Please help choosing amplifiers: Acesonic, RSQ, or BMB?

Bigdog · Post by **Bigdog** » Sat Dec 19, 2009 6:38 am

http://www.igoepahire.co.uk/blog/2008/06/06/

I didn't write this article and you can Google the question yourself. This just happened to be the first article I picked.

Can underpowering a speaker cause damage? (copy and paste to the google bar to save typing)

An amplifer that is the same wattage as the speaker isn't a totally bad thing. If it has a little more power than the speakers it's called head room. A 300 watt speaker can probably take many more watts in a peak situation. Not constantly, peak. My Yamaha speakers are 500 watts, 1000 peak. Big difference. That's the head room and an amplifer should have enough wattage to provide the extra needed power at certain times. Music volumes fluctuate from whispers to roars. The amp and speakers need to be able to withstand the roars. Amps should be more power than the rated wattage of the speaker. Not the peak but the running power. If I run a 1000 watt per side amplifer it will blow the speakers if the volume knobs are turned up all the way. You could probably run that amp at 2-3 and not ever blow the speakers.

Speaker coils heating up can most definately cause the speaker to blow. There is a minute air gap between the coil and the housing of a few thousands of and inch. The heat swelled copper wiring can short out against the other side causing a burn mark and possibly causing the coil to stop moving and become welded to the other metal thereby blowing the speaker. When you see the cone moving back and forth that's the coil moving as it should producing the sound. If the coil doesn't move no sound, no speaker.

Please don't take my word for anything ....do your own search and see who is correct.

vuanh79 · Post by **vuanh79** » Tue Dec 22, 2009 10:46 am

Wow, thanks for everyone input, all these infos are very helpful.

I have bought the Acesonic Amp and the DBX 266.

DanG2006 asks:
The acesonic matches your speakers completely although I would consider new speakers. Both the dbx-266 and the dbx-166 are good compressors.
Are you happy with your uhf-5800.

The UHF-5800 microphone system is OK, I have it 3 years and the microphones still work fine.

I still have one question about how to connect all the equipment together. Is this right (below)?

Microphones connect (using 1/4mm cable) to the compressor. Then from compressor using the 1/4mm cable connect to Amplifier???

Please let me know, I'm really clueless.

One extra thing, is the EQ neccessary?

Thanks you guys.

mnementh · Post by **mnementh** » Tue Dec 22, 2009 11:22 am

Bigdog wrote:http://www.igoepahire.co.uk/blog/2008/06/06/

I didn't write this article and you can Google the question yourself. This just happened to be the first article I picked.

Can underpowering a speaker cause damage? (copy and paste to the google bar to save typing)

I've actually had a very good look at this AND the article you quote, that I have to say I'm not over impressed with.

The main failure mode in loudspeaker is generally accepted to be over power, causing excessive heat in the voice coil adhesive, NOT expansion of the Copper wire.

Please remember that "conventional" speakers struggle to be more than 5% efficient and that the other 95% is lost as heat in the voice coil, 200 watts in = 10 watts out + 190 watts heat. Chucking extra watts at the speaker is a guarranteed recipe for disaster.

An amplifer that is the same wattage as the speaker isn't a totally bad thing. If it has a little more power than the speakers it's called head room. A 300 watt speaker can probably take many more watts in a peak situation. Not constantly, peak. My Yamaha speakers are 500 watts, 1000 peak. Big difference. That's the head room and an amplifer should have enough wattage to provide the extra needed power at certain times. Music volumes fluctuate from whispers to roars. The amp and speakers need to be able to withstand the roars. Amps should be more power than the rated wattage of the speaker. Not the peak but the running power. If I run a 1000 watt per side amplifer it will blow the speakers if the volume knobs are turned up all the way. You could probably run that amp at 2-3 and not ever blow the speakers.

Again, without stating the definition of "Watts", then you might be right or wrong.

Watts are usually defined as Watts(RMS), which is, of course completely wrong as there no such thing as an RMS value for power.

The correct definition is watts (Average).

However, to go along with convention, if your Yamaha speakers are rated at 500W (RMS) and can handle that power indefinitely, then their peak continuous rating is 707W (peak). Anything above that for more than a very few seconds will destroy the voice coil.

Speaker coils heating up can most definately cause the speaker to blow. There is a minute air gap between the coil and the housing of a few thousands of and inch. The heat swelled copper wiring can short out against the other side causing a burn mark and possibly causing the coil to stop moving and become welded to the other metal thereby blowing the speaker. When you see the cone moving back and forth that's the coil moving as it should producing the sound. If the coil doesn't move no sound, no speaker.

The air gap between the voice coil and the magnet is, indeed, very small but I doubt is less that 15 to 20 thousands of an inch, even in the very best speakers.

At this kind of gap, Copper wire wouldn't expand enough to bind in the gap, even up to almost 600 deg. F.

http://www.engineeringtoolbox.com/therm ... d_859.html

Given the figures on the site above, at 600 deg. F. Copper would only expand about 5.6 thousands of an inch.

Heat damage to voice couils is almost always due to adhesive failure, resulting in mechanical distortion of the coil and thus binding in the field gap.

Please don't take my word for anything ....do your own search and see who is correct.

Here are a couple of URLs for your perusal;

http://acapella.harmony-central.com/sho ... p=29600149

http://acapella.harmony-central.com/sho ... ?t=1796660

http://books.google.co.uk/books?id=Twu0 ... es&f=false

Sandy

Moonrider · Post by **Moonrider** » Tue Dec 22, 2009 1:57 pm

Mnementh, you and Bigdog are both right. Now go get a nice cuppa klah and pay attention to what the other one is telling you.

Oh - couple more links of good reading

http://www.prosoundweb.com/article/danger_low_power/
http://www.prosoundweb.com/article/distortion_truths/
http://www.prosoundweb.com/article/clipping/
http://www.prosoundweb.com/article/how_ ... udspeaker/

Bigdog · Post by **Bigdog** » Tue Dec 22, 2009 4:39 pm

It all boils down to too much heat. Now whatever causes too much heat be it too little power or too much power, something will die. It kills computers and all other electronic equipment.

The back plate on my Yamahs speakers says 500W Program 1000W Max

500 watts all day long with slight variations above and below.

1000 watts and you're in the danger zone.

500 watt rating means you should be feeding 500 watts

This is a snipit from the link below.

1) Wattage and Power Handling -- As stated earlier, power handling tells you how much power in Watts the speakers can take without damage. Amplifiers and receivers are made to boost the original signal coming from your TV or audio source. It is important to make sure that you are pairing an amplifier or receiver with speakers that are robust enough to handle their output. Remember that the RMS, or continuous, wattage is the true specification for what a speaker can handle for long periods of time. Peak, or maximum, wattage is for brief, loud stabs of music or sound effects.

However, there are several advantages to owning an amplifier that provides more power than your speakers are rated for. As long as you keep the gain (or volume) on the amplifier low, you won't damage your speakers, your amplifier will last longer and the sound will be cleaner. Surprisingly, what usually "blows", or damages, a loudspeaker is using an underpowered amplifier with its gain cranked up to maximum. This is much like keeping the gas pedal slammed all the way down in your car. When the incoming signal from your audio source is particularly loud, it will overdrive the amplifier. This causes the amp to "clip" or distort, and that sound is passed to your speakers. Not only does this cause the amplifier to overheat and wear out more quickly, but the loud-level high harmonics in the distortion can destroy the speaker.

http://www.amazon.com/gp/feature.html?i ... 1000240601

mnementh · Post by **mnementh** » Wed Dec 23, 2009 5:34 am

Moonrider wrote:Mnementh, you and Bigdog are both right. Now go get a nice cuppa klah and pay attention to what the other one is telling you.

Terry Pratchett fan, by any chance????

DanG2006 · Post by **DanG2006** » Wed Dec 23, 2009 8:31 am

Yeah but I have seen different ratings on different amplifiers. One lists program while another lists RMS, while still another lists peak. How do you know which one is right for your speakers. An amplifier, for example, could have an RMS value of 250 watts, as does your speakers, yet have a peak of 1000 watts, while your speakers max out at 500. The above example is per side. You're gonna blow those speakers if I am correct about it. I am also in the market for a new amplifier and am looking to match my speakers with the right amplifier.

Moonrider · Post by **Moonrider** » Wed Dec 23, 2009 2:25 pm

mnementh wrote:
Moonrider wrote:Mnementh, you and Bigdog are both right. Now go get a nice cuppa klah and pay attention to what the other one is telling you.
Terry Pratchett fan, by any chance????

Anne McCaffrey

http://en.wikipedia.org/wiki/Mnementh

DanG2006 · Post by **DanG2006** » Wed Dec 23, 2009 3:00 pm

DanG2006 wrote:Yeah but I have seen different ratings on different amplifiers. One lists program while another lists RMS, while still another lists peak. How do you know which one is right for your speakers. An amplifier, for example, could have an RMS value of 250 watts, as does your speakers, yet have a peak of 1000 watts, while your speakers max out at 500. The above example is per side. You're gonna blow those speakers if I am correct about it. I am also in the market for a new amplifier and am looking to match my speakers with the right amplifier.

I only found one that said anything about max power and RMS.

mnementh · Post by **mnementh** » Wed Dec 23, 2009 5:27 pm

Moonrider wrote:
mnementh wrote:
Moonrider wrote:Mnementh, you and Bigdog are both right. Now go get a nice cuppa klah and pay attention to what the other one is telling you.
Terry Pratchett fan, by any chance????
Anne McCaffrey

http://en.wikipedia.org/wiki/Mnementh

Well spotted.

You're the first on any forum I'm on to make the association.

Read Dragonflight and the rest of the Pern series MANY years ago.

Also, if you like coincidence, I was born at the hour of the Dragon, in the month of the Dragon and in the year of the Dragon.

Spooky! No?

Sandy