Hi . Would anyone be able to educate me power amplification. I am considering trying high powered class D amplification . 1000w / channel into 4 ohm. I have 84db speakers which I currently drive with 200w class a/b . Would the class D be too much power for me. I understand that the speaker only will see what ever power I feed them so I won’t be sending max power. My question is would introducing the higher powered amp, mean that turning my volume control up very slightly send high power levels. Also is there any pros and cons to having such high level of headroom ?
Sorry for suck a fundamental question
Not necessarily. The total power of an amp is not the same thing as its gain. Most power amps have a gain that usually runs from about 22-26 or so dB. Some lower, very few higher. If this new amp has the same gain as your current amp, there will be no difference in how much you turn the volume control between the two. Your speakers are relatively inefficient, so having a good amount of power is useful. As to whether there’s a problem having too much power, it all depends on the amp and the system. Some folks have commented that using very high powered amps “loses” something when it comes to low level delicacy and refinement. Personally I think that may come down to how good the amp is. Good luck.
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…and your speakers’ manual should show in the specs the recommended amplifier power range.
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More speakers are damaged by under powered amps than over powered amps.
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That was my concearn as the recommended amplification is 50-200w
Should o should be ok as long as I don’t use full capacity power?
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Unless your listening room is the size of a gymnasium, you’ll probably fracture your ears at the speaker’s rated power limit before you get anywhere close to the maximum wattage of this Class D amp.
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Yes you should be fine. Just be careful you don’t want to have any accidents.
Haha yes that’s not the plan
You ask some great questions. It might help to consider that every amplifier has not only an upper limit for the maximum voltages and currents it can supply (which is where we get the power rating) but also a lower limit of performance where its ability to accurately reproduce small inputs degrades with distortion and noise. In general, a very high powered amp connected to highly efficient speakers will have a difficult time producing quiet music that sounds good.
If you connect a power amp and speakers, and also a source or pre-amp that’s turned off, you should not be able to hear any hiss or noise at the listening position. If you can, your amp is too powerful/noisy for those speakers in that use case.
Turning on the source/pre without playing anything should also produce no audible noise. If it does, you need a quieter source/pre or a power amp with less gain.
Next, starting with the volume all the way down you can start some music and gradually raise the volume. If it gets too loud too fast, you have too much gain in the system (including the pre-amp and power amp) but not too much power per se.
Too much power is something you’ll only know about if you actually reach the physical limits of your speakers. You probably won’t be unaware of that if it happens, because either you’ll suddenly not be hearing sound that you should be, or you have just heard something that you definitely should not be.
I got lucky with my system – 500Wpc into 8 ohms and some 8-inch 2-way floorstanders, and the bass at the start of a track pushed a woofer to maximum excursion with a huge sharp “whack!” sound when the coil hit the basket. But nothing broke and it still works great. Near miss.
As somebody else mentioned you can also damage speakers by asking too much of an amp and driving it into clipping. That creates massive spikes of high-frequency energy which can blow tweeters out. Many amplifiers have some kind of overload protection built in to them to save your speakers from that fate, but some models leave them out to avoid any sonic or cost compromises. Check with your amp manufacturer to find out how your particular amp behaves. VU meters have real value for managing that risk too.
The gain on the class d had the same gain as my current amplifier (27db) so I was hoping that meant the class d amp wouldn’t have to much gain. I also check for impedance matching and everything seems good. I am very much learning and really value your detailed answer. I will definitely use the steps you suggested when trying the new amps.
you say I should connect the power amps and speakers and and turn them on and check for noise (with my sources and pre turned off)
Then turn on the source and pre and check again to see if there any noise at the speaker
And then play music from the lowest setting before turning up
Am I grasping that procedure correctly?
Thanks again 
Your preamp volume control range should then be identical or similar to what you’re used to for a given system volume.
That’s great to hear. Thank you for your insight
Absolutely true! NEVER drive an amp playing music “continuously” at full power!!!
All music contains at least 10db of dynamic peaks, some music much more! A 10db increase relates to 10X the power needs. Thus, an amp has 1/10 the power capability to CLEANLY cover the 10db Musical Peaks without Clipping (highly distorted wave-forms that destroy drivers, especially Tweeters)! For this reason, damages to speakers usually happen because of pushing a lower powered amp too loud and it clips the wave-forms into high distortion when trying to cover the musical peaks! Having high reserves of power allows the amp to cover the musical peaks…Cleanly!!
If your music genre has more dynamic 20db to 30db peaks (ex: jazz, classical, acoustic, orchestral), then you’ll need to keep the soft passages Soft (ready for the huge dynamics), provide your audio system with a Clean higher-powered, high current amp (one typically that doubles it’s power rating into a 4-ohm load), or install higher-efficiency speakers into your audio system!!!
Hope this helps, Ted
If you’re happy with the volume range previously, that’s a great start.
Yes. You want the inputs connected to the pre to avoid “open circuit” noise but you don’t want the pre to be adding any noise of its own. Then sit at the listening position and check for audible hiss. If you can hear any, your amp/speaker/room combination needs changing.
I would turn off the amp before turning on the pre, but yes. Same idea as the previous step except now you’re checking that your pre isn’t too noisy for the rest of the system. With no music playing, raise the volume and see if any noise starts to come through. Ideally there should be none at all, but it might be OK if you get a little bit towards the top of the volume range.
Yep. The proof of the pudding is in the eating. Enjoy!