pagan
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Post by pagan on Jan 30, 2012 11:40:22 GMT
[ I must show the wife this post before she goes in the cupboard!! [/quote] Just be worried if she come out of the closet.. Is it the amp or speakers/headphones? Out of all the equipment in the audio signal chain, what has the most distortion....? Easy, the speakers/headphones.
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Post by gommer on Jan 30, 2012 13:02:22 GMT
I wonder, y'all are talking about frequency domain distortion. What about timing anomalies (phase response).
I'm not sure amps are necessarily better than speakers/HP's in that respect.
Comments welcome.
Cheers, Marc
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pagan
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Post by pagan on Jan 30, 2012 13:35:47 GMT
I wonder, y'all are talking about frequency domain distortion. What about timing anomalies (phase response). I'm not sure amps are necessarily better than speakers/HP's in that respect. Comments welcome. Cheers, Marc What about the speaker crossovers?
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Post by gommer on Jan 30, 2012 14:25:10 GMT
Use fullrange drivers
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Deleted
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Post by Deleted on Jan 30, 2012 14:59:45 GMT
The better headphones vary (within 20 Hz to 20kHz) usually about 10 to 20 degrees and may swing to positive and/or negative at certain points in the frequency range. The behaviour is different in each headphone. Some can even shift over 60 degrees within the same range. Mostly it's gradual changes up and down across the spectrum sometimes more vigarous.
The phase shifts of tube amps and amps that have limited frequency response with cutoff points within the audible band can vary till 180 degrees but do so gradually near the ends of the spectrum.
The better amps (SS) with frequency ranges that are flat upto 100Kz and run well below 10Hz only might show a few degrees in the extremes of the audible bands.
Output resistance also has some influence in the audible range when it concerns phase shifts.
Tone control also causes considerable phase shifts.
The question is how audible phase shifts are at higher frequencies because when one moves the head just a tad when listening to speakers considerable phase shifts already occur in the higher frequencies. The hearing is quite insensitive to phase shifts at the lower end of the spectrum. Everything between 200Hz and 5kHz should have as little as possible phase shifts. Many (if not most) amps meet that expectation b.t.w.
HP's usually have no crossovers... in speakers crossovers have a great contribution as has the alignment of the speakers (tweeters more to the front woofers are recessed)
Indeed planar (full ange) speakers and headphones perform best as long as there are no transformers involved.
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Deleted
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Post by Deleted on Jan 30, 2012 21:24:43 GMT
Marc I agree Take care of that too in the amplification, and you can even hear reasonable surround sound via DTV and 2 good front speakers only. Due to hearing damge , I have different hearing between both ears, and I appear to be very aware of phase anomalies. Peter St. the XXHE playback software designer, and manufacturer of the highly regarded Phasure NOS DAC, also has similar abilities. We have both turned a liability to our advantage.Not surprisingly, Peter also hears these "impossible" things too. Regards Alex
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Post by Deleted on Jan 30, 2012 21:37:59 GMT
And so do lots of people who don't have the hearing affliction. You have the wrong thread I am afraid. This is not about timing errors in digital files but phase shifts in headphones and amps. a phase shift of even 1 degree is already literally thousands of times bigger than the 'suspected' jitter components (which are in the 100's ps range) and be equivalent to shaking the head hundreds to thousand times a second and moving only fractions a few micrometers (in a random order) to create the same effect. 100ps is a 10GHz modulation when talking about phase shifts. The intermodulation products that occur is another story and is not related to phase shifts but timing errors.
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Deleted
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Post by Deleted on Jan 30, 2012 22:10:09 GMT
Frans Almost everybody, ESPECIALLY you, adds a little extra that is not necessarily related to the OP in their reply to a specific post.Please check your own backyard is clean, before criticising others. ;D Regards Alex
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Post by Deleted on Jan 30, 2012 22:21:21 GMT
I just checked.... My tiles in the backyard have that green stuff on it. have to remove it in the spring... by that time the backyard is clean again. ESPECIALLY my backyard as I don't clean the tiles from the neighbours.
Awww getting of topic... sorry.
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Post by Deleted on Jan 30, 2012 22:37:33 GMT
Frans backyard; Alexs backyard;
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Post by Deleted on Jan 31, 2012 0:08:32 GMT
Frans backyard; Alexs backyard; Chris That is more likely Fran's backyard in the hottest month of the year. They are more likely to only have Trouser Snakes ? The other one is more like that of Robert KD in Rockhampton. We are more likely to have a big Blue Tongue lizard or very infrequently a deadly brown snake.
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XTRProf
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Post by XTRProf on Jan 31, 2012 4:04:15 GMT
The phase shifts of tube amps and amps that have limited frequency response with cutoff points within the audible band can vary till 180 degrees but do so gradually near the ends of the spectrum. The better amps (SS) with frequency ranges that are flat upto 100Kz and run well below 10Hz only might show a few degrees in the extremes of the audible bands. Well, taking a current tube amp from the AR stable, here are the specs: VSi60 Integrated Amplifier: POWER OUTPUT: 50 watts per channel continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 1.5% at 50 watts, .05% at 1 watt. FREQUENCY RESPONSE: (-3dB points at 1 watt) 1.0Hz to 80 kHz. Btw, not taking a top of the range amp but just a "lowly" integrated amp. Tube amps have improved tremendously over the years. Don't think we are still in our father's time.
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pagan
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Post by pagan on Jan 31, 2012 7:38:20 GMT
The phase shifts of tube amps and amps that have limited frequency response with cutoff points within the audible band can vary till 180 degrees but do so gradually near the ends of the spectrum. The better amps (SS) with frequency ranges that are flat upto 100Kz and run well below 10Hz only might show a few degrees in the extremes of the audible bands. Well, taking a current tube amp from the AR stable, here are the specs: VSi60 Integrated Amplifier: POWER OUTPUT: 50 watts per channel continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 1.5% at 50 watts, .05% at 1 watt. FREQUENCY RESPONSE: (-3dB points at 1 watt) 1.0Hz to 80 kHz. Btw, not taking a top of the range amp but just a "lowly" integrated amp. Tube amps have improved tremendously over the years. Don't think we are still in our father's time. You have to realize that that measurement was probably done into a 8 ohm resistive load. edit---- Just looked at it's spec's "OUTPUT TAPS: 8 ohms, 4 ohm" Speakers are not just a resistive load. allan
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XTRProf
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Post by XTRProf on Jan 31, 2012 8:21:22 GMT
You have to realize that that measurement was probably done into a 8 ohm resistive load. edit---- Just looked at it's spec's "OUTPUT TAPS: 8 ohms, 4 ohm" Speakers are not just a resistive load. Same for SS amps as well. What I'm trying to emphasise is that tube amps have also improved in the frequency domain to match the SS amps and in doing so also will reduce the phase shift based on what Frans was trying to depict.
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Post by Deleted on Jan 31, 2012 10:57:27 GMT
I was talking about the more affordable stuff such as Woo Audio
WA6: Headphones impedance : 8-600 Ohms Frequency response: 20 Hz - 30 KHz, -3dB Signal/Noise: 93 dB THD: <= 0.3%
WA22: Headphones impedance : 8-600 Ohms Frequency response: 8 Hz - 50 KHz, -3dB Output: 1500mw @32 ohms, 700mw @600 ohms Signal/Noise: 92 dB THD: <= 0.3%
acceptable specs for a transformer coupled design loaded with a resistive load.
Ofcourse there are far more expensive tube amp designs that have more than acceptable performance. Also there are SS amps that have considerable phase shifts in the audible extremes (often even on purpose) That's what I am trying to depict.
What one has to realise is phase shifts that determine the 'position' of an instrument are relative from R to L ear. Amps tend to have similar behaviour on the left and right channel so the difference between L and R which determines position is not influenced by the amp's phase (time) behaviour. Headphone drivers are more prone to show differences between L and R which determine positioning.
phase shifts(differences) between ground waves and harmonics are the ones that might trouble the sound reproduction. Ground waves and its harmonics that are 2 to several times higher can have a shifted phase relation IF the amp is rolled off and if the HP preforms less than optimal.
Dangers lie in blaming aspects of sound reproduction, that are not regularly adressed, and thus might/should/could possibly be responsible for the, so hard looked for, unexplicable things that refuse to become technically proven and might shed some light in the differences between subjectively found differences and technical provable differences.
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pagan
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Post by pagan on Jan 31, 2012 11:30:23 GMT
Ground waves and its harmonics that are 2 to several times higher can have a shifted phase relation IF the amp is rolled off and if the HP preforms less than optimal. s. Ground waves? Do you mean noise on the grounds, ground bounce? Allan
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Post by Deleted on Jan 31, 2012 12:22:22 GMT
The ground tone, the primary one. a bass note may have a ground wave of 40Hz for instance. 2nd harmonic is 80Hz, 3rd 120Hz, 4th 160Hz e.t.c. Most instruments have harmonics that decay in a certain way over time after the tone was made. How much and which harmonics are most prominent says something about how it sounds.
The ground wave always has the highest energy content and is the lowest tone. If you lower that one in level (when reproducing by a roll off on the lows for instance) the harmonics relatively are louder. These harmonics usually die out before the ground wave does and gives it it's 'attack'. So if (by roll off) the lowest ground wave is less the bass seems 'tighter' because the harmonics (which define the attack) are louder relatively. With a higher output resistance the bass (ground waves) are elevated the most so when comparing 120 Ohm output to 0 Ohm output with most headphones the 0 Ohm sounds 'tighter' because there is less lows (ground waves) and thus people shout. It is better damped ... damping factor story comes out again. There is some truth in it though (damping factor) but too much is blamed on it.
Amplifiers with rolled off lows therefore can sound 'tighter' for the same reason, less groundwave amplitude compared to the level of the harmonics which is not rolled off (too high already)
looking at squarewaves directly says something about frequency AND phase response.
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Post by Deleted on Jan 31, 2012 20:34:03 GMT
Unfortunately when you write sentences such as the one that I have just quoted from yourself based on especially/normally very technical matters of which I am sure that you know what you are talking about so I read with great interest what you have to say about most topics without necessarily understanding them, I do feel that sometimes the clarity of the exact detail that you are trying to explain becomes so engulfed in language that the whole point of whatever the message may or may not mean becomes complete and utter bollocks so that no-one knows what the hell you are going on about which can lead to many people on said forum becoming completely confused by the wordiness of your so called technical spoutings which become totally meaningless to us lesser mortals who are often referred to as subjectivists by people quite similar to yourself who knows what he's talking about but unfortunately everyone else wonders what the heck it is you're actually trying to say. Dutch is hard enough but Double Dutch is worse. Ground waves? Do you mean noise on the grounds, ground bounce?Yes, I totally agree that the aforesaid person from the Dutch way of life without mentioning too many names but is in fact a dude and does a lot of soldering does occasionally come out with some sentences that are truly mind boggling and strange to say the least because I'm also not always sure what the gentleman is always actually saying so the result of these posts is that I am left in the dark concerning what exactly the topic may or may not be about so therefore the whole point of reading these types of posts can become quite confusing to us subjectivists since perhaps the use of English is difficult for us to use since we do have a tendency to compare music to the taste of food and other such things with no proof that it really does taste at all because, in fact it is only music which of course bounces of walls floors ceilings and even window panes so that the reproduction chain is full of really difficult situations in each type of set up depending on where it was actually set up assuming that it may have been set up correctly in the first place. If you get me?
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Post by Deleted on Jan 31, 2012 21:05:28 GMT
the groundwave is a bad translation from Dutch. 'grondfrequentie' I should have translated as ground-frequency. I see frequencies as waves in general so hence the translation 'mixup' a groundwave is (amongst other things) the propagation of a radiowave close to the earth surface in the world of electronics/radio. It travels slower than the radiowaves higher in the air in case no-one is interested. a groundfrequency is the the first frequency where harmonics are multiples from. .... my bad. The complicated scentence was just that. feel free to ignore it or write a funny reply. If something is not understood or seems strange...simply ask, just like Allan did. Translations can sometimes be weird. Everyone that speaks/writes in more than one language is familiar with that concept. For the fun of it... translate something with (for example) google in another language (try Dutch and have a laugh trying to pronounce it), translate it back in the original language with another translation program and compare the result with the original text... great entertainment.
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Post by gommer on Jan 31, 2012 21:14:09 GMT
You guys are both absolutely stunningly funny today.
I wonder, did I understand Frans 'cause my mother tongue is Flemish (I refuse to say Dutch), or because I'm an engineer?
To Ian: you have to love the thoroughness in Frans' posts. To Frans: I certainly do!
Cheers guys, Marc
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Post by Deleted on Jan 31, 2012 21:48:45 GMT
Frans backyard; Alexs backyard; Brilliant!!!!! ;D ;D
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rowuk
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Post by rowuk on Jan 31, 2012 22:08:00 GMT
IF you get enjoyment out of 'reproduction of sound' you will need a range of headphones and perhaps 2 or 3 amps with quite different properties to suit the needs of the quality lovers. Those that only care about the essence of the music generally own/use but 1 or 2 headphones and couldn't care less about their source. I resemble that!
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Post by Deleted on Jan 31, 2012 22:23:07 GMT
Sorry Frans. I was just pulling your leg. (The one with the clog on) You do remarkably well in English and I couldn't get near it in your language. I'm too daft. If I tell the truth, I did actually understand what you were saying, but it just made a funny read. sorry!!
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Post by Deleted on Feb 1, 2012 6:44:15 GMT
You guys are both absolutely stunningly funny today. Cheers guys X 2 ;D ;D ;D
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Post by Deleted on Feb 1, 2012 8:31:12 GMT
Maybe if I limit the amount of info (a form of compression) I could restrict myself to 'Z-like' one-liners. ;D
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