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power amps
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Hi there, its me again with the not so bright questions. If I a a power amp to my receiver, does my receiver then works only as a processor? In other words if my receiver is 100wpc and the power amp is 75wpc, does this mean 175wpc of power is sent to my speakers or is it only the power of the power amp? When one adds a power amp does the wattage of the receiver become futile? Pls educate me. Thanks.

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RE: power amps

Hello,

 

When you add a poweramp, you bypass the receiver's internal amplifier modules. So the 75watts poweramp from you example will be what feeds your speakers: 75watts.

But, you can also add a poweramp like I did in my system: I use my stereo amp (pm15) as a poweramp for the front left and right channels of my receiver (nr1402). The receiver still powers the centre and rear speakers, but the fronts are looped through my stereo amp. That way, the receiver does all the processing, but only powers 3 channels, where as the stereo amp works as a poweramp to power the fronts.

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Thanks kevin, I think that's

Thanks kevin, I think that's what I might have to do cos my integra is very powerful in 5.1 but in stereo its a bit dissapointing. Now when u have both the stero power amp and receiver working together, which volume controls the sound? If I'm watching the a movie, will I still need to switch the stereo amp on? Pls excuse my ignorance.

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RE: power amps

If you add a power amp to your AV receiver, for say the front channels, then set up is relatively straight forward. The input level to the power amp is fixed, so all you need to do is turn on both amps, run the test signal and adjust the levels accordingly so they are all at the same level. You only do this once, then every time you turn both amps on the levels are set, and you just use the AV receivers volume control.

 

Using an integrated instead of a power amp is the same in principal, but a bit trickier as the integrated also contains a pre amp section which you need to adjust. You connect the pre outs for the main channels to a spare line input on the integrated amp (eg Aux or AV, or CD even). Then select that input and set the volume on the integrated to about 12 o'clock (be careful, any other source played at this volume accidentally would blow your head off nearly!). Turn the AV receiver on to a low volume, and play the test tone, adjusting the levels so all 5 channels are equal in volume. You then just use the AV receiver volume control for the whole system. Again the levels test tone setting is only done once. Next time you go to watch a movie, you turn your integrated on, select the line in from the AV receiver, set the volume to 12 oclock, then gradually increase the AV receiver volume to your desired listening level.

 

The difference is basically setting the integrated to 12pm to replicate the same input level as a power amp would have.

The above (integrated amp) is exactly how I run my system, as it sounds great for both music (no AV amp in the way) and movies ( AV amp for processing and centre and rears, quality integrated for fronts). You will also see I have the added complication of an additional power amp to help my large front speakers  Laughing

 

Sorry for the long post, hopefully some of it makes sense!

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RE: power amps

Having re-read my ramblings, it's a good idea to state the principal of why you would go to all this trouble. 

Home Cinema amps are great at Home Cinema but often lacking when it comes to 2 channel music (often sounding quite thin).

If you use the system I described in my post, you feed all your music sources straight into your dedicated integrated stereo amp and ignore the home cinema receiver for music. When you want to watch a movie, you simply introduce the Integra into the loop.

Downsides is it adds another box and a few more switches to toggle before you can play anything (something my misses struggles to work out)

Just adding a power amp is a bit easier as you still have everything going through the Integra and do all your source selection etc through there, and simply turn on the power amp. Downside is that you are using the pre amp in the integra, which is normally not as good as the pre amp in a decent integrated for music.

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RE: power amps

gees, nlanks, thank God for your second post cos after your first post i went to bed feeling like such an idiot. is there a difference between an integrated amp and a power amp?  im still not sure which power goes to my speakers when i add a power amp - i know kevin mentioned that its only the power amp that 'slaves'.  i think i should just lookout for a 5 channel power amp, i trust this will help with my thin sounding music as well.  I recently missed out on a linn 5 channel power -demo-selling at 25% of its original price.  guys i appreciate all your responses but im still not sure where to go from here.  i need more power to my fronts!!!! oh can i biwire my speakers if i add a 2 channel amp?:help: :help: :help:

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RE: power amps

I all depends on what you want to add to your system: a stereo integrated amp, or simply a poweramp.

A stereo integrated amp is built up by a pre amp and a poweramp. The pre amp does all the source switching, tone controls and volume settings, the poweramp simply adds the power to drive the speakers.

A poweramp is nothing more than a big box that adds power to drive the speakers. No switching, no tone controls, nothing. And most of the time only has an ON/OFF switch.

 

Adding a poweramp is the easy way to upgrade the power of any stereo integrated or av receiver, if that one comes with a pre out (most av receivers do, not all stereo integrated amps do). But like Nlanks also said, if you only add a poweramp, you'll keep using the pre amp section of your Integra receiver to do all the volume/tone controls/....

 

If you want to add an integrated stereo amplifier, you can connect it the way Nlanks explained above (if it doesn't have a "power amp direct" switch).

The stereo integrated amp that I use (marantz PM15S2), can be used in 3 different ways: as a simple stereo integrated amp (pre and power amp combined, no other boxes needed), as pre amp (needs a power amp to work, or powered speakers) or as power amp (needs a pre amp to change volume, input,...).

So when I want to listed to stereo music, I just turn on my PM15, make sure it's in "regular stereo integrated amp" mode, and use it like any other stereo integrated amp.

When I want to watch a movie, I turn on my av receiver (nr1402) and my PM15. But I push the "power amp direct" switch on the PM15, so it only works as a poweramp. That way, the NR1402 controls the volume/tone controls/... and the PM15 only amplifies.

 

But I must add I've always found that a pre amp changes the tonal/musical signature more than a poweramp. So you might want to try before you buy and make sure it does what you want it to do.

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RE: power amps

Sorry about that! I read integra as integrated, hence why I went off on that route!

An integrated amplifier has two main parts:

A pre amp section - which is where you control which source you want playing, what level you want it to output (volume). These are what all the knobs do on the front of most hi fi amps.

And a Power Amp section - this is where the actual amplification is done, think of it as the muscle of the system.

Your Integra 30.3 is no exception:

The pre amp section allows you to select which source you listen to and control the volume. It also does the decoding etc.

The power amp section then beefs up the sound and sends it to the speakers. In your case 5 of them.

If you add a power amp for a certain channel (eg fronts) then you are using the pre amp in the Integra, but the external power amp for that channel. The two front speakers are then wired up from the power amp. Thus the speaker terminals on the back of your Integra for the front speakers are no longer connected to anything. To go back to your original scenario, the 100watts in your integra for the front channels are now redundant, and the 75watts that the power amp has is in use instead. Your rear and centre speakers are still connected to the Integra though and using its 100wpc power for their channels.

Another way to look at it is that you connect the power amp to the "Pre Out" sockets on the back of your Integra. These basically mean "Pre Amp output". What would normally be sent to your internal power amplifier is also being sent to your external power amp

 

I think your best solution to try and improve music playback would be to add a 2 channel stereo power amplifier, to power the fronts. This will definitely be the simplest too.

 

Dont get a 5 channel power amp, you simply don't need one. The other 3 channels it gives you are unnecessary, as your integra is more than capable of powering these. Also, these 3 channels (centre and rears) are not used when playing stereo music, so won't help you there. 5 channel amps are usually the domain of high end systems, where serious power is needed all round, and thus are expensive.

If you don't mind buying second hand from eBay, my advice would be to try and get hold of a decent 10ish yr old 2 channel power amp from there and give it a go. If you feel it does nothing for your set up, or you don't like the new sound, you'll almost certainly be able to resell it for what you paid (check previous sales first to get an idea of avg selling price).

I only ever recommend stuff I've heard, and so would advise to try something like the Arcam Alpha 8p, 9p or 10p, depending on budget (looking around £100, £175 and £250 respectively). If you dont mind going older, there are always plenty of Audiolab 8000p available around the £200-250 mark.

 

Finally, yes you can always bi-wire your speakers from any amp. If the amp has two sets of speaker outputs then you use one pair to the treble and the other pair to the bass. If your amp has only one set of speaker outputs, you simply take both treble and bass feeds out of the one set (so 2 wires into each connector). If you buy this cable new from your local dealer he will be able to put the right connections on it for you. Most important thing to remember when bi-wiring is to remove the metal link plates that join the two sets of terminals on the back of the speaker (as you are now feeding each on independently). You will create a short circuit if you don't. Google bi-wiring and you should see plenty of diagrams regarding all the above.

 

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power amps

Nlanks and kev, the effort and time u have put into assisting me isso appreciated. What I did not mention is that I still have my old sony 1200es so my local dealer sold me a pair of rca cables and he will send one of ghis guys over to "loop" my integra and use my old sony receiver to drive my fronts (stereo). No disrespect to integra its very powerful with movies but in stereo it needs help esp cos I dnt use my sub wen playing music. Once again guys thank you so so much.

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RE: power amps

My pleasure  Smile

Thats good he's coming over to help, nothing beats listening to it.

I would think though (but obviously I'm not there to hear it!) that just using the 1200es for poweringnthe fronts may be a bit of a waste of that machine, and be a bit complicated to set up and use each time.

I would think you would be better off selling the 1200es and using the money to buy one of the dedicated stereo power amps I mentioned.

If you like how it sounds later though, problem solved!

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power amps

Well the expert came over yesterday, well just to press a few buttons since I had correctly connected everyting, just didn't switch to analogue on integra. Decided to amp all 5 speakers thru the sony and boy now it sounds like my speakers are amplified. IT CRACKS!!! My speakers are sweating!!! Not only is it loud, it just sounds powerful! Man I'm so pleased, funny thing tho is both volumes are working independently and I doubt I will hear how loud this combination can get but damn it sounds good. Mission so accomplished. I'm just beside myself right now, unbelievable sound in my lounge!!!

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RE: power amps

That's great Rayray, enjoy!  :bounce:

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