Good analogy Cyclonicman. It's very informative to go out back at many Porsche dealers to see the latest rolled up in a ball because some idiot thought it'd go around any curve at any speed. MOST drivers are not qualified to drive a Porsche at speed.
Maybe most audiophiles don't have sufficient sensitivity to set the volume control properly. Frying speakers is shouldn't happen if amps are used with care and levels are set at musical levels.
Dave |
"When is an amp overkill for a speaker?"
I guess the simple answer is: when it overdrives or fries the speakers.
Practically, however, in most cases fried speakers are a result of not enough power resulting in clipping. And, if the speaker is being over driven at a volume you like, then get another pair of speakers. |
Some funny posts here! I don't understand how an amp can have too much power, when you can control it!! I find a more powerful amp is like comparing a Porsche to a family sedan. They will both get you to 60mph, but the Porsche will do it more efficiently with a lot less effort. Certainly, you shouldn't push the amp beyond the capacity of the speakers, but more power is a good thing, in the right hands! |
Audiograils, Audiofool does not care what others think of him and his posts. He is the authority and knows all. It is best to just ignore him, but I must say that I find it difficult to follow my own advice. |
LOL, Destep. It sure does remain an amusing exchange, especially if you like to see Pit Bulls in the ring. These guys are made for each other, I think. Substance v form! And the winner is? :-) |
Audiofeil, I can see what some of the readers here think of you...you just keep digging more holes for yourself.
Over'n'Out.
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Hah!!! Very funny exchange guys. That was very entertaining for me. |
Thanks AG but I think the readers know who the rookie is in this thread. |
Audiofeil, seems you're still a rookie or you just didn't understand what I said. Either way, you still have a lot to learn! My point is very clear since speakers differ in size, internal volume, number of drivers etc..
FAS, would you drive a single-driver Lowther with an amp like a Krell FPB600 and claim that it's not 'too much power' for that speaker??
I think folks should stay away from you !!
Best Regards,
AG
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DF is limited at low frequencies by the choke in series with the woofer (0.08 Ohm typ.) to about 100 and by speaker wire inductance (0.5uH/ft typ) to about 10. It doesn't make much difference between DF=1000 or DF=4000.
Amp's DF at high frequncies is probably less important. Atmasphere, transformerless tube amp has DF=1.5 and the sound is exceptional (so I heard).
I would stay away from high DF amp (other than class D). High DF requires deep negative feedback - source of TIM and "transistor" sound.
Average power is only few percent of peak power. Only about 5% of this power goes to tweeter. It is rather difficult to destroy tweeter inspite of its small size. Tweeter gets damaged if you play test tones too loud, when your amp is saturating (flattened peaks=square wave=energy in high frequencies) or when your amp (or source) is oscillating at high frequency. The most common is damage caused by saturation when amp has not enough power. The best solution for that is to get amp higher rated than speakers or the amp with so called "soft clipping". Then you will loose woofer, midrange and the tweeter at the same time (just kidding).
Magfan - I've never had Maggies (space issue) but your efficiency doesn't look so bad. What is specified (SPL) at 1m is different at 5m. Typical speaker (point source) drops 6db when distance is doubled, but maggies are not the point source and drop is probably less than 6dB.
As for incredibly high power needed (according to article)at point of speakers impedance drop it is not so bad. The most of power demand in music comes at low frequncies (just look at the size of the woofer)and impedance drop is probably around 200Hz (most likely higher) - only fraction of peak power. |
>>'too much power'. It all happens when your amp is so powerfull over your speakers that the sound is 'choked' and the speakers can't breathe.<<
That folks, is really funny.
Stay away from this guy. |
I'd love a pair of Pass X1000's(1000W), but they're too powerfull for my Merlins(250w). |
Baroque_lover,
Thanks for sharing your speaker info. I used to have a pair of Accoustic Zen Adagio speakers which are similar to yours. My 50Wpc KT88 monoblocks drove them with ease.
The much larger woofers in my JM Lab Alto Utopia need more current to drive. Consequently, you need a higher power amp.
Saying an amp is too powerful is like saying a car too fast, a girl too pretty, too much money, too much fun, etc. :-) |
Yes, there's such a thing as 'too much power'. It all happens when your amp is so powerfull over your speakers that the sound is 'choked' and the speakers can't breathe.
I know many will disagree, but I experienced this phenomenon a few times along my audio years. Too much power and too little power is not a good thing.
I had to recently abandon a powerful 100 watter tube monoblock for a 30 watt stereo piece for just the same reasons. My speakers performed best with he 30 watter tube amp despite their spec numbers. Add to that, the sonics of the new amp were inherently better.
YMMV..!
AG
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Dave,
It is unwise to postulate. Then again, how else could someone justify their $9,000-1000wattperchannel-superintegratedamplfiier?
Vette93,
The speakers in question were the Totem Acoustic Forest.
I will reiterate: power is overrated and there is more to amplifier design then watts. |
Hello Stevechan:
"DF is simply load impedance divided by source impedance.
Nothing more"
Agree, withjust one very small clarification: this ratio is measured at one given frequency (industry standard). I believe its 1 kHz but I could be mistaken. My point is that if DF = 1,000 at one frequency then it can be 0.001 at another.
Thank you
Rafael |
Yep:Vett93, that was the point.
Now, extend the model to include speaker 'Q'..... |
I thought Magfan's test validated my view. LOL
A shorted woofer is like an amp with extra high DF. It does not make sound because there is no force continuously driving it. That is control!
Try to put a 4ohm resistor with high wattage rating in serious with your speaker. The amp still has the same output power. But the bass will be very distorted.
QED! :-) |
My understanding is Df matters but there is a wide tolerance in values that will work in any particular application.
You have to listen and judge. At least with dynamic drivers, if the bass sounds mushy or soft, a higher damping factor may help but the actual value does not matter that much. |
I think that DF is slightly more than nothing, but not near so much as most audiophiles attribute to it.
Dave |
DF is simply load impedance divided by source impedance.
Nothing more. |
Exactly Magfan. High power with low distortion equals control. A high DF helps only slightly in the control of the driver. The amplifier starts the drivers, accelerates them and decelerates them and stops them, all at a complex variety of frequencies. Doing all that with low distortion and ample power is key to control of the drivers.
Dave |
Yes, some bloom in the bass is nice. I've found live music has "bloom" too. The question is not if you need added bloom. Rather, if your amp had some bloom, would that sound more like live music to your ears?
The Lavardin amp can indeed sound like 500W monoblocks if the speakers are *very* sensitive and have a flat impedance curve.
My NP100 Platinum feels a bit lack of power when I play Beethoven Symphony No. 9, especially towards the ending. This is a time that I wish I had more power...... |
Baroque_lover probably doesn't need much power because, given his nom de plume, he only listens to baroque music. The demands are totally different from Mahler or even a Beethoven piano sonata.
He's right, he and I wouldn't buy the same systems because we have different priorities. IF you listen to very dynamic music, then power can be very important, particularly if you speakers can use the power.
Dave |
A SET amp may not control a woofer at higher SPLs but that has little or nothing to do with damping, which is a function of an amps low output impedence.
TEST:: take a bare driver...woofer prefered. Thump it with your finger. Rings nicely, right?
Now, take a short piece of wire and short out the connections. Thump it again with your finger. Little or no sound, right?
The woofer basically damps itself when its 'load'...the output of the amp, has low enough impedence. The rest goes up as heat.
As for control, doesn't audible distortion play into this? If you had a dual trace scope connected and could compare the input signal and the actual speaker motions, you could visualize it. the traces match?=good 'control'.
Traces don't match? Bad control. |
You probably like a little bloom in your bass, which is not uncommon. I listen to lots of music with tons of bass and I play in orchestras and bands with "real bass" so I don't like any added bloom.
DF is a technical term that doesn't adequately explain the ability of an amp to control the woofers. If your SET amp had a damping factor of 1000 it still couldn't control many woofers.
Dave |
I think ‘power’ is overrated in most situations. It is not necessary to have “1000 watt monoblocks” to achieve good [or great] sound. The Lavardin IT, rated at a modest 50 watts per channel in integrated form has sounded more organized and composed than some 500-watt (very expensive) monoblocks in side-by-side comparisons. It is true that some speaker designs require more power, and there are some esoteric brands that build speakers with these requirements. In your case this is not the case (sorry). But power is not the whole picture. Personally I would never buy a speaker with such requirements. |
What does "effective damping" mean then? :-)
I think what you are referring to is not damping. Rather, it is the sheer power.
I have 4 amps in the house, from 8Wpc 300B SET to 200/400Wpc into 8/4ohm load all SS power amp. The damping factor ranges from 5 to 700. I would not say a higher damping factor will yield the best bass for all kinds of music.
I've found that for Jazz and string music, a mid level DF will yield the best bass to my ears. A high DF means a dryer bass, again to my ears. |
It depends.
On room size, how loud you listen. That's about it.
Realize that power alone is not always the answer. The amp has to be able to deliver power smoothly into the speakers variable impedance at different frequencies. Amps that double in power from 8 to 4 to 2 ohms do this best. Some speakers are more difficult to drive due to complex impedance loads at various frequencies. Others are less demaning. |
09-13-08: Vett93 said:
"What does "more control of bass" mean? If you meant sufficient current to drive the bass woofers without more distortion, then it is equivalent to a higher SPL. If you meant a higher damping factor, then it is independent to the wattage anyway."
I'm talking about effective damping, not damping factor. DF is part of the equation, but a 100 wpc with a damping factor of 1000 isn't going to control the woofers as well as my 1000 wpc amp with a DF of 1000. Someone up the thread said something along the lines that watts are like horse power. There's something too that.
Uncontrolled bass is too bloomy and resonant. An amp that grabs the woofers and prevents them from uncontrolled ringing is what's needed.
Dave |
Vett93, You have learned something of great value, I think. Now to have an even more complete understanding of amp/speaker matching, consider that not only do speakers have an irregular impedence so do amplifiers have an output impedence that is irregular. Not so much SS which usually have a very low output impedence and its not a real issue, but tube amps can, and do, have output impedences that are fairly high and can make a substantial difference in what you hear from speakers. It's has been discussed here before so some night when you can't sleep, it will give you something to research. :-) |
I think it all depends on the speaker and amp combo. The Spectron Musician III SE in mono-block delivers 2400watts @ 4ohm. I do have to set the volume nob down than when I had only one M3 SE stereo amp, but the level of detail, effortless sound and fitness is world class.
Reports of blown tweeter fuses on the Maggies 3.6R are not that uncommon. I've read cases where the tweeter fuses blows up with an 800watt amp. I mostly listen to Jazz and Classical music, so it's unlikely that I'll go up to uncomfortable levels. But listening as loud as my room allows, I've never blown up a tweeter fuse with the 2400watt Spectron mono-blocks.
You can check the technical details of safety features for this amp, which may help to explain why I never feel anything forced upon the sound. All I perceive is the easiness of the music, just like a live musical event.
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As to the magazine article referred to- I beg to differ that the phase angle is all that important - the proper term for what is imporant is the group delay. |
What does "more control of bass" mean? If you meant sufficient current to drive the bass woofers without more distortion, then it is equivalent to a higher SPL. If you meant a higher damping factor, then it is independent to the wattage anyway.
I have learned the following things recently.
I bought my current speakers, JMlab Alto Utopia, with the impression that they are easy to drive: 91dB and 8ohm load. But my KT88 monoblocks, 50wpc, couldn't drive them well. Upon more investigation, I found the speaker impedance drops to 3.2ohms. This means that bass will need 2.5X more power than the mid-range.
Then I bought a Counterpoint SA100 and upgraded it to NP100. Note that NP100 has several upgrade levels and they all have the same rating, 100Wpc into 8ohm and 170Wpc into 4ohm, with a damping factor around 40. I have tried the following upgrade levels: Basic, Basic Gold, Premium Gold, and Platinum. They sound *very* different even though they all have the same outout ratings.
So what have I learned?
1. The matching between power amp and speakers is very important.
2. The amp rating can be misleading at times. |
Great info here everyone. I think I know what direction to take... the good thing about buying used is I can always resell without taking much of a loss. I'll update you.
Joe |
Read carefully and keep it as your guide:
http://www.enjoythemusic.com/magazine/manufacture/0708/index.html
All The Best
Rafael |
There's something to be said for effortless sound....1800 watts a side. But it is a two edged sword....you can waste a tweeter. I know...years ago I played Copland's "theme for a common man". Cranked er up and the gong toasted a tweeter....learned my lesson.....Kinda like jumping on a Porsche turbo with the HP on the lurk....bad idea. |
For some audiophiles and some politicians:
To much power you say?
"No such thing" they answer |
09-13-08: Shadorne said:
"For your current speakers 140 is far enough - same if you upgrade. Frankly if you need more SPL then get a bigger speaker (three way) rather than overdrive a small one - your little speaker will be mostly distorting when driven hard."
More power is not about SPLs, it's about control of the drivers, particularly in the bass. Listen and decide for yourself.
Dave |
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For your current speakers 140 is far enough - same if you upgrade. Frankly if you need more SPL then get a bigger speaker (three way) rather than overdrive a small one - your little speaker will be mostly distorting when driven hard.
FWIW: If you are looking at really old amps then it may be worth having it checked out and possibly replacing the caps. |
A million watts is probably too much. |
I'm definitely not the most estuste audiophile, or even really an audiophile, but to me wattage is somewhat like horsepower in a car. You don't need a lot of horsepower to get to the speed limit, but most of us still would like to have some extra if we need to push it. I'd rather have and not need, than need and not have. |
I have had two types of problems with excess power:
1. Too much gain for my speakers efficiency due to not being able to turn the preamp down enough (KEF speakers, CAT pre, Symphonic line amp). CAT's rather crude volume pot gradations of 3 db or so made one click too low and the next, too high. Also, if you use a TacT or some other digital volume control, a high powered amp into some speakers will have you throwing out bits of resolution when you turn it down, due to the digital nature of Pots.
(I know, I know, for all you TacT afficianadoes out there, TacT manipulates this in the software or something, but I don't need to hear about that here. Take it to the TacT forums. I'm making a point, not selling or defending TacT products.)
2. Many and esp, less expensive volume controls don't "track" the two channels well at lower settings, say below 10-11 o'clock or so. These controls need to be up higher in their range or you will have erratic channel balance.
That's why we call them "systems", each part is more or less interdependent on the other parts. All that said, I like big power sometimes (Soundlabs with Perreauxs at 850 per side, Genesis 501 with Pass 350, totalling 1200 watts per side) I don't mind power.
However, I'm using Lowthers at 105 db in the cabinet and 2 watt 45 tube amps, or even weirder, my First Watt f4, which has a -.5 db gain structure! That's perverse to my last 3 decades seeking power and gain, but lower power=fewer gain stages=cleaner power is a convincing argument when you've acturally heard it.
Nonetheless, you're looking in the big horsepower league. If that's what your system needs and responds to, then I agree: "one can't be too slim or too rich" and you can't have too much power, IF it is under control and properly applied.
Different horses/different courses. |
Jtnicolosi,
You listen to the two kinds of music that require the greatest power reserves - classical and rock. You need lots of power. Think about it, rock is typically performed with several thousand watts of power, huge speaker systems and full drum kits. The wall of sound and chest thumping beat is what gives rock music its power to move you, whether it is in your living room, a bar or a stadium. Classical music, especially full orchestral pieces, rely on 80+ musicians drawing strings, blowing on woodwinds and beating on kettle drums and cymbals. Crescendos in classical music require tremendous amounts of fast power to replicate the scale and speed of all those different instruments and energy operating in unison. Not only that, but multiple speaker drivers to move significant volumes of air don't hurt either.
The problem is a trade off between adding more components (capacitors, resistors, diodes, etc.) to increase power, and the value of simple circuits in terms of noise and distortion. Smaller scale and lower energy music like acoustic jazz and vocals requires less power to reproduce lifelike scale and transients, and the extra power capacity just adds unnecessary noise. I agree with some others here that an important issue for you is the need to reproduce low frequencies at a realistic scale. For the kinds of music you like, I think the sensitivity of your speakers is less important than the amount of low frequency energy present in the signals you are trying to reproduce, and the ability of your amplifier(s) to lord over the woofers in your speakers and move air.
140wpc versus 200 wpc is not really as critical as the current and dampening factor provided by the amplifier. For example, the Naim Nait 5i with 50 wpc channel provides as much or more control in practice than many 100+ wpc amps, because it seems to be able to deliver current quickly and efficiently to the speakers.
How much power is too much power? In your case, more than you need to reproduce the music of your choice, whether it is the Who or Mahler's 2nd, with convincing scale and drama. For classical and rock, I doubt you will find that point of diminishing returns below about 100 amps of current delivery and a dampening factor of about 500, regardless of the sensitivity of your speakers. |
Power is a testosterone experience in that some like big things, in this case power/watt numbers. Here is the math. To go up 3db, you need to double your power. At 91db, you are at 1 watt and you would be at 8 watts when you are at 100db...that is loud. The only advantage to power is whether it is highly biased into class A, then you would be running into class A up to perhaps 10-20 watts before switching into AB. All the watts will keep Edison, PG&E and company happy. Bottom line is that more power=more noise==more problems due to more transistors or more tubes=more money. I like lower power as long as it is controlled. Me, tubes, tubes, tubes. Jeff |
Newbee says::
FWIW, if you've got the money, and you are not giving up sound quality, having high power reserves in not a bad thing. But high power high quality amps cost a disproportionate amount of money for the power you get but don't use.
Exactly my point. With reasonably sensitive speakers, you simply have little need for mega power. Sure, I'd love a pair of Mac monoblocs or a pair of BelCanto Ref1000's.....a full kilowatt each into my Maggies, but why bother? With my Maggies at what....? 85db, I'd need 4x the power for the same result as Jtnicolosi with his 91db speakers.
Take the difference in money, and buy some more music and maybe work on the room. |
I like Musicnoise's post and agree about the Mahler, but actually think that just about any well recorded Mahler will do. The Finales of #1 and #6 will test any system.
I'm a little surprise about the comment about piano sonatas. Well recorded piano has tremendous dynamic range, including loads of bass.
Dave |
A Accuphase P200/P300 don't even worry about it....if there qaulity drivers the amps won't be a problem...btw the Accuphase amps have built in protection circuits for driving unsafe loads. |
As I always say to this kind of question "nothing exceeds like excess...."
Enjoy,
TIC |
