Helix 3.01 Poly Capo Dissonance

[matsonf]

Anytime I use Poly Capo, I'm hearing dissonance in the tone, where the original pitch in addition to the Poly Capo pitch comes through, e.g., +1 (to raise pitch by a half step). Secondly, and possibly related, the tone gets more corrupt sounding the farther from 0, whether plus or minus. Is anyone else experiencing this? Version 3.01 was to fix potential audio corruption, but maybe those were different issues. 

[zappazapper]

A pitch shifter will inherently create more artifacts the further from unison it goes. Perfect, artifact-free pitch shifting does not exist, even in the monophonic realm. 

[HonestOpinion]

1 hour ago, matsonf said:

Anytime I use Poly Capo, I'm hearing dissonance in the tone, where the original pitch in addition to the Poly Capo pitch comes through, e.g., +1 (to raise pitch by a half step). Secondly, and possibly related, the tone gets more corrupt sounding the farther from 0, whether plus or minus. Is anyone else experiencing this? Version 3.01 was to fix potential audio corruption, but maybe those were different issues. 

 

Just wanted to mention that often with pitch shifting or harmony blocks people hear the actual sound coming off of their guitar strings in addition to the generated sound from their device output. This can lead to you hearing out of pitch sounds that your  audience or recording won't. Other than that, next stop, "poly auto-tune" block being added to correct Poly Capo pitch drift(just kidding) :-)

[cruisinon2]

If you're playing at low volumes, then you are also hearing the guitar acoustically... it's impossible not to. The strings are inches from your head. Record something with the pitch shift and listen to the playback... if the dissonance is gone, then that's what's happening. Electric guitars ring out acoustically much louder than you think... and when the pitch that's coming out of your speakers is not the same ad what's coming directly off of the guitar, dissonance is inevitable. 

[DunedinDragon]

I would suggest you might want to play with the tracking  and auto eq parameters on the Poly Capo and make it less rigid as I've found that can produce such artifacts depending on the tone being produced in the signal chain, the amount of change as well as the placement of where the Poly Capo sits in the signal chain.

 

[amsdenj]

You might also consider a Variax if pitch shifting is something you want to do a lot. Variax has a separate pickup for each string, so the pitch shift algorithm doesn’t have to detect the individual notes from the played chord. 

 

Also limit the effects you have going into the poly capo. The less complex the tone the easier it is for the algorithm to detect the individual notes. Keep the input into poly effects close to the dry guitar and put the effects after the poly block.

 

 

[matsonf]

On 3/16/2021 at 6:26 PM, amsdenj said:

You might also consider a Variax if pitch shifting is something you want to do a lot. Variax has a separate pickup for each string, so the pitch shift algorithm doesn’t have to detect the individual notes from the played chord. 

 

Also limit the effects you have going into the poly capo. The less complex the tone the easier it is for the algorithm to detect the individual notes. Keep the input into poly effects close to the dry guitar and put the effects after the poly block.

 

 

Thanks amsdenj - the latter suggestion turned out to be the key factor. I switched things around quite a bit to put the poly capo up front on Path A with all other effects moved down to Path B. I then put a split on Path A to route everything into Path B. That took care of the dissonance.

[matsonf]

On 3/16/2021 at 6:01 PM, DunedinDragon said:

I would suggest you might want to play with the tracking  and auto eq parameters on the Poly Capo and make it less rigid as I've found that can produce such artifacts depending on the tone being produced in the signal chain, the amount of change as well as the placement of where the Poly Capo sits in the signal chain.

 

Thanks DunedinDragon - as you suggested, placement in the signal chain turned out to be the main culprit. After making changes, the experience is definitely better. 

[matsonf]

On 3/16/2021 at 3:36 PM, zappazapper said:

A pitch shifter will inherently create more artifacts the further from unison it goes. Perfect, artifact-free pitch shifting does not exist, even in the monophonic realm. 

Thanks zappazapper - that is true. Fortunately, basic re-ordering of effects seems to have resolved the biggest part of the problem.

[matsonf]

On 3/16/2021 at 4:01 PM, HonestOpinion said:

 

Just wanted to mention that often with pitch shifting or harmony blocks people hear the actual sound coming off of their guitar strings in addition to the generated sound from their device output. This can lead to you hearing out of pitch sounds that your  audience or recording won't. Other than that, next stop, "poly auto-tune" block being added to correct Poly Capo pitch drift(just kidding) :-)

Thanks HonestOpinion - I did question at first whether I was hearing my guitar directly. Once I put on headphones, I was still hearing it come through the signal. Positioning of the effect had the biggest improvement.

[matsonf]

On 3/16/2021 at 4:07 PM, cruisinon2 said:

If you're playing at low volumes, then you are also hearing the guitar acoustically... it's impossible not to. The strings are inches from your head. Record something with the pitch shift and listen to the playback... if the dissonance is gone, then that's what's happening. Electric guitars ring out acoustically much louder than you think... and when the pitch that's coming out of your speakers is not the same ad what's coming directly off of the guitar, dissonance is inevitable. 

Thanks cruisinon2 - agreed, and that was something I verified using good headphones to make sure it wasn't in fact the guitar.

[cruisinon2]

22 hours ago, matsonf said:

Thanks cruisinon2 - agreed, and that was something I verified using good headphones to make sure it wasn't in fact the guitar.

 

Headphones aren't a magic bullet either... if they're open back cans, you'll still hear the guitar acoustically unless you're cranked up to a decent volume. Happens to me all the time with my AKG 701's.