Dr Z PowerBrake Lite

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GassageGassage Frets: 30826
edited February 2017 in Amps
Just plugged one into my DR103.

Cranked the monster.

Smoke pouring out of attenuator!

I suspect it needs lesser output into it.

@riftamps measured the Hiwatt as 214w when cranked. Maybe a tad too much.

*An Official Foo-Approved guitarist since Sept 2023.

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Comments

  • hywelghywelg Frets: 4302
    edited February 2017
    Yeah, they're rated to about 30watts.

    Fried, sautéed,  toasted and other food based analogies. 
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  • shaunmshaunm Frets: 1591
    Oh dear
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  • GassageGassage Frets: 30826
    Now it's been toasted, will it work with my Lazy J?

    Mind you, cranked, the Hiwatt was just fucking flabbergastingly good. Real crunch, a new facet to it.

    *An Official Foo-Approved guitarist since Sept 2023.

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  • ICBMICBM Frets: 71960
    That was a bit silly ;).

    Unwise to use it with any other amp until it's been checked over. If you're lucky you might just have burned the coating off the resistance element - the actual winding itself is quite thick wire so it might have survived fairly undamaged. You'd probably know if you'd actually burned out the element since you would have got sudden silence and then most likely a nasty burning smell coming from the amp...

    To be honest the supposed 45W rating of these is quite optimistic - I wouldn't even use one with a Tweed Bassman. As hywelg said, about 30W max.

    For what it's worth I wouldn't even use a full-size Airbrake with a DR103 - the minimum I would think safe would be a Marshall Powerbrake, THD Hotplate or the Weber Mass 200 (not any of the smaller models) or something else that's definitely rated for the full output of a 100W+ amp.

    "Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski

    "Just because I don't care, doesn't mean I don't understand." - Homer Simpson

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  • Chris of Riftamps has just made an attenuator for me . Strictly nothing above 25w though. At least I'll know what will happen if I did now.

    Thanks :)
    Link to my trading feedback:  http://www.thefretboard.co.uk/discussion/59452/
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  • CirrusCirrus Frets: 8481
    edited February 2017
    ICBM said:
    That was a bit silly .

    Unwise to use it with any other amp until it's been checked over. If you're lucky you might just have burned the coating off the resistance element - the actual winding itself is quite thick wire so it might have survived fairly undamaged. You'd probably know if you'd actually burned out the element since you would have got sudden silence and then most likely a nasty burning smell coming from the amp...

    Out of interest, what's the deal when you're only knocking some volume off? If you'd rate it around ~30watts, does this mean if you only ever used it on the first or second settings it'd hold up with a higher wattage amp, since presumably it's doing less by way of turning the Comfortably Numb solo into heat?

    Then again I suppose that even just -3dB is going to be half the energy output of the amp turning into heat...
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  • GassageGassage Frets: 30826
    ICBM said:
    That was a bit silly ;).

    Unwise to use it with any other amp until it's been checked over. If you're lucky you might just have burned the coating off the resistance element - the actual winding itself is quite thick wire so it might have survived fairly undamaged. You'd probably know if you'd actually burned out the element since you would have got sudden silence and then most likely a nasty burning smell coming from the amp...

    To be honest the supposed 45W rating of these is quite optimistic - I wouldn't even use one with a Tweed Bassman. As hywelg said, about 30W max.

    For what it's worth I wouldn't even use a full-size Airbrake with a DR103 - the minimum I would think safe would be a Marshall Powerbrake, THD Hotplate or the Weber Mass 200 (not any of the smaller models) or something else that's definitely rated for the full output of a 100W+ amp.
    ICBM,

    8Ohm Hotplate?

    *An Official Foo-Approved guitarist since Sept 2023.

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  • ICBMICBM Frets: 71960
    Cirrus said:

    Out of interest, what's the deal when you're only knocking some volume off? If you'd rate it around ~30watts, does this mean if you only ever used it on the first or second settings it'd hold up with a higher wattage amp, since presumably it's doing less by way of turning the Comfortably Numb solo into heat?
    No. Despite what some attenuator makers say it's never really safe to assume that.

    Cirrus said:

    Then again I suppose that even just -3dB is going to be half the energy output of the amp turning into heat…
    Exactly. And at -6dB, three-quarters of it - which is as close to all as makes no practical difference for a resistor power rating really, since for safety you should aim for a 2:1 margin.

    Gassage said:

    8Ohm Hotplate?
    If you have one, yes. If you don't, I'd get a 16. Like Marshalls, Hiwatts will get a bit stressed running flat-out into a Hotplate, and the way to fix that is to deliberately mismatch it so the amp is set to one step below the Hotplate - ie 8 ohms on the amp into a 16-ohm Hotplate or 4 ohms for an 8-ohm one. This is because the Hotplate's impedance curve dips at high frequencies so it's lower than a real speaker.

    "Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski

    "Just because I don't care, doesn't mean I don't understand." - Homer Simpson

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  • @Gassage - why are you always blowing the gear you get from me? Guess I shouldn't accept any more money from you as I've started feeling bad now :)
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  • The Marshall attenuator is probably better suited to the Hiwatt
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  • IvisonGuitarsIvisonGuitars Frets: 6838
    tFB Trader
    YOU TIT.
    http://www.ivisonguitars.com
    (formerly miserneil)
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  • Make your own attenuator like I did. Well I got someone to do it for me lol
    Link to my trading feedback:  http://www.thefretboard.co.uk/discussion/59452/
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  • GassageGassage Frets: 30826
    ICBM said:
    If you have one, yes. If you don't, I'd get a 16. Like Marshalls, Hiwatts will get a bit stressed running flat-out into a Hotplate, and the way to fix that is to deliberately mismatch it so the amp is set to one step below the Hotplate - ie 8 ohms on the amp into a 16-ohm Hotplate or 4 ohms for an 8-ohm one. This is because the Hotplate's impedance curve dips at high frequencies so it's lower than a real speaker.
    So ideally, 8Ohm, if not 16Ohm, right?

    *An Official Foo-Approved guitarist since Sept 2023.

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  • GassageGassage Frets: 30826
    edited February 2017
    And THD or the full fat Dr z?

    *An Official Foo-Approved guitarist since Sept 2023.

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  • ICBMICBM Frets: 71960
    Gassage said:
    And THD or the full fat Dr z?
    The THD would be OK, the Airbrake not.

    Gassage said:

    So ideally, 8Ohm, if not 16Ohm, right?
    Yes - 8 or 16 ohm. I know you want the 8 really because its purple :).

    "Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski

    "Just because I don't care, doesn't mean I don't understand." - Homer Simpson

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  • GassageGassage Frets: 30826
    tone1 said:
    No; that'll just melt like the Dr Z.

    *An Official Foo-Approved guitarist since Sept 2023.

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  • ThorpyFXThorpyFX Frets: 6090
    tFB Trader
    ICBM said:


    Gassage said:

    8Ohm Hotplate?
    If you have one, yes. If you don't, I'd get a 16. Like Marshalls, Hiwatts will get a bit stressed running flat-out into a Hotplate, and the way to fix that is to deliberately mismatch it so the amp is set to one step below the Hotplate - ie 8 ohms on the amp into a 16-ohm Hotplate or 4 ohms for an 8-ohm one. This is because the Hotplate's impedance curve dips at high frequencies so it's lower than a real speaker.
    I never knew that..... that is a good bit of knowledge to have.
    Adrian Thorpe MBE | Owner of ThorpyFx Ltd | Email: thorpy@thorpyfx.com | Twitter: @ThorpyFx | Facebook: ThorpyFx Ltd | Website: www.thorpyfx.com
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