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I've got n-Track Tuner and Strobosoft on my iphone, and have used both to tune my acoustic guitar, but am not sure if this is the way to go to check intonation?

The reading never seems to settle down long enough for me to feel confident that the notes are x-cents (or a fraction) over or under.

(For that matter, I'm not sure how many cents off a note has to be either at the saddle or nut to really warrant concern? Assuming you're not cursed with perfect pitch.)

Both apps are obviously fine for a simple tune-up, where close enough is fine, and both seem to settle down for a longer period of time (maybe a full second of time) if the note being played is ON, whether it's an open E on the first string or a fretted E on the fourth string, but boy if the note is over or under it's more like watching a slot machine.

Any thoughts?

Hi ya Dennis. Shortly after Peterson launched StroboSoft for the iPhone I had the app and started using it. We have a big-arse Peterson bench unit and I checked the StroboSoft app against it's bigger brother and it was spot on....

Since then I have set up thousands of guitars and other stringed instruments including setting intonation with the Peterson StroboSoft IPhone app. It works very well and if you can't get it to settle down long enough for you to get a hard reading there may be actual issues with the instrument that cause the inconsistencies that you are seeking. For example a nut slot that is cut too shallow for the break angle can permit the vibrating wave of a string to breach the nut slot face as the wave travels into the nut slot. This will throw off the readings and needs to be fixed before setting intonation.

As for setting the intonation you can go for actual readings or you can go for the strobe display stopping and not rising or falling. When the display is near static for both the fretted note and the overtone you're there.

We human bags of mostly water (Star Trek fan with arrested development here.... ) it's been said that we can hear variance of 4 cents or more. Of course this also is dependent on our age, how well we hear, and maybe how long it's been since bar night.... too. When I set intonation I shoot for accuracy of a couple cents or less. If it's true that most can't hear better than 4 cents variance this should do the trick and so far no complaints either.

Hope this helps.

I dunno about most people, but to my ears 4 cents off is a glaring difference. I shoot for +/- 1 cent on a new guitar. Old funky guits might need to settle for less precise...

My stupid phone has no problem hearing the 12th fret harmonics with any tuner apps i've tried. I agree with the previous post; it's either something wrong with the guitar setup, or possibly your technique. Is it having trouble hearing the harmonics, or the pressed down 12th fret notes, or both?

Maybe I spent too much time at a G*itar C*nter on a busy Saturday and it damaged my hearing.....

To be more specific I shoot for .000000345873 cents or less but I also know that as soon as someone changes brands of strings all bets may be off..... Kidding of course.... somewhat....

Said it before and I'll say it again.........." A good ear is a blessing and a curse".
Tom

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A person who has never made a mistake has never made anything!!!

Dennis, try plucking the string in different places. I find I can get better clarity at some points more than others.

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Doug

Don't let fear or common sense stop you from trying to build something

A strobe tuner is the next best thing to an ear. I don't have any experience with "apps", but I have an old-school Peterson strobe tuner that I find useful occasionally. Don't expect the display to be constant over time. Notes change pitch as they decay. Don't expect all the partials to sync. Some strings are inherently
inharmonic. (The G string is notorious, but body resonances can make any note problematic.) If you see a particularly "fuzzy" display, you probably have a note that is close to one or more body resonances.The best solution is to trust your ear, or trust the ear of someone you trust. Piano tuners still use their ears. Good ears still trump strobes and "apps".

One a brand new guitar , You need to plan for a bit of movement. If you set up so your intonation point is too far back on the saddle , as the top flexes and the bridge rotates you can actually end up shape. I like to be 2 to 3 cents flat on the initial set up. In about a month the top will come in from the load of the strings.
As action rises it goes sharp
as the bridge rotates the saddle will move forward causing intonation to go sharp so plan for that from the get go.
Depending on the saddle thickness you are using the more critical this point will be. On a 3/32 saddle and my brace I know that 2 to 3 cents falls in well for me. On a thicker saddle you can allow more fudge room. You can get amazing good intonation if you take your time.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

the paid version of ap tuner for android works very well

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MK5acoustics.com

I guess I wasn't clear. I'm just saying to my ears 4 cents is quite obvious, and even 2 cents is a clear difference.

Actually I agree with your post 100%. Shooting for an accuracy of "a couple cents or less" sounds exactly right for repairs, factory guitars, etc. Of course shoot for .00000654 cents if possible...

I have not done thousands of setups like you, but I did quite a few in my musician days, when I often got stuck fixing all my 'friends' instruments. +/- 2 cents would be very optimistic for much of what's out there, to say the least. And, as you say, as soon as the strings change or start to wear out, all bets are off.

It's funny you're the first person that I've heard mention this. This is definitely true. I always set up new instruments to intonate a bit flat, and go back a month later after the guitar has squeezed itself together a bit and check it again, adjusting as needed.

Thanks for all the replies. I haven't had a chance to get back to this yet, but plan on doing so this weekend.

It's probably just operator error.

I have the iStrobeSoft app. But I've done a lot of electric guitar setups with standard chromatic tuner and it served me sell. The player was happy about the good intonation too (it was really off at first).

I can't get iStrobeSoft to work with electric guitars because the string is too quiet for the iphone mic to pick it up. So I had to plug it into an amp and use that sound as reference.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Peterson, the developer of StroboSoft also sells an adapter cable that plugs into the IPhone headphone jack and provides a 1/4" plug for electric guitar cords. No amp required. I've used this adapter for about 7 years now and it works great.

You can also get a clip on extension for if you tune acoustics. This may help from being so jumpy. It's a 1/4" jack but I suppose you could get a 1/8" adapter.

http://www.amazon.com/Peterson-TP-3-Tun ... y_MI_img_y

I use the StroboPlus HD and just love it. I like it so much I have started taking it out to sessions and gigs. Very accurate and responsive with a big screen that's easy to read.

http://www.amazon.com/Peterson-403867-S ... r+peterson