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  1. The 1M/100nF combo has a 100msec time constant...

    The 1M/100nF combo has a 100msec time constant which means that after it shorts the gate (LED in your case) to ground it should release shortly after that.
    With disconnected SSR measure the voltage...
  2. Firstable lease check if everything is connected...

    Firstable lease check if everything is connected properly. Stays muted for how long? Longer time constant?
    Disconnect SSR from the triac and check manually if the if it's working properly...
  3. $0.05 is very low for anything. I checked...

    $0.05 is very low for anything.

    I checked Farnell's prices and they look kind of same as Mouser's:
    ...
  4. Yes, you can use it. Connect SSR's LED cathode...

    Yes, you can use it. Connect SSR's LED cathode where JFET gate is connected. Run a 1k5-2k2 resistor from SSR's LED anode to 12V supply and then connect the switching part in parallel with the sound...
  5. It's more like 3x to 4x which is not much at all....

    It's more like 3x to 4x which is not much at all. Here are some high voltage DIP4 SSR prices compared to a typical J175 mute JFET.
    ...
  6. A 300-600V DIP4 SSR will do the job. It has a DCR...

    A 300-600V DIP4 SSR will do the job. It has a DCR of ~50 Ohms when on which is the same like J175. You can also put some back to back zeners for extra insurance.
  7. Yes, I did, but at higher volumes they would...

    Yes, I did, but at higher volumes they would "sing" anyway :)
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    First supply is from Mesa and they usually using...

    First supply is from Mesa and they usually using it for relays, switching and other things.
    Depending on the design grounding at the bridge negative rail only (no CT) will provide hum free...
  9. I got my inductors from the local transformer...

    I got my inductors from the local transformer shop. Here's some observations.
    The lamination core inductor measured ~9.5mH out of the enclosure (1.2mm black steel) and ~11mH when installed. There...
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    Looking at the date of my last post it turns out...

    Looking at the date of my last post it turns out that those JJ EL34 II lasted less than a year after a very moderate use. One of them became very microphonic and developed erratic behavior...
  11. The price is simply ...inconceivable. If you...

    The price is simply ...inconceivable. If you consider that it contains shipping from China, tiny profit for the manufacturer, tariffs, taxes, dealers' fees, state tax, tiny profit for Walmart etc...
  12. I like to insure myself so in the reactive loads...

    I like to insure myself so in the reactive loads I've built so far I was using 1,2-1,3mm thick copper wire (~16AWG) air core inductors. Same for the low freq inductor. For caps my choice was two...
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    This whole thing is close to that tale about the...

    This whole thing is close to that tale about the frog that lived on the bottom of a dry well and refused to believe there's a world outside of it.

    The guy doesn't know that other than clean or...
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    Always did 12VDC regulated heater supplies in...

    Always did 12VDC regulated heater supplies in high gain amps. First two tubes are enough but sometimes I feed all preamp tnbes from the regulated supply. To avoid CF failure you can elevate them as...
  15. This is a video of a 50W toroidal OT going into...

    This is a video of a 50W toroidal OT going into saturation in real time. Frequency swept and amplitude are shown in the window below (link will expire in 30 days).

    https://ufile.io/yv6ab20v
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    After I fried my Hantek 6022BE I got an OWON...

    After I fried my Hantek 6022BE I got an OWON VDS1022l (USB isolated) for around $76 from a sale on Ali. Plenty enough for audio stuff.
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    Here's a tested working solution for your current...

    Here's a tested working solution for your current problem.
    1/ Ditch transistors Q1 and Q2 and surround resistors.
    2/ Run each LED in series with a 1k-4k7 resistor and in parallel with the...
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    These readings are very odd. If looks like your...

    These readings are very odd. If looks like your transistors are not working and are in between on and off state because if they are completely off you should have around 12V at the collector and...
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    What I see on the schematic at first glance is...

    What I see on the schematic at first glance is even with the channel switch in the middle both Q1 and Q2 that are already 'on'. One of them will be always on of that's why your crunch LED will also...
  20. I don't think reactive loads are bad per se...

    I don't think reactive loads are bad per se otherwise a lot more people would have complained over the years which is not the case. Also bigger companies wouldn't have jumped on that train either....
  21. Key word is "typically".

    Key word is "typically".
  22. 14.3VDC is too low for a regular 7812. My advice...

    14.3VDC is too low for a regular 7812. My advice is to replace the 4007 with Schottky diodes (like 1N5819 for example) to minimize the voltage drop. Even better would be also to replace the 7812 with...
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    I'm usually using a common type like BC546B or...

    I'm usually using a common type like BC546B or BC550C. No need for fast diodes.
    Also check out Mesa amps' switching for more ideas and 'how to'.
  24. No doubt all this can be improved the question is...

    No doubt all this can be improved the question is whether for practical purposes the difference would justify the extra effort. Maybe it's one of those things that you have to try for yourself...
  25. For attenuator purposes maybe it's not necessary....

    For attenuator purposes maybe it's not necessary. In reactive load only circuits usually a 33-47Ohm resistor is used.

    Below is an impedance measurement of a real 2xV30s cab (red) vs an unloaded HF...
  26. The low frequency resonance is VERY important!...

    The low frequency resonance is VERY important! Especially when kranked a tube will generate certain harmonics in this frequency region which if not properly loaded by this inductor otherwise won't be...
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    I told you to ditch the PNP stuff :D

    I told you to ditch the PNP stuff :D
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    The biggest pop usually comes from relays...

    The biggest pop usually comes from relays connected to grids, especially in high gain circuits. This is almost unavoidable that's way they all have mute circuits.

    The other thing that looks very...
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