Jackson scale length anomaly?

[Newc]

Ok, I know Jackson uses the occasional variant scale length (like for the Swee Tones - 25"?) but generally they use 25.5" and 24.75", right?
So how come my Grover Jackson AND Jackson Pro Roswells are 25 5/8"? [img]graemlins/scratchhead.gif[/img]

It's 25.5" to the front edge of the TOM, but the saddles (intonated correctly) are between 25 5/8" and 25 11/16" [img]graemlins/scratchhead.gif[/img]

On all my others, there is at least one saddle that is dead-on the 25.5" mark.

Newc

[Black Mariah]

Re: Jackson scale length anomaly?

scale length != proper intonation

It's all in the strings. The scale length is only important as far as fret placement goes. When you place the frets you COMPENSATE the distance at the bridge to achieve proper intonation for your string gauge.

If you continued the frets up until they were next to the bridge, you would NEVER get it properly intonated. The closer a string gets to one of the breakover points, the higher the tension needed to push it around. The higher tension wreaks havoc with intonation. Since playing up close to the bridge is rare outside of slide guitar, where intonation is iffy anyway, it's best to relegate the discrepancies to the end of the string where it won't be noticed.

I really hope you can make some sense of that. DAMN, I NEED SLEEP! [img]graemlins/laugh.gif[/img]

*EDITED to remove some confusing crap

[ October 09, 2003, 01:23 AM: Message edited by: Black Mariah ]

[Genebaby]

Re: Jackson scale length anomaly?

Seems straight forward to me Mike, good explaination.

[ranalli]

Re: Jackson scale length anomaly?

Black Mariah's got it dead on.
Good explanation.

Has anyone ever had a set of strings that would not intonate on their guitar before?? I had a set of cheaper strings that just were a no go....the saddles wouldn't go back any further. They were cheap strings but I figured I'd give em a try.

[WAR IN D]

Re: Jackson scale length anomaly?

Yup, I traded an AT-1 to a guy here not too long ago that had the Wilkinson (I think) TOM type bridge on it, the one that has the funky G/B string intonation adjustor on it.. I had it strung with 9/46's and never had a problem with it intonating properly, he got it home and put a different guage/brand of string on it and when he went to tune it.. intonation was off and he couldn't get it come back.. He emailed me and after all the ideas I had were exhausted, the only possible explaination left was the strings.. I told him to go get another set and try it out. Fixed the problem right up, only thing was.. he was using good strings to start with. So it's not only limited to cheap strings it would seem. The chances are probably better with high quality strings, but I guess it can still happen.

[yabba]

Re: Jackson scale length anomaly?

because of exactly what Black Mariah said, I've always been told that a better way to measure scale length is to measure from the nut to the 12th fret and then multiply by 2.

[Chuckracer]

Re: Jackson scale length anomaly?

Um...why? You wind up with the same number.

[Number Of The Priest]

Re: Jackson scale length anomaly?

I've also been told that the "formal" and "proper" way to determine scale length is to measure from the start of the speaking length of the string at the nut to the 12th fret and then multiply by two.

Chuckracer asks why. Let's say you own a 25" scale guitar like a Carvin. My best guess is that if you properly intonate that guitar by shifting your bridge saddles appropriately, it's highly unlikely that the actual string length falls exactly on 25 inches. On the low E string and G string, they may get longer, deceiving you into thinking you have a 25.5" scale guitar, and on the D string and high E string, they may get shorter, deceiving you into thinking you have a 24.75" scale guitar.

Okay, saddles don't really move THAT far, to my knowledge, but not all the strings perfectly land on the true scale length of a given guitar, whether it is 24.75", 25", or 25.5".

[Newc]

Re: Jackson scale length anomaly?

Yeah, but the end of the bridge's base is smack on 25.5" - the saddles do not get near it. On all my others, the low E is perfect on the 25.5" mark, and the other 5 saddles work from that point, but the Roswells START on 25 11/16" and run to 25 5/8".

Newc

[straycat]

Re: Jackson scale length anomaly?

Aren't you supposed to measure the scale length from the take off point at the nut to the string saddle of the "D" string?According to Dan Erlewine's books thats the way to do it.

[yabba]

Re: Jackson scale length anomaly?

Chuckracer: the explanation I've heard is based on what Black Mariah said; scale length has more to do with fret placement than bridge placement, so by measuring from nut to 12th fret, you're talking the bridge out of the equation. (although obviously the bridge placement is important as well).

[JACKSONFREAK]

Re: Jackson scale length anomaly?

As I understand it. The 12th fret should be exact middle of the distance from the nut to the bridge saddle break point. Then the rest is in halves from there for fret placement. Yes with the bridge in a different spot the center for the 12th fret would change. But all things being the same it seems that Jacksons do have a different placement. My Jacksons trems meet the 25.5 mark at the very base of the bridge plate. Then the saddles are farther back from that. Yes that too can be a scale length but then why advertise it as a 25.5" scale length when its 25.5/8"?
Gil