The Official Wilder Amplification Tech Article Thread

Discussion in 'The Workbench' started by Wilder Amplification, Apr 12, 2010.

  1. Wilder Amplification

    Wilder Amplification New Member

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    Re: The Official Wilder Amplification Amp School Thread

    http://www.marshallforum.com/workbe...lel-circuits.html?highlight=parallel+circuits
     
  2. fastdave

    fastdave Member

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    Re: The Official Wilder Amplification Amp School Thread

    Wilder, here's no way anyone can pay you what you're worth, and all the business and bureaucrat idiots who think they have something because they like sums and money couldn't hold a candle to you - they should f g worship you.
    Dave
     
  3. Les Moore

    Les Moore Well-Known Member

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    You have a nice way of explaining these things so that anyone can understand. Read some tube posts you wrote. Great job!
     
  4. MajorWatt

    MajorWatt New Member

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    You damn right i'm retarted............:slash:
     
  5. Heritage Softail

    Heritage Softail New Member

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    I tried to go to the Wilder Amplification site to see about mods and prices.

    No Mas...

    So sad.

    I have a DSL and like it. Would like to have it modded to be more gig friendly. Move buttons to a foot switch and add choke, other options. Add tone shaping between effects return and power section to be able to tweak the tone when the DSL is a slave amp.

    Please advise of a link or preferred method of contact.

    Thanks
     
  6. Wilder Amplification

    Wilder Amplification New Member

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    Hi there.

    We have a new site. It's still a work in progress at the moment, but here is the link -

    Wilder Amplification - Home Page

    You can also email us at wilderamplification@gmail.com
     
  7. Jaymz E

    Jaymz E Well-Known Member

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    what is the reason some techs (VOODOO AMPS) hardwire the ohms selector on older marshalls? Does it sound better?
     
  8. Wilder Amplification

    Wilder Amplification New Member

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    Doesn't sound any better, but it eliminates the chances of having a switch cause an open load condition if it loses contact.

    Ideally to hardwire the taps in a way that offers the possibility of hooking up every imaginable speaker configuration you would need a total of 5 jacks to do it. 1x16 ohm, 2x8 ohm and 2x4 ohm. Then you would have to remember which jack to plug everything into in order to hook everything up correctly.
     
  9. Jaymz E

    Jaymz E Well-Known Member

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    Thanks a lot for your valuable reply, I have (2) 300 watt 1960 lead cabs set to 16 ohms mono. VOODOO Amps say use 8 ohm jacks on the amp - one 8 ohm jack for one cab, two 8 ohm jacks for both cabs and not to use the 4 ohm or 16 ohm jacks. Does this sound right to you? They sent me worn out tubes with my '74 super lead 100 and it sounds over distorted (even at lower settings) and it ain't nowhere near as loud as it was before. I had the amp converted to el34s and new filter caps, no gain mods
     
  10. Wilder Amplification

    Wilder Amplification New Member

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    No it doesn't sound right to me. Use the following configuration -

    1x 16 Ohm Cab - 16 Ohm jack

    2x 16 Ohm Cabs - Both cabs into 8 Ohm jacks

    1x 8 Ohm Cab - 8 Ohm jack

    2x 8 Ohm Cabs - 4 Ohm jacks

    1x 4 Ohm Cab - 4 Ohm jack

    1x 16 Ohm Cab with 1x 8 Ohm Cab - 16 ohm cab to 8 ohm jack/8 ohm cab to 4 ohm jack
     
    Jaymz E likes this.
  11. Jaymz E

    Jaymz E Well-Known Member

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    Thanks again... Would connecting one Marshall cab (16 ohm mono) in one of the 8 ohm jacks hurt the amp since the Imp. selector is disabled? What would be a good bias setting for a '74 100watt super lead with el34s while trying to preserve tube life?
     
  12. Wilder Amplification

    Wilder Amplification New Member

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    The valves definitely won't like it. While they may not fail right away, it can definitely shorten valve life and cause them to fail. There is always the risk of other components being damaged anytime valves fail in an amp.

    I don't take plate current any higher than 35mA. If biasing via a 1 ohm cathode resistor, anywhere from 35-40mV will yield good tone while maximizing valve life.
     
  13. Jaymz E

    Jaymz E Well-Known Member

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    Do I use the 16 ohm jack even with the imp. selector disconnected on my super-lead? Thanks again for your time.
     
  14. Jaymz E

    Jaymz E Well-Known Member

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    What happens to an amp that has the imp. switch removed? Does the jacks work different? Cant figure out why (voo-doo) told me to use the 8 ohm jacks? I really value your advise , You are a true Amp Guru. The Marshall forum is like taking an online course for free, very educational.
     
  15. Wilder Amplification

    Wilder Amplification New Member

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    The transformer has 4 wires on the secondary (the output side of it). One of these wires is the "common" wire. The other 3 are your 4, 8 and 16 ohm wires.

    You can hook them up with either an impedance selector OR you can wire each of the 3 wires to their own dedicated jack(s). They don't work any differently, you just have a dedicated jack for each wire instead of a switch.

    From what you're describing, it appears as if they disconnected the impedance selector switch and wired each of the 3 wires to their own jacks.

    So now I have a question for you - how many speaker jacks does your amp have?
     
  16. Jaymz E

    Jaymz E Well-Known Member

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    My super lead 100 has 4 speaker jacks, one 4 ohm, two 8 ohm, and one 16 ohm. The layout from right to left is 4, 8, 8, and 16 ohm. They said they hardwired it because the switch can easily fall out while in use and cause damage to my amp. At first they said use 8 and 4 ohm jacks with both of my Marshall cabs, when I tryed this it blew a fuse. I called them back and the girl answering the phone told me that Trace said use both 8 ohm jacks when using both cabs which are both 300 watt with Celestion GT 75s both are angled
     
  17. Jaymz E

    Jaymz E Well-Known Member

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    Mr. Wilder do you do repair and mod work? I think I'll send you my amps when they need serviced. I honestly choose VooDoo because it was closer to me and cheaper on shipping. I am starting to regret it. What kind of amps do you build? Its getting closer to Tax time and I will be searching the market for a new amp soon. Thank you again for taking the time to answer my questions. There are no techs in this one horse town. Good PC techs but nobody nows anything about tube amps.
     
    Last edited: Nov 18, 2012
  18. Wilder Amplification

    Wilder Amplification New Member

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    OK now it makes a bit more sense.

    When using 2x 16 ohm cabs, your total load impedance is 8 ohms. Therefore, you plug both cabs into the 8 ohm jacks. This is when running both cabs only.

    When using only 1x 16 ohm cab, you plug it into the 16 ohm jack.

    And yes, they're right about the old plug style impedance selector falling out. However, I've done retrofits on older Marshalls with the new rotary switch style impedance selector.
     
  19. Jaymz E

    Jaymz E Well-Known Member

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    Jon, I just purchased an Alessandro dual bias meter, I am wanting to bias my '74 Marshall super lead 100, How does one bias pot adjust all four tubes? What do you think about the Alessandro bias meter?
     
  20. Wilder Amplification

    Wilder Amplification New Member

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    I don't have an opinion on any bias meters as I've been doing all my biasing via multimeter since I got into valve electronics.

    One pot adjusts all 4 at once. Typically when you purchase power valves they come as a matched set. This means they should all be drawing roughly about the same idle current when no input signal is present. They won't be exactly on the same numbers though, but they will be close. So you have to look at what each valve is drawing, and bias it so that the one with the highest reading reads no greater than 70% of its rated plate dissipation. The other valves will come in slightly below that.

    Keep in mind that 70% is not a "must be set to this value" rating. It is a maximum "do not exceed" rating. This means you can bias below 70% if you think the amp sounds better there. I don't recommend biasing right at 70% anyway and usually recommend to bias between 60-65% to leave a "cushion" for wall voltage variations.
     

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