• 03-12-2004, 11:39 PM
    nusiclover
    please explain OHMS to me. thanks
    ok, my av receiver (marantz 6400) says it is capable of hadling 6 to 8 ohm max loads. Hoever, my speakers are rated at 4 ohms. Is this ok to use together? What does it all mean?
  • 03-13-2004, 01:32 AM
    nusiclover
    please help me figure this out
    ohms and impedance what does it all mean. i am runnnig 4 ohm speakers into my marantz sr6400. is this ok? what does it all mean? whats going to happen when i set up the center and surrounds?

    marantz sr6400
    dynaudio 52
  • 03-13-2004, 02:40 AM
    msrance
    Resist the temptation to mismatch resistance!
    Quote:
    Originally Posted by nusiclover
    ohms and impedance what does it all mean. i am runnnig 4 ohm speakers into my marantz sr6400. is this ok? what does it all mean? whats going to happen when i set up the center and surrounds?

    marantz sr6400
    dynaudio 52
    Hello nusiclover, Ohms is the quantitative equivalent of a resistance when put instead of the said speaker would offer same amount of impedence to current flow.

    Resistance is - what it means in plain english - a resistance that the substance( a speaker, in this case) offers to flow of electrons (that is current). When taking a DC (direct current) into consideration - its called resistance - and the same resistance is called impedance when in context of alternating current (AC). They are measures in a unit called ohm.

    fair and simple till now. now we consider an equation "V=IR" ( where V is the voltage in volts, I is the current in amperes and R is the resistance in ohms). Again pretty simple, The voltage in a country is a constant (ideally speaking) - 110 for USA, 220 in India and so on. R is the resistance of the speakers (4 ohms in your case). I is the current that will be generated.

    so I = V / R

    That makes resistance inversely proportional to the current. Higher the resistance lower the current and higher the current - lower the resistance. I guess thats pretty clear now.

    Now you must be wondering why this physics lecture for a simple question you asked!! Lets explain that now - The higher the current ( that means lower resistance) the more will be the heat produced when the current travels through wires and various parts of your amplifier.

    Your amp is built to handle 6 / 8 ohms of resistance only - that means when you put lower resistance speakers onto the amp - more current passes through it and may cause over heating and hence damage some part of the amp permanently. With a good amp like Denon or Yamaha or Marantz or NAD or any of the big guns - the overheat protection circuitry will cut off the power before any damage occurs - but then you are putting yourself at the mercy of another circuitry that is about as vulnerable to damage!

    I hope this clears your doubts on the matter. Now lemme tell you one more thing - i learnt all this in this very forum! and I still run my 8 ohm at an average impedence of 2.67 ohms - and I have been recently asking people why does my amp sound harsher than before in just 6 months? So dont make the mistake of pushing your luck too far ! Enjoy the good music!

    also keep in mind the fact that the impedence keeps constantly changing with the frequency - and with the music playing - resistance of a 4 ohm speaker may fall below 2 ohms momentarily or go beyond 4 at certain times!
  • 03-13-2004, 04:23 AM
    F1
    Quote:
    Originally Posted by nusiclover
    ok, my av receiver (marantz 6400) says it is capable of hadling 6 to 8 ohm max loads. Hoever, my speakers are rated at 4 ohms. Is this ok to use together? What does it all mean?
    It should be ok as long as you don't play it very loud. When you run lower impedance speaker your receiver is warmer than if you run higher impedance speaker. Anyway the receiver protection will turn on when you are driving your speaker too hard so you know when to turn it down. Speaker impedance rating is a nominal value. The actual impedance fluctuates depending on frequency.
  • 03-13-2004, 12:08 PM
    nusiclover
    so....
    do you think i should consider replacing the receiver? because when i finally get around to having 5.1 i will be running 5 dynaudio speakers which more than likely will be 4ohm/each. thanks for helping me out with this.
  • 03-13-2004, 02:09 PM
    msrance
    Quote:
    Originally Posted by nusiclover
    do you think i should consider replacing the receiver? because when i finally get around to having 5.1 i will be running 5 dynaudio speakers which more than likely will be 4ohm/each. thanks for helping me out with this.
    You would have to decide for yourself. But thats for sure that you will have to either play it real low. and if you turn it up and the protection circuit intervenes to stop damage, still in a movie there would be some scenes with lots of high SPL audio backdrop soundeffects. These might trigger a protection cutdown even at low volumes.