Sound issue
in [UK Mac]
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From: gavsko on 24 Dec 2009 11:38 Back to my original problem... Yes the Jack is 3.5 and seems to fit OK ~/Library/Preferences/com.apple.systemsound.plist There is no file of this name in my system. Is that bad???!!!! Not all G4 quicksilvers (i.e the 733) have a sound card screwed to the motherboard (I think, but I may be talking rubbish here), if I remove the sound card from my 800 will it default to another built in sound system on the motherboard or just do nothing? Tried all the other suggestions and no improvement. looks like no Bing Crosby this christmas.
From: D.M. Procida on 24 Dec 2009 14:24 gavsko <gcrosswell(a)aol.com> wrote: > I run itunes from a G4 quicksilver through an amp to provide music for > the whole house. All the vocal sound now appears as if it is in the > background (for CDs aswell). I thought it may be the amp blowing a > channel but I tested it using a friend's machine and it's fine. Is the > headphone socket (from where the phonos run) or hardware damaged or > could it be (hopefully) a software issue? (10.4.11 OSX) iTunes, and iTunes plugins, can apply equalisation to the sound. Sometimes this can get set inadvertantly. I include in this the fancy-pants dynamic sound 'improvers' (like the latest iTunes Sound Expander). What's worse is that it can be possible to set these in more than one place, for example in iTunes *and* in the general system sound preferences; they will *both* take effect. I don't know what's available in Mac OX S on your particular machine but I do remember that in Mac OS 9 it was possible to set something like this in three different places (iTunes, the Control Panel, and somewhere else too) and the effect would be horrifically cumulative. Daniele
From: Rowland McDonnell on 24 Dec 2009 21:20 J. J. Lodder <nospam(a)de-ster.demon.nl> wrote: > Rowland McDonnell <real-address-in-sig(a)flur.bltigibbet.invalid> wrote: > > > J. J. Lodder <nospam(a)de-ster.demon.nl> wrote: > > > > > Rowland McDonnell <real-address-in-sig(a)flur.bltigibbet.invalid> wrote: > > > > > > > T i m <news(a)spaced.me.uk> wrote: > > > > > > > > > real-address-in-sig(a)flur.bltigibbet.invalid (Rowland McDonnell) wrote: > > > > > > > > > > >300Hz is a `typical highish voice tone' (I hope) > > > > > > > > > > > When I was with BT we talked of 'voice' paths being from 300Hz to > > > > > 3300Hz suggesting 300Hz was a pretty low voice tone (if we are > > > > > talking about the same things)? > > > > > > > > I've no idea what a `voice path' might be - but 3kHz is `overtone' > > > > territory for the human voice, not a fundamental. At least, not for > > > > anyone pitching their voice in the usual range. > > > > > > > > Hmm. > > > > > > > > "In telephony, narrowband is usually considered to cover frequencies > > > > 300-3400 Hz." > > > > > > > > Okay, so I dunno. 400Hz sounds pretty high pitched to me and > > > > telephone voices do seem to be missing the lower frequency part of > > > > the voice sounds, so I've thought for as far back as I can recall. > > > > Don't have a spectrum analyzer handy - if I did, I'd have a look. > > > > > > For the stereo signal 400 Hz is the roll-over point. > > > > What roll-over point? > > <http://en.wikipedia.org/wiki/Low-pass_filter> But that does nothing to answer my question. > > > below that the S-component drops with the usual 6 dB/octave. > > > > S-component? > > Stereo component? Uhuh. > M = L + R > S = L - R > > L = M + S > R = M - S > (insert /2 where wanted) > > So, supposing you start with L and R signals, > from a stereo microphone for example. > Before publishing on disk one would > 1) transform L and R to M and S > Feed S through a high-pass filter, > roll-off 6 dB/oct below 400 Hz, to obtain S'. Ah! *THAT* roll-over point - right, now you've explained what the hell you're talking about. > 2) recombine M and S' to L' and R' Why? > This has the effect of making low frequencies mono only. > (to be cut horizontally into the vinyl) But why? > No real loss, metre waves > don't carry directional information, > given the size of an average room. Why do that at all? > That's also why there is little loss > in systems that use a single sub-wooofer. What do you mean by that? > > > Bass singers are therefore hardly affected, > > > > Er? > > They produce no significant power below 400 Hz. > Even if they can go lower > almost all the power is in the overtones You made this statement: "For the stereo signal 400 Hz is the roll-over point. below that the S-component drops with the usual 6 dB/octave. Bass singers are therefore hardly affected," Your explanation is no explanation at all. Rowland. -- Remove the animal for email address: rowland.mcdonnell(a)dog.physics.org Sorry - the spam got to me http://www.mag-uk.org http://www.bmf.co.uk UK biker? Join MAG and the BMF and stop the Eurocrats banning biking
From: Rowland McDonnell on 24 Dec 2009 21:20 gavsko <gcrosswell(a)aol.com> wrote: > Back to my original problem... > > Yes the Jack is 3.5 and seems to fit OK `Seems' - umm... `seems' isn't very good. I'd try a different lead if I were you. What if you try plugging headphones in directly? > ~/Library/Preferences/com.apple.systemsound.plist > > There is no file of this name in my system. Is that bad???!!!! Dunno - I'm using 10.6.2 here. When I refer to ~/, I mean `Your home folder', so ~/Library/Preferences/ means your Library folder as a user. Any prefs at all with `sound' in the name? > Not all G4 quicksilvers (i.e the 733) have a sound card screwed to the > motherboard (I think, but I may be talking rubbish here), if I remove > the sound card from my 800 will it default to another built in sound > system on the motherboard or just do nothing? I don't know. I've not heard of any Macs with Apple-supplied sound cards fitted as standard - perhaps that's just because I'm iggerent. > Tried all the other suggestions and no improvement. > > looks like no Bing Crosby this christmas. The fault makes no sense at all. It's just /got/ to be something `round the edges' that can be fixed, from what you report. Or so I think. Rowland. -- Remove the animal for email address: rowland.mcdonnell(a)dog.physics.org Sorry - the spam got to me http://www.mag-uk.org http://www.bmf.co.uk UK biker? Join MAG and the BMF and stop the Eurocrats banning biking
From: Rowland McDonnell on 24 Dec 2009 21:20
"Graham J" <graham(a)invalid> wrote: > "Rowland McDonnell" <real-address-in-sig(a)flur.bltigibbet.invalid> wrote in > message > news:1jb6jkf.11xh69a1b8w1e5N%real-address-in-sig(a)flur.bltigibbet.invalid... > >T i m <news(a)spaced.me.uk> wrote: > > > >> real-address-in-sig(a)flur.bltigibbet.invalid (Rowland McDonnell) wrote: > >> > >> >300Hz is a `typical highish voice tone' (I hope) > >> > > >> When I was with BT we talked of 'voice' paths being from 300Hz to > >> 3300Hz suggesting 300Hz was a pretty low voice tone (if we are talking > >> about the same things)? > > > > I've no idea what a `voice path' might be - but 3kHz is `overtone' > > territory for the human voice, not a fundamental. At least, not for > > anyone pitching their voice in the usual range. > > > > Hmm. > > > > "In telephony, narrowband is usually considered to cover frequencies > > 300-3400 Hz." > > > > Okay, so I dunno. 400Hz sounds pretty high pitched to me and telephone > > voices do seem to be missing the lower frequency part of the voice > > sounds, so I've thought for as far back as I can recall. Don't have a > > spectrum analyzer handy - if I did, I'd have a look. > > I think the voice frequencies that make for intelligibility exist in the > 300Hz to 3kHz range. Below 300 Hz if the loss is 6dB per octave the > attenuation of a typically male voice is not all that significant. I > suspect that below about 100Hz the attenuation is much more than 6dB per > octave, since typical telephony paths traditionally used transformers and > similarly constructed transducers. Righto. > For music of course very few people appreciate anything over about 15kHz > (and those that do complain bitterly about TV line whistle). Sounds like me, that does. I remember having people sneer at me claiming to be able to hear over 20kHz in my early 20s - did they ever stop to wonder why I whinged about the telly whine that none of them ever seemed to notice? Or how come I was so precise about the different upper limits on the two ears? Yes of course I'd had a play with the test gear I ran into in the lab... Dunno what my hearing works at these days. I'm some two decades older. Rowland. -- Remove the animal for email address: rowland.mcdonnell(a)dog.physics.org Sorry - the spam got to me http://www.mag-uk.org http://www.bmf.co.uk UK biker? Join MAG and the BMF and stop the Eurocrats banning biking |