If I want high action do I also want a straighter neck?

Wow wow wow.
Neck curvature is set to naturally follow the movement of the strings. It is not used to adjust action.
Action is adjusted by the height of saddles.
Shimming is used to adjust the angle between neck and body so that action can be adjusted within the range of the bridge.
Finally, intonation issues are corrected by adjusting the length of each string at the bridge.

More relief doesn't mean a lower action. High action doesn't require a straight neck. If your intonation is wrong you need to adjust string length by moving the saddles.

 

Intonation issues above the 12 fret are corrected by adjusting string length. Neck curvature plays little to no role in it.

 

First, .021 of relief is excessive, low action or not. The point of relief is to allow a little extra clearance for the vibration of the strings on frets 1 to 5. If you have high action you already have more clearance at those frets so you need less relief, if any at all. Start with the neck straight and adjust the height at the saddles to your preference. If you are getting fret buzz anywhere from frets 1 to 5, add a little relief, re-adjust the saddle height and and check for buzz again. Repeat until you are satisfied with the playability.

 

As said the only point of having relief on a neck is to give the strings fretted on the about 5 first frets more room to vibrate, higher action will to some extend call for less need of that and hence require less relief.

No point in having relief on the neck if there is no use of it, so technically yes to your question.

I will always set the relief to as little as possibly needed not to get fret buzz on the first couple of frets, and you might find you won't need any if your action is sufficiently high.

 

Comparing the harmonic with the fretted note doesn't fix intonation, it just lets you hear how off it is.
The only way to adjust intonation is to adjust string length at the bridge.
Well, you could move the frets, but that requires a lot more work.

 

Even if the 1st statement is true (and i'm unsure it is), it doesn't then mean the 2nd statement is true.
The 2nd statement isn't true, neck relief is adjusted to equalise the amount of fret buzz (or lack of it) across all the frets, whether you have high or low action.

Neck relief doesn't cause bad intonation, intonation can always be fixed by adjusting the saddle hotrizontal positions.

I've posted about this several times, the 2nd harmonic/12th fret method is commonly stated but is inaccurate and prone to error, it's a method only to be used when you don't have a tuner.

Use a tuner to tune the open string, then use it to check the pitch of the 1st fret, then the pitch of every 2nd or 3rd fret up to the highest played fret.
The reason your high frets are poorly intonated is because you have only checked the 12th fret for intonation. Higher frets are increasingly sensitive to saddle adjustments so it is essential to check the intonation up to the highest played fret.

 

I fail to see the point of checking each fret for intonation. If you set it right at the 12th fret and it's sharp at the first, what do you do? If you adjust it to be right at the first it will off at the 12th.

All intonation is a compromise. Thre's a lot goes into intonation depending on whether you are playing mostly in one key, in multiple keys, on your own or with other instruments. We don't need to go into all of that here, but suffice to say that if you set the intonation at the 12th fret properly you will have as good a compromise as any.

 

It causes some of the frets to be closer together than they otherwise would if the the neck was straight, the more relief the more some of the frets will be forced closer together, so technically, yes it would, it's how physics works, also look above to see why you otherwise are wrong.

 

With the amount of relief we are talking about, the difference in fret spacing would be in the billionths of a micrometer. not in the least significant. A speck of dust on the fret would have a larger intonation impact.

 

I stand corrected, still technically it would be true, and explains why it was not an unreasonable thought OP had when he mentioned relief to possibly having an effect on intonation.

Sometimes people seems more interested in proving how they are more knowledgeable than the person asking for help than really being helpful (not aimed at you, as you actually answered the OP to what he asked, but certain other people replying in this thread).

 

Historical perspective:

The first bass guitarists came over from the double bass. "Low action" was not something they were looking for. They were pulling HARD on the strings and they demanded absolutely no rattle. The old guys used to tell me to raise their strings, not lower them. Today's players would consider their instruments to be unplayable.

Same goes for the electric guitar. Those guys were coming over from acoustics and big jazz boxes. Again, they strummed and picked hard. They didn't want any rattle and were used to (what we think of today) as high action. Furthermore, no one was playing light gauge strings until the late sixties and early seventies because they weren't (invented!) available until the mid sixties. These guys weren't playing "nines" or Super Slinkies. Their string sets were 13-56.

Another thing to consider is that fretwork was less precise then than it is today. Discounting the fact that most factory made guitars could be improved by a good fret dress, it wasn't a problem because no one was demanding 3/64" string height at the twelfth fret. Just like today, these guys wanted good tone and that meant no rattles. They weren't covering up the noise with a Big Muff Pi. Cleanliness ruled the day.

So when looking at history, it is a good idea to find out what was considered normal or industry standard to put things into their proper context.

By the way, guitars do not need more or less relief than basses. All things being equal, it is the string and it's vibrating pattern (excursion) that determines the minimum relief. Practically it's pretty much the same. Start the set up at .012" of relief and fine tune it from there.

 

Because you have to account for how the owner plays the instrument. A heavier hand requires more relief, a light touch less. And it also depends on the instrument's behaviour. Once of my basses works best with relief set at .012, another at .008.

 

Me too, it's excessive, and i didn't recommend that. Checking every 3rd fret is probably enough

If the open note and 12th fret are in tune but the 1st fret is not, this is an indication of a nut slot cut too high or too low, or the witness point not being set, or maybe the nut being placed at an unsuitable 'compensated' position.
In this case you would have to compromise: open note and 1st fret slightly out in opposite directions.

In this case it is possible to intonate all the frets but then the open note will be out.

Not so for 2 reasons:
1. Because you are setting saddle position according to only 1 data point instead of many frets up to the highest played fret. With more data you can choose a better compromise saddle position.
2. On the higher frets, a particular amount of saddle movement is a larger proportion of the vibrating length, so results in a larger change of pitch, so the intonation of higher frets is more sensitive to saddle position. So if you set saddle position by only checking the 12th fret and get the 12th fret fairly well intonated, the higher frets can have larger errors. Checking the intonation of the highest played frets is therefore how you 'fine tune' the saddle position.

Absolute stated measurements are irrelevant and unimportant because you set your action as low as you can according to your needs, it will be different for everyone.

Yes, these stated measurements are just very rough suggestions as starting points, and far too much importance is placed on them. Players should not set up their action to a stated measurement, because it will almost always be wrong for them.

 

I agree wholeheartedly that it’s irresponsible to suggest that any given set of parameters is right for any given player. OTOH, there is a limit to what is reasonable. .25 is excessive. And in my books so is .021. In over 50 years of servicing guitars and basses, I have not encountered a single player/bass combination that required that much relief.

Edit: I have encountered the need for more "relief" than .021" on a double bass. But never on an electric bass guitar.