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Discolicious
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Morning!

Apologies if this is actually a really easy question, but...

I've been using active speakers for a while now, but want to, let's say, broaden my speaker horizons! I've just bought a pair of W Audio PSR 15's (http://www.decks.co.uk/products/WAudio/PSR15), so, I want to know what amp I would ideally need to run these safely? I still can't get my head around the per channel and ohm's business (and there was me thinking I was quite intelligent!). Would I need an amp say 2 x 400w RMS at 8 ohm??

Help in layman's terms is VERY mich appreciated!! thumbup.gif

Baz
dj_dash
Right. So.

A channel is one output from the amp - most amps have two channels, typically one for the left signal and one for the right signal. There's not much more to channels than that.

The output per channel is what power you'll get from each. So your 2 x 400w = 2 channels, each producing 400w each, at 8 ohms.

You'll find that, at 4 ohms, they'll have a higher power rating, because there's less resistance. The lower the resistance/impedance on the channel, the more power it will drive.

(Although keep in mind that some think that double the resistance means half the power - it doesn't!! Always see what the manufacturer's ratings are for each impedance!)

So to answer your question - yes, an amp at 2 x 400w @ 8 ohms will do for driving your PSR-15s. :-)
Discolicious
Thanks Dash - think I'm a little clearer now! It just started to get confusing reading posts about connecting however many speakers to however many channels! I just want to connect 1 PSR15 speaker to each channel and wanted to know what amp to buy to run them without having to worry too much about under/over powering and ending up with rubbish sound!!

So much easier with actives!! haha! yes.gif



QUOTE(dj_dash @ Apr 24 2012, 11:06 AM)

Right. So.

A channel is one output from the amp - most amps have two channels, typically one for the left signal and one for the right signal. There's not much more to channels than that.

The output per channel is what power you'll get from each. So your 2 x 400w = 2 channels, each producing 400w each, at 8 ohms.

You'll find that, at 4 ohms, they'll have a higher power rating, because there's less resistance. The lower the resistance/impedance on the channel, the more power it will drive.

(Although keep in mind that some think that double the resistance means half the power - it doesn't!! Always see what the manufacturer's ratings are for each impedance!)

So to answer your question - yes, an amp at 2 x 400w @ 8 ohms will do for driving your PSR-15s. :-)

dj_dash
QUOTE(Discolicious @ Apr 24 2012, 10:14 AM)

Thanks Dash - think I'm a little clearer now! It just started to get confusing reading posts about connecting however many speakers to however many channels! I just want to connect 1 PSR15 speaker to each channel and wanted to know what amp to buy to run them without having to worry too much about under/over powering and ending up with rubbish sound!!

So much easier with actives!! haha! yes.gif


Yes. Yes they are!

Connecting multiple speakers to one output changes the resistance on the channel, which is why that gets a bit more complicated.

The PSR-15s are rated at a good 1400w peak and 350w RMS I believe, so running a 400w RMS amp should sit pretty with them. Generally speaking, some folks would say if it's a 350w RMS speaker, stick no more than a 350w RMS amp through it. But at 400w RMS per channel, I'd be very surprised if you blow anything up tongue.gif
Discolicious
Haha! I'd hope not!

I was going with the school of thought that having an amp slightly bigger rated than the speaker meant that you wouldn't have to push the amp as hard, therefore keeping it a bit cooler and ddecreasing the chance of that blowing. Obviously you don't want too much extra RMS or else you'd end up blowing the speakers instead!

Think I'm getting somewhere now! Cheers Dash!!!! amen.gif

QUOTE(dj_dash @ Apr 24 2012, 12:07 PM)

Yes. Yes they are!

Connecting multiple speakers to one output changes the resistance on the channel, which is why that gets a bit more complicated.

The PSR-15s are rated at a good 1400w peak and 350w RMS I believe, so running a 400w RMS amp should sit pretty with them. Generally speaking, some folks would say if it's a 350w RMS speaker, stick no more than a 350w RMS amp through it. But at 400w RMS per channel, I'd be very surprised if you blow anything up tongue.gif



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