High power D class amp for low power speakers

[Canyonhk]

Hi, All,

Just want to ask a question. I am interested in D class amp and most of them have very high power reading such as 400W for 9040 monoblock. I have a B&W 804 with suggest amp power between 50-200w. Is it very easy to be overpowered and "burn" my speakers? I am using RME directly to power amp (without pre amp).

Thanks in advance!

Kenny

 

[staticV3]

The RME has a function to set a maximum output voltage that cannot be exceeded.

Set it to a low voltage so that the 9040 cannot output more than 50W or w/e and burning the B&W will be impossible.

This spreadsheet may help: https://www.audiosciencereview.com/...o-v3-mono-amplifier-review.53474/post-1933409

 

[DanielT]

Is it very easy to be overpowered and "burn" my speakers?

Normally no problems, as long as you don't play at really high/max volume for a long time.With an amp with more power than the speaker manufacturer states the speakers can handle: Do not turn the volume up too high on the amplifier.

Also. You can choose a class D amp with a little less power, but with good performance like 3e Audio, for example:

3e audio A7/A7 Mono Amplifier Review

This is a review and detailed measurements of the A7 / "A7 Mono" stereo power amplifier with balanced inputs. It was sent to me by the company. I have no idea what it costs in US. Audiophonics lists it for 379,00 €tax incl. While the A7 may look like its competitors, it has a heft to it that I...

www.audiosciencereview.com

Or if you don't need that much power this one:

3e Audio A5 Stereo Amplifier Review

This is a review and detailed measurements of the 3e Audio A5 Stereo class D amplifier. It was sent to me by the company and costs US $229.99. Despite its simplicity, the A5 has very well thought out features. Clipping indicators are provided for each channel. And selection of inputs is made...

www.audiosciencereview.com

 

[DanielT]

The RME has a function to set a maximum output voltage that cannot be exceeded.

Set it to a low voltage so that the 9040 cannot output more than 50W or w/e and burning the B&W will be impossible.

This spreadsheet may help: https://www.audiosciencereview.com/...o-v3-mono-amplifier-review.53474/post-1933409

Smart solution.

 

[boXem]

From my experience, the first thing speaker manufacturers look in case of warranty claim is the amplification power. Too much power = not their fault if the driver was blown.
A Purifi 1ET6525SA is as excellent as a 1ET9040BA and stays within the limits given for your speakers.

 

[Mark the Monk]

Its easier to blow speakers with amps that are underpowered they will clip you may not hear it and they will blow at some time but when you have more power than needed you will hear a definite overload distortion before they blow.

I would say use with caution IE dont go to excessive levels, If you do like your music very loud then obviously consider less powerful amp. If you listen at relative normal listening levels you will be fine.

 

[0bs3rv3r]

Do not exceed your speakers' capability. You cannot guarantee to only feed it lower signals and listen at safe levels. If you connect a big powerful amplifier, one day a spurious signal will reach the amplifier, maybe just from a bad connection, or some failure upstream, and it will blow those speakers apart

 

[Head_Unit]

B&W 804 with suggest amp power between 50-200w

That's a Marketing Department suggestion, not a real thing. Speaker power handling I'll say as a loudspeaker engineer is way too complex to distill into one number or a range of numbers. It has much more to do with the type of music and then how loud and how distorted the playback is. As @Mark the Monk notes more power is better IF you are not cranking it "to 11" into distortion. In your case if your amp has a ton of power, set the gains so 0 dB on a digital source would hit the 400 watts of the amp. That means only dynamic peaks would hit 400 watts, and I'd be really surprised if anything burned.

 

[tineared]

If you don't hear the distortion long before you blow a driver, then you are too drunk

 

[Mark the Monk]

If you don't hear the distortion long before you blow a driver, then you are too drunk

Ive met a couple of guys who liked their music loud and where using low ish powered amps they had blown tweeters and didn't even hear the clipping before they blew. 30 watt amps into 100 watt speaker will not work well if you like loud music, Those amps are going to be clipping very early.

My speakers are rated 30 watt to 150 watt I power them with 300 watts per channel i've had these speaker since late 90s my volume never goes above a quarter on the vol control and thats getting reasonably loud, but the power in reserve is often used for dynamics and transients.

Split second transients of well over the rated speakers loading are not long enough to do any damage, Its when that power is sustained over the rated levels you will hear speaker bottom out first, Amp clipping being the more dangerous is harder to hear and pushing low powered amps high will clip and destroy the tweeters.