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Posts posted by psarkissian

  1. Regarding sending a piezo wire to another string doesn't mean anything.

    Each string has it's own signal line. The processor will treat the E-string as

    if it were the A-string, so of that signal path won't sound right. The processor

    knows which string is which, it expects to have the correct string on the

    correct signal path line.


    If the bridge and its piezos are replaced and it didn't solve the problem,

    then the problem is not the bridge and its piezos.


    If the electronics were replaced and it didn't solve the problem, then the

    problem is not the electronics.


    Process of elimination. That narrows it down to something mechanical.

  2. The FFT displays are nice, but nothing to show me how your test is set-up.

    As you have pointed out,... not 100% objective.


    The You Tube is a good start, but I can't see what or how you are doing what

    you are doing.


    The piezo FFT indicates transients the you have labeled. That would point to

    something with the piezo and/or something before the piezo. The only thing before

    the piezo is mechanical. Therefore, not DSP or output, or electronic,... therefore, not

    the Firmware.


    Firmware models the guitar it is meant to model. Modeling is a template, a mask thru which

    the signal passes thru.


    There is a ring in the You Tube audio. I sound like that when I flat-pick. Part of the

    reason I finger-pick (which is most of the time).


    As you pointed out, this occurs even when,... not connected. The mechanical is the

    source, the electronics are the processor/amplifier.


    Make use of an equaliser to band-reject the frequency set you find objectionable.

    It's about sculpting that sound.



  3. "If it were an issue with the firmware then every single Variax running the same firmware would have the same problem but it seems that most people don't have this problem but many do"--- that is correct.


    As far as Firmware goes,... "Spank", the Fender Strat sound,... sounds the way it does, because that's the way

    the guitar that was modeled sounds.


    Some of the test points shown that used for the FFT displays would not be good examples to use. 

  4. Feeding noise through a decoupling capacitor creates a filter with the

    surrounding components (that may act as resistive elements). This weighting

    filter will skew the noise results in a way that will emphasize some frequencies

    and de-emphasize others, in a way that will not be an accurate representation

    of the noise injected in the circuit. A filter will spread or "smear" the frequencies,

    giving erroneous peaks and troughs in the FFT results.


    Injecting noise into the DSP means nothing. DSP doesn't process noise, it processes

    digital bits.


    Tampering with the circuitry that way is not a good idea, and even worse without

    a schematic,... and may even void any warranties.

  5. Use the equaliser on the HD500 to bring down the desired frequency.


    Select a different impedance on the HD500. Some impedances in  the

    selections are noisier than others, some players like that, it gives grit

    to the sound that some like. Some impedances selected have a lower

    noise floor.


    If the string is vibrating radially and not transversely, then the pick-up is

    set to close to the strings. By the way, speaking of strings what is the

    string gauge set being used?


    "Spank" is modeled from a 1959 Fender Stratocaster. The low-E string

    has a characteristic bite to the sound that the Delta Blues and Gulf Coast

    Blues players value.


    Presets are a starting point,... sculpting a sound only starts there.


    There is not an error in the firmware because that's what the guitar sounds like,

    that the sound was modeled from.


    It's like bringing up a model of a Marshall tube amp and wanting it to have the

    tube sound of a Marshall, but without the noise floor and hum that goes with it.

    That defeats the whole purpose of the model,... that is, to sound like the item

    being modeled from.



    "Spank",.... It sounds the way it does, because that is what the guitar it's modeled from

    sounds like. That's what modeling is.

  6. No super glue,... use white glue like Elmer's. It's what we use here.
    If you use super glue and it's not aligned right, you'll be screwed.

    stevekc is good enough to get away with using super glue,... he's
    one of four or five people in the Americas (besides myself and a
    couple others here at Line 6), that I trust to do a mod on a JTV
    without making a mistake.

    If you haven't done this before use Elmer's or as Steve said, a Luthier,
    ... or guitar tech.

    Those are supposed to be lightly glued in at the factory. Some how it
    didn't hold. Sorry about that.



    Oh,... and it's not graphite, it's some mix of something different, it is

    made by Graphtech.

  7. Potential? No, at some point it will become a problem. It's an

    output load thing to the amp circuit on the JTV main board. Both

    JTV outputs are not designed to be used at the same time.


    As for the other thing, since you can engage either Model or mags,..

    ... one or the other at a time, I'm not sure I see what the benefit is.


    When magnetics are turned-on the Models are turned-off, and

    vice versa. Not sure what you're trying to do there. Preset the

    levels maybe?

  8. No mags to Model blend,... it would never work with the Alt Tune.

    Models would be Alt Tuned while the mags wouldn't be. That would

    sound really bad.


    Using VDI out and 1/4" out simultaneously would create problems

    of circuit loading and current draw issues (with or without battery).

    The circuit board wouldn't handle that kind of load. In case anyone

    was thinking about that one.

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