dcmo Posted June 5, 2005 Share Posted June 5, 2005 Assuming that a amp has 400 watts of total output, how many watts would it be putting out if the volume control was at the half-way position. Would it be putting out 200 watts per channel, or is it dependant on the source. If it is putting out 200 watts, would it be putting out 200 watts to all channels or only to the Mains. The RF-7's are rated at 250 continuous, the RC-7 at 200, and the RS-7's at 150. If I'm putting out 200 watts into the RF-7's, are the RS-7's also receiving 200 watts. Are the RF-7's held back by the RS-7's if this is the case. Sorry for all the rambling, I wasn't quite sure how I wanted to word this. Anyway I thank you all for your help, I'm sure I will have other questions on this matter as it becomes clearer. Quote Link to comment Share on other sites More sharing options...
dodger Posted June 5, 2005 Share Posted June 5, 2005 There is no pat answer. There are a number of variations: The first is whether you measure at the amp or at the end of you Speaker Cable, The next is resistance or ohms - an eight ohm speaker two way or three way is not flat throughout the spectrum. You can vary from 5- 10 ohms. Then where exactly is middle - with tolerances middle can vary the percentage allowed by the manufacturer. With the amp, whether you measure at 4,8, 16 ohms may vary. There are more, but this gives you an idea. I'm sorry that there's no ACTUAL answer, unless you measure output at half, see where your volume setting is. But then you have to make sure that the input signal matches the stated. And lastly you have to be sure how linear your volume tracking is along with what frequency you're putting out. A number of amps give a great output at 100 Hz with the variations at other frequencies. Welcome to the Forum! Quote Link to comment Share on other sites More sharing options...
r.cherry Posted June 5, 2005 Share Posted June 5, 2005 i think the total amps are divided among all channels, how i know not. ie 700 watt total amp running a 6.1 channel system would have about 100wpc. Quote Link to comment Share on other sites More sharing options...
dcmo Posted June 5, 2005 Author Share Posted June 5, 2005 I guess what I am really getting at is if my mains are currently receiving 200 watts (I know it's loud, it wouldn't stay that way for long. just enough to rock out a little bit or to show off the system) on average (Sunfire Signature: which would double at 4 ohms and double again at 2 ohms), are my surrounds and center also receiving 200 watts which would overload the RS-7's. As far as the volume control is concerned, I guess what you are saying is the only way to know how many watts are going thru the amp at that time is to use a SPL to figure out the decibel level being played. Quote Link to comment Share on other sites More sharing options...
ygmn Posted June 5, 2005 Share Posted June 5, 2005 simple answer... If you were to over drive the speakers...(any of them) and the amp had sufficient clean power....your ears would bleed before you did damage.... Now if the amp power is struggling...and distorted and clipping...then you may damage speakers....but it would sound like crap.... Quote Link to comment Share on other sites More sharing options...
dcmo Posted June 5, 2005 Author Share Posted June 5, 2005 "If you were to over drive the speakers...(any of them) and the amp had sufficient clean power....your ears would bleed before you did damage.... Now if the amp power is struggling...and distorted and clipping...then you may damage speakers....but it would sound like crap...." And that is where the problem lies. Currently I have a Pioneer Receiver (the Sunfire hopefully by the end of July) which has a setting of -80 to +12. During a cd playing of The Wall live I've had it up as far as 0 which definitely puts a little fear in me so far as burning out the receiver. Pioneers are supposed to be pretty accurate (mine is rated at 100 watts per channel, so I figure it puts out around 70 watts per channel) so I assume I'm putting out about 40 watts (again assuming the wattage is based on the amplifier and not the source) per channel. The RS-7's are rated at 150 continuous, and if they are getting the full 40 watts all I can expect would be another 6 DB increase overall. 6 DB's are on the small side of what I want (more like the ability of ten), at least as far as the mains are concerned. If all speakers receive the same wattage, then an increase of 6 DB's would be the limit without damaging the RS-7's. I know I'm rambling again, but I guess what I really want to know is if my mains are receiving 200 watts (it's a large room and my listening position is about 4 meters) are the surrounds also getting the 200. Thanks to all for your help and your patience. Quote Link to comment Share on other sites More sharing options...
IndyKlipschFan Posted June 5, 2005 Share Posted June 5, 2005 Not to be silly, but I miss the old days where you started at zero and at 10 it was at full volume. Course some had a joke about theirs going to 11 as well, so a LOT louder!! I some what understand from GIL to say -60 to 0 (full power) the + 12 gets some what scarey!! Is this overdrive like a tube guitar amp at this point? I assume with certain pre amps, a certain signal level means this or that to the amp, and if you switch manufactuers or amps does it still send the info like it would with the other? Sometimes switching manufactuers might not get you good results if so. All we have done IMO is confuse a lot of people with this sillyness. IMO, it should still be Zero means off, Ten means full bore throttle. Quote Link to comment Share on other sites More sharing options...
J.4knee Posted June 5, 2005 Share Posted June 5, 2005 Also in surround sound not all channels are going at the same signal level in the program source. So even if you were delivering a full 200 WPC to your mains as your eardrums begin to burst you may very well not be delivering it to you surround speakers or center. It would depend on what to source material contained and how it was mixed. Or more directly to the point what the dynamic range of the input signal was Quote Link to comment Share on other sites More sharing options...
Spkrdctr Posted June 6, 2005 Share Posted June 6, 2005 The wattage going to your speakers, or technically going through your speakers is very dependant on your source material. Also, the frequency makes a huge difference too. But, to answer your question is general terms, no you are not overdriving your speaker by turning your Pioneer reciever up. You are causing it to clip though. Clipping that will toast a voice coil IS NOT usually heard as sounding crappy. Your reciever can clip quite regularly and sound very good until a speaker driver unit cooks a voice coil. I would recommend no more than about 60% percent on the volume knob or -15 on your knob as the max volume for long duration listening. If you want to demo your system loudly for a short time, then you can crank it up higher but you will be clipping. If the sound is crappy from clipping, you have "massive" clipping and you most likely will toast something fairly quickly. The Sunfire will not have these limitations. It will pretty much put out whatever you need within reason. Unless you get volume crazy,(I mean totally insane) you will generally not hurt your speakers with a Sunfire unit. I hope this info helps you out. Quote Link to comment Share on other sites More sharing options...
DrWho Posted June 6, 2005 Share Posted June 6, 2005 ---------------- Assuming that a amp has 400 watts of total output, how many watts would it be putting out if the volume control was at the half-way position. Would it be putting out 200 watts per channel, or is it dependant on the source. If it is putting out 200 watts, would it be putting out 200 watts to all channels or only to the Mains. The RF-7's are rated at 250 continuous, the RC-7 at 200, and the RS-7's at 150. If I'm putting out 200 watts into the RF-7's, are the RS-7's also receiving 200 watts. Are the RF-7's held back by the RS-7's if this is the case. Sorry for all the rambling, I wasn't quite sure how I wanted to word this. Anyway I thank you all for your help, I'm sure I will have other questions on this matter as it becomes clearer. ---------------- ---------------- I guess what I am really getting at is if my mains are currently receiving 200 watts (I know it's loud, it wouldn't stay that way for long. just enough to rock out a little bit or to show off the system) on average (Sunfire Signature: which would double at 4 ohms and double again at 2 ohms), are my surrounds and center also receiving 200 watts which would overload the RS-7's. As far as the volume control is concerned, I guess what you are saying is the only way to know how many watts are going thru the amp at that time is to use a SPL to figure out the decibel level being played. ---------------- Ok, let's look at the sensitivity / power handling of each speaker: RF7 = 102dB / 250 watts RC7 = 98dB / 200 watts RS7 = 98dB / 150 watts The sensitivity is how loud the speaker is with 1 watt of power. To make the math easier, I'm going to do calculations assuming the RC7 and RS7 are 99dB sensitive isntead of 98 (you'll see this in a second). Off the bat, I'm going to mention that a 3dB increase in volume = a doubling of amplifier power. Ok, so in my reciever I've got my mains set to 0dB (we're talking the balance controls for each individual speaker). Since the RC7 and RS7 are "99dB" efficient (just to make the math easy), we need to put their channels to +3dB. This is of course assuming that each channel is equidistant from the listening position. Anyways, this means that the center and surrounds need twice the wattage of the mains in order to play at the same volume. So at 102dB the mains are getting 1 watt and the center and surrounds are getting 2 watts (double the amp power due to 3dB difference in sensitivity). In order to play at 120dB (which is very insanely loud...louder than any rock concert you'll go to), the RF-7 will need 32 watts, whereas the center and surrounds will need 64 watts. At this point I would just stop and mention that we can easily achieve 120dB within the power handling of the speakers and therefore not worry...as long as your reciever can put out 100 watts per channel. Typically, recievers give more power to the mains and less to the center and surrounds. So if you have 400 watts of total output (assuming 8 ohms), then your reciever probably has 110 watts available for each main channel (so 220 total for the mains), and then the rest of the channels probably have somewhere around 60 watts (3 x 60 = 180 and 180 + 220 = 400). Solid state amps generally sound their best when driven at least below half their max output (aka, a minimum of 3dB of headroom). I personally think 10dB of headroom is a better number, which means your reciever should be able to at least put out a solid 110dB from your center and surrounds (64 watts = 120dB, so 110dB gives you 10dB of headroom, which is only 15 watts). All that said, your reciever should be capable of volumes that will make your ears bleed. 110dB is about how loud a typical loud rock concert is. I personally find 90-100dB to be a more comfortable listening level which is in the 1 to 5 watt range for your system. When turning the volume control, it will move in about 1dB increments and adjust the wattage output to the speakers according to how you set their relative volumes. So in our example, if you're listening at 102dB, increasing the volume to 105dB means the mains are going from 1 to 2 watts and the other speakers are moving from 2 watts to 4 watts. (every 3dB change is a doubling of amp power). Here's a chart to make things easier to visualize: Quote Link to comment Share on other sites More sharing options...
dragonfyr Posted June 6, 2005 Share Posted June 6, 2005 Just because I like turning over apple carts, I would like to posit a that there exist better ways of viewing this entire subject! Amplifiers don't 'put out' watts! Has any one ever noticed that the output from light bulbs, speakers, amplifiers, space heaters, heating blankets, toasters, microwave ovens, and any number of devices are commonly, and with the exception of the heaters, erroneously rated in watts? It is a marvelously useful unit of measure, IF we want to know how well electrical energy is converted to heat energy! Now the last time I checked, and with only a few exceptions, I have not found myself gathered around my stereo seeking warmth in the form of heat! (Ok, ok, the tubes do give off a bit too much heat! ...and they are much to hot to sit on...ok - another thread!) And I can find much more efficient forms of radiant heat energy! And to my best recollection, no one has ever asked me how loud my 60 watt light bulb gets! Nor my toaster or microwave! Hang on while I run and check! So while I am not going to waste time describing what useful units describe what amplifiers do provide, just as the wattage of a light bulb does NOT indicate how much light energy is generated (that is what lumens, lux, or candlepower are for!), neither does the wattage of an amplifier or a speaker tell you the sound pressure level! Perhaps its time for us to move beyond these nomenclatures and explore other more appropriate avenues (and units!) that better assist all in providing more useful measures of output in the realm of audio. Quote Link to comment Share on other sites More sharing options...
cdsang Posted June 6, 2005 Share Posted June 6, 2005 I would also like to add something. So we can see the chart and at so many watts equals so many dBs. But what about RMS and peak? If you have a 100 dB/1 watt/1 meter speaker using 1 watt RMS, it could reach to 4 watts on peaks with music and in some cases more. Just going by my simple example, an amp truthfully rated at 100 watts per channel, you may not be able to use more then 25 watts RMS due to peaks. Just to explain a bit. 1*2=2,2*2=4 watts. So at 4 watts useing my example speaker, would make 106 dB. To continue on with example speaker and amp that speaker at the RMS 25 would hit about 114 dB with peaks of about 120 dB. I have heard music can have peaks of 10 dB, so your RMS would be even less on that kinda music. All this is just what I think anyway. So if this maybe true, a 1000 watt amp running a song with 10 dB peakes may only be able to use 100 watts RMS. And I have this forum to thank for teaching me alot about this stuff. If I am wrong, please correct me. CD Quote Link to comment Share on other sites More sharing options...
Spkrdctr Posted June 6, 2005 Share Posted June 6, 2005 ---------------- On 6/6/2005 10:47:29 AM DrWho wrote: Solid state amps generally sound their best when driven at least below half their max output (aka, a minimum of 3dB of headroom). I personally think 10dB of headroom is a better number, which means your reciever should be able to at least put out a solid 110dB from your center and surrounds (64 watts = 120dB, so 110dB gives you 10dB of headroom, which is only 15 watts). All that said, your reciever should be capable of volumes that will make your ears bleed. 110dB is about how loud a typical loud rock concert is. I personally find 90-100dB to be a more comfortable listening level which is in the 1 to 5 watt range for your system. ---------------- Dr. Who, I cut out the major nuggets of pure wisdom in your last post. This should be required reading each week by every Klipschophile. These is a LOT of wisdom in those two paragraphs. If read enough, maybe people will actually apply it...... Spkrdctr Quote Link to comment Share on other sites More sharing options...
DrWho Posted June 7, 2005 Share Posted June 7, 2005 ---------------- On 6/6/2005 5:21:46 PM cdsang wrote: I would also like to add something. So we can see the chart and at so many watts equals so many dBs. But what about RMS and peak? If you have a 100 dB/1 watt/1 meter speaker using 1 watt RMS, it could reach to 4 watts on peaks with music and in some cases more. Just going by my simple example, an amp truthfully rated at 100 watts per channel, you may not be able to use more then 25 watts RMS due to peaks. Just to explain a bit. 1*2=2,2*2=4 watts. So at 4 watts useing my example speaker, would make 106 dB. To continue on with example speaker and amp that speaker at the RMS 25 would hit about 114 dB with peaks of about 120 dB. I have heard music can have peaks of 10 dB, so your RMS would be even less on that kinda music. All this is just what I think anyway. So if this maybe true, a 1000 watt amp running a song with 10 dB peakes may only be able to use 100 watts RMS. And I have this forum to thank for teaching me alot about this stuff. If I am wrong, please correct me. ---------------- Ok, so you have a sensitivity of 100dB "RMS" and you got a 10dB peak (let's call it a 12dB peak cuz i like easy math). That's 4 doublings of the power (2 to the 4th) or 16x the power. There's no way around it, a 112dB signal is going to have 16 watts going through it at that time (for this example of course). It's because of these peaks that it's good to have extra headroom in the amp, because SS sounds mighty nasty when it clips (not to mention it breaks stuff too). Most well built amps are also capable of producing peaks of output well beyond their RMS rating. I've seen 100 watt amps that can do 1000watt peaks (car audio does this all the time, even on decent sounding amps). Likewise, speakers too can handle peaks well above their RMS rating (provided the mechanical limitations of the driver are not exceeded). Now I know that I'm getting way too general here, but the reason we leave 10dB of headroom below the RMS rating is because the amp is usually more linear in that range. When you get into these crazy peak power ratings above the RMS, all sorts of nonliner stuff starts to happen and usually it doesn't sound too good...especially if you're hitting these peaks very often (once in a "long" while isn't as noticeable). Car audio is generally after max SPL instead of sound quality anyway Anyways, to make the point clear...10dB of headroom below the RMS rating should be more than plenty. And there's no need to fear damaging equipment because it should be able to handle short peaks above the RMS without breaking a sweat. I always hear mention about there being peaks in music that are supposedly like 20dB louder for nearly instantaneous amounts of time. I really don't have a firm enough understanding of amps to make this statement, but I think the effects are greatly exagerated. Amps have a slew rate which is the fastest rate at which the wattage can change...the slew rate also happens to limit the HF capabilities of the amplifier (if you can visualize a 20kHz sine wave versus a 20Hz wave, the 20kHz one is changing the voltage very quickly and you get more verticle slopes versus the gentle swooping of a 20Hz tone). I would think the slew rate of any amp would greatly round off such a peak in the music. I also want to mention briefly that most all digital recordings are well compressed and normalized to get every last bit of volume outta the CD. The medium itself can't even support a 10dB spike when the RMS of the music is around -6dB (you can't get a 10dB spike when the medium only has 6dB of headroom left). Now I know all recordings aren't like this and I'm talking generalities again, but it's something to keep in mind. (heck, I've got some classical recordings with over 20dB of dynamic range so I know what it's like). One fun thing to do would be to get a recording of pink noise recorded at 0dB (the loudest a CD can get) and measure how loud it is for different settings on the reciever's dial. This will essentially tell you the loudest any peak recorded on the CD can get for that setting. Then play normal music at that setting and take a reading of the average SPL and this will give you an idea of how much headroom there is between the average volume of the music and the loudest peaks. If you're listening to rock, the kick drum is usually up close to 0dB every time it hits, which you can then measure with your meter to get an idea of how much the meter lags (I think the rule of thumb is to add 10dB to short percussive sounds because the needle doesn' have time to move the whole distance...but really a different meter should be used for more precise measuring of these sounds). I can get some pink noise available for anyone that wants to try it out. Perhaps even put a CD together of some crazy changes in SPL and lots of dynamic range (just make sure the wife/parents/kids are away and wear earplugs) Quote Link to comment Share on other sites More sharing options...
Griffinator Posted June 7, 2005 Share Posted June 7, 2005 ---------------- On 6/7/2005 3:57:56 AM DrWho wrote: Perhaps even put a CD together of some crazy changes in SPL and lots of dynamic range (just make sure the wife/parents/kids are away and wear earplugs) ---------------- Might I suggest Mr. Bungle, Mr. Bungle. The opening 20 seconds contain a dynamic spike of over 20dB, and it's all over the map from there. Quote Link to comment Share on other sites More sharing options...
DrWho Posted June 7, 2005 Share Posted June 7, 2005 ---------------- On 6/7/2005 7:53:22 AM Griffinator wrote: Might I suggest Mr. Bungle, Mr. Bungle . The opening 20 seconds contain a dynamic spike of over 20dB, and it's all over the map from there. ---------------- Never heard of Mr. Bungle...what's it like? Quote Link to comment Share on other sites More sharing options...
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