Author Topic: Intonation (Read 450 times)

wayne · « **on:** April 11, 2011, 08:24:15 PM »

OK, I know there've been several threads about intonation, but I don't recall reading about the issue I'm having.

Background: Strings are not old, but not brand new either. I have followed Brother J O E Y's setup routine to a T and have low action and - as far as I can tell - a straight neck.

Problem: The intonation isn't intonating.

The G string is not right. At the 12th, the fretted note is flat from the harmonic. I've measured the distance from nut to saddle as accurately as I can - it's dead on 34 inches.

The D string is totally wacky. At the 12th, the notes match. The upper octave is flat. The lower octave is sharp. This with the saddle the same distance from the nut as the G string.

I'm afraid to seriously check the other strings. :-)

Now, could this be a string thing? Could they be false? Could they be not setting properly in the nut or saddle? Could my new tuner just be too darn sensitive and accurate (+/- 0.02 cent)?

I've never seen the G string be out when it's set at 34 inches - unless the action is so high you're bending the note fretting it. I've never had to make the D string length shorter than the G.

I'm at a loss. I don't want to just blindly change strings without being reasonably sure that'll fix the issue.

All comments and help is greatly appreciated!!

Thanks y'all!!

C-Ya...........wayne

adriaan · « **Reply #1 on:** April 11, 2011, 11:43:33 PM »

Wayne, you say the G string is flat at the 24th fret. Is this the reading you get on the tuner, or is this your ears telling you it's flat? I usually check by playing some chord inversions with an open E string, finishing with the A string fretted at the 23rd, and D and G at the 24th. All chords should be nice on the ears. Perfection is impossible (ever heard a piano tuner at work?).

mario_farufyno · « **Reply #2 on:** April 12, 2011, 06:33:56 AM »

Wayne you can't expect that a string will be really in tune at 12th fret just because it has exactly 34. It didn't work like that and this is why you must have to be able to move saddles.

Don't use a measure, use your ears.

Don't expect a place it should be, find the place where it must be. There is no fixed rule about how long a string should be compared to others.

Listen to the 12th fret harmonic and compare it to the fretted note. If it sounds flat, you must shorten the string moving its saddle towards the Neck. It doesn't matter if this not turn to be exactly 17 inches (half 34) - if so, all saddles should be in line and this simply doesn't happen.

If have room to move saddles, keep moving until you find the right spot. After adjusting intonation at 12th fret, go check upper harmonics like 24th fret harmonic with 19 fretted note at higher near string. Just when everything is Ok, go check 24th fret (you don't need to use tunners, there are other harmonics you can use to check other notes/positions at the Neck).

mario_farufyno · « **Reply #3 on:** April 12, 2011, 06:50:24 AM »

There are few causes I can imagine if a String can't be correctly intonated at 24th fret and 12th fret simultaneously:

- bad string
- warped neck
- bad fret job
- error induced by tuner

I really doubt there is a single Alembic with bad fret job and, to be honest, there is no much chances that a Neck made like Alembic does could be warped. So we end with problems on strings, there must have a reason to the warning of always intonate with brand new strings (remembering that any string older than 1 month is already considered old), or may be occured a misreading from electronic tuner. Not you, machines can fail.

I really don't trust them more I trust my own ears. As it is really easy to hear beating with strings sounding not at exactly same frequencies, there is no good reason to use one. You must just be carefull when fretting notes to not bend string a little, but is really easy to compare a fretted note against one harmonic.

Anyway, if you ears tells you it is correct, you don't need a neddle or flashing light to tell you the opposite. The problem seems to be excessive confidence on tuner when you should use your ears (you will not play music for it or any machine, you will be playing for people).

cozmik_cowboy · « **Reply #4 on:** April 12, 2011, 06:58:37 AM »

As others have said, you can't measure. 34 is your starting point; you have to adjust from there. Use a strobe. Electronic tuners, be they a $400 Korg rackmount or a $20 IntelliTouch, are accurate to plus or minus 1\ cent. Strobes will get you 1/10 of a cent.

Peter
p.s. - Hey, moders, how come my alt+10-key codes aren't working on the board anymore?

cozmik_cowboy · « **Reply #5 on:** April 12, 2011, 06:59:17 AM »

As others have said, you can't measure. 34 is your starting point; you have to adjust from there. Use a strobe. Electronic tuners, be they a $400 Korg rackmount or a $20 IntelliTouch, are accurate to plus or minus 1 cent. Strobes will get you 1/10 of a cent.

Peter
p.s. - Hey, moders, how come my alt+10-key codes aren't working on the board anymore?

mario_farufyno · « **Reply #6 on:** April 12, 2011, 07:02:54 AM »

I use a tuner just to help tuning open Strings. Don't forget you must retune every change you do at saddles. As a string can stuck in saddle is good to loose it and tight it again every time.

mario_farufyno · « **Reply #7 on:** April 12, 2011, 07:19:24 AM »

I use the 12th fret Harmonic to check intonation at a upper string 7th fretted note. Then I use the 12th fret Harmonic to check 17th fretted note at lower string. After that I use 24th fret Harmonic to check upper string 19th fretted note and 21st fret sound at higher strings (like the octave between E and G or the fifth between E and D) and end checking 19th fret Harmonic against 24th fretted note on lower string.

There is always some usefull harmonic you can choose.

Note: use lower harmonics, some of the highest partials can be raised or lowered compared to tempered scale.

(Message edited by Mario Farufyno on April 12, 2011)

terryc · « **Reply #8 on:** April 12, 2011, 07:45:35 AM »

Wayne..I assume you own an Alembic but if you don't there are a couple of things you can add to everyone's suggestions.
A similar experience happened with me many many years ago and I discovered that the string was sticking in the saddle grooves so check there is no burrs which can impinge on the windings, if so remove gently with a round profile fine file, this can also occur at the nut. I know it sounds stupid but if a bass has had many years of roundwound strings on it it will emboss the winding profile into the nut/saddle material.
Also apply a spot of very light machine oil on the saddle and nut grooves(if brass) or use graphite powder on a bone or plastic nut.
This was a common occurence on Strats where the EBG unwound strings stuck in the nut after a generous use of the tremolo.

bigredbass · « **Reply #9 on:** April 12, 2011, 02:31:09 PM »

I would never attempt to set intonation with anything other than utterly brand new strings. It's just too easy for organic contamination (you, chicken grease, etc.) or the windings shifting, etc., to pull off your readings. Magnetic pickup interference is generally not a problem with bass pickups, though I have heard of guys having them high enough that they'd gain a 'false fret' on the pickup shell if they played waaayyyy up the neck . . .

You say you're satisfied you've done the setup properly, so you have no obvious string rattle, fret interference that's audible, your heights are correct, and so on. So I'd reasonably expect there's no obvious problems on that front.

There will always be a disconnect with striking the compromise mathematically that a 'tempered' tuning requires. THAT discussion requires big-brain-processing that's way past me, except to acknowledge it since some guys and girls can just hear where it's 'off' even when everything is exactly right under this format we all work under. Having worked with more than a few pedal steel guitar players (the ultimate fretless instrument) who have to deal with an instrument that when they raise or drop notes, those also have to be in tune, and the great-ears players learn to live with the oddly in-tune/out-of-tune reflex it engenders.

I CERTAINLY don't have ears like that. I could never adjust intonation by ear, and if you can, I'm amazed. I always have to do it by strobe tuner. You can get really fussy about it, do your match/comparison adjustment at the 12th, then the 24th, etc., out several harmonics if you feel better about it that way. I would not approach it from the standpoint of measuring string lengths from a rule. I believe you could do that IF you were using four single wires that were identical: Add in different core sizes, different wrap diameter/ tensions, it would take lots of geometry to find out the optimum string length for a given scale. Use your tuner !

Remember also, identical string guages from different sets will adjust differently to be in tune. A 45 G from a roundwound RotoSound set is a different animal from a 45 G from a different brand, or even another 45 G from a different RotoSound product.

In a practical sense, I've never worried a whole lot if they were out just a bit: I never played chords on a gig(!) and I could never tell I was 'off' to the rest of the brand. So I'd advise play what you got, run them through a strobe and intonate them as best you can for now, finish the strings you have on. Then when you do change strings, you get it right at that time.

It's like instrument flying: I can't trust my ears, I have to trust the instruments (my faithfull BOSS tuner).

J o e y

bigredbass · « **Reply #10 on:** April 12, 2011, 02:41:30 PM »

So I wandered off into FogHorn LegHorn mode and forgot the important question: Do you know HOW to tune your string lengths with an electronic tuner?

Tune your bass.

Hold it in your lap or on the strap. Just like adjusting your neck, DO NOT do this with the bass laying on its back on a table.

Compare your 12th fret chime/fretted note. If the fretted note is flat, screw your saddle towards the nut. If it's sharp, run it towards the tailpiece. You will have to retune as you do this. They will eventually match and you're done.

(IF you're playing a 'more-that-four' string bass, you may find you've barely got enough travel to reign in your B, or F#. Really need to consider larger-travel bridges in the design departments . . . )

J o e y

mario_farufyno · « **Reply #11 on:** April 12, 2011, 04:42:19 PM »

Joey, to trust your ears again try this:

- Tune your Bass with your Boss Tuner,
- now play open A string while fretting E string at 5th fret
- Then slightly tune down the A string...

Can you hear volume oscilating?

Note that this effect will speed up if you keep tuning A string down. It is called beating and is the result of the increasing difference between string tuning. So, if you tune up A string again, the beating will slow down and stops when it gets exactly in tune.

It doesn't matters if they were tuned by fork or eletronic tuner, if you compare 2 strings and get no beating, they are at same pitch (frequency). And I'm pretty sure you can hear when beating is going on or not.

You don't have to hear in perfect pitch (absolute hearing) because it is physics, the interactions between 2 different close frequencies will always make their sum oscillate intensity.

So, you can trust your ears and can easily intonate. You just have to check fretted notes against harmonics.

(Message edited by mario farufyno on April 12, 2011)

mario_farufyno · « **Reply #12 on:** April 12, 2011, 06:36:02 PM »

Tune in, turn on...

wayne · « **Reply #13 on:** April 12, 2011, 09:02:18 PM »

Lots of great info here guys. I truly appreciate it.

Things that I didn't think of. Things that I know but forgot about. And things that I've known and used for 30 years that I did check and forgot to mention in the original post. I'm satisfied there's nothing hinky with the Unicorn, it just needs a new set of strings and inspection for grooves in the saddles.

Maybe I need to just stick with the fretless and stop worrying about Equal Temperament.

BTW - If you're looking for a new tuner that's REALLY accurate and the freaking most sensitive thing I've ever used, try the Sonic Research ST-200.

A fellow Alembic player here that gets into and understands the tech-stuff behind these things is satisfied with it in place of a Peterson Strobe ($130 vs. whatever a Peterson runs these days).

C-Ya................wayne

[And Brother J O E Y, wander in Foghorn Leghorn land all you want. If it's not educational or enlightening, it's always entertaining!]

bigredbass · « **Reply #14 on:** April 12, 2011, 10:58:02 PM »

Mario, I can hear the beats, my problem is once I get REAL close, I can never quite make out when I got rid of all of them !

I once played in a band with a guy with perfect pitch, and I'm convinced it was a curse and a blessing for him. My piano teacher's wife also had perfect pitch, and the scaled tuning of a piano (A below middle C pefect, then the tuning went progressively flatter as you headed into the low end, progressively higher as you went to the top of the keyboard) could actually give her a headache if she could not 'buffer' her hearing in her mind.

My ears are not that good, thankfully, so I just strobe out.

Tuning is one of those 'bottomless' subjects, but I can tell you the BEST advice I ever got was to always tune UP (in other words, never go sharp and ease back down to pitch when tuning) as it 'sets' the keys against the tension: Even the best keys can back off a little if you tune down.

It's one of the three things I have to have in a bass: If it won't stay in tune, if it's noisy electronically, and it can't be made to play easily, whether it's a $100 pawn shop axe or a $10,000 custom, I don't want it.

J o e y