Boss Poly Shift XS-1 and XS-100 Official Thread™ With Video(s)

[Sascha Franck]

In the world of real time pitch shifting that 13.6ms figure is state of the art i believe.

Might be. But then, where's those slightly more complexed pristine clean faux pedal steel chords? That's a thing I'd really like to do with such a thing. Apparently it's still not good enough for that kinda thing.
And fwiw, what I'm really wondering about is how Boss manages to keep latencies so low on their SY units (even when feeding them with a stock pickup signal), just to completely crap out once it's about pitch shifting.

 

[JiveTurkey]

With a unit such as this, the main purpose is to use 100% wet signals, though. At least that'd be it for me.

With the 3-5ms RTL of my main rigs, this would push me almost to 20ms. No thanks. Could get away with it for the odd special FX thing, but playing an entire song through that would make me cringe.

Im using it with an amp/pedalboard rig; not another modeler. But absolutely agree on that figure being far too large if that were the case.

 

[Sascha Franck]

Im using it with an amp/pedalboard rig; not another modeler.

Fwiw, I'm getting the same kinda latency figures from my modeling rig compared to a traditional rig by kinda "compensating" via the distance of the monitoring source. I'd very likely place any real amp/cab at least a meter or so further away from where I'm standing than where I place my FR wedge.
Anyhow, regardless of the exisating rig, 13+ ms on top are too much, even for live situations.

 

[Chocol8]

just to completely crap out once it's about pitch shifting.

How do you shift a pitch without reading in enough of the original signal to know what the pitch is? For the low E on a standard tuned guitar, a single full cycle of the fundamental will take 12.5 ms. I am not sure if they need to see a full cycle, but there has to be a limit between the lowest input frequency the pedal can work with and the lowest possible latency.

 

[Sascha Franck]

How do you shift a pitch without reading in enough of the original signal to know what the pitch is? For the low E on a standard tuned guitar, a single full cycle of the fundamental will take 12.5 ms.

This is not how things work (at least not for any "simple", non-diatonic pitch shifting).
First off: By that token, when you strike your low E string, it'd take at least 12.5ms for any impact to reach your ear (plus the time it takes to be sent through whatever devices and the air). And we all know that this isn't the case. Yes, your ear will only be able to faithfully recognize the fundamental of the note after that amount of time, but that's not the only thing to exist in a guitar string's tone. The attack (which you may or may not call a "pitch-less" impact) is almost instant. And that's what defines the timing of a note, not it's decay's fundamental pitch.

Static pitch shifters don't do any analyis, they just multiply or divide the values of any incoming signal by a given amount. The best example possibly being older octavers, working with very little latencies. They just don't care about the note pitch but divide anything by 2 (or 4, in case there's a 2nd octave down option).

I am not sure if they need to see a full cycle, but there has to be a limit between the lowest input frequency the pedal can work with and the lowest possible latency.

No. See above. The incoming pitch is completely irrelevant for any non-diatonic (or otherwise analysing) pitch shifting.

 

[metropolis_4]

Might be. But then, where's those slightly more complexed pristine clean faux pedal steel chords? That's a thing I'd really like to do with such a thing. Apparently it's still not good enough for that kinda thing.
And fwiw, what I'm really wondering about is how Boss manages to keep latencies so low on their SY units (even when feeding them with a stock pickup signal), just to completely crap out once it's about pitch shifting.

The general rules of pitch shifting have always been:

1. The more complex/dissonant the harmony the more it struggles.
2. The cleaner the tone, the more you’ll hear the artifacts.

Remember when the Quad Cortex came out and people swore the pitch shifter was polyphonic because it sounded fine when they were playing root/5th power chords with heavy distortion?

 

[Sascha Franck]

The cleaner the tone, the more you’ll hear the artifacts.

Yeah. This had me irritated way back already. I always thought distortion would bring out "harmonic issues" (I know, it's not a proper term by any means...) more than clean sounds, but the opposite is the case, it pretty much masks some of those issues.
But it doesn't stop there - some pitch shifters actually seem to work better post distortion. Which I find to be pretty weird as distorted sounds are pretty much harmonically complexed. Also, if you really wanted to emulate a detuned guitar, that obviously would have to happen straight after the guitar's output.

Anyhow, given how far we have taken technology already, it's quite weird that there's still no proper pitch shifting working well with polyphonic material *and* low latency.

Remember when the Quad Cortex came out and people swore the pitch shifter was polyphonic because it sounded fine when they were playing root/5th power chords with heavy distortion?

Fwiw, while defenitely nitpicking, pretty much any pitch shifter is polyphonic as in that you can feed all of them polyphonic material. Just that the output of some will sound worse than others.

 

[metropolis_4]

Yeah. This had me irritated way back already. I always thought distortion would bring out "harmonic issues" (I know, it's not a proper term by any means...) more than clean sounds, but the opposite is the case, it pretty much masks some of those issues.
But it doesn't stop there - some pitch shifters actually seem to work better post distortion. Which I find to be pretty weird as distorted sounds are pretty much harmonically complexed. Also, if you really wanted to emulate a detuned guitar, that obviously would have to happen straight after the guitar's output.

Anyhow, given how far we have taken technology already, it's quite weird that there's still no proper pitch shifting working well with polyphonic material *and* low latency.



Fwiw, while defenitely nitpicking, pretty much any pitch shifter is polyphonic as in that you can feed all of them polyphonic material. Just that the output of some will sound worse than others.

I don’t know the technical details, but whenever guitarists talk about polyphonic vs monophonic in regard to pitch shifters it’s generally understood that what we’re referring to is the ability to track and reproduce more than one pitch at a time. Play an interval on an old monophonic Whammy and the output oscillates between the two pitches. Play the same interval on a newer polyphonic Whammy and you hear each note shifted.

There are some cool creative uses of that warble of older monophonic devices. Listen to My Iron Lung by Radiohead for example

 

[Sascha Franck]

I don’t know the technical details, but whenever guitarists talk about polyphonic vs monophonic in regard to pitch shifters it’s generally understood that what we’re referring to is the ability to track and reproduce more than one pitch at a time.

I'm quite aware of that definition, but there's a lot of grey area. I have an old Whammy II and it works kinda ok-ishly on certain chords (I kinda like using it in -2 mode and then "pre-bend" down, works nicely for a faux pedal steel thing), even if its not designated to work polyphonically. And then there's some polyphonic shifters warbling like mad.

 

[BROCKSTAR]

MSS user over on fractal said this

"I bought one this weekend and I am super impressed with it. I sold my drop tune years ago in favor of the Axe virtual capo. My needs generally don’t require a drop more than 2 semitones.

When I compare the xs-1 to the Axe virtual capo dropping c to a#, they are remarkably close. Having said that, out of the box the xs-1 sounds better. Changing virtual capo tracking to 6.5 and adding an eq after (dropping some 1k and boosting some 8k) gets them super close. They both track well and have, to my ears, similar but slight artifacting. I figured I would be sending the xs-1 back but I am keeping it. I think it sounds a little more natural than the virtual capo. Both are great IMO."

Boss XS-1 Poly Shifter

Bought one of these before I finished my first cup of coffee this morning. I've been a long time Digitech Drop user and super curious how this compares! It's got a couple neat tricks and can pull off a convincing chorus. I'll leave some more thoughts when it arrives next week...

forum.fractalaudio.com

 

[Chocol8]

This is not how things work (at least not for any "simple", non-diatonic pitch shifting).

I can see how you could do a simple shift down, but I think to do more complex shifting in both directions, the pedal has to have some ability to "look ahead" which means latency. Does anyone have a low latency polyphonic pitch shifter? Why not?

 

[JiveTurkey]

I hate ordering from anywhere other than Amazon at this point I've got wrestling metal riffs to learn

 

[Chocol8]

I hate ordering from anywhere other than Amazon at this point I've got wrestling metal riffs to learn

Long and McQuaalude doesn’t do same day home delivery yet?

 

[JiveTurkey]

Long and McQuaalude doesn’t do same day home delivery yet?

It'd be a long drive to my house if they did

 

[Whizzinby]

I hate ordering from anywhere other than Amazon at this point I've got wrestling metal riffs to learn

Dude I hear you on this. I hate the idea of using Amazon over a dedicated music company, but next-day and two-day shipping is hard to resist. Ain’t nobody got time for 5-6 day shipping unless you’re the only game in town for an item.

 

[JiveTurkey]

Dude I hear you on this. I hate the idea of using Amazon over a dedicated music company, but next-day and two-day shipping is hard to resist. Ain’t nobody got time for 5-6 day shipping unless you’re the only game in town for an item.

Amazon.com : 7 string guitar

 

[JiveTurkey]

If I played cleans; this is pretty impressive!

 

[JiveTurkey]

Arriving today. Got my testing plan all red to go.

Going to test the warble/garble and latency factors with my standard tuned guitar on the following in front of my amps:
-1=Eb
-3=C# Standard
-5=B Standard
-7=A Standard

Bonus points for the chorus/detune mode.

This will also determine my "oh look I bought an unnecessary guitar in that magic October spot right before Christmas spending really fires up and a $1k+ piece of gear might raise some eyebrows!" approach

 

[AlbertA]

Arriving today. Got my testing plan all red to go.

Going to test the warble/garble and latency factors with my standard tuned guitar on the following in front of my amps:
-1=Eb
-3=C# Standard
-5=B Standard
-7=A Standard

Bonus points for the chorus/detune mode.

This will also determine my "oh look I bought an unnecessary guitar in that magic October spot right before Christmas spending really fires up and a $1k+ piece of gear might raise some eyebrows!" approach

Play some complex sustaining chords - let's see how much warble this thing has :)

 

[JiveTurkey]

Obligatory I need to eat supper reaction. I assume you wouldn't expect anything less from me.


1. Pedal feels super solid. Could have been an extension of the SY1000 chassis. Good.

2. Down a single halfstep is good. Whole step is good. Even down 3 is good. Beyond that; it is completely a victim of Boss pitch shifting where there is this weird thing with the low E. It's like a cocked wah stuck in a low "wow" setting. I haven't played a tuned down guitar in forever so maybe I am wrong and this is an experience with a physically downtuned guitar as well but I don't think so. Latency seems to be noticable around 5 down. Doable; but noticable. Weird low end is also exacerbated by different drives. SD-1 was TERRIBLE with it. GT-OD was there but not as bad. MXR Micro Amp 2 was probably best sounding with it?

3. Detune mode is not audible. Unless I am so used to hearing either the MXR stereo chorus or the FAS stuff where it's lush AF? I don't think so. I might be missing something in the menu system they've included.

4. Whammy is kind of neat? I would probably never use it in retrospect. I bought it mainly for presets with the whammy being a sort of add-on item.

5. Up 2 semitones is solid. It definitely has a "fake" sheen to it but with a bass in a mix; it would be fine for that (AKA tune baritone or 7 up to C# for LB riffs)

6. I think I am probably the worst "new to me piece of gear" person I have ever met If I had to rate it now; I would buy the single stomp and organize songs and change tunings on the fly per group vs. this piece.

I can see using this with my 6 string and whatever 7 or baritone for the wrestling metal stuff. I would absolutely not use it to go down or up for anything more than 3.