Changing the amp from 50W to 80W, opinion needed

I'm using a 65W amplifier with the speakers that recommend minimum 80W power. However, I don't find any problems with this combo. Moreover, I'm happy with them.

Nevertheless, as there were series 2 of amplifiers available and they had 100Wpc power. Although there's nothing wrong with my current system, I'm curious that if I change the amp to the series 2, will I gain a huge difference?

Amplifiers
Series 1: Braun Atelier A1 (65W @ 4 Ohms)
Series 2: Braun Atelier A2 (100W @ 4 Ohms)

Speakers: Braun LS200 (4 Ohms)
 
My friend suggests me similar to reply #2. He stated that the capability of speaker driving could be obtained by “sensitivity” of speaker rather than minimum recommended power. Is this true? However, I see most multi-way speakers have sensitivity in a range of 88-94 dB. So, does it imply that most speakers need similar Watts?
 
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So, what is the benefit of big amps, please, if 20-30 Watts is enough?
Hi,
It depends of your needs of SPL at listening spot: if you are located at a 'big' bistance ( let's say 4 meters) then you'll need 12db more output* from your loudspeaker than at 1meter. This equal to multiplying by 16 the power requirement: iow if 20w at 1meter you'll need 320w for same level at 4m.

Other thing to consider is headroom: underpowered amplifier ( for a given situation) will clip. Clipping is detrimental to sound quality and can destroy your tweeter.
Oversizing the amplifier will push this limitation away but you'll have to watchout for not using the whole power the amp is able to deliver ( where you run a 20watt amplifier at full power ( 0db) a 320w amp should not be run beyond -12db for same level at 1meter ( but you now have 12db headroom availlable: amp will never clip and destroy tweeters).
Seems like a waste to most amateurs. In pro circle ( studio) this kind of choice of gain staging ( it's part of your reproduction chain's gain staging) is common for good reasons.

Up to you to make choice about it and limitation this choices brings.
Food for thoughts:
https://sound-au.com/tweeters.htm

* for typical loudspeakers each time you double distance you loose 6db: eg, from one to two meters:-6db, from 2 to 4:another 6db loss, etc,etc,...
The exception to this being linearray.
 
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stv

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if 20-30 Watts is enough?
If that is enough for you then there is no point in buying a bigger amp.

double the power results in +3 dB of sound power/pressure which is just noticeable, for percieved double volume you need 10 times the power.
So you should rather consider upgrading from 60 W to 600 W if you need louder sound ;-)

you may be surprised how low the power at your usual listening volume actually is.

The main issue is: how loud do you listen? And what is the respective required power? Also what is the crest factor of your music?

there are several threads about this issue, for example:

https://www.diyaudio.com/community/...ou-really-need-for-domestic-listening.163657/

(Ok, read @krivium s post above for more details!)
 
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So, what is the benefit of big amps, please, if 20-30 Watts is enough?
Do you host parties? Bodies soak up sound, also talking drowns out the music. Do your party invitees like loud music drowning out the talking?
In a 132 m cubed room, I listen at 1/8 to 70 watts. 70 watts 0.01% of the time, 1/8 watt 50% of the time. I have 98 db 1w1m speakers. You might need 2 watts to listen to orchestral music medium soft on 84 db 1w1m speakers.
If you play loud a lot then clipping and blowing the tweeters is a risk. Too much high freq blows tweeters, and consumer speakers don't have tweeter protection. Clipping creates sharp edges, which have a lot of high frequency content. Pro PA equipment has an incandescent light bulb series the tweeter, to gently decrease the volume without creating sharp edges. Silk dome tweeters are particularly sensitive.
You can measure your listening power with an analog AC voltmeter. AC scale of an analog DVM (with a pointer). Just put the probes on the speaker terminals with alligator clip leads, if you have a screw terminal strip. Use 20 vac or 50 vac scale. Other types of terminals may require a paralleling adapter cord. These meters are typically $25-30 on ebay, amazon, alibexp. DVM (digital) lie a lot on music; their AC scales are for the wall power frequencies. The $160 RMS DVM ignore frequencies above 7000 hz, which is where the problem with clipping occurs.
My ST70 tube amp has 35 w/channel. I was not happy with the 2 w/ch amp in my Mother's RCA stereo. 2" full range speakers weren't much to brag about either. Class A tube amps are lower in power than the ST70. I did blow a tweeter once with the ST70, and I didn't do it at a party. Was a big mystery at the time. Was a $2 3" paper cone tweeter in a LWE III speaker.
 
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Many tube amps are only 2 to 5 watts. You can get them bigger, but more power is more money (a lot more money). In theory, solid state and tube watts are the same, but with SS they often play games with the power ratings so you’re getting less than you think you do. But even if power ratings are the same, the tube amp will typically sound louder because you can and will run it harder. If you clip a 2 to 5 watt solid state amp, even a little, it is painfully obvious. At the same distortion level with a tube amp the user is often blissfully unaware that it’s clipping because it’s more graceful-sounding when it does. The end result is that you play it louder (for equivalent “watts”).
 
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Stv is right:
It depend of your listening habits: crest factor of music,etc,etc,...

To summarize:
Each time you double distance to source you loose 6db (-6db),
Each time you double power of amp you gain 3db (+3db),
Headroom you need:
Level needed at listening point,
And from there power requirement will depend of dynamic range ( crest factor) of music you listen to.
Background noise of your place will play a role too: noisy environnement may require a bit more spl than quieter one... size of your room too ( the 83dbspl i talk about after is for big room, smaller require a bit less...)



About dynamic range: if you listen EDM, Metal, recent pop music,... your need of dynamic range are low ( eg Metallica's 'Death Magnetic' first release had something like 3db dynamic range...).
If you listen to well recorded Classical or Acoustic music then your dynamic range requirements are high ( difference between average (rms) level and peaks encountered can be as high as 20/24db).

So from there try to find the highest dynamic range record in your collection: it'll define your worst case scenario about power needed.
If you don't own a software able to tell you rms/peak of tracks then a look at this will help you define this dynamic range:

https://dr.loudness-war.info/

Otherwise you can proceed as we do in studios:
We define an rms level needed at listening point ( 77dbspl rms for music with 6db of headroom= 83dbspl for one loudspeaker playing).
We know we need 20db crest factor and limit in digital being 0dbfs: we play a pink noise at -20dbfs with monitor level fully open (0db, zero attenuation).
If your amplifier are correctly sized then with an splmeter on C calibration at listening point you should have 83dbspl reading...

Beware it is LOUD and you'll probably need to run your level pot circa minus 14db most of the time, closer to minus 20/24db for low dynamic range material, close to minus 6db for high dynamic range material.

Tube amps: classA triode yes 5w max is typical. If runnind compression driver with around 100db/1w/1meter it's perfectly fine to rip your head off at one meter.
With a low efficiency loudspeaker...
 
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Are the watts from tube amps and SS the same?
Yes exactly the same... but:
Output impedance of tube amps is usually higher than SS and it can change things wrt lowend behavior,
Distortion profile ( harmonic contents) and way it happen is different which can lead to different interpretation from our brain.
 
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@adason...

That's a MkII..... ay! For the VT100 you want the MkIII.

https://www.arcdb.ws/model/VT100

But, these sound better:

https://www.arcdb.ws/model/D115
https://www.arcdb.ws/model/D70

All analog.

For most people, the D70 is all the power you will ever need... except with stuff like Maggies. ( Hint I got both a D70-II and some Maggies )....

I guess it comes down to what NP said about the First Watt. Only seldom do you need the First Hundred Watts.

I guess other things like damping and ability to drive current into wicked low loads and crazy phase shifts will require an amp with some serious cojones.
 
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Yeah... I got one of them Radio Shack power meters... APM-200.

https://revintages.com/realistic-apm-200-vu-power-meter/

With sane speakers, at sane levels, the meters will seldom go above 2 watts... maybe 5 watts on peak.

But with insane speakers, like mine, 10 watts is the "normal"...

BTW, I ought to note that the next time I see a VT200 MkII, I'm gonna pound on it...
 
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I had few of those RadioShack meters, various models. Not for serious measurement, those are lazy needles ignoring peaks.
Memory scope is the only way to accurately detect music peaks.
I have old akai power amp, not in use, but it has nice green fluorescent display. Up to 70 watts. At normal listening, not even first bar goes on. Luckily there is 0.1x switch, with ten times the sensitivity, full scale 7 watts. Then i finaly see some fluorescent bars.
Its amazing how little power is required at normal listening.
For party, or PA, its totally different. No power is enough.