Bass Pig's Lair Gets a Projection System

[basspig]

Today I added the fiberglass panels, 2 layers deep, to each of the wing walls that flank the left & right of the screen. They function as bass traps.

I ran near field sweeps on the center and midrange speakers, which turned out to be much flatter than I expected with the EQ bypassed. I did some final and minor EQ tweaking to smooth out out to perfection and sat and listened--for the next 3 hours--to various CDs.

The difference was as if someone had swapped out an industrial PA system for some Wilson-Benesch Bishops. Literally. The phase coherency is the best I've ever heard. Remarkable was the ability of the system to, with certain electronic recordings, make sounds appear as if they originated from INSIDE my skull. I noticed a clear, palpable sense of sounds at various distances in the Z axis. I heard sounds far to the left of stage and all the way through center stage, on these stereo recordings, even though the center channel was completely dormant due to lack of surround program material. Essentially, I was hearing better center channel presence with the two stereo channels than with a center channel in typical Dolby surround. This, of course, with the Carver Sonic Hologram Generator engaged. With it engaged, I am immersed in a literal sea of sounds, but unlike a month ago, the sounds of individual instruments are so solidly and separately fixed in space, that it was like I had swapped in some magical speakers.

This is all due to acoustic treatment at the front stage area. The front of the room is so dead that there are no early reflections to smear the inter-aural time arrivals of sounds eminating from L,C,R speakers.

Interestingly, when I ran the sweep tones, I didn't hear the usual comb filtering (fluctuation in loudness of the tone as it swept through 20-20,000Hz) that I always heard in all my years of prior testing and measuring.
The bass response has smoothed out considerably, too. But due to the grouping of drivers, I've eliminated the phase cancellation (power alley effect) and I'm producing the same levels of deep bass with 6dB LESS power. Without trying, I pinned the needle on the 140dB scale on my sound level meter this evening, during a very brief test (my inlaws are living upstairs, so keeping it sane as possible here). And just 0.5 seconds of pulsed loud (a twist of the wrist on the volume knob) sound dropped more dust from the ceiling than an hour of constant loud listening did when the woofers had a big gap down the middle. Wow... what I was missing all these years!

I listened to a variety of recordings, both made by my company and my competition and found new nuggets of sonic nirvana in places that went unnoticed before. The ringing of the room was blurring things substantially before, and subtracting that and the comb filtering from the equation leaves a listening experience like that of high quality headphones, with the added benefit of tactile sensation.

And the interesting aspect of it all, is not a single speaker to be seen.

 

[basspig]

Not much to report today, as I ran out of hooks for curtain hanging.
However, I did have some guests over today. Ethan and his wife spent about an hour, as we previewed some demo reel and scenes from 2001, the most-requested film in my collection.
Ethan explained to me how I could make a less expensive bass trap for my corners with fiberglass batt insulation, as I mentioned that each carton of 16 rigid tiles was $88. For half that, I could make two bass traps using the batt fiberglass.
My next major project will be building resonant plywood panels for the back wall. I hope to make the back wall "disappear" at very low frequencies, with the intent of reducing backwave interference (standing waves) at 16-20Hz. Since the seating position is in the location nearly halfway toward the back, where, theoretically, the null would occur at 16-20Hz, it is desirable to absorb that range at the back wall.
Also to do is make a variety of diffusors, with the intent of making the back end of the room live and increasing the reverb time.
The theater itself is comfortable, functional and sounds & looks great.
Perhaps I'll do a short video tour next.

 

[Vinculum]

Looking good, my friend!

Waiting for the pictures of the final curtain!

I see you either moved your jack post back near the projector (maybe that one was always there) or removed the one that was always in the front-middle of your speakers. Did you reinforce your structure to compensate or just calculate that it probably didn't need to be there?

I may try and work out a date I can come up and get a demo within the next couple months, and perhaps bring a fellow enthusiast from the AVSForum? Hopefully we can work something out via email. Its only a 4.5hr drive

Dr V

 

[basspig]

Hi Dr. V,

Nice to hear from you again!

We're nearly completed with the work. I'm shifting attention toward noise abatement partitions and acoustic absorbers for the rack and computers to silence fan noise. Probably some movable partitions filled with fiberglass.

I spent two weeks evaluating whether a column was REALLY necessary at that location. I lifted all the ceiling tiles and inspected the carrying beam. It's five hardwood 2x12s sandwiching 3/16" thick steel plates, lag bolted together. It could probably support the Conde Naste building in NYC. In addition to that, there's a reinforcing wall above it that has plywood under the sheetrock, for reinforcing it. It acts like a 8' thick truss. The carrying beam does nothing more than act as a cleat to attach the floor joists. The stiffness comes from the wall. Although the beam itself is certainly strong enough to do this job by itself. I put the columns in as habit because my last house (which needed them) was contractor built and had them, and this was also a wall at one time, which I removed in 1983 to expand this space.

Couple of months would be great. This place is best when it's cold outside and I can open the windows. There's enough BTUs produced by computers and audio/video gear to heat the entire house.

And by all means, bring an interested friend. When I first invited Ethan, he visited with Kal from Stereophile. Now it would be a neat trick if I could get Peter Aczel from The Audio Critic to visit this listening space.

I'll have some more updates soon... got the rest of the curtains made, but need one more 3/8" U channel to hang them on the lower tier.

Was doing sweep tests from 20Hz to 10 Hz last night and discovered the curtain hooks were rattling against the U channel at 10Hz when the level was as low as 96dB. I got a clever idea and put rubber grommet material along the entire track. Problem solved. Discovered an interesting phenomena when the 10Hz (inaudible at that level) was playing--speaking to one another, our voices were garbled! It was like our speech was being amplitude modulated at 10Hz. Very weird sensation.

 

[basspig]

Finally finished hanging curtains today.. got the rest of the 3/8" track painted and installed, with obligatory "Bass Pig tested & approved" rubber grommet anti-rattling gasket.

Here's a head on shot:

Here's another view:

All I can say is "Whoa, baby!"

 

[Vinculum]

Your system is what back in the muscle car days would be called a "sleeper". The unknowing wouldn't expect 10 18" bass drivers behind there! Does the screen move at all at spirited playback levels?

Dr V

 

[basspig]

I'm very familiar with the term.. I had a buddy back in the day who had one of those old land rover vehicles that he had dropped a 350 V8 into and by the looks of it, you didn't expect much.

...and one would much less expect the four Bassmaxx drivers to be doing the work of 16 conventional 18" drivers either.

Since the wall of sound is distributed over such a large area, SPLs can get quite high without visible screen vibration--much higher than any acceptable movie soundtrack playback would be. And when the levels do get high enough to vibrate the screen visibly, one can't tell anyway, because the eyeballs are shaking around in their sockets so bad that EVERYTHING appears out of focus anyway. In other words, if the screen is shaking, that's the LEAST of one's worries.

I have my new M1-DA DVI cable hooked up to the IN82 and am now able to play HD video off the editing workstation with VLC Media Player on the second monitor. It took some configuration to get both displays optimized, but now it's very flexible. I can play daily rushes immediately and watch them on the projector. Rendered 3D animation... right out to the projector. Just what I wanted.

My one remaining challenge will be to figure out how to widen the projection angle without spending a huge sum of money. Either that, or, in a year or two, upgrade to a LED projector (which hopefully by then will be way beyond 700 lumens) with a more capable lens that allows wider angles at shorter distances. If I could get a 1:1 ratio where at 11' I get an 11' wide image in 16:9, and about 2500 lumens with a real contrast ratio of at least 5,000:1, I think that'd be about right.

But for now, considering the amount this whole setup cost me, under $2500, including the new seating, I think it's fine.

 

[basspig]

I'm Googling around for a 75-100mm diameter plano-concave lens to use in front of the projector, to increase the image size. I have a plano-convex lens, 6" in diameter, that I've had for about forty years, but it's bends light the wrong way (makes the image smaller).

Most lenses sold at scientific outlets are 25.4mm, too small for my application. And expensive for the size, too.

Mabye eBay has something...

The search for a bigger picture is on!

 

[basspig]

I took my CINEALTA with Rode NT4 mic to a car show this evening in town. I used Detail Off, CINE1 gamma, Cine matrix and +10 saturation level. Shot 38 minutes in 103 individual clips. Got home, dumped to HDD, threw it all on the Adobe Premiere timeline, trimmed the edges of each clip, dropped in a constant power fade between the audio of each clip, nested that timeline into another and applied unsharp mask, radius 0.4, level 0, amount 100. Rendered out to Apple Quicktime Photo JPEG at 97% quality setting. Fired up the InFocus projector and played it from VLC Media Player to second monitor (the projector on M1-DA DVI input).

The footage looked cleaner than anything I've shot prior, and more amazing because this was shot at dusk (8PM) and we were in the shaded side of some buildings with the sunset sky very bright in the background. Rendering out to Quicktime, I ended up with a 29GB HD video file that plays nicely and doesn't visibly degrade the images. Essentially, it looks better than Blu-ray!

The way CINE1 handles the light is just amazing. There was nothing over or under exposed, despite the absurd contrast. I even shot a sunset, in which all forground detail was clearly and colorfully visible, yet the CINEALTA captured the setting sun, while maintaining the foreground scenery in a believable relative contrast.

The IN82 is 30-bit color, and somewhere along the line, it comes out way ahead of the LCD, because there is no banding anywhere, and the shadow details are breathtaking. The DLP projector produces a far darker black than my LCD, revealing details in the darkest parts of the scene. The freedom from noise becomes more apparent--my LCD was exaggerating any little bit of noise, making it look more contrasty because of the lack of bit depth, whereas the new projector seems to show a more accurate representation of the CINEALTA's recorded images. Everything, from the street lights to the sunset, to the antique automobiles and the motorcycles with the flashing LED lighting, looked stunningly-beautiful. I made a 29-minute video edit and I watched it three times on the projector this evening. I just couldn't get enough of that eye candy!

Then there's the audio aspect of it. A car show is a great event, because there are big bore V8 engines everywhere in sight. An people everywhere, a sea of sounds in all directions. The X-Y configuration makes a great, wide stereo soundfield and the CINEALTA's inputs were silky smooth and free of anything added that was not in the environment. I never use AGC, preferring to use manual levels. I set them for the loudest anticipated sound and leave them alone.

When the show ended, and the cars started up, it was a smorgasbord of deep-throated sounds that rattle yer guts when played back here in the theater. There were some Shelby GT500s and some really customized chopped & dropped dragsters with some low tone mufflers that were just loaded with deep bass sounds. As they rolled by, oh baby!

I went over to a side street where a group of Harley owners were getting ready to take off. So I positioned myself downhill from them and used telephoto to compress the view for a theatrical effect. It was almost twilight now, and their headlamps were on and generally aimed directly into the camera lens. But the rest of the scenery behind them was clearly deliniated as was the faces of the cyclists themselves. Then they took off, heading down the hill past me. A sea of rumbling Harley Davidsons making that big rumbling sound as they passed by. What a sensation!

Overall, the "film" was a joy to watch, and I didn't even have to author a disc to watch it in the theater here. And I had some of the lights on in the room, but had forgotten about it because the projector is so darned bright, given it was intended to fill a 260” screen and mine's only about 154”. The sunset scene was making me squint, in fact.

The footage wasn't perfect.. I really need a steadicam vest, because there is too much side to side wobble and jerk when I walk, but when movement settled down, the view was spectacular. CINE1 all the way! Cine matrix really gave it the color of film, too. Slightly subdued reds, but still very satisfying. And clean at -3dB gain. Absolutely stunning pictures when projected. Sharp, noiseless (to the eye) and with dynamic range approaching the human vision. The camera saw everything I could see, as I saw it, save for the cine matrix subdued reds and the projector displayed it faithfully.

A lot of people would be about to walk into the path of my lens, suddenly notice me, and duck out of the way or hesitate. A middle aged couple actually apologized for walking down the sidewalk that I was filming from. While the CINEALTA is low-key, compared to the 70lb Panavision monsters, I guess a number of people still sense that there's a pro cimematographer at work on the streets there, despite my Hawaiian shirt and flip-flops.

There is no greater pleasure than watching your own production on your own theater!

 

[lsiberian]

Nice setup Pig.

I hope to build a theater someday. I plan to use rockwool or fiber as well. I'll deaden the entire room though.

I bet your heard less up stairs too.

You are a seriously sick man. That setup is just sick. I can't believe it. Now I've drooled all over my desk. Nicely done.

 

[Vinculum]

Mark,

Your description of the car show, quality of the capture and subsequent playback make me slobber and drool as well! I hope you'll have some of these for demo when I visit!

Dr V

 

[basspig]

Yes, I'll be the first to admit to being an abnormal audiophile. I redefine "loud". Even a rock band member, whose motto is "if it's too loud, you're too old" thought it was way too loud at levels below MY normal listening levels for rock music. Another friend of mine argues that my subs are not subs, but industrial shake tables. Others just ran out of the studio as I advanced the volume on a Korean pop tune with some heavy bass. Another friend of mine says he gets chest pains and has trouble breathing when I played him some organ music. To me, it's just ecstacy. Maybe I AM off my rocker...

How much of the room to deaden may be a matter of aesthetics. Personally, I like the LEDE approach, because there is some reverberation from the back end. You definately want to eliminate early reflections from the front though. Bass trapping is very important, especially in a situation where you have bad room dimensions like I do, which cancel nearly all bass at the listenng position. I am working on a design for plywood resonant panels at the rear, hoping to absorb the 16-20Hz range so it doesn't reflect back and cancel those frequencies at the listening position.


I intend to keep the demo reel, barring hard drive failure, for future demos. Especially folks into classic autos and auto racing, for them, this reel is a lot of candy. I'm hoping to collect more exciting footage soon. I already have on Blu-ray, the New England Air Show, complete with Kent Shockley wrecking his jet powered truck for the first and only time in 25 years, the Thunderbirds, various stunt pilots, etc, and I'm going to put the fireworks on Quicktime file shortly so it's all ready to play.

In a pinch, I can play the files right off the camera, so I can shoot a scene, and seconds later, plug the camera into the workstation and open the folder on the SxS card, choose a clip and play it in VLC Media Player in raw format off the camera, right on the projection system. Generally I prefer to process, detail enhance and color correct and then render out an edited sequence though.

 

[lsiberian]

Yes, I'll be the first to admit to being an abnormal audiophile. I redefine "loud". Even a rock band member, whose motto is "if it's too loud, you're too old" thought it was way too loud at levels below MY normal listening levels for rock music. Another friend of mine argues that my subs are not subs, but industrial shake tables. Others just ran out of the studio as I advanced the volume on a Korean pop tune with some heavy bass. Another friend of mine says he gets chest pains and has trouble breathing when I played him some organ music. To me, it's just ecstacy. Maybe I AM off my rocker...

How much of the room to deaden may be a matter of aesthetics. Personally, I like the LEDE approach, because there is some reverberation from the back end. You definately want to eliminate early reflections from the front though. Bass trapping is very important, especially in a situation where you have bad room dimensions like I do, which cancel nearly all bass at the listenng position. I am working on a design for plywood resonant panels at the rear, hoping to absorb the 16-20Hz range so it doesn't reflect back and cancel those frequencies at the listening position.


I intend to keep the demo reel, barring hard drive failure, for future demos. Especially folks into classic autos and auto racing, for them, this reel is a lot of candy. I'm hoping to collect more exciting footage soon. I already have on Blu-ray, the New England Air Show, complete with Kent Shockley wrecking his jet powered truck for the first and only time in 25 years, the Thunderbirds, various stunt pilots, etc, and I'm going to put the fireworks on Quicktime file shortly so it's all ready to play.

In a pinch, I can play the files right off the camera, so I can shoot a scene, and seconds later, plug the camera into the workstation and open the folder on the SxS card, choose a clip and play it in VLC Media Player in raw format off the camera, right on the projection system. Generally I prefer to process, detail enhance and color correct and then render out an edited sequence though.

I can't really stand loud volumes lol. But I love a live sound. My current speakers sound wonderful to me. Though my next setup will employ a lot of what I learned from Chris(Wmax) he's one of our speaker fanatics.

Definitely hook us up in the DIY area of the forum. We can always use more helping hands. My style is budget oriented. I look for deals and cheap tweaks to make them the best they can be. Nothing in my system cost more than 300 bucks. Most components were under 100. Yet it beats anything I've ever owned in laps. Once our living room is setup I'll get some updated picks.

 

[basspig]

The thing here is what's a definition of "loud"? There is no one definition. For the ailing grandmother with hormone troubles, that could be 72dB. For the war veteran who just came off active duty, that could be 140dB. "Loud" is a subjective judgement tied to one's own perceptions, experiences and expectations.

I think it's safe to say that if the program material is being enjoyed, the listener tends to prefer it louder. If the sound is clean and the response is flat and material well recorded, louder can be quite acceptable, if not enjoyable.

Depending on my mood, and whether other people are around, as well as the music, I may like it moderately loud, or I may like it at physically-stressful levels, the kind where after one song, you're knees feel like buckling. It's not such a good after effect, but the sensation during is one I highly seek after.

But hey, it's sound instead of LSD, crack cocaine, or other dangerous mind-altering substance. Nirvana without narcotics.. er.. 'sonic narcotics' if you will..

 

[basspig]

Just added a Zektor MAS7.1 to my setup and wired analog outs from both Oppo and Sony players to it and the HDMI as well. It switches both players and the audio and it all comes out one set of 8 analog channels.

Tomorrow night, I'm going to watch my brand-new Blu-ray disc The Sky Crawlers by famed animator Mamoru Oshii. I'm going to watch it in Japanese by myself, and again in English with my wife, daughter and the inlaws on the weekend. Waiting and hoping for more anime to be released on Blu-ray. Even though I already own a DVD of Final Fantasy: Advent Children, I'm tempted to get the Blu-ray version of that film, too.

Projection has turned every film into a whole new experience--even familiar films become like a new experience again.

'Was watching my Blu-ray master disc of the GBSO that I produced last October and comparing the sound with/without the center speaker. Anita Chen's violin and piano literally LIVE in that center channel! The proprietary miking technique I used has tremendous channel separation between the three front mics and hearing the center mic discreetly really brings the solo parts out in front, up close and personal. This is one of my favorite demonstration discs because it is the best recording I own--in terms of accuracy and faithfulness to the original sound heard from the 4th row.

I could watch and listen to it over and over again. Except that we got a $544 electric bill for Jul-Aug billing period. Ouch! The IN82 uses 375W of power and the sound system probably sucks down a couple of kilowatts at idle.

 

[basspig]

I watched The Sky Crawlers in Japanese this evening and was in for an unexpected sonic delight. Apparently Skywalker Studios did the sound design for this Japanese anime film, and the aerial dogfight sequences were quite unexpectedly stunning.
This was the most enjoyable anime viewing experience I have ever had. Probably a lot is due to the theater environment itself, but the film was well-executed as well.
This was one of the few films where the surround was done in such a way where the soundfield was often seamless, forming one huge wraparound of sonic lusciousness. Story was downright weird, but Mamoru Oshii delivers it in much the style of Stanley Kubrick, slow and immersively.

 

[Vinculum]

Mark,

Did you make some surround speakers? I don't recall seeing what you are using for surrounds.

Dr V

 

[basspig]

Mark,

Did you make some surround speakers? I don't recall seeing what you are using for surrounds.

Dr V

Back in 1998, I rescued some AR-17s from the trash dumpster at WVOX in New Rochelle, NY. A year later, I found some Dynaudio Acoustics 9" woofers and tweeters (with 4" voice coils on the woofers) and modified the cabinets to take this odd-size woofer. They sound more like 12's than 8's and handle a lot of power. I used them for studio monitors for a few years, then in '07 I repurposed them temporarily as rear surrounds. I also have another 'delay' system with 15" drivers and dual piezo tweeters that I built in '76, but they mostly sit dormant now.

 

[basspig]

New Speaker Configuration "Rocks"

The relatives were out at DMV this afternoon while my daughter was in school. I had a chance to do some serious listening today...

Holy smokes! 129 decibels hitting the listener chair when the 'signal present' LEDs start to flicker on the power amps. Sat and listened to a few 'disco' songs at these "low" power levels. It felt like a jackhammer was hitting my chair from all directions! Quite unnerving and a bit uncomfortable sensation. New speaker configuration is just outright INSANE. Elimination of 'power alley' effect plus mutual coupling increased efficiency four-fold.

When I briefly pushed the level up about 12dB, the chairs started to dance on the concrete floor! A few ceiling tiles got sucked out, and lots of dust fell everywhere. The CEL SPL meter hit the peg on the 140dB scale. I thought my ear drums were going to explode. Twelve watts would be more than enough amplifier power for normal music and movie watching. Because that was the peak power output level when the SPL was reading 129dB. That means only 1/10th of a watt is needed to reproduce the 105dB full crescendo of the Bridgeport Symphony Orchestra.

The benefits of "mutual coupling" are greater than I had imagined. I gained more than 6dB increase in sensitivity below 75Hz by grouping all the speakers together. The difference was even audible outside in the yard. I've discovered the audio equivalent of a "unified field theory"

I'm still cleaning up the mess... everything fell of every shelf everywhere. And I never tripped the 20A breakers in the power amp racks, despite being terribly underrated for the potential load.

 

[Vinculum]

1/10th of a watt should keep those electric bills low!

I've awoken early to go hear a friends new subwoofers, a pair of Seaton Sound's Submersives (dual opposed 15" drivers in a sealed box). Next week I'm headed to NJ to go hear some Legacy Audio Whispers. Anxious to hear a good dipole and what all the fuss is about! And in November I'll be on the the AVS cruise to the Caribbean. Sometime before then maybe we can get together and make some chairs move. My audio plate is filling up!

Dr V