Understanding Amplifier power/ratings

[bluestar]

OT, but how do you like the Willsenton R8? Everyone raves about them.

FOr the price its great ! and completely objectively it also sounds quite good with a def tuby sound and is quite forward. Seems to have enough power to run any speaker I throw at it.

Haven't had a chance to do an A/B with another tube and hardly spent any time with tubes otherwise so don't have a lot to compare it too. I can't tell if the downsides when compared with modern class ab and d is something to do with these tubes specifically or tubes in general. Don't have the 'depth' of some of the more modern sound, otherwise would recommend to anyone looking to dip their toes or for a second tuby sounding system.

 

[chander]

its another thought, if an audiophile only technically needs 5 watts to get to desired db then why do people even bother with getting 200 - 500W per channel class d amps, whats the point ? when is the last time you saw a 15W class d amp but people buy 15w tubes all the time.

This is exactly where things become confusing for me too. To give you an example, I am always listening at around 60Db in my office (I learnt this today). My speakers are rated at 84Db per watt per Mt and I am within 1MT from each speaker (used in near field), and are being driven by a 50WPC Class AB integrated. Now logically and going by the maths of it, I am only using 1 W or Maybe 2 at max, but apparently I need a "more powerful" amp to get more out of my speakers. I do not get it either. As far as I understand - I am using 1W till I go completely deaf - around 84Db, what is the remaining 49W for? How are they helping? I understand most testing happens in Anechoic chambers, but even then.

I was talking to a friend as I was able to get a used Tube amp with 2W per channel from the US for a decent enough price, but a friend of mine who uses tubes said it won't drive my speakers and I need better efficiency. So I am generally lost.

Can you simplify your conclusions? i can't seem to parse out the conclusions from the writing

My conclusion seems pointless now after reading your response - so I guess ignore I do not know the watts being used by the amps to reach 87Db - so technically useless.

 

[ssf]

https://www.crownaudio.com/how-much-amplifier-power

https://www.crownaudio.com/en-US/tools/calculators#amp_power_required

From the above links, it looks to me like amp power is required to handle the peaks in music so that it does not clip. Also, typically, we don't sit one meter away from the speakers so that has to be taken into account too.

 

[chander]

https://www.crownaudio.com/how-much-amplifier-power

https://www.crownaudio.com/en-US/tools/calculators#amp_power_required

From the above links, it looks to me like amp power is required to handle the peaks in music so that it does not clip. Also, typically, we don't sit one meter away from the speakers so that has to be taken into account too.

I understand - I was wondering as whenever I speak about 2-5W tube amps almost everyone tells me not even bother with anything below 25WPC for the 84DB sensitive speakers. So was wondering.

 

[ssf]

I understand - I was wondering as whenever I speak about 2-5W tube amps almost everyone tells me not even bother with anything below 25WPC for the 84DB sensitive speakers. So was wondering.

I have no experience with 2-5 W tube amps. I have a Topping TP60 which is rated at 50 watts class D (probably at 10% THD so, must be around 20 W or so) Nice sounding amp at low volumes. But it was struggling to drive the Quad 12L2s to loud levels.

 

[bluestar]

This is exactly where things become confusing for me too. To give you an example, I am always listening at around 60Db in my office (I learnt this today). My speakers are rated at 84Db per watt per Mt and I am within 1MT from each speaker (used in near field), and are being driven by a 50WPC Class AB integrated. Now logically and going by the maths of it, I am only using 1 W or Maybe 2 at max, but apparently I need a "more powerful" amp to get more out of my speakers. I do not get it either. As far as I understand - I am using 1W till I go completely deaf - around 84Db, what is the remaining 49W for? How are they helping? I understand most testing happens in Anechoic chambers, but even then.

I was talking to a friend as I was able to get a used Tube amp with 2W per channel from the US for a decent enough price, but a friend of mine who uses tubes said it won't drive my speakers and I need better efficiency. So I am generally lost.


My conclusion seems pointless now after reading your response - so I guess ignore I do not know the watts being used by the amps to reach 87Db - so technically useless.

we are both quite confused it seems.... even our good friend pal couldn't explain it cleanly enough

He however says something very interesting - 'amps don't push power' but then confuses me when he mentions turning the volume knob...

He does however, say towards the end, that higher wattage amps do 'sound better' in general.

I think my next purchase is going to be best measuring; highest available wattage per channel amp/monos for under 2L and then run around the city trying them out with tough and expensive speakers... lets see... maybe they will blow away the 12L devialet amps.... any recommendations ? I"m thinking emotiva or nord acoustics?

 

[chander]

Interesting Nelson Pass article

https://www.passlabs.com/technical_article/single-ended-class-a/

www.hifivision.com

some interesting info there! A bit too technical - but interesting none the less - gives the direction to understand the basics to apply to the question here. Lots of reading to do!

 

[sandeepmohan]

any recommendations ? I"m thinking emotiva or nord acoustics?

You can't go wrong with the former. They are known for their power amplifiers more than anything else that they sell. I have not heard Nord acoustics so won't comment.
Amplifiers are built different by each manufacturer.
I won't fall for the trap of higher wattage is always better. Its about the quality of power that is put out by the amplifier.
Its also about careful pairing of the loudspeaker.
A loudspeaker that is sensitive may do just fine with a 25 watt amplifier. One that isn't will need bucket loads of power and huge caps to keep the power flowing.
I guess what the author was implying was that if you have more power, its more headroom to drive difficult speaker loads.
Measuring is fine. Personally; I won't decide on equipment based solely on measurement. Your ears can also decide that.
You might want to look at Mytek Brooklyn. 300 watts @ 4ohms from an amplifier the size of a lunch box! That is not cheap watts. Its really good, clean digital power that is guaranteed to make you think you are listening to a traditional class AB amplifier.

 

[ktks1]

If you're considering emotiva, their ODM seems to be providing amps at a decent price point.
I came across this thread y'day which might help with the links: https://www.hifivision.com/threads/tonewinner-at-300-7-3-6-av-processor.85762/

Also, if you're looking for stereo only and have the budget, consider Purifi based (Nord, Apollon, Audiophonics) or GaN based (Starkrimson) as the endgame purchase. They have glowing reviews almost everywhere

 

[Kannan]

All this confusion and variables is mainly because speakers need AC voltage to function and would blow if it was fed a constant DC voltage
Also speaker is not a static load depending on the music power and the amp would need the capability to handle 80db to 103db of details (transients) is a music track at the same time (cresendos) or within extremely short span.
Amplifier power involves multitude of variables like its fluctuating ac output (that is why vaguely referred as RMS power, )the varying load of the speaker at different frequencies, speaker sensitivity, preamp output mpedance and sensitivity to name a few.
Class A is always in on state at a higher bias, so can broadly deliver instant current and can sound louder at lower watt than othe Class amps. But Class A are inefficient heat guzzlers and impractical for proaudio gear or when it comes to miniaturization.
All said and done, my ears are still Class A friendly given under the same parameters comparison. I use Class A at home and all Class D in my car.
A is 5 watt and the D 15 watt

 

[drlowmu]

The best sounding amplifiers in this world, that "I" am aware of, are all about two Watts or less, tube, Single Ended. Unfortunately, in that low powered / high quality amplifier category, 99.% of the commercially-available amps you will find - will not cut the mustard - to be considered the world's best sounding amplifiers.

Generally speaking, amplifiers, and not the speakers, are the weakest link in audio.

I believe, if you seek the best possible overall sound, you start by having the right kind of speaker.

That is a professional-use speaker ( not necessarily a commercial speaker ). It needs to have an efficiency of 101 dB / 1 Watt / 1 meter or higher. A simple speaker, not a one-way, but a two-way with a 15 inch woofer. Think Movie Theatre use speakers , vintage with ALTEC drivers, or modern-day, more costly GPA drivers. Budget no problem what so ever, ALE.

I do not mean to throw your thread off kilter, but I believe you are going about things.......... backwards.

I simply wanted to express my opinion, openly. Good luck to you. I hope you find what you are looking for. I have, after many decades, with errors made ...... while going for it.

Have fun. I have. YMMV from mine.

Respectfully,

Jeff

 

[chander]

Also speaker is not a static load depending on the music power and the amp would need the capability to handle 80db to 103db of details (transients) is a music track at the same time (cresendos) or within extremely short span.

One question here - to get a better grasp on this sentence above. You mention transients and crescendos in music and the need for high power when music demands, which I understand, but if your general listening level is low, which I have been constantly measuring under 62 Db over 15 songs, never above. In that case - my speakers being 84Db per W, am I still using more than that 1st watt (I use my speakers in near field - so within a meter)? Or am I still using more even though I never reach the 84DB? If I am not using more than that 1st W, I should technically be fine with a 2W tube amp provided I always listen below 65Db and provided I always sit within 1 Mt?

Edit : checking the app - says highest reached 71.2 Db average being 60.1Db.

This will clarify some doubts .

A simple to understand video here -

 

[Kannan]

How many watt your amp is using to generate 65db at your listening position depends on the capability of your amp to drive your speaker load of the stated 84db without distortion.
If using a preamp, then it too plays a role.
The best measure is to monitor the details in the music across the full bandwidth or the lack of it as you attenuate upwards or downwards between say 60db to the max you can tolerate at your listening position.
Though the spl (loudness) may fall, there should not be slack in the music bandwidth.

Whether 1 watt, 2 watt or 20 watt produces music at your listening level really does not matter as long as it is distortion free. Our ears anyhow cannot discern anything under 1THD.

An amp can produce clean power depnding on its design at 1 watt as well as at 100 watts.

To get twice spl at the same distance 10 times the rated power is what is needed as per theoritical equation, but that is at a fixed sinusoidal point or frequency. With music being a varying load that figure should be even higher in.practice.

I recently completed a 20 watt rated Class A amp. It needs juat a 8 o clock setting in my pre to get loud enough in my room as againt the 5 watt Class A which needs a 11 o clock setting on the pre.

In my listening distance the 5 watt makes a better bet as I get a wider range of volume to play with.

 

[chander]

Thanks a ton!

 

[ssf]

And to make thinks even more interesting, I have read that a 2 watt tube amp can go up to 20% of its power before distortion sets in. A generalization, I agree but I feel it's better to be safe than sorry when it comes to power unless one has a speaker with an efficiency of 101 dB / 1 Watt / 1 meter as @drlowmu mentions in his post.

 

[drlowmu]

And to make thinks even more interesting, I have read that a 2 watt tube amp can go up to 20% of its power before distortion sets in. A generalization, I agree but I feel it's better to be safe than sorry when it comes to power unless one has a speaker with an efficiency of 101 dB / 1 Watt / 1 meter as @drlowmu mentions in his post.

" Better safe than sorry when it comes to power " you state above. ............ But I say " there is a price to pay " for such reasoning .

The audible problem is, the best made amps over about two Watts " sound clunky " or, not quite as good as the best made amps of lower power.

Most of the time ( 95% ), when you use highly efficient speakers..... you listen at 3/4s of a Watt or less.

Why compromise the majority of your music listening time, ( eg. 95% ) using a "clunky " sounding tube ( 300B, Type 50, 845, etc . ) for an event that might occur infrequently??

Also consider : the really good amp's power band, from 0.75 Watts to 2.00 Watts, will handle about 90% of that infrequent content, in a properly wired audio system.

The path to excellence, in my opinion, starts with your speaker's efficiency. 101dB or higher gets it.

Generally speaking, the highly efficient speaker, allows a person to employ the best-sounding audio amplifiers.

The audio amplifier is the weak link.

There exists a very large listening and performance difference - between what is possible, amp-wise today, and what is commonly used.

Thanks very much - for considering my view point / audio orientation. I hope that it helps others.

 

[ssf]

Why compromise the majority of your music listening time, ( eg. 95% ) using a "clunky " sounding tube ( 300B, Type 50, 845, etc . ) for an event that might occur infrequently??

Are you saying this for a Tube amp or for any amp ?

I am not someone who has a lot of experience when it comes to speakers and amplifiers. I feel that there are only a handful of a very few senior members who own or have owned very high sensitive speakers and have paired with low wattage tube amps.

There could be many reasons for this like availability of equipment, availability of space in which to place the speakers which I am assuming are quite big and availability of funds to do such a purchase.

Hence, most of us end up with small bookshelves with small drivers with low or medium sensitivity and thus go looking for higher powered amps to drive them.

Your post is well taken though.

 

[Kannan]

For one, to state that high efficient speakers sound the best is factually incorrect.
Be it high efficiency or low efficiency speakers, the way the speaker produces the sound remains the same, the difference being one needs higher power to be pushed depending on the voice coil, cone material and the Gauss and some other factors.

As long as both produce the same SPL at say 1 meter the ear would hardly know how much power it is being driven with. 1 watt or 100 watt if the THD is well outside audible limits, it does not matter to the ears.

Each speaker design, be it full range or multi-way remains a trade-off here and there with some perfections and imperfections.

For those who prefer only tube sound, a high efficiency speaker makes both economical as well as build sense due to complexity of designing amps with high power tubes.
That said I had last year heard a NAT Audio GM hundred DHT tube based amplifier driving a pair of floor standing ROSSO speakers in AVLounge showroom and the experience was breathtaking.
I have also extensively heard 15 or 18 inch Altec Alnico based theater speakers from the 60s driven by a DHT very low power amp and also with a SET Class A SS amp. It was also a great combination and the music was enjoyable.

The cost variance between the above 2 setup is quite humongous and so was the performance difference.

For someone totally into tube sound, taking the high power route can be challenging due to complexities of taming very high voltages especially if you are looking at Single ended topology.
Here high efficient speakers help in choosing tube with lower power.

When one takes the SS route, the cost of power per watt is very less now, though still a Class A design will be large for higher power due to poor efficiency. Class AB and especially Class D has matured immensely.

So now due to advancement in technology and miniaturisation and increased efficiency, we have amplifiers that can be conveniently matched with power hungry speakers.

Also Class D has made way for active speaker designs where the manufacturer/user can have full control to fine tune the setup in the digital domain with sound processors.

 

[drlowmu]

Hello Kannan,

YOU WROTE ABOVE :

"For one, to state that high efficient speakers sound the best is factually incorrect.
Be it high efficiency or low efficiency speakers, the way the speaker produces the sound remains the same,"


I agree with your first sentence 100%. But..... you have somewhat misunderstood / or misinterpreted my postings !!!

If you re read my posts, I never stated anything quite like that - about high efficiency speakers - being superior !!!

I stated there is no problem with the loudspeakers, and that the weakest link .......... is the amplifiers.

I went on to say the best sounding amps are 2 Watts or less, and it requires a high efficiency speaker...... if you want the best overall audio performance.

I now always suggest, to start your audio system with 101dB or higher speakers, not because these speakers are the best, but because it allows you to use the best sounding amps, which will be 2 Watts or less.

In my experience, in the low powered amp realm, the awards will go to certain tube amps, over the best in low powered solid state designs.

I am thinking in terms of solid state amps built by someone like Nelson Pass, VS: tube amps built by Dennis Fraker ( both in the USA ). Or possibly a DIY tube amp I might build. Tube amps, at their highest levels of design and execution, do beat the solid state amps, 2 Watts or less.

- - - - - - - - - - - - - - - - - - - - - -

There exists one exception ( I have personally-heard twice at audio shows ), to my above postings.

The million dollar complete MBL ( Germany ) home hi fi system, to my ears, sounds wonderful. It is comprised of their Radialstrayler electrostatic omni speakers, and their MBL high powered solid state power amps.

Will anyone reading this, buy this MBL complete system and give it as a gift, for me to use???

 

[Kannan]

I went on to say the best sounding amps are 2 Watts or less, and it requires a high efficiency speaker...... if you want the best overall audio performance.

What i have mentioned is that 1 watt or more watts makes no difference to sound quality as long as the power is clean without distortion.
A speaker for producing 70db at 1 meter may need 1 watt or more watts depending on its efficiency and other parameters, the ear does not care as long as the delivery is clean.