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  1. Replies
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    Good point.

    Good point.
  2. Replies
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    The MV is wired as floating variable resistor...

    The MV is wired as floating variable resistor connecting between (ideally) equal amplitude, opposite phase voltages. So signal voltage across the MV resistance corresponds to twice the value at each...
  3. Copper and aluminum are much better conductors...

    Copper and aluminum are much better conductors than steel. When considering aluminum, don't forget that you need a closed/shorted loop with a very low resistance contact between the ends. This is...
  4. Would you mind to post your schematic? Up to now...

    Would you mind to post your schematic? Up to now we only have a modified '65 TR RI schem.
  5. Other than with standard PUs there is no benefit...

    Other than with standard PUs there is no benefit from using more than one turn for the shorted primary (sensing loop) of the "transformer PU". Rather it is important to keep the resistance of the...
  6. Sorry, these equations are simply wrong. Output...

    Sorry, these equations are simply wrong. Output cannot be read from coil resistance. Especially single primary loop transformer PUs like the Alumitone need a heavy gauge/very low resistance primary...
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    A speaker impedance has (at least) two zero phase...

    A speaker impedance has (at least) two zero phase frequencies. The lower one(s) at the bass resonance(s) and the next typically around 400Hz for a guitar speaker.
    According to Wikipedia some...
  8. Driving the tank from a power amp seems kind of...

    Driving the tank from a power amp seems kind of venturous without a dummy load and suitable voltage divider. I don't think the transducer can take more that 1..2W.
    OTOH, an equalizer might not be...
  9. BTW, screen resistors can also reduce the risk of...

    BTW, screen resistors can also reduce the risk of oscillation.
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    AFAIK, nominal speaker impedance is...

    AFAIK, nominal speaker impedance is measured/defined at 400Hz. It often stays within around 20% between 200Hz and 1kHz and rises below and above. A 4x12 Marshall cab has an impedance of around 40...
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    The standard method requires: - a load...

    The standard method requires:

    - a load resistor corresponding to nominal output impedance
    - a continuous sine input signal of around 100mV and 400Hz
    - an AC voltmeter (preferably true RMS),...
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    Wondering about the anti-parallel 470 E-caps in...

    Wondering about the anti-parallel 470 E-caps in the Deep Blue. Doesn't seem to make sense. For a non-polarized cap they would need to be in anti-series (requiring 4 times the capacitance per cap).
  13. While there may be a tendency, I don't think...

    While there may be a tendency, I don't think there is a general answer to this question as too many variables are involved and its a dynamic problem.

    You may find some useful info about...
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    The series resistor means no extra load for the...

    The series resistor means no extra load for the winding. The winding just feels the (3A) current and has to supply ~19W (its terminal voltage times current). Just make sure it is rated for 3A. The...
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    Sure, that's the way Gibson "relieved" the weight...

    Sure, that's the way Gibson "relieved" the weight of Les Pauls since the early 90s.
    But I just place my wah on the floor and don't care about weight.
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    Who else could tell you if you like a buffer...

    Who else could tell you if you like a buffer after the wah?
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    But why? Any wah can be easily wired for true...

    But why? Any wah can be easily wired for true bypass.

    BTW, original Vox wahs were considerably lighter as the housing was cast aluminum not heavy zinc as most reproductions.
  18. No, not the same at all.

    No, not the same at all.
  19. This doesn't point to V4b as being the (sole)...

    This doesn't point to V4b as being the (sole) source of oscillation, especially if the amplitude of oscillation is greater before R32 than after. Oscillation often/mostly involves more than one...
  20. What happens if you just unlink V1b and V2b...

    What happens if you just unlink V1b and V2b plates, everything else original?
    What happens if you disconnect C17, everything else original.
    Can you see oscillation at the plate of V2b (pin 6).

    ...
  21. This makes the HF oscillation frequency something...

    This makes the HF oscillation frequency something like 60kHz (I count ca. 6 positive HF peaks per division, one full division corresponds to f=1/0.1ms=10kHz). Referring to pictures 2,3,4. Pic1 must...
  22. What changes if you lift one end of C13? Or lift...

    What changes if you lift one end of C13? Or lift one end of R30 (1M)?
  23. Oh, I see. Thanks. One more remark: Some...

    Oh, I see. Thanks.

    One more remark: Some speakers like the ones in the photo have their minus terminal riveted to the speaker chassis. This allows only one of speaker chassis to be grounded in a...
  24. Yes, the speakers appear to be wired in parallel...

    Yes, the speakers appear to be wired in parallel - but out-of-phase.

    I thought they should be wired in series for 8 Ohm with the new OT (post #1)?
  25. In most tube amps one side of the OT secondary is...

    In most tube amps one side of the OT secondary is connected to the amp ground/chassis. (This way also one end of the speakers voice coil is grounded.)
    While this is mandatory for amps with global...
  26. I think I got it. But it's such a shame that a US...

    I think I got it. But it's such a shame that a US (Illinois) based company with a long tradition got that bad a reputation.
  27. Doesn't matter, headquarters are responsible for...

    Doesn't matter, headquarters are responsible for product quality from all production sites. I know that you can get identical quality out of anywhere if you care, invest and check. Quality management...
  28. Sorry, I did not mean to say that OT primary DCR...

    Sorry, I did not mean to say that OT primary DCR influences idle current. It does not.
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