Tune Up

Discussion in 'Tonefreaks' started by onehippie, Aug 23, 2010.

  1. onehippie

    onehippie Senior Member

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    Marc Noel-Johnson

    "Recording electric guitar can be a tricky business, especially for those who are either completely new to the recording process or those who make music using sampled instruments and loops, and who want to add guitar to tracks already recorded. The purpose of this article and the ones that follow on the same subject is to give anybody new to the technique of recording guitars a basic idea of what’s involved but without getting too technical.

    There are phrases you will come across in articles about this subject which will mention things like ‘phase cancellation’ and ‘comb filtering’. These are quite technical subjects and outside the scope of this article. We will talk about them another time, but for now we’ll concentrate on the basic concepts that a beginner has to grasp.

    There are four main elements to consider when it comes to miking an amplifier, either at home or in a studio – microphone placement, the type of microphone, the room acoustics and most importantly, the sound of the amp itself.

    Like all recorded sound, the source material must be good. The idea that a poor guitar sound can be fixed up later is erroneous, and time will be wasted at the mixing stage, leading to frustration and dissatisfaction with the result. Added to that, if you’re not happy with the guitar amp you have, or it’s too big to lug upstairs to your bedroom studio, or playing it at any usable volume will whip up the neighbours into a murderous frenzy, miking may not be the best way to go. If so, skip to some of our more recent articles about using pre amps and modeling devices.

    Many amplifiers have a DI (Direct Inject) output on the back. In my experience, connecting this output directly into a recording device is a waste of time and will yield poor results. What we want is the sound of the speaker moving some air. Modelling amps are an excellent option for recording, as signature tones can easily be dialled in. But my favourite recording tool has to be a low wattage valve amp, especially if the output can be stepped down (that is, retaining the tone but reducing the volume).

    Most speaker cabs and combos will yield better results if they are isolated from the floor, possibly on an acoustic isolation pad. This stops resonant bass frequencies or rumbling, which may not be audibly detectable but will certainly appear on the recorded track.
    With that, you’re ready to get started.

    Before you start recording electric guitar, it’s worth taking the time to individually consider the factors mentioned in part one of this guide and ask yourself some pertinent questions. Arguably the most important is: what are my room acoustics like and how are they affecting the sound I’m hearing? The general rule is that a dead space will yield better results than a live one – you can always add spacial effects like reverb and delay later.

    To get a true picture of your sound, get down in front of your amp and listen to the difference in tone as you move your head off the speaker axis. It’s also crucial that you find out where the centre of the speaker is and mark it with a piece of masking tape. Also mark the edge of the speaker. Place your microphone on axis (that is, directly pointing at the centre at 90 degrees) and make a recording. You will probably find that the sound is aggressive and harsh. Move it out to the edge and repeat the process. The sound will probably be less harsh and a little muddy. Try placing the microphone somewhere in between, at an angle. The result should be a more balanced tone altogether.

    As far as distance goes, a dynamic microphone will enhance the low frequencies as it is moved nearer to the sound source. This is called the proximity effect. If the microphone is too far away, the room acoustics or ambience will affect the sound by adding in unwanted reflections and unpleasantness that you will not be able to remove. Of course, these are only general guidelines and experimentation is necessary as there may be a few other factors involved. For example, if you are using a 4×12 cabinet, then there will be one speaker that sounds better than the others.

    A word about volume – if possible, record at the highest possible volume, but take care not to overload the input of your DAW or soundcard. A small amp turned up will sound better than a big one just barely running. The optimum power for a recording amplifier in my experience is between 15-20 Watts. I would try to avoid anything with a speaker smaller than 10 inches.

    Consideration should also be given to just where the particular guitar part I’m recording is going to fit in the track. If it’s a background rhythm chop or a single chord per bar accent I would back off any distortion otherwise it will just get lost in a busy mix. Clean, chorus or arpeggiated parts will need to be very clean at source with the bass rolled off. Solos, particularly those using distortion, will need the mids boosted to bring them to the front. Meanwhile, saturated rhythm is appropriate for hard rock and metal tones, which have ‘scooped’ or reduced mids with a full bottom end. A 4×12 cabinet would be ideal for this sound.

    Most people recording at home will not have the luxury of an isolation booth to mitigate the effects of room acoustics and volume considerations. But for a quick fix, try putting your combo in a wardrobe full of clothes, or an airing cupboard. If it’s in an adjacent room then so much the better – you can monitor through your speakers rather than headphones.

    So you’ve learned about microphone placement and how to use your amp, but which microphone should you reach for?

    The Shure SM57 is arguably the one microphone that most top producers and engineers can agree on when it comes to recording electric guitar. Generally considered to yeild optimum results, it’s a dynamic microphone, so doesn’t require phantom power, and is as tough as they come, not to mention cheap. If you spend a lot of time recording guitars, it’s an essential investment. Having said that, any decent dynamic will work and there are some very affordable options out there.

    Condenser microphones can be used to mic up amps as well, but care should be taken as the diaphragm is delicate and can be damaged by high sound pressure levels (SPL). If you use a condenser, you will have a choice of three settings – cardioid, figure of eight and omnidirectional. Set it to cardioid, otherwise you will pick up a lot of room noise, cars going past and dogs barking.

    If you use both a dynamic and a condenser, set the condenser back a little bit from the speaker grill but not too far away. The reason for this is that recording a single sound source into two microphones placed too far apart will produce tracks that are out-of-phase (out of sync) with one another. Phase cancellation is when the signals or soundwaves from the microphones are out of alignment causing the ear to get confused.

    Here’s how it works: imagine two identical dogs in front of you, both barking constantly but not in sync with each other. The resulting sound is not easy to listen to and in audio terms translates into an unpleasant, unfocused noise. Anyone embarking on this path of double miking should be aware of the possible problems and do some in-depth research on the subject.

    Elsewhere, ribbon microphones should be avoided. They are quite delicate and will simply not stand up to the SPLs emitting from a guitar amp speaker.

    If possible, try to record the guitar dry, unless the effect is so relevant to the part that it simply won’t work. Most DAWs, whether software based or a hard disc recorder, will have excellent guitar effects built in. Alternately, these effects can be bought or may be included as plug-ins. You will have more of a chance making your guitar sound fit with your track if you leave the effects off until you are nearing the mixdown stage. At the mix, you can add effects, probably compression first. Used properly, this will make your guitar ‘sit’ in the track. Reverb should be avoided for as long as possible, as it will give a false sense of where the guitar track is in the mix.

    A useful trick is to simply duplicate the track once recorded, and then delay one of the tracks by the smallest amount possible. Pan the two tracks left and right and your recording should start to sound big. Another technique is to position a microphone in front of an unamplified electric guitar and play the song through again on another track. When mixed in, this will add top end sparkle if you use a high pass filter and roll off the low end.

    Also, make sure that all of your solos are recorded as hot as possible. If they get lost, you can lift them out of a busy mix by boosting the upper mids – use a parametric EQ with a narrow ‘Q’ and move it around until the part is distinct. It’s better to use EQ like this rather than just boosting the level, which will simply detach the part from the mix."
     
  2. 767400

    767400 Senior Member

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    Thank you for all that great information.
     
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  3. onehippie

    onehippie Senior Member

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    you bet
     
  4. 1981 LPC

    1981 LPC Senior Member

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    Dan Erlewine's book 'How To Make Your Electric Guitar Play Great!' comes with a very informative video of him doing a set-up and explaining things as he goes along.

    There's a link to the video here: guitarwise See 2/5th from the bottom of the page.
     
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  5. DorothyHick

    DorothyHick Junior Member

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    It's a very artistic statement.
     
  6. lineboss58

    lineboss58 Senior Member

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    Or you could buy yourself a peterson.
     
  7. onehippie

    onehippie Senior Member

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    [ame=http://www.youtube.com/watch?v=Y3haYAbqKjA&NR=1]‪Johnny B. Goode - Chuck Berry‬‏ - YouTube[/ame]


    [ame=http://www.youtube.com/watch?v=gsp4VCbVvn4&feature=related]‪Roll Over Beethoven - Chuck Berry‬‏ - YouTube[/ame]


    [ame=http://www.youtube.com/watch?v=IH8IrcvdiD8]‪Rock & Roll Music‬‏ - YouTube[/ame]


    [ame=http://www.youtube.com/watch?v=eTnoSsaeOn0&feature=related]‪Chuck Berry - Reelin and Rockin‬‏ - YouTube[/ame]


    [ame=http://www.youtube.com/watch?v=p0HmFr7mPsk]‪Chuck Berry - Maybellene (live 1958)‬‏ - YouTube[/ame]
     
  8. longan

    longan Senior Member

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    This is fantastic info!!! I don't have any string changes coming up but next time I'll use this
     
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  9. onehippie

    onehippie Senior Member

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  10. smorgdonkey

    smorgdonkey Senior Member

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    Lots of excellent info there but I have never heard of that 'tune down to the note' method on locking tuners. In fact, all locking tuners that I have ever had were treated the same as all others...and that it tune up to the note. I never had even the slightest issue.

    So, if there is a mechanical/design reason for that prescribed method, I'd like to hear it.
     
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  11. onehippie

    onehippie Senior Member

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    could be not having to re tighten the extra wraps now not present
    the statement may be only the initial one at a time re-stringing of guitar a tension thing maybe
     
  12. onehippie

    onehippie Senior Member

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    CTF


    "How To Tune The Guitar To Perfection"

    The following is a reprint of THE GUILD OF AMERICAN LUTHIERS data sheet #45.

    "Many guitarists are frustrated because of their attempts to tune the guitar to pure chords (free of beats). These particular players have very sensitive ears that prefer pure intervals and reject the mandatory equal temperament. They tune their guitar beautifully pure on one chord only to discover that the next chord form is unacceptable. In too many instances they assume that there must be a flaw in the workmanship on the fingerboard. Their problem is not in the construction of the guitar. It is one of pure tuning verses equal temperament.

    You must accept this compromise because the guitar is an instrument of fixed pitch and the strings must be tuned to tempered intervals, not pure. Equal temperament is the name given to a system of dividing the chromatic scale into 12 equal half steps. Guitarists who have been trying to tune to one or another pure chord form must learn to understand and accept equal temperament. (They might be interested to know that to approximate pure chords on all forms would require about three dozen frets within the octave.) The system of equal temperament reduces the number to twelve, thereby making manageable all instruments of fixed pitch.

    Here is what all of this means to the guitarist: You must not, at any time, use harmonic tones at the 7th fret as a point of reference (skilled piano tuners could use them because they know how many beats to introduce between 4th and 5th). Harmonic tones at the 7th fret are pure 5ths, while in equal temperament each 5th must be lowered slightly. To tune by harmonics at the 7th fret (as occasionally ill-advised) will make the guitar sound entirely unacceptable on some chord forms.

    On the other hand, all harmonics at the 12th and 5th frets, being one and two octaves above the open strings, are immediately useful as explained below. All octaves and unisons are pure on all instruments of fixed pitch. Therefore, you may use harmonics at 12th and 5th as reference tones in the following tuning instructions.

    Actually this discussion and the following suggestions are for those players who have been tuning to pure intervals. When the steps have been followed correctly the guitar will be as perfectly tuned as it could be in the hands of a professional. Nevertheless, when you have finished, your sensitive ear may notice that on each major chord form there is always one tone slightly high. If you start adjusting a particular string on a certain chord form, you only compound the problem because then the next chord form will be completely objectionable. Tune the guitar as instructed below and let it stand. How to help your ear accept equal temperament: It is easier to face a problem if we are prepared in advance and expect it. If you are one of those persons who is sensitive to pure intervals, here is what you are going to notice on an absolutely perfectly tuned guitar in equal temperament: Play an open E major chord. Listen to G# on the third string and you most likely will want to lower it very slightly. Don't do it. Ignore it. Enjoy the overall beauty and resonance of chord just as does the pianist.

    That troublesome second string: Play an open position A major chord. Listen to the C# on the second string and you may want to lower it slightly. Play a first position C chord and listen to the E on the first string and fourth string at 2. These tones are slightly higher than your ear would like.

    Now play an open position G chord. Listen to B on the second string. Yes, it would sound a little better if lowered ever so slightly. Why not try it? Slack off the second string a couple of vibrations and notice what beautiful G chord results. Now play the C chord and with that lowered second string, and you are going to dislike the rough C and E a lot more than before. Take the open B, second string back up to equal temperament so that it will be equally acceptable on all forms. Learn to expect and accept the slight sharpness of the major third in each chord (and oppositely, the flatness of the minor third in each minor chord). Train your ear to accept tempered intervals and you will be much happier with your guitar.

    PROCEDURE:

    Tuning the 1st and 6th strings: The E, open 1st string, must be in pure unison with the harmonic of the E, 6th string at the fifth fret. When these two strings have been properly tuned with each other, continue as follows. Tuning the 4th string: Play a harmonic on the (in tune) 6th string at twelve, and as this harmonic sounds, adjust the 4th string until the tone E on the second fret is in pure unison. Now you have the E, open 1st string, 1st on the 4th string at two, and E, open 6th string tuned pure (permissible because they are octaves).

    Tuning the 2nd string: Play a harmonic on the (in tune) 4th string at twelve. As this sounds, adjust the 2nd string until D at the third fret is in pure unison. As you have used two fretted tones for references and as the frets are positioned for tempered intervals, you now have the open 1st, 2nd 4th and 6th strings in tempered tuning.

    Tuning the 3rd string: As it is easier to adjust a string while listening to a continuous reference tone, you may first try the following: Play a harmonic on the (in tune) 4th string at twelve and as this sounds, adjust the 3rd string until D at the 7th fret is in pure unison.

    Double check: Now make this check to see if you have been accurate or if the instrument plays tune when fretted at seven. Play a harmonic on the (now tuned) G string at twelve, and as this tone sounds, play G on the 1st string at three. The two tones should be in pure unison. If they are not, either you are at fault or the instrument doesn't fret tune at seven. Go back to the beginning and carefully check each step up to this point. If the tones are still faulty, then readjust the 3rd string until the harmonic at twelve is in unison with the 1st at three. Do not tamper with the 1st and 4th strings because it is the 3rd string you are trying to bring in tune. When you have the 1st, 6th, 4th, 2nd and 3rd strings in tune, in that order, continue with the remaining 5th string.

    Tuning the 5th string: Play the tone A on the (in tune) 3rd string, at the second fret. Listen to this pitch carefully and now adjust the 5th string until the harmonic at twelve is in pure unison. When the foregoing steps are followed correctly, the strings will be tuned perfectly to equal temperament. No further tuning adjustments are permissible."


    Thanks to Judge Vasco for the heads up on article
     
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  13. onehippie

    onehippie Senior Member

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    hope you found it useful

    take care
     
  14. jimbob137

    jimbob137 Senior Member

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    I got a Peterson Stroboclip a few weeks back. The sweetened tunings sound really nice, really made my guitars sound better. Makes you realise that chromatic tuners are only for ruffing in.
     
  15. onehippie

    onehippie Senior Member

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    when high/low signal is separated
    the cleanness of the cut should determine the smoothness/roughness of the remaing high,mid
    and low frequency range to switch then output? right at the pots 2 lug on vol
    to the sound and possibly control too
    less or more a disturbance in flow
    do materials effect the cut signal?(cheese) say mylar/pio/ceramic disk etc.
    not saying good or bad either way whatever you have available
    this i wonder

    22 would determine amount give or take?
    voltage how much cap could do without exploding?
    these 2 are kinda seperate


    would there be an affect on signal
    like 2 knives different blades with smoothness roughness of surface microscopically different cutting say
    the same block of cheese and when looked at microsc... there would be different surface texture to surface of cheese
    lesser quality surfacing to blade and edge creating a rougher surface maybe even visually and the feel of it grabbing the cheese
    it seems cap construction / materials fingerprint it at least
    how the remaining highs are sculpted and presented

    efficiency of expected texture
    wouldnt even on ten the leakage to cap like pots of even a small amount of highs effect the signals final being
    the mid and high frequency range would be right at this point of event

    if this incorrect im here to learn

    any thoughts
    __________________
     
  16. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    Cut off frequency is often classified as -3db below peak frequency and can be calculated, but no mention of different materials effecting outcome.

    [​IMG]

    Calculating the -3 dB*cutoff frequencies - given center frequency and q factor bandwidth in octaves 3 db bandwidth frequency filter octave 3 dB bandwidth calculator - sengpielaudio Sengpiel Berlin

    A high filter quality means narrow-band filtering (notch), with a large Q factor.
    This results in steep filter flanks with a small bandwidth.

    A low filter quality means broad-band filtering, with a small Q factor.
    This results in flat filter flanks with a large bandwidth.

    [​IMG]
     
  17. onehippie

    onehippie Senior Member

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  18. onehippie

    onehippie Senior Member

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    great call yesterday from jonesy

    cleared everything up and then some
     
  19. jonesy

    jonesy GLOBAL WIRING GURU MLP Vendor

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    Yeah always good chatting with you bro!
     
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  20. onehippie

    onehippie Senior Member

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    speaker and amp fun

    "Secrets of Amplifier and Speaker Power Requirements Revealed
    As audio/video hobbyists, most of us grew up thinking that if we have an amplifier with 50 watts of rated output power into 8-ohm speakers, and that combination produces reasonably clean and loud music, then by doubling the amplifier power to 100 watts per channel, the system would then play twice as loud. Many readers likely still believe that. Not so.

    Although it's not the easiest thing to comprehend, doubling the amplifier power does not double the loudness. In the above example, the sound from the speakers would not be "twice as loud"; it would only be "a little louder," an increase of 3 decibels. How loud is that? Hearing tests with large groups of people have revealed that a one-decibel (1 dB) change in loudness is approximately the smallest audible step that the average listener can detect, so an increase of 3 dB most listeners term "slightly louder."

    So why doesn't that 100-watt amplifier always sound twice as loud? Because the acoustic decibel--the decibel (dB) being the unit of measurement used worldwide to quantify the acoustic loudness of sound--has a peculiar relationship to amplifier power output measured in electrical watts. That relationship is called "logarithmic." If that word gives you an instant headache (nightmares of high-school math), then here's a simpler explanation:

    If a sound gets louder by 3 decibels or "slightly louder," it takes twice as much electrical power from your receiver or amp to produce that modest increase. Therefore, a 100-watt amplifier will produce sound only slightly louder than a 50-watt amplifier.

    Incidentally, if you'd like a kind of immortality, be terribly clever and work out a system of measurement. It may be named after you. The "decibel," one tenth of a bel and named for Alexander Graham Bell, recognizes his contributions to the understanding of sound. Likewise, we have to thank James Watt, Georg Simon Ohm, and Heinrich Hertz for their contributions to the industry. And then there's the Lofft, a measurement of neighbors' tolerance to testing new speaker systems . . .
    So far, so good. But what if it's party time, and you're listening to music "very loud," a level defined as about 90 dB Sound Pressure Level (SPL), and your speakers are gobbling up swings of 15 to 20 watts per channel on those musical peaks.

    Drink in hand, you advance to the volume control on your receiver thinking, "I'll just crank this up to make the music twice as loud," and you turn up the volume control until there's a 10 dB increase in the sound level. Now your party-time goal of "twice as loud" will make huge electrical demands on your nice little multi-channel receiver or power amp. The receiver must deliver ten times as much power to double the subjective loudness. Between 6 dB and 10 dB is double the volume level, where 6 dB is four times the power and 10 dB is 10 times the power. In the aforementioned example, the amp must produce 150 to 200 watts per channel for those peaks in loudness. Therefore, every 10-dB increase in acoustic loudness--from 80 dB to 90 dB, or 90 dB to 100 dB--requires ten times as much electrical power in watts.

    That's all very well if you have a monster amplifier or multi-channel A/V receiver with huge reserves of power output (most of us don't). If not, watch out. Your receiver or amp may "clip" or distort (or both), which will put a clamp on the output of the amp. When you push your amplifier into overload or "clipping," several things may happen. First, the top and bottom of the waveforms (representing the audio signals) are clipped off, generating distortion. Next, the amplifier's protection circuits are activated, removing those portions of the signal that are causing the overload, generating distortion. And finally, the amplifier's power supply may fluctuate according to the demands of the music signals.

    Not everyone is affected by this scenario, of course. Some people (increasingly few, it seems) don't listen to loud music. They like background levels, and with average speakers, background levels demand 1 watt or less of amplifier power. Or they may have very efficient speakers (Klipsch, Cerwin-Vega, Tannoy, and the like) that will play extremely loud using modest amplifiers, the trade-off being a very large degradation in tonal accuracy, a definite harshness, and a complete loss of off-axis performance that accompanies horn-loaded designs. But in many situations, speakers will be damaged and distorted sound will offend many ears.

    No discussion of decibels, acoustic loudness, and electrical watts is complete without an explanation of loudspeaker "sensitivity." (Another way to define a speaker's sensitivity is to look at how efficiently the speaker converts electrical power, in watts, to acoustic sound output in decibels.) Let it be said in a general way that speakers are not very efficient or sensitive devices. They need a lot of electrical power input to produce relatively little acoustic output. Nevertheless, speakers do vary quite a bit in sensitivity.

    To determine a speaker's sensitivity, we feed the speaker with 1 watt of amplifier power, using a test signal of pink noise, and measure in decibels how loud the sound is at a distance of 1 meter (about 3 feet). A lot of domestic hi-fi speakers measure in at about 89 or 90 dB SPL at 1 meter. Larger speakers, with bigger woofers and more drivers, typically produce greater acoustic output; smaller bookshelf models have to work harder, and their output is typically less, often between 86 and 88 dB SPL at 1 meter.

    Placing the speaker in a room helps (the walls, ceiling, and floor reflect and reinforce the speaker's sound), adding about 4 dB to its output. For example, a speaker like Axiom's M80ti has a measured sensitivity in an anechoic chamber of 91 dB SPL at 1 watt at 1 meter. But putting the M80ti in a room raises its sensitivity rating to 95 dB SPL at 1 watt, 1 meter. A 95-dB sound level happens to be "very loud," as most of us would subjectively describe it. And it is--from 3 feet (1 meter) in front of the speaker. But let's move our listening seat back twice as far, to 6 feet. Guess what happens? We instinctively know that sound gets weaker as the distance from the source is increased, but by how much? A formula called the "inverse square law" tells us that when the distance from the source is doubled, the sound pressure weakens by 6 dB. Among sound engineers, there's a common saying: "6 dB per distance double." So at a 6-ft. distance, the M80ti is now producing 89 dB. Now let's double that distance again to 12 feet, a fairly common listening distance. The speaker now produces 83 dB, which isn't all that loud at all. And if you sat 24 feet away, a not uncommon distance in big rooms, the speaker would produce 77 dB SPL.

    But what about stereo, I hear you shout. Here's another oddity of loudness and the decibel. When one speaker is producing a level of 90 dB, adding a second speaker playing at the same level only increases the overall loudness by 3 dB! (The loudness does not double!). So the two speakers in stereo produce a loudness level of 93 dB.

    So adding a second M80ti will raise the loudness at 12 feet from 83 dB to 86 dB. And don't forget we're still using 1 watt of amplifier power output into Axiom's most sensitive speaker. But how loud are real-life instruments, orchestras and rock bands? Now, while 86 dB SPL is "fairly loud," it's not nearly as loud as what you might hear from a good seat at an actual rock concert or from an orchestra or pianist in a concert hall. A solo grand piano can reach peak levels of 109 dB SPL, a full orchestra and chorus in a concert hall will measure 106 dB, and a rock group, 120 dB SPL. Now let's try and get our peak speaker sound levels to 96 dB, "twice as loud" as our 86-dB listening level. That isn't that difficult because right now we're only using 1 watt per channel to drive the M80ti's to 86 dB. So we'll need ten times as much power, or 10 watts, to reach 96 dB. Big deal. We've got lots more.

    But things begin to change, and rather dramatically. Let's push the M80ti's to what we might experience from a solo grand piano, 109 dB. We're at 96 dB with 10 watts per channel. Let's go to 106 dB. So that requires 10 x 10, or 100 watts. Close, but not quite there yet. Just 3 dB more. Remember, we have to double the power for a 3-dB increase in sound level. So 100 watts becomes 200 watts. Yikes! Our receiver has only 110 watts maximum output! We've run out of amplifier power! And what about the rock concert? Let's lower our expectations and aim for 119 dB. Going from 109 dB SPL, which needs 200 watts per channel, to 119 dB SPL (get out your ear plugs) is another 10-dB jump and--you do the math--that requires 10 x 200, or 2,000 watts per channel!

    From all this you can see the huge power requirements inherent in reproducing real-life acoustic sound levels in average or big rooms. The M80ti's are tested to levels of 1,200 watts of input power so they come very close. But the truth is that if we are seeking real-life acoustic sound levels in our listening rooms, there's a very persuasive argument for very large, powerful amplifiers. And if your speakers are less sensitive (and many are), then the power demands rise even more dramatically. Sizeable rooms and greater listening distances will also increase power demands tremendously.

    And what many of us don't realize until we hear it, is that clean undistorted loud sound often does not sound that "loud." The key here is that in most or our home listening, there are small amounts of distortion caused by a lack of dynamic headroom (but more on that next month). It's the distortion that makes it sound "loud" in a domestic setting. To remove those distortions and increase dynamic headroom relates to even more power. We've become accustomed to accepting some distortion with our reproduced music, because all amplifier's distortion ratings gradually increase as they approach their output limits or slightly clip the audio signals. When that happens, we turn down the volume, because distortion starts to intrude on our listening pleasure, and it sounds "too loud."

    The lesson in all this is that you can never have too much power, and that big amplifiers rarely damage speakers. Little amplifiers driven into clipping burn out speakers. In the scheme of high fidelity, that last barrier to realism is having enough power and being able to approximate real-life loudness levels."
    [​IMG] Alan Lofft,
     
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