Powerhead Amplifier

    I recall having seen a link somewhere to another site that links to the manufacturer's site of the actual amp used in the Powerhead, but darned if I can find it. Couldn't find it in the Wiki either. There were some posts that mention a B&O amp but I seem to recall it was something else. Anyone know where it is? Thanks!

    Never mind, I found the answer... from ck himself...


    Quote from ckemper

    You are right, I said that.
    The protection circuits do not act properly at 4 Ohm, that's why we do not recommend it.
    Still it's possible, but do not run too high volumes, otherwise you will break the power amp.

    Some info from the datasheet for the Icepower 1000A amplifier, for information only:


    PO Output power @ 0.1%THD+N
    10Hz < f < 1kHz (AES17 measurement filter):
    1000W RL=4Ω, Vp =120V
    800W RL=6Ω, Vp =120V
    600W R =8Ω, Vp =120V

    f Frequency response 20 – 1kHz, all loads ±0.5 ±1 dB
    fu Upper bandwidth limit (-3dB), RL = 4Ω: 3 kHz
    fl Lower bandwidth limit (-3dB), RL = 4Ω: 4 Hz
    Zo Output impedance f = 1kHz : 5 typ/10 max mΩ
    ZL Load impedance range 2 Ω min /4 Ω typ
    D Dynamic range A-weighted 120 dB


    And a VERY important caveat:


    Warning! The balanced speaker outputs are both “hot” with a common-mode DC level equal to Vp/2. Always
    use balanced probes for monitoring and measurements. Shorting one of the terminals to ground results in an
    over current situation. As the module has no internal current limiter even a brief short circuit (phase-to-phase or
    phase-to-GND) will damage the device beyond repair. Current limiting circuitry must be connected externally.


    CK says that the protection doesn't work properly at 4 ohms. So it would be wise to avoid going below 8 ohms. Caveat emptor. :-0

    Wow, that sucks if you're a bass player or use a 4 ohm full range monitor for guitar (me = both). 1000w @ 4ohms would have been more than perfect.


    I can't believe that have that in their specs, yet the protection circuit doesn't work at 4 ohms. Did someone say Accusation Switch? (a little Accugroove joke ) :D


    So I take it the protection circuit is in the power amp right, not a Kemper feature?


    I think I'm going to email B+O and see whats up with their false advertising. Imagine if Matrix did that! Hopefully they'll upgrade their amp one day to a working spec.


    edit: from reading the 1000A pdf, it doesn't have a thermal shutdown feature built in, so if the protection circuit is covering that, that's from Kemper's end. Which sounds like it's Kemper's protection circuit to blame, not the 1000A... :cursing:



    1000A

    Edited once, last by Bevosss ().

    Quote from viabcroce

    If you need massive amount of SPL and a huge impulsive power then I'd go for an external amp aimed at amplifying an electric bass :)


    I don't need either...just an amp that can do 4 ohms safely, like most bass players use. And apparently the 1000A IS capable according to their specs. So, disappointing, still have to lug around extra iron....