Power Matching - Speakers and Amplifier

Muthusami S

Member
Joined
Mar 18, 2008
Messages
281
Points
18
Location
Chennai
Dear friends,

A query about matching the amplifier power and speaker power. I am using 100Wx2 RMS stereo integrated amplifier. This is

connected to floorstanders of 150Wx2 RMS output. While purchasing the floorstanders from Mr. Murugesan (late), Audiocraft, he told me that it is always suggested to use higher powered speakers than the amplifier power because it is safe for the speakers when the volume is raised accidentally to the maximum. Contrary to this, somebody told me that the speaker power can be less than 20% of the amplifier power so that the maximum power of the speakers are utilized. Are these two methods technically correct? Or using the same powered speakers and amplifier (e.g. 100W speakers+100W amplifier) will produce good results?

Please share your views.

Regards,
Muthusami. S
 
Before forum expert/s pitch in , I would like to add something. Driving a high power capacity speaker with a very low powered amp is more dangarous than a high power amp driving slightly less power capacity speaker.

It is the low power amp when maxed out , clips and causes maximum damage to speakers.
 
Last edited:
You'll blow your ear drums before a speaker reaches its excursion limits due to amplifier current. More power is never an issue. Its the lack of it that is the problem since the amp can clip causing blown tweeters in a speaker.

However to confuse you even more, the output sound quality of an amp has nothing to do with its power capabilities. A 10 watt amp can have as much drive as a 100 watter at times and can sound better too.
 
Dear friends,

A query about matching the amplifier power and speaker power. I am using 100Wx2 RMS stereo integrated amplifier. This is

connected to floorstanders of 150Wx2 RMS output. While purchasing the floorstanders from Mr. Murugesan (late), Audiocraft, he told me that it is always suggested to use higher powered speakers than the amplifier power because it is safe for the speakers when the volume is raised accidentally to the maximum. Contrary to this, somebody told me that the speaker power can be less than 20% of the amplifier power so that the maximum power of the speakers are utilized. Are these two methods technically correct? Or using the same powered speakers and amplifier (e.g. 100W speakers+100W amplifier) will produce good results?

Please share your views.

Regards,
Muthusami. S

Dear Muthusami,
A speaker just does not blow. As mentioned by Roc & Suhas its much more likely to blow a speaker with a small amp driven into hard clipping as against a bigger amp. With a larger amplifier u will simply get better sound and will extract every last ounce from your speaker and there will be a sense of effortlessness as the load(the speaker) is easily handled by the amplifier.

A friend of mine is driving speakers rated at 150w @ 8 ohms with 600 w monoblocs and they sound sublime. U will probably leave the room with the sound pressure before the speaker blows. I personally am driving a speaker rated at 120W with a 300 W amp and the sound is definately more dynamic than when i drove them with a similar bryston which was 150W.

But if some fool were to turn the amp to the maximum am sure there will be some damage but IMO that would occur irrespective of amp size. Actually once again your ears are the deciding factor as u will hear the speaker STRAINING to reproduce accurately as u increase the volume. Lastly most reputed speaker makers will rate their speakers conservatively as opposed to say a sony Midi system which will claim to dish out 4000/5000 watts PMPO!!!!

Regards
 
Last edited:
Hi,

Think of speaker's sensitivity.If sensitiviy is low (85db), you need 100 to
150w amp to drive.
If 90 db then 30 to 50 w amp (for same sized speaker)is ok.

If high wat speakers combined with low wat amp ,speaker will ask for
more current from amp to drive smoothly (duo to lower sesitivity)
Result-Distortion,damaging your amp.

So go with low wat speaker with high wat amp.
Even whathifi mags suggest Tannoy 70 wat spk with 140w Onkyo avr.

Hope you got.
 
Dear Sri Muthu,
pl refer to the spec of any company make HTiB and u will get ur answer. Always the amp carries more power than the max rms driver can handle and as a thumb rule they can be in 2/3rd range of amp rms. U need only to take care not to cross the limit of ur amp when the driver becomes no more sweeter for ur ears. The chance of getting ur amp heating up and finally just blowup due to higher current is more when u connect the drivers of higher rms than the amp. For ur drivers with 150w rms each u can have something around 200w rms per channel amp at the impd. rating of ur drivers. Hope this will clear ur doubt. In case u have low impd. drivers as compared to the rated amp. then suitable correction factor can be taken, if ur amp is able to handle low impd. drivers, may be just 4 or 2 ohms.
regards
 
Dear Sri Muthu,
pl refer to the spec of any company make HTiB and u will get ur answer. Always the amp carries more power than the max rms driver can handle and as a thumb rule they can be in 2/3rd range of amp rms. U need only to take care not to cross the limit of ur amp when the driver becomes no more sweeter for ur ears. The chance of getting ur amp heating up and finally just blowup due to higher current is more when u connect the drivers of higher rms than the amp. For ur drivers with 150w rms each u can have something around 200w rms per channel amp at the impd. rating of ur drivers. Hope this will clear ur doubt. In case u have low impd. drivers as compared to the rated amp. then suitable correction factor can be taken, if ur amp is able to handle low impd. drivers, may be just 4 or 2 ohms.
regards

Hi,
Actually i have no idea of HTIB but am surprised to learn that the built in amplifier delivers more than the speakers power rating.
Amps normally heat up when driven and more when driven hard. Depends on the type of amp. Low Speaker impedance, poor ventilation etc are more likely for an amp to go into a thermal shutdown than driving a speaker with a larger power handling IMO. Some larger amps heat to a point where you cant touch the heat sinks and still play ok for years.
Regards
 
Hi,

I thank you all very much for your explanations. It is very useful to me. So is it better to upgrade my amplifier from 100W to 200W because the woofers are 150W RMS. Please advise.

Regards,
Muthusami. S
 
Again... buy an amp that sounds better. Not an amp that has higher specs. I just got a used Class A Musical Fidelity A1 integrated amp for my bedroom speakers. This dimunitive amp is rated at a very meagre 20Wx2. However you should see the way it moves speakers. Both my speakers - The Usher Be-718 and Jamo E700 are very hard to drive as both have very low sensitivity and they are not an easy load for an amp. However you'd be amazed at what this little amp can do. Just 20W but I've seen weaker 100 watters than this.
 
Again... buy an amp that sounds better. Not an amp that has higher specs. I just got a used Class A Musical Fidelity A1 integrated amp for my bedroom speakers. This dimunitive amp is rated at a very meagre 20Wx2. However you should see the way it moves speakers. Both my speakers - The Usher Be-718 and Jamo E700 are very hard to drive as both have very low sensitivity and they are not an easy load for an amp. However you'd be amazed at what this little amp can do. Just 20W but I've seen weaker 100 watters than this.

Thank you very much.

Regards,
Muthusami. S
 
Hi,

I thank you all very much for your explanations. It is very useful to me. So is it better to upgrade my amplifier from 100W to 200W because the woofers are 150W RMS. Please advise.

Regards,
Muthusami. S

Firstly Muthusami why do u want to upgrade? Is it because u are now convinced that a bigger amp will be better or because u feel there is something lacking in the set up. If its the latter then sure explore different amps. Please do not take any hasty decisions and part with your money. I have never heard a similar set up to yours so cant really comment on the pros or the cons. As ROC said buy the best sounding amp/combo as finally its about enjoying the music that the goal of all this is.

Roc i too heard the new MF A1 last week and it was a sweet sounding amp. I believe its a 36WPC pure class A. I also heard the new YBA cdp + integrated which was also very smooth sounding and beautifully built.
Regards
 
Last edited:
Dinyaar has made a very good point. Maybe your amp is a perfect match for your Craftel speakers. Maybe later on you can think of upgrading the whole setup i.e speaker and amp
 
Firstly Muthusami why do u want to upgrade? Is it because u are now convinced that a bigger amp will be better or because u feel there is something lacking in the set up. If its the latter then sure explore different amps. Please do not take any hasty decisions and part with your money. I have never heard a similar set up to yours so cant really comment on the pros or the cons. As ROC said buy the best sounding amp/combo as finally its about enjoying the music that the goal of all this is.

Roc i too heard the new MF A1 last week and it was a sweet sounding amp. I believe its a 36WPC pure class A. I also heard the new YBA cdp + integrated which was also very smooth sounding and beautifully built.
Regards

Dinyaar,

I am satisfied with the existing setup but afraid of any damage to the amplifier because of high powered speakers than the amplifier's. That's why asked suggestions from the forum. Thanks.

Regards,
Muthusami. S
 
Rikhav,

Thank you very much for your opinion.

Regards,
Muthusami. S

Dinyaar has made a very good point. Maybe your amp is a perfect match for your Craftel speakers. Maybe later on you can think of upgrading the whole setup i.e speaker and amp
 
Roc i too heard the new MF A1 last week and it was a sweet sounding amp. I believe its a 36WPC pure class A. I also heard the new YBA cdp + integrated which was also very smooth sounding and beautifully built.
Regards

I had heard the A100 before with a pair of klipsches and it sounded wonderful. Then Ramesh(hifipal4all) the other day mentioned he has an original A1 for sale. I didn't even think twice. At just under 10 grand that I paid, this is the biggest hifi steal ever. This one is 20Wx2 and the first 8W or so is pure class A. Beyond that is class AB. However there's very little requirement for power more than 8W when listening atleast for my tastes. The amp is definitely not the most neutral out there but the way it reaches out and brings the body and soul of the music is just incredible. This is hands down the most musical and sweet sounding integrated I've ever heard. Infact when Ramesh heard it at my place, he jokingly said that he probably asked too little money from me for it :).
 
Last edited:
Hi ROC,
Glad to hear of the HIFI steal!! If this is the same J. Ramesh Babu from bglore give him my regards. He spent a day with me in Bbay and is a lovely bloke. He flew down just to buy/carry back my B&W 603 and had quite an adventure !!
Regards
 
Hi ROC,
Glad to hear of the HIFI steal!! If this is the same J. Ramesh Babu from bglore give him my regards. He spent a day with me in Bbay and is a lovely bloke. He flew down just to buy/carry back my B&W 603 and had quite an adventure !!
Regards

Yup he's the same person :). Infact he told me a lot about you and he still has your pair of speakers.
 
I had heard the A100 before with a pair of klipsches and it sounded wonderful. Then Ramesh(hifipal4all) the other day mentioned he has an original A1 for sale. I didn't even think twice. At just under 10 grand that I paid, this is the biggest hifi steal ever. This one is 20Wx2 and the first 8W or so is pure class A. Beyond that is class AB. However there's very little requirement for power more than 8W when listening atleast for my tastes. The amp is definitely not the most neutral out there but the way it reaches out and brings the body and soul of the music is just incredible. This is hands down the most musical and sweet sounding integrated I've ever heard. Infact when Ramesh heard it at my place, he jokingly said that he probably asked too little money from me for it :).


After reading what you write about the A1 amp I was too keen to know more about it. So i went to the offical site. Musical Fidelity has some product called as "SUPERCHARGER" which you can connect to your A1 to have as much power as you desire. So basically your A1 does not go waste if you plan to have a more powerful system
Now i undertand how does a super charger works with a car engine nut no experience with his Musical Fidelity Supercharger.
I will read the explanation given on the site but it would be great to hear the experience from someone using the SUPERCHARGER with A1
 
Yup he's the same person :). Infact he told me a lot about you and he still has your pair of speakers.

HAHAHA i hope it was all good. Actually it was an amusing day with Ramesh. He came on a sunday morning @ 7 AM when he was to come by 10 and then the cabbie dropped him far away and i rushed half asleep to fetch him. He very clinically heard the set up and loved the sound of the speakers. He had heard them earlier and said the sound was stuck in his mind. I told him i didnt like them and was hence selling. He was to take the speakers and go over to a friends house and return to bglore the next day. But his friend was holidaying somewhere when poor Ramesh called him and Ramesh got really worried as he had never come to bbay before. So we went for lunch and a city tour but all Ramesh wanted to do was to buy some remotes which i found really amusing!!!! I doubt he enjoyed his meal as he had a really worried look. Finally i took him to the railway station and tried to get his ticket preponed to enable him to take the train the same day and after some under hand dealings with the ticket office and the police( to park till we sorted the mess) we managed. We sat and had a MUMBAI SPECIAL VADA PAV meal on the platform and i saw him off.
My last train journey must be a decade ago and dear Ramesh was no expert either. I told him to call when he reached bglore the next morning but the poor chap called from the train saying the arrival time was 9.PM and not 9AM as i had indicated and that he was to spend the entire day rocking in the train!!!!!!!!!
He promised me that the speakers were for his personal use and keeps telling me every now and then that they are still there!!!!!!!!!!
Sweet chap and a funny day spent. Please give my regards to him ROC and tell him i am going to come and surprise him and CHECK if he still has the speakers!!! HAHAHA.
Regards
 
Rikhav,
Had read about the MF super chargers a while ago. If i recall correctly they are just MONO BLOCS to be used with a good preamp and the A1 being class A entirely should make a clean sounding pre. Its basically a vertically designed power amp IMO and i think outputs 550W.
Regards
 
Purchase the Audiolab 6000A Integrated Amplifier at a special offer price.
Back
Top