How anal to be about components?

Hey ya'll. So after spending a good couple of hours measuring a bunch of resistors for a few builds, I sort of sat back and took a deep breath and wondered "Do I really need to be doing this?".
I'd built a number of pedals previously without ever measuring any component. Most of those builds were basic enough that I don't think they sound bad or sound too far from an original, but after taking some notes from pedal builders, yeah, I decided I should start measuring my caps and transistors, etc.
The thing is – how anal do I really need to be about it?
Do I really need to sweat a 1r resistor being .997r? Or a 10m resistor being 9.997m?
Is it worth really finding the perfect component value of a cap or transistor or diode? If I'm close but not exact, do I need to order another batch to fish through?
Are the professional pedalmakers all measuring out each and every component to an exact spec? Or do they allow for some variance as well? (I just watched a video from JAM pedals where it looked like maybe they don't)
What's your advice and where do you draw the line for how obsessive to be (for your own sanity and those around you)?
Would love to hear from ya'll and see if I need to up my game or chill waaaay out.
Thanks!
 
Are the professional pedalmakers all measuring out each and every component to an exact spec?

Of course they are! Haven't you read their marketing hype? :ROFLMAO:

Seriously though... I'm sure some do, but I'm also certain that some don't.

I don't measure before I install... It's not a bad practice though, because you can identify an incorrect value before it ever goes in. I'd say incorrect resistor values account for at least 90% of the troubleshooting threads here. I've never gotten a mislabeled component that I'm aware of (mislabeled packaging, yes, but not a component that actually had the wrong value printed on it) but it does happen occasionally.

As far as being anal about the tolerance of the component... It depends on the circuit. Most metal film resistors are spec'd at 1% tolerance, carbon film at 5%... The old carbon comp resistors that everyone loves so much were spec'd at 20% tolerance.

Most of the audio circuits we deal with just aren't that critical... When I worked in the consumer electronics repair industry we were generally fine with 10% wiggle room in most anything non-critical (critical being SMPS power supplies/regulation, tuned circuits, etc)...

If you really want to get anal you can start worrying about the accuracy of your DMM.... For example the Fluke 117 specs state that the accuracy of the resistance measurement is 0.9%.... Combine that with the 1% of a metal film resistor and your 100K resistor could be off by an entire 1.9K! That's NINETEEN HUNDRED OHMS. Before long we're sitting in a temperature/humidity controlled environment giving our equipment the proper 4 hour warm-up time before biasing a JFET in an overdrive circuit "to ear". :ROFLMAO:
 
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as noted, the troubleshooting topic show that incorrect parts installed in a build account for a lot of the problems. it is not that any part is off value by a little bit, it is that the builder misread the part value that was supposed to be used or had a bag with the wrong part value written on it. double checking the value with a DMM gives people a chance to double-check the part value.

that is also a much faster checking process than trying to find your part that is exactly in spec, fortunately.
 
I have gotten into the habit of measuring each component before I install it. It really doesn't take that much extra time.

I actually will firstly go through and get all the resistors I need and put them onto the board in groups. Then I do the same with the diodes, film caps, elec caps, etc. It really helps to cut down on errors, and then I know up front is a component is off.
 
The only things I measure are transistors for hfe if the circuit needs specifics, JFETs/mosfets and once in a blue moon I’ll measure a cap or two but now that I buy decent ones it’s not really necessary. With resistors I just measure ten out of the 100 or so I usually buy and if they check out they go in the parts bin.
 
Wow, people actually do that? This is the first I'm hearing it. It's a lot faster to learn to read the color codes and trust the manufacturer. I know it isn't a very "mojo" line of thinking, but I've always been taught that if the value is within 10% of spec then you likely won't hear a difference. I mean plenty of commercial builders use 10% tolerance components anyway, a lot of caps are 20% tolerance. Do they all add up to making a difference between the units? Sure, but how many people can really hear the difference between a 100k resistor and a 98.1k resistor?
 
If I get a big batch of parts or order from somewhere I haven't before, I measure a few just to make sure they didn't send me pure trash. From there, I find it much faster just to trust the writing or the color code than to measure everything. If I build something and it sounds weird, the time I spend troubleshooting and fixing that unit is still less than the time I would have spent measuring every part for every project before it that did work. Think about consumer or industrial electronics manufacturers- they don't measure every single part before loading it into a pick'n'place machine. Instead, they rely on QA to catch any problems. If you don't trust that a 1% 100 ohm resistor is really 99 to 101 ohms, buy them somewhere else. The 7 cents you save per project probably isn't worth the amount of time you waste measuring, to say nothing of the wasted money on out-of-spec garbage you end up not being able to use. However, your mileage may vary; germanium transistors need not apply.
 
For folks that are still building their first few pedals, or even their first few dozen, it makes a lot of sense to have them check the part number on a capacitor and the part values for resistors with a DMM before soldering them in place. Those are the builds where a wrong part value is most likely to get used, and also the builders who are more likely to have trouble fixing the problems that show up in the builds.
 
I have gotten into the habit of measuring each component before I install it. It really doesn't take that much extra time.

I'm with chongmagic on this one -- for me, it cuts down on error and 9 times out of ten, my builds fire right up.

It's amazing too how many mislabeled parts I've received from Tayda, Mouser, Digikey, Newark, etc.
 
I measure all my resistors as they go on and I spot check caps, and I do check transistors as I acquire them to be sure I didn't get fakes
 
I always check the value of resistors as I build. Not so much because I think they may be out of spec but because it's a good way of double-checking the value. When I'm building an amp with 1W carbon film resistors I can tell you the value of each resistor easily. But when populating a board with 1/4W metal film resistors it's all too easy to make mistakes.

I used to measure the caps but that got old. The values are much easier to read anyway! Transistors I'll check if hfe is important or they're Ge.
 
Of course they are! Haven't you read their marketing hype? :ROFLMAO:

Seriously though... I'm sure some do, but I'm also certain that some don't.

I don't measure before I install... It's not a bad practice though, because you can identify an incorrect value before it ever goes in. I'd say incorrect resistor values account for at least 90% of the troubleshooting threads here. I've never gotten a mislabeled component that I'm aware of (mislabeled packaging, yes, but not a component that actually had the wrong value printed on it) but it does happen occasionally.

As far as being anal about the tolerance of the component... It depends on the circuit. Most metal film resistors are spec'd at 1% tolerance, carbon film at 5%... The old carbon comp resistors that everyone loves so much were spec'd at 20% tolerance.

Most of the audio circuits we deal with just aren't that critical... When I worked in the consumer electronics repair industry we were generally fine with 10% wiggle room in most anything non-critical (critical being SMPS power supplies/regulation, tuned circuits, etc)...

If you really want to get anal you can start worrying about the accuracy of your DMM.... For example the Fluke 117 specs state that the accuracy of the resistance measurement is 0.9%.... Combine that with the 1% of a metal film resistor and your 100K resistor could be off by an entire 1.9K! That's NINETEEN HUNDRED OHMS. Before long we're sitting in a temperature/humidity controlled environment giving our equipment the proper 4 hour warm-up time before biasing a JFET in an overdrive circuit "to ear". :ROFLMAO:
Okay, phew! Haha! I was kind of mortified at the idea that I had totally botched a number of pedals by not measuring out each and every component, especially since they've all sounded like they should...or do they????? o_O
 
Glad to hear all of your hot takes. I'm glad I won't need to be THAT obsessive (but still mildly, amiright?) for the future. Thanks!
 
Like Chong I measure all my resistors. I use one of those cheap component testers. I'm not looking for value accuracy (unless something is way out of whack) because I suspect the accuracy of the tester is pretty loose. I'm just looking for a sanity check that I'm not reading the value wrong. For the small amount of extra time it takes it reduces my troubleshooting time to close to zero.

I AM anal enough to make sure the color codes and markings all orient the same.
 
I just recently started measuring components. My ocd and ar started controlling me. What I’ve found so far is that I’m not too concerned about the 1% resistors. They’ve all been pretty consistent. The electros and film caps have have been hit or miss depending on the brand. Some of them seem to push that 20% to the extreme. I’ve found Nichicon electros to be the best of those I’ve tested. Even the Wima 5% have had a pretty generous sweep at times. The worst of the component’s that I’ve tested seem to be the mlcc’s in the smaller pF values, especially the ones I’ve got from Tayda. These have had huge differences. I have no way that I know of to test transistors at the moment
 
All good advice here. I'm not trying to shame anybody out of measuring components to any degree. If the effort to double check everything is less than the effort of troubleshooting and reworking, do what makes sense! Just don't feel you have to if you aren't seeing any benefit. Making sure resistor color codes are all oriented the same direction, however, is mandatory.:p
 
I just recently started measuring components. My ocd and ar started controlling me. What I’ve found so far is that I’m not too concerned about the 1% resistors. They’ve all been pretty consistent. The electros and film caps have have been hit or miss depending on the brand. Some of them seem to push that 20% to the extreme. I’ve found Nichicon electros to be the best of those I’ve tested. Even the Wima 5% have had a pretty generous sweep at times. The worst of the component’s that I’ve tested seem to be the mlcc’s in the smaller pF values, especially the ones I’ve got from Tayda. These have had huge differences. I have no way that I know of to test transistors at the moment
I totally hear you! I've had a few caps that were outside of their marked tolerance (which was a little disconcerting) but I think those were in that 20% range that is definitely pretty wide at times. 1% or even 5% I'll probably not sweat too much, but those 10% or more might need a double check for sure. Good call.
Which transistors are you trying to measure? There are a couple of quick and easy schematics you can build with some components and a 9v battery that are out there I could dig up if you need!
 
The old carbon comp resistors that everyone loves so much were spec'd at 20% tolerance.

If you wrap a mil-spec resistor in fake carbon comp casing, does that give it *more* mojo, or less?

 
All good advice here. I'm not trying to shame anybody out of measuring components to any degree. If the effort to double check everything is less than the effort of troubleshooting and reworking, do what makes sense! Just don't feel you have to if you aren't seeing any benefit. Making sure resistor color codes are all oriented the same direction, however, is mandatory.:p
Yeah I don’t do it on a regular basis. I was just hard at it one day and the curiosity killed me and I thought to myself, let me check some of these out just for shits and giggles.
 
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