Pizz/Arco "Blend" pot mod on NS NXTa - anyone tried one?

Discussion in 'Electric Upright Basses (EUB's) [DB]' started by kumimajava, Jun 12, 2020.

  1. kumimajava

    kumimajava Supporting Member

    May 19, 2010
    Tokyo, Japan
    I have had the NXTa-5 for a while, and don't really miss the mags from a CR5, nor the extra EQ (done further down the signal chain), but thought it might be interesting to see if the Arco & Pizz signals could be blended. I'm thinking - I must not be the first person to think of this?

    Would a simple "passive blend" pot (like used on 2-pickup basses) work - with an appropriately adjsuted "resistance" on the pot (and what might that resistance be)?

    I've looked all over TB, and found a thread with some mods on an (old - pre 2016) WAV series, but that didn't include blending.

    So - if you've had the same thougth, and/or experimented with a simple blend-pot on an NXTa, I'd love to hear about your experience!

    Thank you for your time :)
  2. Jared Houseman

    Jared Houseman

    Jul 5, 2018
    I'm not certain but I saw somewhere that both pickups are always on and the pizz/Arco switch swaps the phase of one of the pickups. It's not actually swapping between the elements.

    I suppose it would be possible to "blend" between the two modes but it would need digital processing
    kumimajava likes this.
  3. kumimajava

    kumimajava Supporting Member

    May 19, 2010
    Tokyo, Japan
    Thanks for pitching in - that's really interesting. That might shed some light on why I saw something rather weird (in terms of how the pizz/arco switch is wired) when i peeded into the control cavity, just after posting this thread. I'm attaching a few (rather poor - phone-cam) pics in case anyone's curious what the simple electronics of an NXTa look like :)

    Not sure what the resistors are doing in there- i couldn't see the values (they're facing downwads), but it looks like the red & black leads are going into the leftmost 2 lugs on the switch, blue goes in "upper middle" and green goes to "lower right" - then some cross-over leads & resistors in there somewhere. there's a lot going on in that small tight space, so I'm not sure I identified everything correctly.

    20200613_091142.jpg 20200613_090854_HDR.jpg 20200613_091001_HDR.jpg
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  4. Mudfuzz


    Apr 3, 2004
    Depending on the year crs have a 3 way switch or a knob (does it blend? I have a older one with a 3 way switch) for a inbetween setting... I dont know why the nxt and wave dont maby there is something in the pre that does something...
  5. Wasnex


    Dec 25, 2011
    The Polar pickups on the passive instruments involve two pairs of piezos and a toggle switch so you can select which pair of piezos is in the circuit. One pair is oriented horizontally and one pair is oriented vertically. Blending the two pairs of pickups may not work very well with the passive basses, as the four piezos may load each other down to much.

    I use to play one of the original US series basses that had magnetic and piezo pickups. I did not care for the piezo soloed and I also did not care for the way the instrument sounded bowed. So I tended to blend the magnetic pickup with one of the piezos. The US series had a switch to toggle to select between vertical and horizontal piezos.

    The current EU series is supposed to be made to the same spec as the old US series. However per the manual, the toggle for the piezos has been replaced with a piezo blend. There is also a blend knob for magnetic versus piezo.
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  6. Matthijs

    Matthijs Supporting Member

    Jul 3, 2006
    The wiring looks exactly the same as in the older wav. The difference between the settings is the fase is reversed on the treble side piezo and a cap is added.

    blending is not possible, but you can add a pot to control the treble side. This way you can add a usefull bass-side only sound and blend in the standard arco or pizzicato sound.
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  7. kumimajava

    kumimajava Supporting Member

    May 19, 2010
    Tokyo, Japan
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