# Are 9 string guitars worth it?



## johnpyeatt13 (Jan 10, 2016)

I'm just curious because I kinda wanna try one out. I'd probably buy an agile or something like that just to try. Do I need a bass amp? I use a Mesa Boogie Mark V 25. Could I just use an eq pedal or the VFE Focus to try it out? I mainly use a 7 string, but I think it would be interesting to just try one out. Maybe I should look at an 8 string. What are your guys' thoughts? Also I would definitely change the pickups. I am not a fan of actives.


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## lewis (Jan 10, 2016)

johnpyeatt13 said:


> I'm just curious because I kinda wanna try one out. I'd probably buy an agile or something like that just to try. *Do I need a bass amp*? I use a Mesa Boogie Mark V 25. Could I just use an eq pedal or the VFE Focus to try it out? I mainly use a 7 string, but I think it would be interesting to just try one out. Maybe I should look at an 8 string. What are your guys' thoughts? Also I would definitely change the pickups. I am not a fan of actives.



 not sure if serious or not?

The VFE Focus would work great (i own one too). the Mark V being boosted by a pedal from a 9 string sounds awesome to me.

What bands/tuning have you gasing for a 9?. Im happy on 8s personally


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## LX_T (Jan 10, 2016)

Ask yourself: Do I really need a 9 string?
Probably not. If you need a 9 you would know it for sure.
Go to a store, try one out and see how it suites you. Don't waste your money.


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## Winspear (Jan 10, 2016)

LX_T said:


> Ask yourself: Do I really need a 9 string?
> Probably not. If you need a 9 you would know it for sure.



I use 9s and yeah I'd say this is probably true. If you don't feel a need for one then probably don't buy one. But certainly try one out if you can!

No you don't need a bass amp - the basic setup and tones are just the same as for 7s or even 6s.


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## AlexThorpe (Jan 10, 2016)

I still really badly want to pick up a 30" 9 and tune it fourths BEADGCFBbEb and have a bass/guitar hybrid tapping/looping monstrosity.

As far as it goes for a metal context, I could tune my 8 down if I really wanted to go that low and not miss much in context with what I play.

If you have the cash or can find one used, why not?


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## Emperor Guillotine (Jan 10, 2016)

LX_T said:


> Ask yourself: Do I really need a 9 string?
> Probably not. If you need a 9 you would know it for sure.
> Go to a store, try one out and see how it suites you. Don't waste your money.


Benefits to more strings: it will make your d*ck look bigger online - until people realize that you really don't know how to even play the thing. Don't fall victim to the "not enough strings" notion that has become overhyped online. Like LX_T said: if you need a 9, you would KNOW it.

I really doubt that the OP will be able to find a 9-string guitar sitting around at a store nowadays since the market is still so small and so niche.

I currently have had a 9-string for a year. It has been played maybe three or four times max. I just don't see the need for it at all. (Because I haven't been playing it, I've never gotten around to doing a NGD thread to post on here.)


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## Konfyouzd (Jan 10, 2016)

Most ppl I see w 9s either only use the lowest string or they seem to be forcing themselves to use every string on every riff seemingly only to justify their decision.


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## Hollowway (Jan 10, 2016)

For me, an 8 string is the perfect instrument. The 8th string is super low, but still sounds great, and doesn't feel too thick, is useable musically, etc. A 9 string, however, with an extra low string, doesn't feel as natural to me. I have 2 instruments, and for me the notes feel so low that they sound substantially different than the other strings. It's quite possible that with a longer scale length than 30" they'd feel better, but idk. Currently I'm ordering thicker strings for the 9th string to see if increased tension makes it feel more natural.
But for you, it really depends on how you get along with it. Tough to find them in stores, though!


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## MoshJosh (Jan 10, 2016)

What if I told you, that for the price of a 6 string guitar you can now get not 1, not 2, but 3 extra strings!!! No brainer

But seriously I think it comes down to, are you gonna use all 9 strings? Do you need 9 strings to create the music you are trying to create? Or do you have some money to burn and are you ok buying a guitar not knowing if you like it or not?


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## Alex Kenivel (Jan 10, 2016)

After playing and getting used to a 7 for a half a year, I discovered the role that the 8th string could have as far as completing a scale a whole octave lower. It just made complete sense to me and there was no doubt in my mind that I wanted an 8.

I didn't have that revelation even once after playing an 8 for almost two years.


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## Chokey Chicken (Jan 10, 2016)

You don't need to use all strings frequently to justify it. What do you crave musically? Guitars playing in the bass register is a unique and nice sound. You can play it with 100% tapping, or it could just be a versatile axe. Record sorta bass lines, loop it, record rhythm, loop it, then shred the .... out of the high register without putting the guitar down. Maybe you'll just like playing 6 or 7 string stuff on a super wide neck. Who knows! Thats the best part about creativity. There's always something new to try. I say go for it since you'll never fully know what you think until you try. Don't let people get you down making fun of your lack of use or overuse of anything. Do what feels good to you.


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## jephjacques (Jan 10, 2016)

9 was too many for me but different strokes for different folks


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## Counterspell (Jan 10, 2016)

Hey man, it may be a challenge to get your hands on one to demo, but it's worth it if you can check one out before you buy. I never knew I wanted a 9 until I got to try my buddys Agile 930. He was selling his 2228 since he moved up to the 9. I went to his place to check that Ibby out, but once I jammed on the Agile for a few minutes, I knew that it was something I really enjoyed.

I would say, don't view it with whatever stigmas or bias may be attached to it. It's an instrument. It's a tool to create art. Consider the options it will make available to you concerning tuning and scale length ect, and decide if those are opportunities you would be willing to explore. Good luck man!


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## blacai (Jan 10, 2016)

I wouldn't spend too much if you don't feel the NEED of playing the 9 string range.

But GAS is GAS. I bought my 8's because it looked gorgeous and after playing it 15min during the musikmesse I felt it would serve perfectly my musical tastes, although I really have no clue how to "play" it properly


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## GunpointMetal (Jan 10, 2016)

You might like it, especially coming from a seven string. I bought my nines (yeah, I got two at the same time, because I knew I would be writing with it a week after it came out of the box, which meant I would be playing it live, which meant I needed a backup) and its been loads of fun. I play my nines like a seven in drop A w/octave-down E and A strings, running a 124 for the low A (soon to be a 118, 124 is a little big). If you think you can use the low end (even if its just for brootal chug downs, screw the haters) I say go for it. I play my ERGs like six strings with extra strings in the middle, and I'm sure a lot of people would say "You don't need nine strings for that, just tune down"....whatever.... I still want to be able to play everything I can on my 6 and 8 string guitars, and still go lower, so I got a nine. I have a band right now that probably uses the high three strings twice in 7 songs, but I wouldn't have those options on an 8. 

TLR; DO WHAT YOU WANT, MUSIC IS WHAT YOU MAKE IT.


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## Konfyouzd (Jan 10, 2016)

I see them being really useful for 4+ finger tapping stuff--even 10s. It'd allow you to use the same note for a chord as a note that you're using for a lead while still allowing the chord to ring out. Doing it with less strings might end in such a way that you cause one of the notes on your chording hand to stop ringing out. But for regular playing I really haven't seen anyone do anything impressive yet. I'm surprised no one has posted any videos yet.


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## blacai (Jan 10, 2016)

Konfyouzd said:


> I'm surprised no one has posted any videos yet.


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## Grindspine (Jan 10, 2016)

I have several six strings, two sevens, and play eight string guitars pretty frequently. At this point, eight stringers are a challenge, but I have really gelled with a few of them.

Nine strings on the other hand, I have played only a couple of times, and those times they felt so awkward. As was previously mentioned, the lowest string's tension is so much lighter than the other strings.

Unless you're using two hand tapping techniques, it is really hard to make music out of a nine. The only exception to that I know is Justin Lowe of After the Burial, but he passed away shortly after getting a grasp on playing nines.


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## trem licking (Jan 10, 2016)

9 strings aren't something you need, it's something you want. if you're not sure if you want it try it out... but usually people that crave that much awesome have a hunger for it. the only thing stopping me from 10 strings is the lack of ambition to mod the guitar to make it work (ie make bridge hole large enough to accommodate a string necessary to hold a G#0 at my desired tension)


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## johnpyeatt13 (Jan 10, 2016)

I appreciate all of the replies. I'll probably go to gc and play some more 8s and get a cheap one I can upgrade thr pickups on.


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## Konfyouzd (Jan 10, 2016)

That Tosin video was cool. First time I've seen something musically interesting done on one.


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## Emperor Guillotine (Jan 10, 2016)

Grindspine said:


> The only exception to that I know is Justin Lowe of After the Burial, but he passed away shortly after getting a grasp on playing nines.


All Justin did was 0-0-0-0-0.

Mike Gianelli on the other hand shreds on his 9-string. He has videos all over Instagram, Facebook, YouTube, and EMG TV.


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## PBC (Jan 10, 2016)

^ the EP he put out this year is great. You can stream it it on Mike's bandcamp. 

Although you're milage may vary, 9 strings made sense to me when I thought about my "tuning center". 

8 strings, like stated above, almost complete 'standard' tuning in a way. 

Common Tuning from Low to High:
EBEADGbe

For me, extended range guitars feel like they need to be in both directions; adding a high string and a low string. This can be done on an 8 string. 

I play predominantly in C# and am going to get a 9. When envisioning a nine, I see 

From low to High:
C#F#C#F#BEg#c#f#

Allowing me to approximate a dropped 7 string for some writing while alternating between octaves for my 6 string riffs. I think of it as a chapman stick, extending from the middle strings for emphasis on certain parts. 

e.g. A standard:
DADGCFadg*

Because of the soft barrier of the "lower interval limit" (from berklee). The lowest I would tune the 9 would be 

BbFBbFBbEbGCF or BbFBbEbAbDbGbBbEbAb*

_*multiscale needed_

If your location is correct. Certain Guitar Centers might carrier an RG9 you can try out, (which is how I fooled around on one).

The Schecter C-9 and the Ibanez RG9 both have a 28". Schecter also makes a 30" one if you don't mind bats on your guitar. 

If you want to try those stretches in the Guitar Center, a Dan Electro 56 Baritone (which they have in stock) has a 29.75" scale or grab a bass and treat the 2nd fret as the nut. Meaning 3rd bass fret = 1st fret of 30" scale ect. 

Lastly, I would agree with what's been said above in the words above. If you don't feel the hunger, then you probably don't need one. 

tl;dr: Completing that dropped/perfect-fifth octave and adding an extra high feels like 
a perfect ERG for me.

Good luck.


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## Zalbu (Jan 11, 2016)

Konfyouzd said:


> I see them being really useful for 4+ finger tapping stuff--even 10s. It'd allow you to use the same note for a chord as a note that you're using for a lead while still allowing the chord to ring out. Doing it with less strings might end in such a way that you cause one of the notes on your chording hand to stop ringing out. But for regular playing I really haven't seen anyone do anything impressive yet. I'm surprised no one has posted any videos yet.




This is the best video I've seen for a 9 string so far. I like some After The Burial stuff they play on 9 strings too but that's more in the djenty-chuggy territory. His tone in this video makes it sound like he's playing on a rubber band though, but I feel that it actually fits pretty well and give loads of clarity to the C#.


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## Great Satan (Jan 11, 2016)

Anything over 8 strings just looks like a lute lol

None of these videos posted so far have sounded like something i'd actually want to, y'know, 'listen' to..


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## gujukal (Jan 11, 2016)

Im pretty sure u need some long ass fingers to even found a 9-string comfortable to play. I htink most people would just found the neck to be too wide, especially when playing on the 9th string.


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## Bearitone (Jan 11, 2016)

To the OP.
If you just want to try some super low tuning on a guitar that intonates well and offers proper tension for very low tuning I suggest you check this out:
Guitars : Hellraiser C-VI

Its a 30 inch scale beast that will you play Drop E and lower with no problems at all. Pickups will be easy to find.

You can also go the agile route and get 30" scale 7, 8, 9, or even 10 string.

My point though, is that the 30" scale length is what will allow you to tune super low. Not extra strings.

But by all means, get whatever you want and don't let anyone try to trash-talk you out of it. I love my 6, 7, and 8 string guitars.


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## Halowords (Jan 11, 2016)

I may be the odd man out here, but to me...Yes!

My first ERG/>6-string/whatever is my recent Agile 92730 Septor (which I still need to take pictures of and post a review). I suppose it had to be that or a Chapman Stick or the like. I will agree that an 8-string may be pretty much perfect for a lot of people and the 9th string from the factory is worthless. However...once I get a tighter string I can see where I can use the 9th string for low notes or playing stuff higher up the neck. I find myself reaching for said 9th string quite a bit but it buzzes too much to actually use. So better strings (tension-wise and whatnot) will definitely help quite a bit. How much will I actually use the 9th string? Who can say? But I suspect I WILL use it. More on how down below...

Neck and scale were surprisingly natural after a pretty short time. And I would note I have what would most likely be considered average size hands and fingers, maybe a bit on the short side. Barre chords on the first fret can be awkward with the fan but that problem seems to have dissipated for me, and I could not effectively barre across all nine strings but I also see no reason why that is an issue, but playing with my thumb on the back of the neck in a classical style I can reach everything pretty fluidly if I do say so myself. To me, while playing it, it's an extension for the scales both up-and-down the neck, and across any particular fret. I have not done much with extending chords to 7th or 8th (much less 9th) root or adding bass-note type extensions, I pretty much play rhythms like a six-string plus some chords where I move them to the 7th-string root or occasional eight, but that low I tend to do more melodies or double-stops. Part of that is on me because I have not learned how to fully use the guitar for extended chords, nor learned enough tapping to fully use it. But for melodies and playing things up and down the neck it has been fine.

My other main complaint, if you want to call it that, is that my six-string guitars feel weird now. I'll have to adjust, but I feel much more comfortable on my nine-string now that I do on my six-string.

So the short version (now that you've presumably read the long version) is, yes. Is it necessary? Probably not. Will I use all nine strings? So far, signs point to yes. I certainly appreciate having them all around (the ninth one mainly for putzing around open to chug on C#, but eventually for playing more purposefully). To me it is like having a Bass VI only one string lower (for range I may not use much but might, and more notes-under-finger for flexibility playing higher up the neck which I find valuable) while maintaining the high-end of a standard six-string.

Of course, your mileage may vary and all that.

-Cheers


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## scrub (Jan 11, 2016)

i hear a new 17 string Ibanez is coming out. CAN'T WAIT! GASSING! So low it's barely audible.


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## Alex Kenivel (Jan 11, 2016)

scrub said:


> i hear a new 17 string Ibanez is coming out. CAN'T WAIT! GASSING! So low it's barely audible.



Right.. after the new Axe FX Ultra update


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## Halowords (Jan 11, 2016)

scrub said:


> i hear a new 17 string Ibanez is coming out. CAN'T WAIT! GASSING! So low it's barely audible.



Well, there is the 24-string (very playable) Harpejji K24.
Marcodi Musical Products: Makers of the harpejji







Marcodi Musical Products: Makers of the harpejji | Sights & Sounds



I know it's not a guitar per se and not typical to the music this forum generally caters to, however, it is still a viable option. As are the Warr guitars and Chapman Sticks.

-Cheers


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## Drew (Jan 11, 2016)

Konfyouzd said:


> I see them being really useful for 4+ finger tapping stuff--even 10s. It'd allow you to use the same note for a chord as a note that you're using for a lead while still allowing the chord to ring out. Doing it with less strings might end in such a way that you cause one of the notes on your chording hand to stop ringing out. But for regular playing I really haven't seen anyone do anything impressive yet. I'm surprised no one has posted any videos yet.



Yeah, I've always thought that for me to get into something with more than 7 strings, it would probably be like that - predominantly clean toned playing, either touchstyle two-hand tapping stuff or fingerstyle playing with partial chords and walking bass lines. 

I kind of suck at both techniques, so I haven't yet bought an 8. It'd be fun, though, and while I don't know if it'd get used to a musically interesting extent, I think it'd be fun to have an 8 or 9 string kicking around. I just have neither infinite gear storage space, nor infinite gear buying budget, so I spent my money on gear I know I'll actually use.


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## Insomnia (Jan 11, 2016)

Interestingly enough, I tried out the Ibanez RG 9-string (less expensive model, the name escapes me) through a Mark V 25, and it sounded awesome. However, lets face it, that low C# is kind of a novelty unless your surname begins with 'A' and ends with 'basi'...


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## Bearitone (Jan 11, 2016)

Emperor Guillotine said:


> All Justin did was 0-0-0-0-0.
> 
> Mike Gianelli on the other hand shreds on his 9-string. He has videos all over Instagram, Facebook, YouTube, and EMG TV.




I don't like the active sound, but his playing is beautiful. I love when a guitarist can go all over the place while still being rhythmic and not "shreddy"

guys a beast


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## ThePIGI King (Jan 11, 2016)

Insomnia said:


> Interestingly enough, I tried out the Ibanez RG 9-string (less expensive model, the name escapes me) through a Mark V 25, and it sounded awesome. However, lets face it, that low C# is kind of a novelty unless your surname begins with 'A' and ends with 'basi'...



Dude, soooo close! Just take out the space between "RG" and "9" and you've got the model RG9! I think I could use a C# pretty decently, without being "djenty" or anything. I'm not the best composer, but I just got an 8 and I'm using that pretty well already...

Instruments are what you make of them. If you think you could use it, or would enjoy it, than go for it. The only rules and boundaries in music are the ones your mind places before you.


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## Devyn Eclipse Nav (Jan 11, 2016)

tbh my favorite 9 string player out there is Wesley Belmont - he does what he calls "hyperdjent" which is really awesome - he plays all fingerstyle, too, lots of slapping. Uses an Agile 930 with 909X pickups, and a kahler - tunes rather odd, tho, something like D1-G1-D2-G2-D3-G3-A3-D4-D3 - that highest D string is a plain string, used as a drone string, so yeah what he does could be done on an 8 string, but it's awesome


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## johnpyeatt13 (Jan 12, 2016)

Zeno said:


> tbh my favorite 9 string player out there is Wesley Belmont - he does what he calls "hyperdjent" which is really awesome - he plays all fingerstyle, too, lots of slapping. Uses an Agile 930 with 909X pickups, and a kahler - tunes rather odd, tho, something like D1-G1-D2-G2-D3-G3-A3-D4-D3 - that highest D string is a plain string, used as a drone string, so yeah what he does could be done on an 8 string, but it's awesome



I just checked him out. He's very amazing. I really like his tone.


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## ThePIGI King (Jan 12, 2016)

^^ I think he's a fellow SS.org'er. Cause I originally heard of him here.


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## ElRay (Jan 12, 2016)

They're abominations, but must be disposed of correctly. PM me and I'll give you an address to send any you have, and I'll they'll dispose of them properly.


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## blacai (Jan 12, 2016)

Is it licit if you buy one also when you don't listen to music that uses it... ?

I mean, like I've never played piano, I don't listen music with piano... but I want to learn piano.

What I would like to point is the fact the instrument should motivate you, also when you don't have idea what to do in the beginning.

9string is so different to 6-7, we could treat it like a new instrument and try to see what you find out.

-->I am bored at work, philosophical moment.


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## Halowords (Jan 12, 2016)

blacai said:


> Is it licit if you buy one also when you don't listen to music that uses it... ?
> 
> I mean, like I've never played piano, I don't listen music with piano... but I want to learn piano.



^ What he said. I don't listen to a ton of Djent or that style per se. I mean, yeah I have several Meshuggah albums and like them but that's not I got the thing for. I like Tobin Abasi and, likewise, that's he and AAL are not my go-to and not why I got a nine-string. Inspiring? Yep! But not why I got a nine-string.

It opens up options. Not JUST for tapping or Djenting (whatever that means) or chugging or playing bass-and-guitar all at once. It inspires me to play with greater complexity, allows me more tonal range, and a bit more novelty.



blacai said:


> What I would like to point is the fact the instrument should motivate you, also when you don't have idea what to do in the beginning.



That seems to really encompass a lot of these sorts of questions, at least for me. To me, having that range allows me, hell in practically invites me, to explore. Not that a six-string doesn't, and there is something to be said for mastering a six-string guitar or four-string bass or something like Ringo's, what, six-piece drum kit? But this really allows me more notes and more combinations and strangely all without being over the top. It is just a continuation of notes to me much like a piano is the same series of notes just over a spread of octaves. If having more strings/frets/notes allows you more freedom and inspiration or motivation to play or create things that have meaning or value, then great! If not, or it if becomes redundant or unnecessary and want to stick to a six, seven, or eight string, or find it more valuable to drop down to four or five strings, then great!

[/rant]

-Cheers


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## Spicypickles (Jan 15, 2016)

There no such thing as mastering an instrument, IMO. People shouldn't feel the need to justify having more strings based on their "skill" on a six string. These kind of guitars are only worth it if you want it. At any rate, you can always play 6 string stuff on a 7-8-9.


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## laxu (Jan 15, 2016)

While people have made some cool tunes with the Chapman Stick, I've yet to hear anything great come out of 9 string guitars really. They feel like a product that most manufacturers just do half-assed. Fanned frets and multi-amp outputs for the 9th, 8th and maybe even 7th string should be the norm but instead we just get the bare minimum of a wider fretboard, extra strings and pickups.

Guitar amps and cabs aren't really meant for that low notes so more often than not, especially if overdrive is used, the lowest strings sound like a fart.


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## Spicypickles (Jan 15, 2016)

But farts are cool


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## Jayesskerr (Jan 17, 2017)

Not that I'm anybody, but I picked up an RG9 while I waited on my Chapman Stick order; I totally didn't dig the 9 string... 7 is good enough for me when it comes to guitars hahaha


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## Hollowway (Jan 18, 2017)

6 ok
7 wow this is cool!
8 OH MY GOD HOW DID I EVER LIVE WITHOUT THIS
9 why does this extra string sound like ass?

That's my take on it. I own two (a 9 and a 10) and I'm determined to get it right, but it's just not another step up in the awesomeness graph.


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## Bearitone (Jan 18, 2017)

Hollowway said:


> 6 ok
> 7 wow this is cool!
> 8 OH MY GOD HOW DID I EVER LIVE WITHOUT THIS
> 9 why does this extra string sound like ass?
> ...



Have you tried a 30" scale length for the lowest string?


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## Hollowway (Jan 18, 2017)

Yeah that's all I've tried, actually. I almost feel like a shorter scale would work better, as the string wouldn't be so long. What's been your experience? Have you tried a 28"?


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## A-Branger (Jan 19, 2017)

Halowords said:


> I know it's not a guitar per se and not typical to the music this forum generally caters to, however, it is still a viable option. As are the Warr guitars and Chapman Sticks.
> 
> -Cheers




pretty cool, but by this point you better off getting a keyboard and a good sample library


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## downburst82 (Jan 19, 2017)

I picked up a schecter hellraiser 9 string a few weeks ago during boxing day sales and ive been having lots of fun on it. The low C# probably needs a heavier gauge (.100 right now) but it sounds pretty decent. Intonation will probably be tricky to get perfect but its not bad really and I haven't even messed with it yet. 

I am by no means and amazing musician or anything so im probably not taking full advantage of 9 strings properly but I hardly take advantage of 6 properly. I still love playing and being inspired by new things though and its been great for that.

So it was worth it for me (but I did get it for a crazy good price)


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## Bearitone (Jan 23, 2017)

Hollowway said:


> Yeah that's all I've tried, actually. I almost feel like a shorter scale would work better, as the string wouldn't be so long. What's been your experience? Have you tried a 28"?



Eh. I doubt a shorter scale would work especially if you're trying to improve clarity. 

To me the ideal tuning for a 30" scale guitar is drop E with a .080 or .090 gauge string on the low E. I wouldn't personally tune any lower because I hate using strings any thicker than that. They just start to get this "round" sound to them. Just my opinion though.

EDIT: And no I don't have a 28" but, I do have a 28.625" 8 string that I tune to drop F with a .080 guage for the low F. 
Feels great, sounds great.


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## Winspear (Jan 25, 2017)

kindsage said:


> Eh. I doubt a shorter scale would work especially if you're trying to improve clarity.



EDIT: To try and put my post below into less words...If you're at a scale/gauge/tension/tone combination that is just about reasonable, a significant jump in scale length can cause you to need to _increase _the gauge to compensate for the extra flexibility of the scale length. Depending on the jumps of the brands offering, and string construction, you might end up with an 85 on 29" actually having_ more _inharmonicity (muddiness) than an 80 on 28" for example. Perhaps 28.5" would have improved the tone significantly enough and increased the tension a tad without introducing too much play to the string in this case, allowing you to stick with the 80 rather than make a big jump to 85.

Original post:
It's about how much play the string has. In an ideal world it would be an illogical thought process indeed, but in reality you can come across a situation such as (all numbers/tensions random just for explanation):
-You try E with a .090 on 27". The tension is right but it's too muddy.
-You move to 29" and try E with an .080 on 29". It gives the tension you like on paper, the same as the 27" .090. It sounds clearer because it has a lot more room to vibrate, but...it has a lot more room to vibrate. The tension you liked on 27" is now not enough. You have to up the gauge to the brands next offering which may be 85 say. 
-The 85 is tight enough but bordering on too muddy again.
-You step back down, to 28" this time, with the 80 gauge again. It's looser than it was on 29". Looser even than the .090 on 27". But it hits the spot just right at being just about tight enough (because it has less room to flop about than it did on 29"), and sounding clear.
With variables such as the brands jump in gauges, and perhaps differences in construction too, you can come across situations like this often it seems. 
It's quite strange. 
An extreme example would be taking a bass scale length like 34" and setting it up to play like a guitar. If you use 25.5" with 20lbs, you're going to need way more than 20lbs on 34". Maybe even about 32lbs for a similar feel, leading to quite a monster string (which in turn requires heavier tension as it has more mass to cause noisy vibration). Backing down to a reasonable 30" will allow dropping of string tension significantly, leading to more of a gauge reduction than you might expect. 
This is all kinda theoretical and based on fairly limited experience, but I've experienced and read a few similar counts of it now. It's incredibly hard to guess exactly how things are going to behave and whats going to be better in practice. If we were playing only open strings with high action then yes longer is _always _better, but with action and fret buzz coming into play, it does complicate things to less linear relationships


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