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Ksolem
Trad climber
Monrovia, California
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Roy, my experience with electric motors is that they don't degrade slowly over time. What you'll get is variable speed followed by failure, or failure to start. Then when it does start it will drag and the speed will jump around. A lot of times it will act up for a bit and then sort itself out. In any case a loss of speed, but still constant, is uncommon.
Of course if you check it with with one of the strobe cards you'll know, even if you can't adjust it.
Edit: Now that I think about it a loose belt will not slip at an constant rate either, so if that's the problem you should hear significant wow in the pitch, not just time. Hmmm..
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ionlyski
Trad climber
Polebridge, Montana
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That room was designed around the speakers and tuned four times a year using a TEF analyzer at many locations in the room.
Doesn't matter Kris how many times a room was "tuned" EQed I guess you're saying. Two sources of low end (actually 4 in this case with the 15's) cannot be corrected, electronically or otherwise. Its a simple problem of time; a smear if you will and low frequency exacerbates the problem.The solution is to try and keep low frequency out of the stereo imaging. Keep the stereo imaging at least above 80hz (some modern thinking even higher) in a frequency range that is actually directional anyway? (why try to pan low end, a non-directional range)
Power Alley is a very common and long understood problem, merely accepted until recent solutions, especially for multiple loudspeakers (sources) including sub sonic cardioid methods and other steering methods, like incremental delay of source units. You may resist accepting the notion that current live sound events are leading the way to the highest fidelity possible. No way the audio dynamics, frequency response and moving air can be reproduced or mastered to equal what is happening in the very high end tour market. Not referring to a Rolling Stones concert:)
Much cheers to you.
Arne
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Ksolem
Trad climber
Monrovia, California
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^^^^Now we're talkin'...
Arne, I understand the non-directional aspect of bass. My system at home is much more hi-fi than the big old studio monitors, and I have a single point sub crossed over at 80hz. But we managed the low end in the studio quite well. Yes the regular tuning was eq, but the room itself was constantly tested as it was built, and we continued to play with it for years after that. Some of it was accepted practice at the time; compression ceiling, no parallel walls, the usual bass trapping, etc. Some of it was our own ideas. Anyway we had a lot of fun with it, and it was a very exciting listening environment. One thing I enjoyed, which has nothing to do with the subject, was having those very inefficient mains over-powered enough that the rig was idling at a good listening level.
Are you in live sound? I knew that wasn’t for me. Too much happening all at once. I sat with a few of the best at one time or another. Ed Greene comes to mind. He sat at the console in his own bubble of calm serenity surrounded by what looked to me like chaos. Typically the work in a mastering studio moves along at a nicely controlled pace, not so many surprises 😉
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Ksolem
Trad climber
Monrovia, California
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A lot of that, like the sheet-rock with air between, is for soundproofing. Works even better if the two layers of sheet-rock are different thicknesses so they don't resonate at a common frequency. That's how they do the glass between the control room and live room in studios. They also set the panes so they're not parallel.
I've never heard of this diaphragm thing, sealing the room with plastic, but that's happening to me a lot on this thread :-)
Sounds like he used a digitally controlled eq. You can have presets. I used one in the mastering studio. I had one preset just for the rappers. I'd usually get about two minutes to listen flat before they demanded more bass, but I knew if I put all that extra bass on the master then consumer speakers wouldn't handle it and they'd be mad at me. So I'd hit the preset and send a bunch more bass to the monitors than to the master. I basically quit listening and flew on instruments. They'd take a ref disc and roll with it, play it at their crib, and at the studio. Then they'd come back and tell me how they were right to push for all that extra bass.
Did you hear about the record producer who got hit by a train? He never heard it coming...
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ionlyski
Trad climber
Polebridge, Montana
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Yeah Kris, live audio. Started in the studio switched to live 30 years ago now the only thing left that interests me is outdoor festival stuff at the tour level, God's room right? No reflective energies to try to predict.
I've enjoyed your mastering equipment and experience topics, vinyl cutting gear all that cool stuff. My "mastering work" was really just focused on doing the dreaded transfer to digital CD 44.1 16 bit red book stuff. Mixing all the way to two track tape, then EQ to two track digital and burning to CD back in about 1987 I think.
Arne
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Ksolem
Trad climber
Monrovia, California
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I know this thread is of little interest to the majority here, but a few of us like it and it beats the hell out of politics.
Having had the time to actually think this through I have a question for Arne.
Regarding studio recordings, 90% of the music I listened to on those big Tannoy 215's: Aside from effects common in club mixes and the like, any producer/mixing engineer worth their salt sets the bass dead center. This makes all this stuff about bass in the stereo image mute, yes?
The TEF (time-energy-frequency) analyzer plays pink noise, cuts it off instantly, and shows you the room decay across the spectrum. We made adjustments in the room first, and eq second, accordingly. Pink noise is uncorrelated, so again the business of imaging the low frequencies is not relevant.
FWIW the Tannoy's were not crossed over between the two 15's even though one was a low frequency driver and the other, the one with the hi freq horn in the center, was a midrange driver. Those speakers have a crossover for the 15's which can be bypassed. They worked much better in that mode. Let the drivers sort it out, no phasing in the crossover band. I'm not sure how that would work in a cabinet that is not ported.
My comment about bass being about moving air is valid whether the layout is a single point sub or a stereo array. Size seems to matter, within reason. Subwoofers with small driver are simply tuned ports.
I'm not trying to make a specious argument, the points you have made really got me to thinking. Too bad we're not in the same area, it would be fun to do some listening together.
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Ksolem
Trad climber
Monrovia, California
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We cross posted.
In 1987 that transfer to 44.1 16 bit was truly a nightmare.
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ionlyski
Trad climber
Polebridge, Montana
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Kris,
Wish I could make it down to the Bridwell Memorial. We could stay up all night talking about audio and in this case, competing sources, whether they are caused directly by speaker components stepping on each other's toes or by high energy room reflections, disturbing the math and complex prediction of the waves interfering instead of summing together like well behaved waves.
I am due however to get back down to Cali probably solo in the van and find some good campfires. Never been to the Needles either.
Yeah, with the transfer from tape to 44.1 the best you could do was try to remove some upper mid-range brightness to try and simulate analog. Wasn't horrible but not great either. Now I kind of miss it in a world of MP3 I try hard to avoid but permeates our entire listening process like an infectious disease. I miss real telephones too.
Arne
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Tarbuster
climber
right here, right now
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Here's some low-grade borderline audiophile gear I've been listening to for over 30 years:
Note the 10 inch 33 1/3 jazz collection from the 50s!
(... and don't ask me about that floating turntable shelf: I don't want to talk about that right now, ha!)
Canton Quinto 510 present nice clarity, a well-organized soundstage and very tactile imaging: good for enjoying music featuring acoustic instruments and female vocals.
a/d/s L8e are nothing special, but for rock 'n roll I play them in parallel with the Canton.
Question: I lost a channel on my original NAD amp (Hafler was an upgrade anyhow, in its handling/expression of mid range), and some gearheads told me that running speakers with different ohm values in parallel could do that (cook one channel of a power amp), and a speaker selector with a protection circuit was recommended, which I now have in-line (Adcom). I don't run the protection when just listening to one pair. Does that sound right: I.e. running that extra circuitry to protect my amp when running different speakers in parallel?
[a/d/s/ are rated at 4 ohm, while the Canton say 4-8 ohm, and I think the audio guys said it even has as much to do with the mismatch of all the drivers themselves? I don't know how crossovers deal with all that stuff. I just listen to music.]
Question: you'll note those Canton monitors are rated all the way up to 30,000 Hz. They certainly are on the bright side, which I like. Yet I've heard many times that the human ear can only discern up to 20,000 Hz?
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G_Gnome
Trad climber
Cali
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Vinyl is about a different quality of sound than you normally get with a digital recording. When CDs were first introduced no one really understood how to get the best sound quality out of them. Also at 44khz and 16 bits there isn't enough bandwidth to reproduce sound as well as vinyl can. Now days, if someone bothers to put the effort in they can produce excellent sound at the higher resolutions available digitally.
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Binks
climber
Uranus
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My setup:
Basic setup:
Vanatoo T1 powered speakers (also have a built in DAC)
Martin Logan Dynamo 30 sub
Little Dot MK3 tube amp (used as phono preamp, and headphone amp)
Inputs:
Turntable: Project 1Xpression III with Ortofon blue cartridge/stylus
CD player: Denon DVD-2910 (plays SACD format in addition to regular CDs), digital out directly to Vanatoo T1 internal DAC
Bluetooth: Avantree Roxa
Pono player (usually run it thru the Little Dot MK 3, shines for high def files)
Chromecast Audio (I have two of these)
1) using optical digital out directly to Vanatoo speakers, which have an internal DAC
2) using optical digial out to JDS labs OL DAC, run to the Little Dot MK3, because, well, it sounds really good and sometimes I prefer the sound thru the amp
Headphones:
I have several, but my favorites are Sennheiser HD 600s, which I listen to either thru the LIttle Dot MK3 or using the balanced outputs directly from the Pono player.
The Little Dot MK3 tube amp is the genie in the bottle, or it's tubes have the genii, depending on how you look at it. I love it, it's like magic. Not everything benefits, that's why I can opt for pure digital.
I consider this a budget audiophile setup... and challenge anyone to come up with something that sounds this good for less money.
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Tarbuster
climber
right here, right now
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Again:
For me, listening to vinyl is more of a run what you've brung situation. I have a record collection and I'm not interested in parting with it. Those 25 10 inch 33 1/3 jazz albums may not even be available in digital format.
I'd also say there's a tactile difference in listening to vinyl (in the ear, not in the hand), and from a collector's point of view, the gatefold sleeves and associated artwork are pretty nice.
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Tobia
Social climber
Denial
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May 11, 2018 - 06:30am PT
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♪
Vinyl. I have lp's I started collecting when I was a 14 or 15. Like Tarbuster, some are out of print and were never digitized. I can't remember when I lost my turntable, I believe my Lab chewed it up. All my sound equipment is analog. I had to quit buying CD's due to budget restraints, but occasionally will bite the dust. I think Jingy taught me to look for AAD SPARS Code on a CD, since it is a digitized version of the analog tapes.
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Tobia
Social climber
Denial
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May 11, 2018 - 08:04am PT
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Speakers, all depends on your ear. Buy what sounds good to you, not what someone else prefers.
I like my Klipsch speaker system w/ sub-woofer. Unfortunately the Klipsch family sold out to Audiovox in 2011 and that may have changed things.
I wish I could buy a turntable, it used to be the tonearm, cartridge and stylus that made the difference in sound quality and not the turntable price.
I had a Technics SL-1200, but it was lost to my dog.
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Ksolem
Trad climber
Monrovia, California
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May 11, 2018 - 11:30am PT
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Digital audio cares about one thing only: How loud am I now. On a CD, that question is asked 44,100 times per second for each stereo channel. That is the sampling rate, call it the horizontal axis. The answer to the question is recorded as a 16 bit number. This offers a vertical axis of resolution of −32,768 to 32,767. So comparatively the resolution of the vertical axis far exceeds that of the horizontal. To complicate the topic of resolution (sound quality) further, while we can double the vertical axis resolution with the addition on one bit, we can only double the horizontal axis by doubling the number of samples.
So, what’s wrong with 44.1? Let’s say we’re trying to record a 10,000 cycle tone (10 kHz.) But we can only ask “how loud am I now” 4.41 times per cycle. If we design our analog to digital converter to interpolate that as a sine wave we have it nailed. A faithful recording of a 10 kHz tone. Now let’s take our tone and add a simple harmonic distortion, the sort of thing which gives different sounds their colors. Our harmonic will be in the form of a small dent in the peak of the sine wave. Oh dear, we hear it before the conversion but not after. Since our 10kHz tone and our 4.41 samples don’t have an integer relationship every so often a sample will be taken on or within the harmonic distortion. Most systems encoding at 44.1kHz interpolate out this “error.”
As the frequencies in the music get higher we have fewer opportunities to measure and record the waveforms accurately. Our example above was a simple sine wave. In music, of course, we have an endless complexity of sound modulation happening all at once. Higher frequencies interacting with lower ones to create harmonics across the spectrum. Our sample rate is dreadfully slow.
Knowing this, go listen to a classical CD, a natural sound made by real instruments. Pay attention to the midrange up to the higher frequencies. The high notes on a piano, or those played by a flute, or a cymbal crash are all made of the same soup. We largely recognize them by their dynamic envelope, not by their unique tone. The formants of their sounds are washed away by the lack of information to define them.
Finally, there’s this inconvenience called the Nyquist principal. A sampling system cannot record events that exceed one half of the sampling rate. What occurs is called aliasing. When the wagon wheels in an old western appear to be spinning backward it is because the spokes are faster than the frame rate of the camera, another example of a sampling rate. But what looks cool in an old movie does not sound cool if we let it happen in our music recording.
Nyquist demands that we filter out all frequencies below 22.05kHz. Easy enough, right? We can’t hear that high anyway… But the filter design is the trick. A “brick wall” at 22kHz will create all sorts of problems in the audio passing through below; ringing, phase shift, etc. So, our filter must be more gradual. But now we are cutting into frequencies which matter. I could go on about how these frequencies we can barely detect change the sounds below them by creating harmonics.
A vinyl record, well produced, mastered and pressed – in good condition on a turntable up to the task – is free of these problems. I just came into a Leonard Bernstein / NY Philharmonic record produced by Columbia Masterworks. Still in the factory wrap. Twice, with reverence, I’ve played this disc. I have never heard any classical recording on a CD which even comes close. This is what keeps me, and many others like myself chasing down vinyl records, tweaking turntables, and enjoying the process which many see as inconvenient and expensive. And it’s fleeting. The records are delicate. Most of my favorites are like a bottle of fine wine, they only come out on special occasions.
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Tarbuster
climber
right here, right now
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May 11, 2018 - 11:54am PT
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Nice exposition there, Kris: thanks! I've always said there is a tactile difference in listening to vinyl.
And then this:
Nyquist demands that we filter out all frequencies below 22.05kHz. Easy enough, right? We can’t hear that high anyway
So to my post just up thread:
Question: you'll note those Canton monitors are rated all the way up to 30,000 Hz. They certainly are on the bright side, which I like. Yet I've heard many times that the human ear can only discern up to 20,000 Hz
So what's the reason for the 30kHz rating?
Did you basically just describe it?
I could go on about how these frequencies we can barely detect change the sounds below them by creating harmonics.
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phylp
Trad climber
Upland, CA
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May 11, 2018 - 12:00pm PT
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Del Cross, I think for the majority, it’s about the quality of the sound. When people would ask my husband about this, he would sit them in the “sweet spot” on the couch in his listening room and play them the same cut from Kind of Blue, one on vinyl and one on CD. Everyone could hear the difference.
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Ksolem
Trad climber
Monrovia, California
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May 11, 2018 - 12:57pm PT
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Tar,
My comment about frequencies we can barely detect influencing the sound of those below them was pointed at frequencies we lose due to the mandatory filtering for Nyquist. 16-20 kHz. Most people don't hear those very well, but they can hear their effects down through the spectrum if they spend some time listening.
Your speakers going up to 30k is unusual. But then they don't give the other half of the info you need to define the specification. Frequency response is defined by frequency and level. I would be very impressed indeed if it said "Frequency response: 36-30000 Hz +/- 2 dB." On the other hand if the speaker will reproduce 30k clearly, even if it's down 10dB by then, they ought to perform better than most at 20k.
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phylp
Trad climber
Upland, CA
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May 11, 2018 - 02:22pm PT
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I personally am referring to the emotional impact, the sense of how beautiful it is, etc. I couldn't speak to the technical side. But I think Kris has expanded at length in another thread about the technical differences between analog and digital recordings.
On a related note, I just read a long article in the LA Times about how the director Christopher Nolan has invested a lot of time and money into restoring a 70mm film version of Stanley Kubrick's 2001 A Space Odyssey. In the article he goes on about how different, and beautiful the film version is. It's going to be released in some theaters nationwide.
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