plug. But having components flapping about under their own weight on flying leads might be less than optimal some of the time. You might want to design it out when appropriate.

How would the repeated insertion of a jack fatigue the wire leads connected to the lugs less than the leads of the component?

Quote from: Arcane Analog on July 06, 2013, 10:54:53 PM

Quote from: gritz on July 06, 2013, 10:44:55 PM
Sometimes when you're looking at some old bit of kit you have to ask "why did they do it like that?"

Perhaps the tagboard was cheaper than getting a small batch of pcbs made in 1968. Perhaps it's the kudos that it inspires in people who habitually buy jars of snake oil from guys with perfect teeth and snazzy suits. Perhaps it's just one of those things and there's no point in wasting time worrying about it.

Tagboard is tens-times more duarable than a PCB. PCBs are used because they are cheaper to manufacture and you can print pretty little pictures on them to make populating them dead easy.

Tagboards are held together by riveting, as are aeroplanes. However, I'm pretty sure that they're not inspected to the same rigorous standards, nor are aeroplane panels subjected to abuse by folks with oversize soldering irons and Chinese solder. I can see from your pics that you know what your doing, but don't make the mistake of assuming that everybody else does. For instance, if someone copied your tagboard layout, but left the leads on those axial capacitors *just a bit longer* and the assembly was subject to prolonged vibration, or a bit of g in the wrong direction then there may be smoke. PCBs are subject to many pitfalls too, but they're usually of the "oh, I overcooked it and the trace fell off" variety.

Quote from: Arcane Analog on July 06, 2013, 10:54:53 PM

Quote from: gritz on July 06, 2013, 10:44:55 PMI don't think there's anything wrong with e.g. wiring a component across a jack socket so long as it's not going to get physically fatigued by movement from repeated insertions of the jack plug. But having components flapping about under their own weight on flying leads might be less than optimal some of the time. You might want to design it out when appropriate.

How would the repeated insertion of a jack fatigue the wire leads connected to the lugs less than the leads of the component?

Half-arsed assembly by people who just copy without thinking. And cheap, bendy jack sockets.

In case you didn't notice I did put a (limited) case for the defence of point to point - despite my better judgement. I am also a fan of AM radio and steam power.

Edit: curse these quote tags!  

Quote from: gritz on July 06, 2013, 11:20:01 PM


Tagboards are held together by riveting, as are aeroplanes. However, I'm pretty sure that they're not inspected to the same rigorous standards, nor are aeroplane panels subjected to abuse by folks with oversize soldering irons and Chinese solder. I can see from your pics that you know what your doing, but don't make the mistake of assuming that everybody else does. For instance, if someone copied your tagboard layout, but left the leads on those axial capacitors *just a bit longer* and the assembly was subject to prolonged vibration, or a bit of g in the wrong direction then there may be smoke.

I take nothing for granted on soldering/building skills. I mentioned the importance of proper technique in every post.

Inspection of a tagboard has no bearing on its superior durabilty over a PCB and is of no utility in this discussion. The connections made with a tag over those made to a PCB trace is the deciding factor. No comparison. Tag wins hands down. Obviuosly tag is not practical for most applications. The reason I raised it in this context was to simply point out that tag is very similar to using off board connections.   

Quote from: gritz on July 06, 2013, 11:20:01 PM
Half-arsed assembly by people who just copy without thinking. And cheap, bendy jack sockets.

What is the difference between wire leads versus component leads in connection with "half-arsed assembly by people who just copy without thinking and cheap, bendy jack sockets"? It seems to me that there is no difference between wire versus component - either works just fine. Your response does not address any differnce. Poorly executed work will have little differnce with a wire lead versus a component.

Quote from: Arcane Analog on July 06, 2013, 10:48:36 PM
What would be the difference between poor soldering technique of on board components versus the same poor technique of off board components?

It is even more critical with off-board components, as this is the only mechanical fixing the part has.

QuoteIt seems to me to be a useless comparison.

It seems not to be useless to me.

Quote
All things being even, if you soldering the component correctly, off versus on board has no bearing.

Yes, all solder joints should be perfect. Off-board placement without a hole - or terminal - to fix the leads mechanically before soldering is tougher to do because you have to hold the parts still. This is fine where you're soldering to fixed terminals. It's not where, as I mentioned, someone solders a resistor in line with one end of a wire. So all things are not always equal.

QuoteI mentioned that only to remind of the importance of good technique. The reference to planning was simply to highlight that it is good practice to think about your layout before soldering.

Yes, good planning is as important as respecting your mother and eating apple pie.

QuoteNone of my suggestions have anything to do with exception builds. The can be used on every and any build and off board components are almost always going to be easier to replace over disturbing a PCB after it has been finished and installed.

It depends on your perspective. Grizzled old tube amp techs would (almost!) rather starve than work on PCBs. If a PCB is difficult to install and replace when repaired, the PCB design is sloppy, but that's not the issue we're discussing here. I have a litany of PCB designs that make service a nightmare. None of those mean that with, as you say, planning and pre-thinking, PCBs *can't* be much easier to install and service, right down to being able to be removed by unplugging. There are always greater and lesser practitioners of every art.

I have to admit that I have to suppress a sigh when I see PCBs with wire leads exiting more than one edge, and with wires on all edges, tied down like Gulliver in Lilliput, it's really, really difficult to work on them without tearing stuff up. But with long practice, I can now suppress a snicker when I'm in polite company.

QuoteRadial components work just as well as axial - sometimes better - with pots and DC jacks being typical.They do not require any glue or goo to be installed with durability in mind. I never use glue.

Size matters. "Sometimes" is just that, sometimes.

QuoteThat would make repalcing that part more difficult. If you can grab the cap and watch the pot's lugs move I doubt adding a little glue is going to be of any utility. Mechanical support for caps commonly used in pedals is not a major factor. If they are soldered porperly they need little additional support unless you plan on opening up the pedal and manipulating components with your fingers or pliers. Wear and tear is not going to be an issue with a cap properly soldered to a pot or properly soldered to a switch.

You do not need to be a tremendously gifted or skilled builder to observe porper soldering technique. That is a basic skill developed from the moment you begin building. It does not matter if you are soldering off or on board. If your soldering technique is poor on/off board is not the pressing concern. The photo of the Pigdog was for fun. We are currently concerned with adding a few off board parts here and there. The skill level required for soldering on versus off with a view to the current topic is of marginal difference - if there is any difference at all.

There is no difference in durability with a cap properly soldered to a pot and one properly soldered to and supported by a board. Once the pedal is boxed up there is no difference with regards to mechanical support. They will both be fine unless you deceide to frequently open the pedal up and wiggle your components.

I'm detecting that I struck a nerve here. 

QuoteI use tagboard almost exclusively

I would have guessed that. 

Quote
and I can tell you that the components soldered to the tags that do not touch the board (transistors, caps, resistors and leads included) are as solid as those that do. You would need cutters to remove them. The same goes for components attached to the lugs of a pot, switch or jack. They do not need any support other than the soldered connections. You would have to work the leads pretty damn hard with your fingers to cause any damage and you can watch the solder lugs of the pot flex and move as much as the component does.

Again, a solid lug on each end of a part is an OK mechanical fixture. Tell me again how this works with flying resistors? This reminds me a lot of the T-shirts that circulated after the Three Mile Island reactor near-meltdown. They had screen printed on them "I survived Three Mile Island - I think..." Everything works great until it doesn't.

QuoteIf you were to grab any of the caps on this board and try to move them the tags are moved first. No mechanical support other than the soldering joint is needed.

Very neat, tidy work. Looks very sturdy.

Let me ask you this - the military can have any building style they like. They quit specifying tagboard and point-to-point a while back. Why was that? It wasn't cost - they are practically synonymous with "I can pay for anything."

all very good points, and as all the advise comes together, I feel like i have a better idea about things that can/cant be off board.....I guess it turned out to be a not-so-quick question after all....
Ill minimize the components which will be moving around (anything on a jack), but may keep components that will "never" move (cap and res on a tone knob, with no stress).  Ill go back to the drawing board and see if I can get a better design......

you guys all rock....thanks!

I really do not have the time to answer/address everything, but...

Quote from: R.G. on July 06, 2013, 11:38:38 PM
Let me ask you this - the military can have any building style they like. They quit specifying tagboard and point-to-point a while back. Why was that? It wasn't cost - they are practically synonymous with "I can pay for anything."

Again, somewhat of a useless direction. I would wager the simple fact that, as you pointed out, size matters. Would you like a cell phone made with tagboards? I doubt the military would find it practical to make a missle PTP. I would suspect that cost certainly does factor in the equation. So does speed/mass production and micro technology.

This is a pedal forum. The question in this thread is related to pedals.

Quote from: noobamp on July 06, 2013, 11:50:20 PM
... but may keep components that will "never" move (cap and res on a tone knob, with no stress)...

I think that something like this is *not the end of the world* - i.e. no reasonable likelihood of movement between the two mounting points (lugs on the same pot which are nice and close together) .So long as there's no possiblilty of the components that are hanging off the pot flapping about or fouling anything then it's a bearable situation - 'spesh if it's a stripboard layout and it saves a row of holes and means that your board is actually going to fit in that box...

However: Anyone who's just getting to grips with this kind of stuff shouldn't be surprised if old timers insist that they follow proper (and possibly boring / expensive) procedure - at least until they know precisely what they can and cannot get away with. And that goes for people who cry "but I've always done it this way and I've never had a problem!" too. I'm sure that many of us have a geriatric relative who's smoked for sixty years but has never had a day's ill health. It's possibly not a lifestyle to be recommended though.

@gritz: i completely understand that......at times, I am the one that will do it the hard way because its tried and true---to me---regardless of what other folk find to be easier/better....the important thing is that hearing enough people say yea or nay ether way gives me a much more complete story, and from there, I can draw out a best fit plan......thanks a ton guys!

My $0.02: 

One of the things I remember my dad teaching me about soldering is that each solder joint has to have a good mechanical connection. The solder joint is an electrical connection and should not be relied upon to prevent torsional stresses or stress perpendicular to the leads.  PCBs work well because in almost all cases, the only directional force that the solder joints can "feel" is along the direction of the leads (as if you were trying to pull the components straight up off of the board with your fingers). The solder joint can easily hold the component in place because it has a "foot" on the opposite side of the board.  With the bottom of the components flush or very close to the board, there's little chance for lateral forces to act upon the solder joint.  However, if you were to solder a lead flat against another surface, then you expose the lead to forces in many directions.

As mentioned by others above, another thing related to the mechanical connection is that the component's weight has to be supported in a way that prevents it's leads from breaking from fatigue over time.

A small, light weight ceramic cap having 1/8" leads, soldered between two lugs on the same jack, is probably not a problem, provided the leads were placed through the lug holes and bent around the lugs prior to soldering (assuming the solder joint itself is good). Try that with a large 4700μF electrolytic cap and it won't last long. Sometimes top-heavy components on PCBs are glued to an adjacent component that's more sturdy.

Try to imagine what happens to your off-board components when the stompbox gets dropped.

Notice in these two photos how the soldered leads are just lying against each other with no mechanical connection before soldering. Not Cool:





This shows a couple of caps hanging out and at risk of the leads breaking:



These photos show mechanical connections before soldering:







These photos show lightweight components with short leads. These are much less likely to break off than the ones above that have one lead soldered to a lug and the other one to a wire.

Quote from: Arcane Analog on July 06, 2013, 11:51:11 PM
I would wager the simple fact that, as you pointed out, size matters. Would you like a cell phone made with tagboards? I doubt the military would find it practical to make a missle PTP. I would suspect that cost certainly does factor in the equation. So does speed/mass production and micro technology.

Hmmm. Size matters. OK.
But the original poster's question was about size, wasn't it?

And so it can be cheaper to do circuits on boards. 
And faster to produce.
And use smaller parts.

I think I have to agree with you. Putting things on boards instead of point to point can be smaller, cheaper, faster, and use more/different technology than PTP.

But I think those things matter in pedals sometimes, yes?   

And thanks for the following. This is what needed to be typed in and photos presented. I was just too lazy and pig-headed to do it.

Solder is not glue. It cold flows and fatigue cracks with any provocation at all.

Quote from: Jdansti on July 07, 2013, 02:47:46 AM
One of the things I remember my dad teaching me about soldering is that each solder joint has to have a good mechanical connection. The solder joint is an electrical connection and should not be relied upon to prevent torsional stresses or stress perpendicular to the leads.  PCBs work well because in almost all cases, the only directional force that the solder joints can "feel" is along the direction of the leads (as if you were trying to pull the components straight up off of the board with your fingers). The solder joint can easily hold the component in place because it has a "foot" on the opposite side of the board.  With the bottom of the components flush or very close to the board, there's little chance for lateral forces to act upon the solder joint.  However, if you were to solder a lead flat against another surface, then you expose the lead to forces in many directions.

As mentioned by others above, another thing related to the mechanical connection is that the component's weight has to be supported in a way that prevents it's leads from breaking from fatigue over time.

A small, light weight ceramic cap having 1/8" leads, soldered between two lugs on the same jack, is probably not a problem, provided the leads were placed through the lug holes and bent around the lugs prior to soldering (assuming the solder joint itself is good). Try that with a large 4700μF electrolytic cap and it won't last long. Sometimes top-heavy components on PCBs are glued to an adjacent component that's more sturdy.

Try to imagine what happens to your off-board components when the stompbox gets dropped.

In all applications technology moves on, PTP when thought out and planned correctly looks really nice and works as it should. Try to build something more complex than an amp and you will soon find it is something that can become amazingly hard to troubleshoot, we would end up back in the days were computers fill whole rooms and are no more complex than a calculator if we hadn't moved on to PCB and indeed SMD.

PTP for me is not an issue, I love to see some well designed circuits using point to point, I see it more of an art than anything else.  My problem with it is that some people think by designing a PTP circuit it is the Holy Grail and warrants a ridiculous price, pretty but just advertising price hiking bollocks.