Sorry, but the speaker manufacturers and hi-fi world in general have fed you so full of irrelevant BS it is easier to just ask, what is that you have now, and what are you trying to do?
How many watts??
If I have a 80 watt stereo amp and I normally listen at quarter volume and never play at levels higher than this. Do I really need 80 watts could I use a 15 watt amp at half volume?
My next question if I have speakers that my mfg states needs min 50 watts to really make them sound good with my current amp rated at 80 watts but played at qtr volume does that mean I am not really getting the best from these speakers. If I play at half volume this is too loud, do I need a bigger room. Sorry if I did not explain clearly enough.
My next question if I have speakers that my mfg states needs min 50 watts to really make them sound good with my current amp rated at 80 watts but played at qtr volume does that mean I am not really getting the best from these speakers. If I play at half volume this is too loud, do I need a bigger room. Sorry if I did not explain clearly enough.
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VU Meters were all the rage in the 60’s and 70’s… McIntosh being one prominent adherent well into today. Big reason why they were dropped was because a lot of people noticed they were not using that much power to “swing the needles” So trying to sell a triple digit amp when people were armed with knowledge didn’t seem like the path capitalists wanted to take. Some manufacturers even build power hungry speakers just to sell their big watt amps… see above for example. The total power of a amplifier should be taken with the knowledge that you should have enough headroom for dynamic passages. Lots of amps will run in pure class a for the first few watts. You also should take into account the load the speakers present. Inefficiencies will require power. For example, you could run a pair of very efficient horn speakers, like Klipsch with a modest few watt tube amp and enjoy satisfying volume. |
If I have a 80 watt stereo amp and I normally listen at quarter volume and never play at levels higher than this. Do I really need 80 watts could I use a 15 watt amp at half volume?An oscilloscope might tell you what the maximum voltage is you are presenting to the speakers. Once you know that, then you could make an objective decision. Or just hook up your amp and subjectively determine if it sound good to you. |
In general more power is better. Watts are relatively meaningless if you desire good quality sound. Lots of current is a better indicator. If an amp, say, doubles the wattage with decreasing impedance it is a high current amplifier. But basically the higher quality the amplifier the better they sound. There are different designs that sound somewhat different. |
"...Some manufacturers even build power hungry speakers just to sell their big watt amps…" You got that backwards. Loudspeaker manufacturers like Magnepan and Infinity made loudspeakers that just ate up amplifiers. Then the race was on to see who could build big arc welding amps. Some of the first players were, Ampzilla, BGW, Bose1801, and others. |
In reviewing your question, I believe you are focusing too much on the OEMs guidance for the speakers. Speakers can be damaged by 'clipping' which can be done by an amplifier that is below the recommended wattage rating. I have a VU meters on my amp and when playing music in the background when guest are over for dinner the amps rarely deliver more then 3-5 watts. I prefer to listen to music loud when alone and staying around 100 or so watts requires my volume knob to be in the 60-70% of full volume range depending on the source and the recording. Therefore, are you enjoying the sound? When you turn the volume up or down slightly are you noticing characteristics change in tone, timber and tempo? |
As has been said by others... More information is needed, specifically what are the speaker's rated sensitivity. If the sensitivity is low (below 87dB) then you'll need more amp power than speakers with higher sensitivity (above 90dB). Digging deeper, you'll need to know the speakers impedance across the audible frequency range, because speakers have impedance peaks at different frequencies. This is where an amp's current rating comes into play and how well it can provide power through high impedance loads - which in many cases are spontaneous frequency-based loads that will affect sound quality and overall audible response (high-pitch cymbal crash causes a spike in impedance and suddenly the bass is affected because the amp can't provide the power). In other words, to best answer the question, the make and model of the amp and the speakers is needed to offer the best answer to your question. Another point is about the description of 1/4 volume and 1/2 volume. This is meaningless because most integrated amps and preamps do not have linear volume control - in other words, 1/2 volume knob adjustment is not necessarily 1/2 volume. I'd completely disregard volume knob fractional increments with respect to actual SPL. More power is almost always better for sound quality (and loudness) because of the increased head room for instantaneous dynamics. But what matters even more is quality amplification - look for amps that can deliver more power into ever decreasing impedances down to 2 ohms. Example: The NAD C388 integrated amp is rated: 8 Ohm 250W 4 Ohm 350W 2 Ohm 400W Please note this example is not high-end by 'audiophile standards' - as a matter of fact it would likely be considered mid-Fi, and is so loaded with features that many are gasping right now that I even mentioned what might be considered a borderline 'lifestyle' product. Its essentially a extremely supped-up Bluesound PowerNode with display, phono stage, dual sub outs, line level outs, MDC card expandability, etc. Whenever I'm shopping for amps, the first must-have is 2ohm stable; otherwise, its obsolete soon as those demanding (low-impedance) speakers catch your eye. |
On jasonbourne comment about running horn speakers with 200 watt amp--is that necessarily a bad thing? My only experience with Klipsch speakers was at my brother in laws house in another State, and he was using an AVR to drive them that he proudly told me was "500 watts" (probably one of those promos that added all the watts across each channel). I absolutely hated the sound--every instrument sounded like a saxophone or trombone to my ears--but I always wondered what they might do if driven by one of those 10 watt tube amps. |
Your 80 wpc amp drives your 87db sensitivity speakers rather easily at your preferred volumes; and it has reserves for instantaneous needs. a less powerful amp would be a mistake IMO. If you like those speakers, I would be tempted to upgrade to their 9.5 speaker https://www.dagogo.com/salk-sound-ss9-5-speaker-review/ ................................... to answer your question: it is Logarithmic: a lot of additional power is needed for a small amount of volume increase. https://geoffthegreygeek.com/amplifier-power/ +3db = a perceptible volume increase. double the WPC needed for +3db volume, i.e. a lot for a little. to double the volume needs 10x WPC. thus 10x is needed for 2X |
The great Robert Harley famously said, "If the first watt isn't any good why would you want 200 more of them?" This is wisdom. We have heard the amp with fewer watts sound much better in every way than the amp with more watts, over and over again. Not always! Not saying lower power is better. Not saying there are no really good sounding high power amps. Simply saying watts are not the reason. |
Maybe this related to power and sq. I have noticed when listening at friend's system which is much more sophisticated than mine when listening at higher levels we can still talk to each other comfortably at the listening distance approx 12 feet from speakets without raising our voices too much . And the music seems more 3 dimensional. When in contrast at my place as I turn up the volume we can't talk to each other as well. Not sure if it is the quality of his system vs my system or room interaction his vs my room. |
Many amp designers say amps tend to work at their most linearity at around 20% of their full rated output. As has previously been posted, volume increases require logarithmic power output. Having an additional 80% of total power output for headroom is prudent. Running out of power; can lead to clipping; clipping can lead to speaker damage. Speaker sensitivity, room considerations and desired volume levels will ultimately determine how much power one needs. There used to be an oft repeated audiophile general rule of thumb; "double the manufacturers minimum power recommendation". |
Hello, I usually listen at modest volumes. Probably 60-70db and even a lot lower at sometimes. I was never impressed by playing loud. I am more impressed by how low you can play the volume and still hear the full dynamic range. One way to cheat this is add a subwoofer so you can still hear that deeper bass. I will tell you the preamp or preamp portion of an integrated amp is most important. More important than 80 watts or even 1000 watts. The amplifier is amplifying what the preamp sends it. Garbage in, garbage out. If you hear a his, hum, or distortion why would you want to amplify that. I have seen a 10w per channel integrated tube amp rock out. You should try it. But it’s the preamp, not the amp doing that. Your system is amplifying garbage from the preamp. If you can hook up a good preamp to your system you will understand what I am saying. If you are in the Chicagoland area borrow a Rogue preamp from this store to hear how good your system can sound. https://holmaudio.com they let you demo in your home before you buy. No more buyers remorse. |
Watts are only one small part of the overall equation of how much power an amp has. Too many people get hung up on watts and db’s. Yes numbers can be a good starting point but never stop there. Example 1 watt from a class A amp is nowhere close to 1 watt from a class D amp. Its like comparing the horse power of a lawn mower to a motor cycle. The number can be the same on paper but the end product is nothin alike. |
Its like comparing the horse power of a lawn mower to a motor cycle. The number can be the same on paper but the end product is nothin alike. Yeah… I agree that my John Dear mower is nothing like a Kawasaki motorcycle. They are both green, and have engines, but after that… James Watt, who coincidentally standardised the unit of Horse Power, later the “metric horse” became labeled as being Watts and kilowatts… So to claim that a watt is not a watt, only means something in the context of asking a two different 1W amplifiers to give 2 watts… and how they clip. I quest that the OP likes it quiet. The average person needs the 50W amp that the manufacturer recommends. And there is another Gaussian tail of people on the right, that will blow the speaker apart. We can call these the 65dB, 85dB and 105 dB groups… or the A, B and D groups. |
Your brain interprets distortion as volume. It can be any distortion coming from the system or the room. You have work to do. @russ69 , Hold on Tex, you are forgetting about Crown and Phase Linear. They were the first to make amps over 100 watts. The Crown sounded like finger nails down a chalk board. The Phase Linear like to blow up if you tried to drive the wrong speaker with it. The semiconductors of the day could not handle the heat and the Phase had pathetic heat sinks. But, it sounded 1/2 way decent and it did not clip into large Advents at 100 dB or so. Both amps had these large fancy face plates but were only a few inches deep. They may have weighed 5 lb at the most. As compared to the Parasound JC 1 at 65 lb, serious light weights and the JC 1 is a relatively light amp! The big Boulders weigh over 300 lb most of it CNC milled Aluminum of no sonic significance what so ever not to mention fugly to my eye. |
I own a set of Dahlquist DQ10s....a notoriously hard to drive speaker. Before I bought them, did some research. Everyone kept saying, "you need at LEAST 200 watts to drive them". I had no desire to purchase one of those arc welding, heat producing monsters. Then a technician with 40 years in the field chimed in and told me he's owned 4 sets of the 10s at various times. Told me the best performing and sounding amp he'd heard them paired with was a Proton D540.....40 watts wpc. It has a feature called Dynamic Power on Demand. NAD has a version of the same feature called Power Envelope. The Proton has reserve power of 160 wpc.......and that's at 8ohms. It will drive down to 2ohm loads. 6db of headroom. I had been listening with a Yamaha at 90 wpc but the Proton f'n blew that Yamaha away. I'm like you and don't like listening loud. I'm not sure what class amp the Proton is but the 10s sound glorious! The whole watts thing is b/s..... |
Hello, I can play my system at a little over 2% of the total volume and hear the dynamic range and stereo imaging on my system. One cheat to this is add a nice subwoofer or two. I like JLAudio or REL. I also have a JLAudio CR1 crossover so I can pick the crossover point of my front speakers to then hand off to the two subs. Some speakers have this crossover technology built in them like the new PSB T600 Synchrony speaker. I believe it has 5 crossover to produce a very good sound. Plus they play from 24 hz to 23khz. Paul Barton hit a home run on this line. The B600 bookshelf speakers are on another level too. At around $3k with stands these set the bar very high. Last but not least. You need to get rid of all that junk in your sound. Do you know there is a little more music in that album you probably are not hearing. If you would like to hear what you are missing demo a Puritan PSM156 or PSM136 power conditioner that comes with a really nice dissipative power cord unlike some other brands. If you have not heard Puritan has the Ground Master City that lets you take this plug and play system to another level. I am talking pitch black background. Sometimes I get up to flip the record before it’s over because the space between the tracks is so quiet. They are sold across the country. This is the store in the Chicagoland area that lets you demo in your home. https://holmaudio.com/ Basically, No buyers remorse….nice! |
Yes I once read an op Ed from a audiophile who stated that the sign of a good system was to see how low you could play the volume and still have it sound good. That's interesting. Because I heard a system one time so bad it gave me a headache. Literally had a headache driving home afterwards. It only sounded good when turned down to where you could hardly hear it. Okay frankly did not sound good even then. Turned off, then at least the room sounded pretty good. So I guess by your standard this was a really good system? |
I can drive an inefficient speaker with 44w/channel and it sounds great too at the 12 o’clock position… (The speakers are 84 or maybe 86 dB/W/1-meter.) If the OP is playing at 1/4 of the way up, it is not likely that they are playing it at more than 1W, and at that point… then what is the fascination with the speaker’s sensitivity and efficiency? |
The "OP" probably never gets past that 1st watt.... Almost all here fail to recognize just how much actual energy a transducer can output at (1) full watt. OR just how often all that they are listening to normally? All is supplied by that 1st incredible watt. "For many". Even with speakers rated (85db) sensitivity! |
If I have a 80 watt stereo amp and I normally listen at quarter volume and never play at levels higher than this. Do I really need 80 watts could I use a 15 watt amp at half volume? No, it depends on the input levels and your amp's gain. If your input level is very high, you could exceed your amplifiers output even when your volume knob is lower than half volume. It the input is very low, you could possibly not even come near your amplier's total output even with the volume turned all the way up. There is no "golden ratio" between amps. ... if I have speakers that my mfg states needs min 50 watts to really make them sound good with my current amp rated at 80 watts but played at qtr volume does that mean I am not really getting the best from these speakers. No, the manufacturers are engaging in a CYA exercise. The "best from your speakers" is what sounds the best to you. Don't sweat it, sit back and enjoy your sound. You are over thinking things. |
Your volume control is most likely logarithmic so you cannot use that as an indicator. Go to Home Depot, Lowe’s or Amazon. Order a volt meter. Set the meter to AC voltage and measure the voltage across the speaker terminals while playing. This will tell you how many volts you are using. Amps or current drive is volts divide by speaker nominal resistance. Power is amps time volts. Most modern music is fairly compressed so 6dBs or a gain of 2 and 9dB or a gain of 2.8 will do. A gain of 10 is 20dB which is way more than you will need. |
The volume knob is just a gain attenuator in the preamp section of your amp and has NOTHING to do with understanding how much power your amp is actually putting out. You can't think that it's 1/4 turned, so you're using 20 watts. Your amp would have to have metering to show you how much power is being used, which is why many amps back in the 70s and 80s had them. It sounds like you've already got a good match between the power in your amp, the demands of your loudspeakers and how loud you care to listen. Relax. You're already set. |
Back in the late 60s ,100 watts a channel was unheard of then the 70s hit and the wattage started to increase...by 1975....if your reciever didn't put out 100 wpc...you received sucked...then it was 100-150-200 you were told you need more power 300 wpc ....now its 800 wpc to 1,000 Please stop the crap....tubes were always like 8 wpc to 15.....now you see 100wpc tube amps....Stop it ...its nuts and crazy......I gave polk lsim707 they say you need 300 wpc to achieve the sound you need ,I SAY baloney....I'm running them with a caryin 55 it puts out 30 wpc and it sounds great.. .I can't knock the walls down but I live in a condo village....and it plays loud enough for me.... |
It’s a balance between speaker efficiency (less efficient, easier to make accurate) and power requirements. More power generally allows faster rise to transients. The right balance depends on you personal tastes and listening habits. I have 140 watt per channel tube amp and my speaker sensitivity is 90db. I listen at ~70 db… I believe Audio Research is working on a REF 250, I’ll likely buy one. It will increase the dynamics of the system at all levels of play. |
Here's a decent guideline that I've used when calculating power needed/used. See the information below... Pay attention to the fact that most speakers rate their db-output at 1-meter and your listening position may be 3X that. You have to consider the drop in db from that measured position as well as how much amplifier head-room you need for your personal listening experiences. I also use a db-meter at my listening position and add 7db to the reading to get a good idea as to how much power I'm really using. For example, my speakers are 9-ft from the listening position. At 94db at 1-meter (assuming my speakers' rating is correct) I lose ~10db at the listening position. Adding 3db then since there are 2-speakers in the room I end up with -7db at the listening position. So, starting at ~ 87db (94db - 7db) at the listening position, at 1-watt of power, I need 16-watts of power for 99db sound at the listening position. I have a 10WPC solid-state amp and an 18WPC SET amp and most of my listening is in the 87db - 93db range at my listening position. So I have ~ 3db head-room with the 10WPC amp and about 6db head-room with the 18WPC amp. My 10-watt amp has only 1 output device/channel and is the most detailed and articulate solid-state amp I've ever heard on my system. The more output devices, the greater chance the subtle differences between them may cause subtle but audible differences in the music. High-end/high-quality mfg.'s (with correspondingly high $$$ cost) painstakingly match their output components to reduce this, however it's not perfect. This is one reason I've chosen efficient speakers and lower-powered amplifiers. I hope this information is helpful to you. Good Luck in making whatever corrections you need to ! Technical background to our dynamic range/power claims. This section is slightly technical and may take you a few minutes to read. We would like to take you through to the basic technical elements that make up a hi-fi system and explain how they go together. Loudspeaker sensitivity Loudspeaker sensitivity is a measure of how much sound a loudspeaker will give for 1 watt at 1 metre. It is critical to note that the basic measure of sensitivity is at 1 metre and not at a typical listening distance of about 10 feet or 3½ metres. Sound attenuates (reduces) over distance at the rate of 6dB with each doubling of the distance. At 2 metres distance from the loudspeaker its perceived sensitivity is reduced by 6dB. At a normal listening distance of about 10 or 11 feet from the loudspeaker its perceived sensitivity will be reduced by approximately 10dB. This is the factual basis for our claims about how much power a system would need for a decent hi-fi dynamic range. We reiterate that this is not made up or marketing hype, it is scientific fact. Loudspeaker sensitivity – is it real? Regrettably, most loudspeaker sensitivity ratings are not particularly accurate and are regularly overstated by 2 or 3dB. We have seen several examples of respected manufacturers’ products specifications overstating their sensitivity by 5dB or more. This does not sound like a big deal, but it has tremendous implications for the power required by the loudspeaker to deliver proper dynamic range. Amplifier power – confusion reigns. This is the source of much misunderstanding. Amplifier power is specified in watts, which are a measure of heating power. They have no apparent relationship to what we hear, as they are a linear measure. Loudspeakers (and our ears) perceive things in dB (decibel) steps. These are based on a logarithmic relationship. This is the fundamental mismatch between what your ears perceive and how amplifiers are specified. The solution to the problem is to recalibrate watts into dB steps. As you can
see, as soon as you calibrate amplifier power in dB watts, you get a dramatically different view of what
amplifier power really means. First off, you can see that what looks like a large increase in amplifier power, for example from 50 watts to 100 watts, only gives an increase of 3dB. Things get really interesting as when you get to higher powers. You start needing vast amounts of power for each dB step. For example, only 1dB (remember 1dB is the smallest change in sound pressure level that the human ear can perceive UNDER IDEAL LISTENING CONDITIONS) is the difference between 400 watts and 500 watts. If you really wanted to hear a difference above 400 watts you’d probably need to go to 800 watts (3dB) which should be audible. You can see why amplifier manufacturers want to sweep these figures under the nearest carpet; they make most of their claims look ridiculous as they predict that most loudspeaker/amplifier combinations will have only limited dynamic range. How much dynamic range do I need? Some years ago John Atkinson (current editor of the Stereophile) made some measurements of live music using accurate equipment. He recorded 109dB peaks (brass and percussion) and the quietest was 63dB (solo violin) a variation of 46dB from the quietest to the loudest moments – a huge dynamic range. The question is what sort of dynamic range a really good hi-fi system should have. In our opinion, an ability to produce unclipped peaks of 105dB is the minimum starting point for a really good hi-fi system. You are welcome to debate different figures, but that is our basic position. If you listen to small scale chamber music or usually listen at quiet levels, you will not need the peak capacity we deem necessary. But if you are trying to recreate the listening experience at reasonable levels, 105dB peak is not overly generous. How do you put all this together. Assuming that you have accepted the scientific facts this is how you determine what your system can produce. 1. Take your loudspeaker sensitivity (better yet check back to a technical review to find out what its sensitivity really is). Deduct around 10dB for the SPL (sound pressure level) attenuation over distance. And then add back 3dB because there are two loudspeakers in the room. Now you have arrived at the practical, real world, in-room sensitivity of your loudspeaker system. 2. Decide what peak level you want to achieve. We think 105dB is about right. Some people think 110dB is more appropriate. It’s up to you. 3. Deduct the result of 1 above from your decision about 2. This is how much amplifier power you require in dB watts General overview. None of this is intended as criticism of amplifier or loudspeaker manufacturers. You could regard it as a criticism of magazines and shops for not bringing it to your attention. We have been banging on about this for about ten years and many people have reacted adversely because they believed it was just marketing hype. This is not marketing hype, this is scientific fact. Many people do not like the result of a scientific analysis of their equipment but that does not alter the scientific facts. People have objected to our position claiming that their system sounds great. It might. However, you can’t escape the fact that, if they have a low powered amplifier and relatively insensitive loudspeakers, the system must be clipping, distorting and limiting regularly, which must dominate the listening experience. Maybe the listeners like distortion clipping. Well, each to his own and good luck to them. If you want your hi-fi system to produce as close an approximation to the real live performance as you can get, then you must ensure, for a start, that your amplifier is not clipping. |
If I may add to ^ @liquidsound 's post. Other considerations include room gain, which most will appreciate as an apparent increase in volume for a given power output. And that many loudspeaker's sensitivity is rated as 2.83V/1M rather than 1W/1M. This will mean that with each halving of impedance, the loudspeaker will lose 3 dB of sensitivity. For example: @ 8 Ohms 90 dB, @ 4 Ohms 87 dB , @ 2 Ohms 84 dB. To ensure linear frequency response at high volume levels, it behooves one to be sure that the accompanying amplification can meet the concurrent doubling of power demands beyond the standard 8 Ohm power recommendations. |
