March
March 8
A GOOD GROUND, ESSENTIAL TO GOOD BASS--REALLY!
This place has had a chronic problem with line voltage sags under load. It was not uncommon for the voltage at the main service panel to drop below 90 volts when Bass Pig was on the rampage with heavy bass. When the QSC amplifiers would get past "signal present", the house lights would dim quite a bit. That dimming was enough to be noticed on some of my YouTube videos.
Since last year, when I was tracking down sources of sagging voltage problems in the wiring to the racks, I discovered that the neutral line was being pushed around quite a bit when loads were not perfectly balanced across 240 volt lines.
We have also, on occasion, had some problems with losing one leg of the 240, due to poor contacts on a meter junction box outside that's not being used for a meter. Well a few days ago, the power went out on that leg when I switched on my Sony video monitor at my editing workstation. The UPS took over and the continuous beeping told me that power was out to at least that circuit.
I investigated, and found that a sliding bypass switch in the meter box had burned up. So the next day, I went to Home Depot and bought some thick pieces of steel. I fabricated a jumper to take the place of a nonexistent meter, so that the bypass switch would not have to carry 200 amps. That fixed that problem.
While I was there, my curiosity about the mushy neutral line caused me to inspect the neutral line in the box. The part of the panel that I wired had 3/0 AWG wire as thick as your thumb for all three lines. But the external wiring, done by a state-licensed electrician, had 2 AWG mains wiring and 4 AWG ground wire, going 35' through an underground conduit to a pole with the electric meter on it. And that ground wire looks like it had been heated up enough to discolor the copper. No surprise, this wire was probably dropping 18 volts over it's 35' length.
Seeing as this was likely a big part of my sagging line voltages, I used some old 4 AWG aluminum cable, which had two conductors, wrapped by a ground conductor, and cut a length to fit, stripped back the insulation and tied all three conductors together to form one low resistance conductor, and tied the ground from the junction box at the house to the ground at the meter box by the pole.
I expected a modest improvement in the situation, but the improvement was dramatic. During aggressive playback levels, there was hardly any dimming of the lights now. This makes a lot more headroom available for the amplifiers to deliver their full power capability.
RELAYS DON'T LIKE VIBRATION
As part of the testing this evening, and briefly hitting some levels well in excess of what my SPL meter can measure, I discovered that the equalizer in my external processor loop cuts out for a few milliseconds when very low bass frequencies shake the rack. It appears that the output delay relay is chattering from the vibration, causing brief gaps in the sound output of the system when the EQ is engaged. So what does this mean? I've already eliminated the use of turntables, CD players and other mechanically-sensitive audio sources. Now it seems that I have to eliminate anything that has a mechanical relay, lest it will malfunction when shaken.
Come to think of it, I don't like that much vibration either. I briefly turned up the volume on a pounding funk/disco track by Eumir Deodato, and my chest hurt and the pounding was literally knocking the wind out of me. The good news is that the system showed no signs of stress. The bad news is that most of my reel tape collection fell off the shelves and landed on the floor, as did all of my magazines and some software packages from another shelf. And dust everywhere. It seems I need to lay out drop cloths on computers and MIDI keyboards before doing this. The sheer quantity of dust that fell from the ceilings was, well, how the heck can I clean this up?
Well at least the power line and the circuit breakers held. :-)
AN UPGRADED VIDEO DISPLAY, FINALLY
A number of readers of this site have commented about the stark contrast between the big speakers and the small TV. I have kept in mind the desire to move to a better display at some indeterminate time in the future. I just didn't expect it to be so soon.
About a week ago, my wife "pulled the trigger" on getting a 37" display for her wall unit in the living room. She'd been putting up with my old 19" NEC monitor from 1986, which I purchased when I started working on a laser hologram entertainment video and needed some way to see the output of my video signals. She'd been talking about getting one of those newfangled LCD flat panel TVs for about a month. I was getting tired of hearing about it in fact.
Well last week I caved in to her constant pressure and we drove to Costco and picked up a 37" display for her. I was thinking that this would be rather a waste, as she doesn't have a BluRay HD DVD player, nor any program material to feed it that would approach HDV quality. But I figured she would gain the benefit of a larger screen, viewed from across the living room being easier on the eyes.
What I didn't expect was how marvelous it made our SD content look! I was up all night for 4 nights in a row, watching many of my own video productions that I shot with 3-chip Sony cameras. I was stunned at how upconverted SD looked on that display.
So I got interested in the 47" model that Costco was selling. Then last Friday, they dropped the price $200--and that was my cue to spring for it. So on Saturday morning, I returned and bought the 47" 1920 x 1080 native resolution 1080P display.
I can unequivocally state that the results were well worth it. The picture quality is amazing, even with just the SD sources that I have available. DVD movies take on a new perspective. We see and notice more than we did before. And because the display doesn't have to overscan, more lines of the original picture are visible, packing the pixels a little closer together and giving a wider angle view of the scene. That's when I realized that the custom lens hood that I crafted for my wide angle lens, which has a slight vignette problem, is now a problem as I can see the corners of the hood adapter within the active picture area of this panel, whereas this was hidden under the bezel of our former CRT display.
The SD footage looks so nice though. No visible scan lines makes it look like film footage rather than video. The upconverting DVD player does a nice job smoothing edges so that there is almost no jagged edges anywhere. On movie DVDs, film grain is clearly visible. On our video productions, the picture is generally very smooth and clean. CG animation movies also look very good. Overall, a quantum leap from what we had.
My next challenge is to get a DVI to HDMI cable that's about 40' long, to connect my video editing workstation with the LCD panel. Then I can watch some 1920 x 1080 footage I have on the hard drive and see what this baby can really do.
SELLING A LEGEND & ANOTHER GREAT ORCHESTRAL RECORDING SESSION
My goodness this has been a busy and interesting month! Yes, we got the big flat panel display down here, and the wife and I just love it. But our three year old daughter, Amanda, is afraid of it, probably because everything is bigger than life and at her tender age, that scares her. But we're enjoying movies with a new level of enjoyment. Every movie we see that we've seen in the past, it's like we're seeing it for the first time, because we're seeing details we never noticed before on the small screen with less resolution. Now we can tell what film stock the movie was shot on--yes, even the film grain can be seen. I saw Miyazaki's Spirited Away the other night and I was blown away by the luscious detail, the gorgeous colors and the richly-opulent background scenes. It was spellbinding.
Well, to pay for the new screen, I had to give up something, and since my system configuration had changed out the Phase Linear D-500 for a pair of Hafler 500s bridged mono, it was sitting in the rack doing nothing for half a year. Then it occurred to me that it's value had probably appreciated over the years, and with my engineering improvements and superior sound quality, it could be worth considerably more. That hunch turned out to be accurate, as it sold for $3,050 on eBay and yes, the buyer paid for it. I'll miss it, but I had to be rational and consider practicality over the prestige of owning one of Bob Carver's finest. At least it's going to a good home, to live with another serious audiophile.
And now the musical side of things. On Sunday, March 25th, I directed and produced the recording, both sound and video with multiple cameras, of a symphony concert at the Edmond Town Hall Theater in Newtown, Connecticut, a very nice and spacious theater built in 1930 and having excellent acoustics. So well are the acoustics, that one can whisper on stage and it can be clearly heard in the balcony over 120' away.
Well we had a concert of music by famous American composer, Leroy Anderson. Leroy is no longer with us, but my relationship lives on sort of vicariously through his son, Kurt, who is now the heir to Leroy's musical archives. They live fairly close by, and in addition, Kurt is also General Manager of WMNR Fine Arts Radio, another point of contact where I consult with them in an engineering capacity. We spent the late 1990s remastering all of the original LA music onto digital format. It was quite a project. But I digress....
Back to the concert. I had the opportunity to experiment with some various miking techniques, so I had my traditional O.R.T.F. array, expanded with rear channel mics for hall acoustic pickup, and a pair of spaced array mics at the pit in front of the stage, closest to the front row seating. With this many different mixes all recording simultaneously, I found that I have great flexibility with playback mixes here in the studio.
The mics on stage near the conductor provided an ambience-free mix of the orchestra which sounded almost as if they were playing on an open football field. The spaced array picked up some hall acoustic. The back channel mics picked up only hall acoustic. With these three combinations, a large number of mixdowns are possible and I was experimenting with some ideas this evening in Sonic Foundry Vegas.
There are two vocal numbers in the performance (from the Broadway musical soundtrack Goldilocks) sung by Kurt's nephew, Lars Vercelli. I found that the Right Front mic picked up his vocal better than any other mic in the house, so for the stereo mix on the DVD, I'm going to blend this mic in a slightly right of center pan position. The Surround Sound mix will get the on stage mics entirely. Yes, we're producing a DVD video.
For this shoot, I brought in my old friend, Bill Ames, who happens to live a stone's throw from the theater, and enjoys Leroy's music, to be the Associate Producer and operate camera number two on stage. I manned a camera way up in the balcony (Leroy used to call them the "rush seats"). A third camera was stationed between the movie screen and a curtain, trained on the conductor for a medium-closeup. Bill was free to move about, covering the orchestra, woodwinds and brass section and profile shots of Kurt. I got the wide view from above. All of this is sitting on my editing workstation now. The footage looks gorgeous, real eye-candy. Between the burgundy and gold curtains on stage, the ornate architecture of the theater, the tuxedos of the orchestra players and the wood tone of their string instruments, it was a lovely look. And we have great footage from every camera.
I've synched the first half of the concert session videos. I've downsampled the original 24-bit/96KHz audiio to new files in 16/48 format for Dolby Digital encoding and those have yet to be copied over to the video editing workstation. Then they have to be synched to reference audio from the camera. Visual synch was pretty easy, watching the conductor's baton and waiting for the end of a downbeat, where I'd slide all the video tracks and switch between them until I'd matched the hand position. Perfect frame-accurate synch.
So I took a break from editing and just loaded up the 24/96 tracks in Vegas and listened. The sound was so beautiful that it brought tears to my eyes. This recording even outclassed my earlier 2005 recording of the Danbury Symphony. The performance was very good and everyone knew the music and could play it at full tempo and keep it tight. The drummer had a new Ludwig kick drum which he had tuned beautifully to sound deep and rich, like a big orchestral bass drum. His playing technique of letting off the beater gently enabled him to get rich, deep bass out of the relatively small drum. So the percussion was perfect on this concert. It was delicious-sounding. That's 25 years of playing Jazz percussion. We had the best of the best performing that afternoon.
I have always liked Anderson's music, but it was a special pleasure to hear it in 24/96 sparkling, crystal clear digital sound with no surface noise and no audible distortion. In fact, it was the first time that I heard an Anderson performance recorded that sounded live. Sitting here in the studio, listening on the big system just continues to blow me away.
I learned an important secret to high fidelity listening: the playback level must be set correctly. Many people tend to play back louder than life and no wonder it sounds harsh--it's approaching the threshold of pain. In search of the perfect playback level, I brought a sound level meter to the concert and noted levels on several numbers during rehearsal. BTW, the balcony seating only lost 6dB off the front stage levels!
The orchestra, during louder crescendos, was peaking at 97dB, flat, or 88dB A-weighted. I found that my normal listening level had things going to 108dB, way too loud. So I set the level according to the meter reading I got at the edge of the stage. And then something magical happened: the sound was sweet and exactly the way I heard it as I stood in front of the stage Sunday afternoon. When the right level is found, the ears are able to more accurately sense the direction and spread of sounds, and the orchestra seemed to magically appear in front of me once again, about 10' back from where the speakers are sitting.
I listened to the O.R.T.F. array and then the spaced array. Both had their unique character, the former being more visceral and articulate, the latter being mellower and more balanced and a bit wider soundfield. The experience was like the one I had a couple of years ago when I sat in on some rehearsals of the Bridgeport Symphony--a very rich array of sounds and textures of many different instruments across a wide arc in front of me. It sounded as good as what I heard in the front row. Every detail seemed projected out to me, as if I were closer to the orchestra, or as if many individual mics had been placed in and among every instrument. The subtle tones and textures of every instrument are just... perfect.
It never ceases to amaze me that this big hunk of a sound system can be so accurate. It looks like it ought to sound gritty and harsh, but the sound is uncolored. The LLT subwoofers add no color to the bass and there's no ringing like you'd get with a vented design of conventional configuration. So the kick drum was just as it sounded live. The string bass was neutral and you could hear the wood of the double-bass--it had character of the instrument, not "boom, boom." But the mids and highs were not playing second fiddle to the bass. They were as natural and uncolored as can be imagined. I had the unique experience of being there, live, which keeps the memory fresh in mind. The whip crack at the end of Sleighride, makes a great test of speaker transient response. Wow did it wake me up! The full dynamic range of the orchestra is preserved faithfully, so those sonic surprises retain their full impact.
There's much editing work to be done to produce the DVD, but in a month or so, I'll have it all hammered out, with multiple audio track selections and camera angles. The shoot went tremendously well. This is shaping up to be the most impressive DVD title I've authored to date.