MP3 Fidelity Results

Spent a few hours last night at Mike’s house listening to the MP3 fidelity test discs I burned the other day. The discs included these tracks:

Coltrane – Resolution (the Michael Cuscuna – produced version of A Love Supreme)
Alban Berg: Three Pieces for Orchestra, Ostinato (on RCA Living Presence)
Rob Wasserman – Angel Eyes (cello / vocal duet – superb recording)
Klip – Dyslexiana
Theresa Anderson – Summertime (my fave female vocals test and fave cover of this song)
Gerry Hemingway – Endpiece 1 (from Special Detail)
Tim Buckley – Hullucinations (from Live Dreamletter)

We did not get around to listening to all four versions of all seven pieces. The system we used was:

Audio Alchemy CD transport with DTI Pro jitter reduction
Audible Illusions Modulus 20 pre-amp (heavily modified)
Muse 100 amplifier
NHT 3.3 speakers

System value approximately $20,000

I’m still trying to figure out what we learned from all of this. First of all, I can unambiguously say that I have never heard MP3s sound this good in my life. Second, this is the first time I’ve ever been able to distinguish between 256kbps MP3 and the original source material. However, I also learned how much the mind plays tricks on you in tests like this, and hence why audio mags often avoid them. The only valid test is really to live with the material, doing what you do normally, whether that be sitting down and doing concentrated listening or playing it in the background while going about your business. In other words, if we listened to these tracks over and over again, and if we lived with them and subsumed their presence into the subconscious, we would be able to discern additional differences we didn’t notice yesterday.

I also have to say that Mike has a lifetime of intensive experience and training in audiophile listening environments, and in building hifi audio equipment. I care a lot about fidelity, but don’t have ears as well trained as his. He was able to discern more differences than I was.

Mike also pointed out some problems with the methodology of my experiment. Because each track can last 5-10 minutes, it’s extremely difficult if not impossible to make meaningful comparison notes without a standard of reference. IOW, I wanted for us to try and pick out the reference track blind, while he felt it would be more meaningful to know in advance which one was the uncompressed WAV, so we could compare the other bitrates to it. His point made more sense after we listened blind for a while – your mind really does play tricks on you. For example, you might hear more air in a cymbal splash in one track, but you could be unsure whether that “air” is in the reference (a good thing) or an artifact of the encoding process (a bad thing). So in the end we did most of our listening with knowledge of which track was the WAV reference.

Neither of us had any difficulty picking out the 160kbps tracks, which was disappointing knowledge for me, as I’ve encoded tons of music at 160kbps. From here on in, I’ll use 160 only for crappy old recordings, 192kbps for average stuff, 256kbps for stuff I really love or that’s really well recorded, and 320kbps for those amazing gems that are stellar both as music and as recordings.

Mike is going even higher. His argument is that disk space is just so cheap now, there’s no point in compressing at all. Why risk it? It’s interesting because this is the same argument I made in the intro to my MP3 book – that the only reason we even talk about compression is because storage is too expensive and the internet is slow. But think about it – 40GB drives are under $100. It’s possible to fit around 60-70 albums on a 40GB drive in uncompressed WAV format. That’s about $1.50 per album in storage space. If you care enough about your music to have a system like his but you still want the flexibility of soft storage for your collection, why compress at all? Then you just build an array of 10 or so IDE drives to house your collection, which would be like spending a grand on an important new stereo component – worth it.

I counter that by saying that the difference b/w 256kbps and WAV is so incredibly subtle, and 320kbps would be virtually indistinguishable in every important way. You still get around 4x compression at 320kbps, and you have the advantage of ID3 tags. Why not take advantage of it?

I could tell there was a difference between the 256 and the WAV in the Wasserman duet/vocal, but had trouble putting my finger on the difference. Mike nailed it down, and had me focus on the spatial relationship or distance between the vocalist near the middle of the room and the cello in the rear left of the room. At 256kbps, there is a sort of “veil” that enshrouds the vocals, and ties it spatially to the cellist in the rear left. It’s subtle, but he’s right – the spatial distinction between them is just not as pronounced at 256kbps as it is with the WAV. But the fact that it had to be pointed out to me, and that I had to concentrate to find the difference even then, tells me that this is a difference I can live with, even if he feels he can’t.

However, the same effect at 160kbps is atrocious. It sounds like there’s a blanket thrown over the whole production – like you’re listening through a thin layer of gauze that sort of erases or diminishes the space between musicians. However, it requires a system better than most people own or have even heard in their lives to reveal some of these differences. On a standard Japanese consumer stereo, 160 might be adequate for most people.

My problem is that I haven’t followed my own advice. I have professed that people’s MP3 collections would eventually migrate to their home stereos, and have warned that they shouldn’t trust their computer sound systems to tell the whole story. Nevertheless, I’ve encoded almost everything at 160kbps, and now have a collection that will translate to the home stereo with less than stellar results. Hrmmm…

Two-armed typing, MP3 fidelity testing

The arm is slowly healing. Have discovered that if I take off the sling I can use the right arm to hoist the left onto the laptop keyboard, where it receives enough support to allow me to type two-handed. I can’t do it for a long time, but it will help me dig out of the backlog and start getting productive again. One-handed typing is NOT 50% of two-handed typing, because you have to move your arm back and forth over the keyboard and have to look at all the keys. Two-handed is about four or five times faster for me.

Mike and I have been talking about finally coming to an unambiguous conclusion about optimum MP3 bitrates – we want to find the rate at which MP3 is indistinguishable from the source CD. Neither of us are tolerant of MP3 compression artifacts and neither of us care about keeping files small enough to trade over the net – we just want as much compression as we can get without compromising a drop of fidelity.

I’ve done some experiments before, but we’re going to do this one right. He brought over some of his best hi-fi selections, including some of the RCA Living Presence stuff. I contributed three of my own favorite fidelity test tracks, and used my little TestEnc script to encode six sample tracks at a variety of bitrates with the lame encoder. Then I burned those tracks back to audio CD. This returns them to PCM, but with the compression losses now built in.

The weak link in the chain is Be’s built-in decoder which I’m forced to use to translate from MP3 back to PCM when burning the disc. It’s based on blade, which is OK, but definitely not the best, and certainly not what I would use for a test like this given my druthers. If I suspect it’s getting in the way, I may have to do this in Windows with CDex or something that lets me choose the decoder.

Before burning, I randomized the track orders and printed out a key listing all the actual bitrates. Folded this up and sealed it. I also printed out track lists w/o bitrates and we’ll use those to write notes about our impressions. Tonight I’ll take these to his house and listen to them on his system, skipping around between the track variations and making notes. We’ll see how the notes compare to the key page.

OK Soda, Baffler, Hermenaut

Anyone remember this soda? It appeared on the market for about six months in the mid 90s and then promptly disappeared. Today I saw a reference to it on my favorite news and culture site Plastic.com:

http://www.plastic.com/article.pl?sid=01/06/29/1729221

Only to discover that the reference is due to the recent appearance of an article by my old Boston friend Josh Glenn in the Baffler:

http://www.thebaffler.com/glenn.html

Way to go Josh – you got plasticized! Very good article, too. But The Baffler competes with Glenn’s own magazine Hermenaut (www.Hermenaut.com), which, incidentally, used to be hosted at my site birdhouse.org. Sleeping with the enemy again Josh?

Tow truck

CycleTow just came and hauled away my bike to evaluate whether it’s totalled or repairable. Seeing it in the light of day, it’s more messed up than I thought. The subframe is tweaked, which may tip the scales toward totalled. So sad to see it being hauled off like that. Like watching a best buddy move away or something.

Such a beautiful morning… I should be going for a ride. Sigh.

a blur

Have spent the last five days mostly on the couch, in a blur of vicodin and movie rentals. Here’s what I’ve seen in the past few days:

Alfaville – Godard
The Harder They Come – Jimmy Cliff
Wonder Boys
Reefer Madness
Bamboozled
Twisted Obsession
Discrete Charm of the Bourgeoisie – Bunuel
One Day in September – 1972 Olympic terrorists
The Eyes of Tammy Faye
The Ladies Man – ugh

DVDs from the Criterion collection are so great. The Bunuel documentary on Discrete Charm was fantastic, as was the commentary on Harder They Come.

Getting so frustrated not being able to do anything. Even small things like washing the dishes are minor triumphs. Last night I “escaped” from my sling somehow and woke up wiyh my arm above my head somehow. No wonder it’s so sore now. Will have to cinch myself in tighter tonight. I’m so ready for this whole thing to be over and have my life back, but there’s much more pennance to pay.

Have been reading developer materials on groove.net. Much learning to do before I can be useful to them.

Bahjinagh

Bahjinagh is the Persian word for “husbands of sisters,” like Sharoq, Steve, and myself are vis a vis Ellen, Lisa, and Amy. In Iran, it’s a special family unit. In Persian legend, Bahjinagh are capable of overthrowing kings!

Shah told me about this when I was in Bothell, and I just found the note where I wrote it down. Wanted to post it so I’ll remember.

Paying the piper

It finally happened — I pushed it too far on the bike and bought the farm. Mike and i took a ride out Redwood Rd. to go to a gear shop in Castro Valley. Had a great Mexican lunch. On way back, we were really flying – felt so good to be on familiar twisties again. Was thinking how nice it is that the bike is finally all broken in and that I’ve found my zen with it.

Was in a decreasing radius left-hander doing about 45 when the turn suddenly got much tighter. Cranked it over harder, but started to freak out when I realized I was getting too close to a drainage ditch at edge of road. Because I couldn’t lean any farther with confidence, I should have been pushing down sideways on the bars to eek out a few more ounces of angle. Instead, I panicked and tapped the front brake. That’s all it took to stand it up, which sent me straight into the ditch.

Rambled through the ditch for a few feet, then the front tire bounced out and caused the bike to catch air and sail back toward the road. Bike came down nose first at an angle and i went head first over the handlebars. Had a moment to think about how to roll. Landed on my left shoulder and elbow, plus side of helmet. The bike came crashing down behind me with an evil, expensive sounding noise.

I immediately jumped to my feet and out of the road, then realized the bike was at the end of a blind curve and liable to be run into by a car or to become an obstacle for another bike. I went to it and grabbed the handlebars and tried to lift it. As soon as I pulled, I felt a rippling run through my upper left arm and something felt like it was out of place. The pain was pretty intense and I sat down on the side of the road. Everything was chaos. Realized later that I probably started the arm fracture in the crash but actually broke it trying to lift the bike.

Mike had been right in front of me, and though I knew he couldn’t see it happen, I knew he would turn around soon and come find me. Minutes later, another biker stopped to help me out. He was able to get my bike out of the road and to a pullout on the other side. It looked pretty messed up. Another guy showed up, then another. Some bicyclists were there. I started to come out of shock and was sweating like a pig. One guy had some medical experience and did some coherence and visual tests – I was fine, or at least didn’t have a concussion. But the pain in my upper arm was really starting to kick in. A bicyclist gave me 800mg of ibuprofen. Had a few sips of water.

Somewhere in the middle of all this someone rode down to the ranger station to call the paramedics. They arrived 15 minutes later followed by the CHP. More questions and more tests, then climbed into the back of the ambulance — first ambulance ride. CHP wrote up an incident report.

Went to Alta Bates emergency room where the interminable waiting began. Was in there for hours. Finally took x-rays. Big fracture running diagonally across my left humerus. Amazingly though, everything is in tact and in alignment. Doc predicts it will heal nicely but will take time.

Amy and Mike showed up around 10:30. Mike had taken care of having the bike towed down off the mtn. Amy had been teaching and saw Mike arrive with tow truck. She was worried sick. She has always been so worried for me and this is the last thing I wanted to put her through. But she was a trooper.

Finally got sent home with a splint and sling, a bottle of vicodin, and a prescription. Had fertility duty, then slept fitfully. Today it’s all still sinking in, what it means to be pattially disabled for the next 8 weeks, what I did wrong, how it could have been avoided.. Every little thing is a goddam hassle now (like buttoning my pants), and I need to start making money. Life is so weird. Went to see orthopedist and he said I wouldn’t need a full cast — just the sling and another x-ray in 12 days.

Pretty ironic that I just finished a 3500 mile ride without incident, then all this happens on a 50 mile afternoon jaunt. Helmet will probably have to be replaced. Jacket is deeply gouged but still viable. Aerostitch looks fine. Protective gear saved my life today. Head would have been smashed open without the helmet. Bike will need quite a bit of work and I can’t afford that until I’m working again. I won’t be riding for a while. May even make a bigger decision about riding. Can I trust myself to reign it in?

I’ve typed this out one-handed, hunt and peck. It has taken a long time. I’ll have to get used to it.

Time passes swiftly by

Let me respectfully remind you,
Life and death
Are of supreme importance.
Time passes swiftly by
And opportunity is lost.
Each of us should strive to awaken.
Awaken!
Take heed:
Do not squander your life.

– The Evening Gatha

Turning Point

BYTE ran a piece I wrote two weeks ago:

Turning Point for Be, Users

about the BeOS situation as it stands… just how bad it is, who should keep using and why, etc. Ignited quite a firestorm on BeNews, but most people didn’t begrudge my position… most agreed with it. A few flames, easily extinguished. The weird thing was that I got messages from old Be engineers and employees… people I hadn’t heard from for quite a while writing to commiserate, and to remember what it used to be like. Interesting that they’re still following Be after all this time, long after they’ve moved on personally. BeOS gets under you skin that way. People are never the same after they start using. Was kind of nice reconnecting with an older segment of the community.

Between that and the recent “Adamation leaves the BeOS scene” announcement I had to write, I feel like a Benedict Arnold. Except that I’m not a traitor – I’ve done everything in my power to keep things alive. Why there were never dozens of journalists on the BeOS beat is still a mystery to me. I shouldn’t have been alone.

Anyway, it just amazes me that there are people today who think I’m being unfairly harsh on Be. “They’re going through hard times. You shouldn’t be so callous.”

For godssake people, open your eyes.