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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Lounge => Topic started by: Brendon Lundstrom on July 28, 2011, 06:28:44 pm

Title: Pa speakers Ohms serial hookup
Post by: Brendon Lundstrom on July 28, 2011, 06:28:44 pm
im supossed to post as my name but not sure how too ?

B.M.Lundstrom << :)

hi i have just got a coupla new Speakers for our practice room..
a few questions :)

300w @8 ohms
On the back are two inputs does this mean i can run output into one then out from 1st speaker into the next  freing up a a chanel on power amp .
so then is this a standard serial or parrallel setup .. wil i be doubling the ohmage or halfing it ?
and this also means that the wattage will be shared so i couyld run a 500 watt amp to the two 300 watt speakers ?
Title: Re: Pa speakers Ohms serial hookup
Post by: Lee Buckalew on July 28, 2011, 06:34:15 pm
hi i have just got a coupla new Speakers for our practice room..
a few questions :)

300w @8 ohms
On the back are two inputs does this mean i can run output into one then out from 1st speaker into the next  freing up a a chanel on power amp .
so then is this a standard serial or parrallel setup .. wil i be doubling the ohmage or halfing it ?
and this also means that the wattage will be shared so i couyld run a 500 watt amp to the two 300 watt speakers ?

I was going to answer and then...I noticed your name, I don't see it.
An admin will be along soon to ask you to use your real full name as your displayed name (or just change it before they get to it and save them the trouble).
Make the change and we'll be happy to help.

Lee
Title: Re: Pa speakers Ohms serial hookup
Post by: Brendon Lundstrom on July 28, 2011, 06:40:55 pm
I was going to answer and then...I noticed your name, I don't see it.
An admin will be along soon to ask you to use your real full name as your displayed name (or just change it before they get to it and save them the trouble).
Make the change and we'll be happy to help.

Lee

I have added my name in the original post :)
i will sort out how to change my display name when i can find how to do so thanks :)
Title: Re: Pa speakers Ohms serial hookup
Post by: Lee Buckalew on July 28, 2011, 06:48:13 pm
im supossed to post as my name but not sure how too ?

B.M.Lundstrom << :)

hi i have just got a coupla new Speakers for our practice room..
a few questions :)

300w @8 ohms
On the back are two inputs does this mean i can run output into one then out from 1st speaker into the next  freing up a a chanel on power amp .
so then is this a standard serial or parrallel setup .. wil i be doubling the ohmage or halfing it ?
and this also means that the wattage will be shared so i couyld run a 500 watt amp to the two 300 watt speakers ?

The two connectors on the back are connected in parallel with each other.  This means that any speakers you connect will also be in parallel.
If you have 8 ohm nominal speakers having two linked through the speaker jacks as you were asking would result in a 4 ohm nominal load to the amp.
As far as a 500 watt amp to the two 300 watt speakers.  It depends...on what the 300 watt rating really is and on the amplifier being rated at 500 watts at 4 ohms.

Lee
Title: Re: Pa speakers Ohms serial hookup
Post by: Brendon Lundstrom on July 28, 2011, 06:53:43 pm
im supossed to post as my name but not sure how too ?

B.M.Lundstrom << :)

hi i have just got a coupla new Speakers for our practice room..
a few questions :)

300w @8 ohms
On the back are two inputs does this mean i can run output into one then out from 1st speaker into the next  freing up a a chanel on power amp .
so then is this a standard serial or parrallel setup .. wil i be doubling the ohmage or halfing it ?
and this also means that the wattage will be shared so i couyld run a 500 watt amp to the two 300 watt speakers ?

so if the amp is 500 at 4ohms say 250 per channel..
then if i hook up 8 ohm speakers this increases the impeadence resulting in the watting dropping to a bit over half say about 175 per channel ?
Title: Re: Pa speakers Ohms serial hookup
Post by: Lee Buckalew on July 28, 2011, 06:59:45 pm
so if the amp is 500 at 4ohms say 250 per channel..
then if i hook up 8 ohm speakers this increases the impeadence resulting in the watting dropping to a bit over half say about 175 per channel ?

No, if the amp is 500 watts at 4 ohms and you split the wattage between two identical speakers (that are presenting a 4 ohm nominal load to the amp since two 8 ohm speakers in parallel would be 4 ohms) then each speaker can be fed 250 watts.

If instead you wanted to use one 8 ohm speaker then you'd need to know the amps output rating at 8 ohms.  There are some amps that put out the same wattage at 8 or 4 ohms so it's not wise to assume the amp will deliver different power and different impedance ratings without checking.

Lee
Title: Re: Pa speakers Ohms serial hookup
Post by: Brendon Lundstrom on July 28, 2011, 07:01:33 pm
No, if the amp is 500 watts at 4 ohms and you split the wattage between two identical speakers (that are presenting a 4 ohm nominal load to the amp since two 8 ohm speakers in parallel would be 4 ohms) then each speaker can be fed 250 watts.

If instead you wanted to use one 8 ohm speaker then you'd need to know the amps output rating at 8 ohms.  There are some amps that put out the same wattage at 8 or 4 ohms so it's not wise to assume the amp will deliver different power and different impedance ratings without checking.

Lee

ok thanks for your help much appreciatted :)