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Tubes in a Home Theater?

ORNJ

Member
2011-03-15 11:02 pm
CA
Hey guys, I am a little confused.

I was reading about the 6 Million Dollar theater the other day and noticed that he is using all tube amplifiers in his system.

I was under the impression that tube amplifiers are not good to use in a home theater? Not because of the lower amounts of power they tend to put out, but because someone told me when I first started to get into audio that they cannot handle the dynamic swings that occur in movies....

Is this completely wrong?

I have built some bottlehead gear and really enjoy that tube sound but have never thought of using tubes in my main system for the reasons above.

My wife also likes the looks of tube gear as she really enjoys the "steampunky" look about them with the glow of the tubes and such...she even says "now that is a piece I would want to display"
 
I thought movie sound was so compressed that it has very little dynamic range?

In any case, a competent amplifier (whatever technology) will do the job. Note that 'eye candy' valve amplifiers are not necessarily competently designed: some are, some aren't. Remember, everything spent on appearance was not spent on sound.
 
I agree a tube amp can give the same dynamic range as SS.

Maybe some movie's are compressed soundwise, but I find from my Sat. Rec. it's pretty good. I does vary of course. Some of the std. def. movies can have pretty good sound though.

Don't source your audio from the TV and use the component RCA connections if using analog stereo. On my 2008 22" TV I also found the 3 RCA video component connections from the Sat. Rec. gave a much better picture than using the HDMI cable. Maybe newer TV's are better that way?

The Sat. Rec. has 3 audio settings to set the sound for TV, HiFi , and No Compression. There is a Huge Difference on No Compression and blows away any CD. If you have a cable box also check for those settings.
 
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ORNJ

Member
2011-03-15 11:02 pm
CA
I thought movie sound was so compressed that it has very little dynamic range?

In any case, a competent amplifier (whatever technology) will do the job. Note that 'eye candy' valve amplifiers are not necessarily competently designed: some are, some aren't. Remember, everything spent on appearance was not spent on sound.

I was mainly thinking about explosions, but I guess that really doesnt matter much due to the fact that a subwoofer is usually handling those duties.

What she likes about the looks is only the glowing of the tubes....so the majority of tube amps will fit that bill.

After I posted this I came across the decware zen ultra.

Those look very interesting. The only downside I can think of with something like that is the lack of EQ. However, you can always run a bluray player into a receiver for EQ and then run the pre-outs to the Zen Ultra.
 
While technically not off-topic......Why not all-tube for your viewing & listening pleasure? A vintage McIntosh for the sound & a Top-of-the-line CRT TUBE for your eyes. I really cannot stand Plasmas, LEDs, projectors, at. al.
Our set is a 32' Sony (4:3) 12 yrs old or so. There is a power up surge that has to be heard to be believed! "Once upon a time" Sony made a CRT at about 36" in a 16:9 ratio for a few short years quite the giant thing .....I will be searching for this vintage set when our current one goes POW!

__________________________________________________________Rick.....
 

jjman

Member
2009-01-17 2:41 pm
Well if you think about it, tube amps were the only amps in theaters for a long time. I think the movie "Midway" pretty much qualifies as an explosion rich movie and the theater I saw it in at as a kid used tube amps. The sound was awesome.


"Midway" was the 2nd movie in "Sensurround ". "Earthquake" and "Roller Coaster" being the other 2 that I saw in the theater when they came out in the mid 1970s. I noticed there were colossal speaker cabs in the front. I doubt tube amps were used to create the Sensurround effect which was a low frequency rumble that you literally could feel. Very cool and weird.
 
I saw Midway in the theater with the Sensurround, they located the modules in the rear corners, taking out a series of seats. Cerwin Vega badges were on the 14? ft cube shaped modules.
Great news!! The sub-harmonic track was kept on the current media used when this movie shows up on cable. Most people don't notice it or don't have the appropriate system to hear/feel this effect.


____________________________________________________Rick........
 
While technically not off-topic......Why not all-tube for your viewing & listening pleasure? A vintage McIntosh for the sound & a Top-of-the-line CRT TUBE for your eyes. I really cannot stand Plasmas, LEDs, projectors, at. al.
Our set is a 32' Sony (4:3) 12 yrs old or so. There is a power up surge that has to be heard to be believed! "Once upon a time" Sony made a CRT at about 36" in a 16:9 ratio for a few short years quite the giant thing .....I will be searching for this vintage set when our current one goes POW!

__________________________________________________________Rick.....

Thats not a power surge, just the degaussing coil around the tube doing its job:cool:
 
Well 3CCD HD projectors are much better in most aspects, like gear weight, space it occupies and image size it delivers especially. However most recent movies are lacking natural footage and hi quality soundtracks.

Wish cinematography will change the route at some point from artificial blasts and faked renders to something on a par with Barry Lindon.
 

multi

R.I.P.
2011-01-28 2:52 am
Imagine how good a TV using a CRT with the latest circuits would be.
As far as I can see even the latest TV can't render the fine detail like a CRT. But Modern TV's are huge and cheap to make.
Only thing I see is the cost of running the output tubes when 6550's are getting so expensive and have such short lives. 807's would be good they are cheap and last.
Phil
 

regal

Member
2004-01-04 8:41 pm
MD
movies have a much greater dynamic range than most popular music, by a huge margin. I think it is a big reason for most $'s going to hometheater "industry" over stereo, because the movie mastering engineers remember how to use dynamic rangeno loudness war= better audio entertainment.
 
The reason why big money has been moving in to home theater is because larger screens have gone down in cost along with the multichannel processing and amplification gear. A popular feature on receivers (and now sound-bars) is the dynamic range compression processing. Having dynamic range in the audio track is more of a hindrance than a draw when mass market consumption is concerned.
 

regal

Member
2004-01-04 8:41 pm
MD
Possibly but I think the compression feature is the right way to do things. Imagine if we lived in an audio world were dynamic range processing was left to the end user. People use it when the TV is on watching something mundane or at low volumes. The excitement, thrill of home theater is the raw dynamic range of the soundtracks.
 
movies have a much greater dynamic range than most popular music, by a huge margin. I think it is a big reason for most $'s going to hometheater "industry" over stereo, because the movie mastering engineers remember how to use dynamic rangeno loudness war= better audio entertainment.

Interesting measures in dB

-80 UNDERWATER NUCLEAR SUBMARINE MICROPHONES LISTENING TO SHRIMP CHEWING ON FOOD AT 100 METERS DISTANCE
13 ORDINARY LIGHT BULB HUM

85 BEGINNING OF HEARING DAMAGE, EARPLUGS SHOULD BE WORN

93.98 = 1 PASCAL PRESSURE (SI)

125 DRUM SET-ONLY AT THE MOMENT OF STRIKING
128 HUMAN HEAD HAIR BEGINS TO DETECT VIBRATION
133 GUNSHOT
145 HUMAN VISION BEGINS TO VIBRATE MAKING IT SLIGHTLY BLURRY
165 JET AIRPLANE, BOEING 727-15,000 LBS OF THRUST
180 1 POUND T.N.T. AT 15 FEET
207 BOMB, SMALL SIZED 250 POUNDS
209 BOMB, MEDIUM 500 POUNDS
215 BATTLESHIP NEW JERSEY FIRING ALL 9 SIXTEEN INCH GUNS
310 KRAKATOA VOLCANO ERUPTION-1883 A.D.

I hope movie industry would not tend to reproduce natural sound levels especially KRAKATOA eruption or New Jersey firing. Honestly it would be much comfortable if blasts shots jet exhausts sonic booms and similar noise would be decreased further in volume in compare to speech levels since they are not of realistic loudness in movies anyway.
 

regal

Member
2004-01-04 8:41 pm
MD
85 BEGINNING OF HEARING DAMAGE, EARPLUGS SHOULD BE WORN

.



That's hours, not milliseconds. The beauty of a highly dynamic range recording is the peaks (110+db) are milliseconds while the average can be under 80dB. Real sounds are dynamic, its why the music industry has failed for 20 years while home theater has thrived. Not Mp3, or pirating, or other excuse, poor mastering. Luckily movie industry has in general been smarter. Even a lot of concert videos are better than their CD counterparts.