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70/100V speaker / amp questions...

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Richard Hedderly:

--- Quote from: John Roberts {JR} on December 31, 2020, 12:11:58 PM ---It is still unclear what hand you are dealt.

The behriger nx4_6000 seems like a lot of power for a church instal.

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JR

--- End quote ---

The NX4_6000 is for covering over 4 channels 440W at 8Ω. The FOH speakers are 300W working up to 600W at 8Ω. We have two smaller 8Ω speakers in a side room.

I've seen recommended that an amp have twice the power as needed so you steer clear on distortion driving it.

That said, the FOH speakers in the church are mostly vocal, with some hymn music tracks playback. We're not feeding a band through it. 440W PC should be OK. Do you think I should get 600W PC?

Also the current amp is pushing 300W PC at 4Ω into 8Ω speakers.

https://www.thomann.de/gb/behringer_nx4_6000.htm

Scott Holtzman:

--- Quote from: Richard Hedderly on December 31, 2020, 09:58:26 PM ---The NX4_6000 is for covering over 4 channels 440W at 8Ω. The FOH speakers are 300W working up to 600W at 8Ω. We have two smaller 8Ω speakers in a side room.

I've seen recommended that an amp have twice the power as needed so you steer clear on distortion driving it.

That said, the FOH speakers in the church are mostly vocal, with some hymn music tracks playback. We're not feeding a band through it. 440W PC should be OK. Do you think I should get 600W PC?

Also the current amp is pushing 300W PC at 4Ω into 8Ω speakers.

https://www.thomann.de/gb/behringer_nx4_6000.htm

--- End quote ---


Lord have mercy please don't use the word push when describing the capability of an amplifier.  Watts is truly a useless specification out of context but in no context is there any difference between two equally speced amplifiers unless power is doubled.  Amplifiers supply or source power.  They do not push anything.


I just reread the thread and I did not see the impetus of the purchase?  If the current system is broken then you will be find, of you are hoping for any audible change that is unlikely. 

Richard Hedderly:

--- Quote from: Scott Holtzman on January 01, 2021, 03:41:35 AM ---
Lord have mercy please don't use the word push when describing the capability of an amplifier.  Watts is truly a useless specification out of context but in no context is there any difference between two equally speced amplifiers unless power is doubled.  Amplifiers supply or source power.  They do not push anything.


I just reread the thread and I did not see the impetus of the purchase?  If the current system is broken then you will be find, of you are hoping for any audible change that is unlikely.

--- End quote ---

Thank you for the clarification.

The impetus of purchase is that the analogue mixer amp keeps cutting out. It is getting on for 25 years old. This plus we want to be able to have the advantage of a digital mixer, means we will require a new amplifier. The reason why 70/100V systems were brought up was because a cable with a label saying 70V was found under the church near the mixing console's cables. As discussed, this now appears to be from an old distributed system that no longer exists.

Frank Koenig:

--- Quote from: Scott Holtzman on January 01, 2021, 03:41:35 AM ---Lord have mercy please don't use the word push when describing the capability of an amplifier.  Watts is truly a useless specification out of context but in no context is there any difference between two equally speced amplifiers unless power is doubled.  Amplifiers supply or source power.  They do not push anything.
--- End quote ---

The loudspeaker is a weak, fickle, some might say floppy, creature that really doesn't know what it's about. Its (complex, very complex?) impedance varies all over the place and even is subject to things outside itself. The amplifier is the consummate, some might say brutal, voltage source, that forces its will upon the facile loudspeaker. This ultimate dominance is only attenuated by too thin speaker cables or crappy connectors. Alas, or maybe for the best, this relationship obeys conventional laws of physics and can be modeled accurately enough by assuming that the amplifier is a voltage source capable of a maximum voltage and maximum current (long-term thermal limits not withstanding). The loudspeaker can be assumed to be a resistor equal to its nominal impedance and any intervening transformers can assumed to be ideal, trading voltage for current in equal proportion perfectly. Forget about 70V, 100 V, whatever, and do the damn math. You'll be close enough.

Happy New Year. Hope we all get back to work and play soon.

--Frank

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