Strange harmonic at Double Verb amp

Piing

Piing

Axe-Master
I said at the Q7 Public Beta thread that I hear a weird harmonic when using the Double Verb Vib, but I've gone back to Q6.03.1 and it is still there, so I'll start a new topic.

Resetting the amp doesn't help.
Effect is reduced when using Double Verb Nrm or SF
No problem at all when using other amps like 6G4 Super or 59BAssguy or Jazz 120 (haven't tried them all)

Here is a recording

And here is the patch
https://dl.dropboxusercontent.com/u/46804116/Double Verb Weird.syx

Any ideas?

ps: Axe-FX II Original
 
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Yah, it almost sounds like action set too low...but I guess it's not that - since other amps are fine.
 
WTF? Now I am listening the clip at the office (with IEM’s) and I cannot hear the harmonic!! :eek:

At home I was monitoring with both speakers and headphones, using the Axe-FX as USB-soundcard. (headphones connected to the Axe-FX Headphones output; monitors through a Motu Ultralite Mk3 connected to the Axe-FX stereo analog output)

So, it is not recorded to the DAW through the USB, but it can be heard when monitoring through the Axe-FX, both playing live signal or the recorded signal.

I think that the first thing I’ll have to do when arrive home in the evening is a full factory reset. o_O

ps: or perhaps my IEM's are too cheap. Can anyone else hear it? It was not buzz due to fretting, it was like an harmonizer
 
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Piing said:
WTF?

Now I am listening the clip at the office (with IEM’s) and I cannot hear the harmonic!! :eek:
Click to expand...

I'd record in the DAW and look at an analyzer waveform to see if it is in the Axe output or produced by your speakers, room, headphones or other.
 
I am playing with more than one guitar, and if it were a problem from the guitars it will not disappear when I switch to another amp model.

To avoid speculation about the guitar, now I am using the signal generator from Room EQ Wizard.

This is how it sounds when passing through the Double Verb Vib:
https://dl.dropboxusercontent.com/u/46804116/Axe-FX Weird Harmonic.mp3

And the same signal with the Amp Block Bypassed:

A System Reset doesn’t help :(
 
Similar problem with the Supreme & 59Bassguy

No problem with the BritASF100, BritBrown, DeluxeVerbVib, 6G4 Super, Citrus Terrier

No time to try them all. I'm going back to play guitar
 
Wolfenstein98k said:
Where'd he say this?
Click to expand...
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Thanks! I just got off the phone with Matt and he talked me through some of that. PI Bias Shift may as well be called "magic." Great update, Cliff! Very excited to keep diving into this one.
I went back and looked at the Liverpool model and I realized one of the PI Bias Shift values is wrong. I stupidly copied the values from the Express forgetting that the Liverpool uses a Vox-style phase inverter. I'm going back over all the models in detail before the final release so things will change.

Jan 11, 2017Report
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Ghost notes? You get something similar on a few of the NMV amps, like most of the Plexi models, when the input drive is high. It has something to do with power supply filtering in certain amps and is normal. This doesn't sound exactly like what I hear on the Plexi, but it's in the ballpark.
 
marshall2553 said:
Ghost notes? You get something similar on a few of the NMV amps, like most of the Plexi models, when the input drive is high. It has something to do with power supply filtering in certain amps and is normal. This doesn't sound exactly like what I hear on the Plexi, but it's in the ballpark.
Click to expand...
BTW, I just tested this by switching the power supply type to DC and the "undertone" or ghost note disappears. I'm pretty sure this is normal, though I suppose there could be an error in the model that is causing it to ghost more than it should.
 
Sounds like a ghost note. This is caused by supply ripple intermodulating with the note played. Many non-MV amps do this. You can reduce it by increasing the B+ time constant, reducing supply sag or changing the supply type to DC.

IMO a little "note ghosting" is cool. Adds character. My 100W Plexi ghosts like crazy but I like it. It's a trade-off. Lower B+ time constants make the amp more bouncy but increase the ghosting.
 
FractalAudio said:
Sounds like a ghost note. This is caused by supply ripple intermodulating with the note played. Many non-MV amps do this. You can reduce it by increasing the B+ time constant, reducing supply sag or changing the supply type to DC.

IMO a little "note ghosting" is cool. Adds character. My 100W Plexi ghosts like crazy but I like it. It's a trade-off. Lower B+ time constants make the amp more bouncy but increase the ghosting.
Click to expand...

Thank you for the information! I will tweak the B+ this evening.

In my case it is creating an undesired effect. I discovered this while I was using the Double Verb with a clean tone for playing the lead at the intro of Pink Floyd’s Echoes. That is a very delicate tone, and the harmonic is annoying. Perhaps it sounds good when playing fast & dirty, but not pleasant for long sustained clean notes.

Or maybe an amp with ghost notes is not the appropriate one for playing that, even with real amps.
 
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