Low powered amp and high sensitivity speakers

stereoman

Well-known member
Mar 22, 2016
146
14
10,595
Visit site
Hello,

how does it look like when you power high sensivity speakers ( let's say over 92 dB ) with a power amp 20W. I mean how loud can you go ? I heard that high sensivity speakers are generally very suitable for low powered ( valve etc. ) amps but also heard that louder listening can strain the drivers ? How much true is that ?
 

CnoEvil

New member
Aug 21, 2009
556
13
0
Visit site
There are 2 types of low powered Amps, and the same with speakers.

1. A good Solid State, Class A amp will usually have around 20-30W into 8 Ohms...but double that into 4....and nearly double that again into 2 (if you're lucky).

2. A low powered Valve Amp will output the same wattage, but use different taps for a lower impedance.

A. There are high sensitivity speakers, that have plummeting impedance (say down to 3 Ohms)....so these are more suitable with the SS amp that thrives off a difficult load.

B. The second type of high sensitivity speaker presents a much more benign impedance to the amp (eg. Audio Note), and so is more suitable for Valve Amps.
 
stereoman said:
Hello,

how does it look like when you power high sensivity speakers ( let's say over 92 dB ) with a power amp 20W. I mean how loud can you go ? I heard that high sensivity speakers are generally very suitable for low powered ( valve etc. ) amps but also heard that louder listening can strain the drivers ? How much true is that ?

Most speakers are designed to operate, without damage, at well above comfortable listening volumes.

Most low powered amps, be they valve or otherwise, require pairing with efficient or very efficient speakers to adequately fill good sized rooms.

I naturally assumed that anyone who wants to listen at disco-like levels would not be the type to go out and purchase a low powered amp in the first place.

To be serious I own a 25 watt amp and some 89dB speakers and they go way louder than I wish to listen without getting overworked.
 
gasolin said:

Whatever

You are not going to get loud from a low powered amplifier unless you have a realistically efficient pair of speakers attached, no matter what they happen to dip to, so do your homework and you'll be a happy chappy.

Ignore all input from nay-sayers, it can be done with quite pleasing results.
 

stereoman

Well-known member
Mar 22, 2016
146
14
10,595
Visit site
Al ears said:
stereoman said:
Hello,

how does it look like when you power high sensivity speakers ( let's say over 92 dB ) with a power amp 20W. I mean how loud can you go ? I heard that high sensivity speakers are generally very suitable for low powered ( valve etc. ) amps but also heard that louder listening can strain the drivers ? How much true is that ?

Most speakers are designed to operate, without damage, at well above comfortable listening volumes.

Most low powered amps, be they valve or otherwise, require pairing with efficient or very efficient speakers to adequately fill good sized rooms.

I naturally assumed that anyone who wants to listen at disco-like levels would not be the type to go out and purchase a low powered amp in the first place.

To be serious I own a 25 watt amp and some 89dB speakers and they go way louder than I wish to listen without getting overworked.

Ok ,thanks.
 

lindsayt

New member
Apr 8, 2011
16
2
0
Visit site
For listening at home, I think that 90 db peaks are loud.

What do other people think?

Would 90 db peaks be loud for you? Or would that be a bit on the quiet side for you?
 
gasolin said:
Though I've not done the maths, I expect this is the literal answer to your question, stereoman - how loud does it go? You can look up the formula!

As Lindsay implies, this is far louder than you will typically need, though as ever with hifi, the ability to cope with instantaneous peaks - like bass drum or cymbal crashes - require a bit of headroom to ensure it doesn't sound clipped, distorted or compressed.
 

muljao

Well-known member
Jul 18, 2016
334
91
10,970
Visit site
AFAIK the wattage from an amp is rated also on a logarithemic scale. I am open to correctio here, but all other things being equal, a 100 watt amp is twice as powerful as a 10 watt amp. The difference between a 25 watt amp and say a 40 watt amp isn't as much as the numbers suggest

This is my undersatanding (so if I am wrong don't blast me off the forum :) )
 

Infiniteloop

Well-known member
Jul 23, 2010
51
6
18,545
Visit site
muljao said:
AFAIK the wattage from an amp is rated also on a logarithemic scale. I am open to correctio here, but all other things being equal, a 100 watt amp is twice as powerful as a 10 watt amp. The difference between a 25 watt amp and say a 40 watt amp isn't as much as the numbers suggest

This is my undersatanding (so if I am wrong don't blast me off the forum :) )

Most Amps at reasonable sound levels are only delivering a few watts.

My 24 watt SET Valve Amp can easily produce party levels of sound without breaking a sweat into 86dB Sonus Fabers.

It's the first few watts and how easy the speakers are to drive that counts.
 

Infiniteloop

Well-known member
Jul 23, 2010
51
6
18,545
Visit site
lindsayt said:
For listening at home, I think that 90 db peaks are loud.

What do other people think?

Would 90 db peaks be loud for you? Or would that be a bit on the quiet side for you?

Agreed.

I have an App on my iPhone (SPL Meter) that I find useful to see just how loud an anvironment is.

90 is plenty.
 

gasolin

Well-known member
Al ears said:
gasolin said:

Whatever

You are not going to get loud from a low powered amplifier unless you have a realistically efficient pair of speakers attached, no matter what they happen to dip to, so do your homework and you'll be a happy chappy.

Ignore all input from nay-sayers, it can be done with quite pleasing results.

20 watt and 92db = 105 db 20watt is 13db i got it 1 db wrong but hey mabye dynamic peak power is 25watt, then it's 106db
 

davedotco

New member
Apr 24, 2013
20
1
0
Visit site
muljao said:
AFAIK the wattage from an amp is rated also on a logarithemic scale. I am open to correctio here, but all other things being equal, a 100 watt amp is twice as powerful as a 10 watt amp. The difference between a 25 watt amp and say a 40 watt amp isn't as much as the numbers suggest

This is my undersatanding (so if I am wrong don't blast me off the forum :) )

Though your terminology is a little loose.

A 100watt amplifier is ten times as powerful as a 10 watt amplifier electrically, but in an audio application, through a speaker, this only produces twice the measured spl, or in logarithmic terms +10dB. This is simple scientific fact and is not in dispute.

Whether a sound that measures twice the spl sounds twice as loud is a different matter as loudness is an entirely subjective evaluation and different from person to person.

Similarly, louspeaker sensitivity obeys pretty much the same rules, a speaker that has a sensitivity 10dB higher than another loudspeaker will deliver twice the measured spl for the same power in. Up the power by 10 times, ie 10dB and you will get the same level as the more sensitive speakers.

Simple really.
 

gasolin

Well-known member
davedotco said:
muljao said:
AFAIK the wattage from an amp is rated also on a logarithemic scale. I am open to correctio here, but all other things being equal, a 100 watt amp is twice as powerful as a 10 watt amp. The difference between a 25 watt amp and say a 40 watt amp isn't as much as the numbers suggest

This is my undersatanding (so if I am wrong don't blast me off the forum :) )

Though your terminology is a little loose.

A 100watt amplifier is ten times as powerful as a 10 watt amplifier electrically, but in an audio application, through a speaker, this only produces twice the measured spl, or in logarithmic terms +10dB. This is simple scientific fact and is not in dispute.

Whether a sound that measures twice the spl sounds twice as loud is a different matter as loudness is an entirely subjective evaluation and different from person to person.

Similarly, louspeaker sensitivity obeys pretty much the same rules, a speaker that has a sensitivity 10dB higher than another loudspeaker will deliver twice the measured spl for the same power in. Up the power by 10 times, ie 10dB and you will get the same level as the more sensitive speakers.

Simple really.

it's just that with normal people (not those who work with music and hear music different the us normal people) we find an increase og decress of 10 db as if the sound is twice as loud or lower
 

davedotco

New member
Apr 24, 2013
20
1
0
Visit site
The point is 'loudness' is subjective and varies from person to person.

For example, were you to play a piece of music and increase the measured spl 1 dB at a time, most people will say that 'twice' as loud is about 8 - 10dB up on the original, but some will be ouside these 'norms' people vary, it is just the way they are. No right or wrong here, just a subjective evaluation.
 

Electro

Well-known member
Mar 30, 2011
192
3
18,545
Visit site
lindsayt said:
For listening at home, I think that 90 db peaks are loud.

What do other people think?

Would 90 db peaks be loud for you? Or would that be a bit on the quiet side for you?

I would say 90db peaks at the listening position is fairly loud, I do listen at up to 100 db peaks sometimes when playing music with a high DR number when I am on my own.

It is quite amazing how quickly you get used to these high spl's and get the urge to turn it up more, it is also very exiting to listen at these levels it sounds like live music .

I often measure live music spl's , most small to meduim venues have peaks between 90 and 105db at the seat I am in .
 

gasolin

Well-known member
50 watt for most people is enought, small rooms about 86 db is okay, 90db in a big room

Not close to max spl with my 86db speakers,my turntable and my marantz pm8005 with the volume knob at 12 o'clock (the police), it's loud and sounds good, even when theres no distortion from my amp and therefore my amp is not close to max power,watt
 

davedotco

New member
Apr 24, 2013
20
1
0
Visit site
Electro said:
lindsayt said:
For listening at home, I think that 90 db peaks are loud.

What do other people think?

Would 90 db peaks be loud for you? Or would that be a bit on the quiet side for you?

I would say 90db peaks at the listening position is fairly loud, I do listen at up to 100 db peaks sometimes when playing music with a high DR number when I am on my own.

It is quite amazing how quickly you get used to these high spl's and get the urge to turn it up more, it is also very exiting to listen at these levels it sounds like live music .

I often measure live music spl's , most small to meduim venues have peaks between 90 and 105db at the seat I am in .

This is pivotal to the discussion and one that a lot of people fail to get a grip of.

Good recordings with a high dynamic range will, by definition require the system to have a high peak power output.

Some good acoustic or classical recordings can have peaks that are 20, even 30dB above the average level, some pop and rock recordings can get close to thiis too.

For the example given, ie 50 watts into speakers of 86db, this is what can happen.

Such an amplifier will be capable of peaks of around 70 watts, this produces into such speakers peak levels of around 104dB.

Now these are near instantaneous peaks, the average power will be 20 - 30dB less than than this, so between 74 and 84dB. Our perception of volume relates to average levels, so whilst still pretty loud, this is not earbending.

And this assumes a very capable amplifier, one that can sustain this sort of power into the complex load of a loudspeaker, some can not, and a 'perfect' loudspeaker that does not suffer from compression effects of any kind, a very rare beast. So in reality the average maximum power will be even lower than the 74 - 84dB mentioned above.

Should you use speakers with a lower sensitivity, prefer a touch of bass boost or want to play at party levels on occasion, the 50 watts available will run out of power pretty quickly.
 

NJB

New member
Nov 28, 2008
75
0
0
Visit site
I have always had relatively low power amplifiers, and think that they perform well if you like your music at modest volumes. It never seems, or sounds, quite right when an amplifier is barely off the bottom stop. However, if you have the volume control over 75% of its range then I would worry about the higher risk of clipping and associated speaker damage.
 

TRENDING THREADS

Latest posts