Next up: What is room pressurization?

[fas42]

There's a possibility that this is just low frequency feedback, talking about vinyl, from speaker back to catridge and arm: the sound you hear if the cartridge is sitting on a non revolving record and you excite a little resonance in the room by banging something.

As a very good example of "real" instrument pressurisation, one version thereof, is to bring a Marshall guitar amp in the lounge, and just listen to the sounds before a real note is struck: the guitarist picking up the instrument, idly touching a few strings on the neck, fiddling with the connectors and switches, the amp burbling, crackling, popping, farting quietly: you just know this is going to sound good, before anything musical happens, that's the type of pressurisation a lot of people are thinking of ...

Frank

 

[JackD201]

How about this. When you feel the music you're getting a nice ol' dose of SPL usually in he bass but midrange frequencies can also be felt on say, the hair on your arms. Perhaps that isn't quite room pressurization. Room pressurization would be a level of excitation of the air molecules in the room. What would make up the excitation? If it were an impulse test it would be the source signal's entire envelope plus reflected energy while the original is still being played back. Excitation can still be present after playback is over and that would be the result of reverberation as well.

I do not have tape but I did grow up listening to it and have played with everything from 2" to compact cassette. So Jeet Kun Mark and Tim Kwon Do, our death blow dealing verbal martial artists can't disqualify my Kung Fu so easily What I hear from Tape is information density in the sustains of envelopes not just in the bass but more so in the mids and lower mids, since we're dealing with sustains here it follows that what I mean is a huge amounts of harmonic content that would no doubt benefit timbre. Some call it bloom but bloom to me deals with decays too so maybe not bloom. I really like it when folks describe it as density. Density implies "pressure" a thickness, fatness, solid-ness, like you could chew on it.

I've definitely heard the bass punch and slam from digital and from 45 rpm LP but I have not experienced this kind of midrange density on digital yet, I've had glimpses of it on Direct to Disc LPs like those from Stockfisch. Yet, not quite or near the same degree. The question is, why? What does tape have or do? Even 16/44.1 has enough to playback print through and tape hiss as does LP. So what Frank calls my "favourite" doesn't apply in this case.

 

[fas42]

Fair enough, Jack ...

With regards to tape, there's always this to consider: http://www.whatsbestforum.com/showt...wig-s-Sound-Page&p=85506&viewfull=1#post85506

Frank

 

[NorthStar]

Frank and Jack, you both have somethin' in common.
And that is the pick up of a guitar, of a turntable's cartridge,
and of a tape recorder's head (R2R or else).

Low Frequency Feedback, I believe is one part of the recipe for room & body pressurization feel.

P.S. Frank, watch out for those typos.
Jack, looks good from here. :b

 

[garylkoh]

Gary curiosu about one thing the woofers on the Gen 1 are they in dipole or monopole config?

I am with you that in the case of an LP (any medium, really) the SPL has to be zero , ideally... if it is rumble then that would be another huge problem if the level was sufficient to pressurize a room ..

They are in-phase and operate at frequencies that are far within 1/4 wavelength apart front to back. With such long wavelengths, dipole does not make sense.

 

[NorthStar]

Gary, I hope you didn't construe my post the wrong way ...

I don't have a car, truck, boat, or airplane.
And I haven't got a passport either (I never renewed it).

Would love to meet you though, in a powwow. :b

 

[fas42]

And I haven't got a passport either (I never renewed it).

Smart move, Bob. There won't be a chance of you being contaminated by mixing with those odd types across the border ... :b:b

Frank

 

[NorthStar]

No Frank, people like Gary and with his immense generosity they certainly deserve to be 'rencontre'.

So much to learn from him.

Then I want a valid passport for a secure transport. Which opens the doors to new frontiers,
deeper discoveries, and for the better ...


And then I can jump in a plane to visit you too Frankie in the bayous of beautiful Australia.
...Jump with the kangaroos from the backcountry sides. And play the 'guimbarde'.
You know what a 'guimbarde' is Frank?
You know, that small musical instrument you play with your finger and your mouth ...


Here:

 

[garylkoh]

Gary, I hope you didn't construe my post the wrong way ...

I don't have a car, truck, boat, or airplane.
And I haven't got a passport either (I never renewed it).

Would love to meet you though, in a powwow. :b

Oh, no. I didn't. No worries. I'd love to meet you too.

I have a customer with his winter home in Gabriola Island. Next time I go and visit him, I'll swing by and come visit with you. He's got a pair of G1's there - and the Clearaudio Statement turntable. It's always a blast to visit because he's got about 10,000 LPs. Last time I visited, he opened a sealed copy of the Mofi UHQR of Crime of the Century. You know how much that's worth???

 

[fas42]

And then I can jump in a plane to visit you too Frankie in the bayous of beautiful Australia.
...Jump with the kangaroos from the backcountry sides. And play the 'guimbarde'.
You know what a 'guimbarde' is Frank?
You know, that small musical instrument you play with your finger and your mouth ...

All in jest, Bob, all in jest ...

Yes, that mouth harp, I regularly play a collection of Canned Heat where there's a long winded, "experimental" track where it features prominently, very effective and endearing ...

And, sorry, I should have included this before, if you decide to pop all the way over here you're very welcome! Nothing too flash, but there's music to share ...

Frank

 

[NorthStar]

Oh, no. I didn't. No worries. I'd love to meet you too.

I have a customer with his winter home in Gabriola Island. Next time I go and visit him, I'll swing by and come visit with you. He's got a pair of G1's there - and the Clearaudio Statement turntable. It's always a blast to visit because he's got about 10,000 LPs. Last time I visited, he opened a sealed copy of the Mofi UHQR of Crime of the Century. You know how much that's worth???

Now we're talkin'! Gabriola Island, no problemo I can meet you guys over there.

Just let me know when you go, and we'll make easy arrangements.
PM me and I'll shoot you my phone #.

I'll bring few nice bottles of red, and we'll have happy times listening to whatever life brings this side of that Island. :b

__________

No, how much Gary? ...Not that I truly care, but now that you 'pressurized' my curiosity, shoot! :b

 

[Soundproof]

I think I know what you mean.

IMHO it is not vinyl wow and flutter - sometimes you "feel" the faders going down and up between the tracks after the music stops - and when they are down the pressurization goes off.

Then it's room ambience that people characterize as pressurization. Here in Europe we have a cable-tv channel called Mezzo, which sends music non-stop. In the evenings they send entire works, but during the day they send short excerpts from their many videotaped concerts through the years. You get all kinds of classical music styles, and all kinds of venues, in short 3-4 minute pieces.
I've always enjoyed listening to the change in room tone between these, something that I become even more aware of because I'm seeing the venues, and seeing how the room tone changes according to place. As these pieces can be the second part of a piano sonata, there is no applause following its conclusion, but they hold for several seconds, before abruptly cutting to the next setting/piece, some seconds before that starts.
In my listening room, it is as if the quality of the air changes with those shifts of venues. A completely different "energizing" of the room takes place, before a tone of music has been played. And again, because you have a visual cue as to the change of venue, you understand why the room tone transmitted has changed, and make the link.

 

[NorthStar]

All in jest, Bob, all in jest ...

Yes, that mouth harp, I regularly play a collection of Canned Heat where there's a long winded, "experimental" track where it features prominently, very effective and endearing ...

And, sorry, I should have included this before, if you decide to pop all the way over here you're very welcome! Nothing too flash, but there's music to share ...

Frank

If I do Frank, we go play with the kangaroos.

Then I'll beat you up real good, after a good bottle! :b
{And don't worry, if you don't know what 'pressurization' is, you will!}

 

[Phelonious Ponk]

Then it's room ambience that people characterize as pressurization. Here in Europe we have a cable-tv channel called Mezzo, which sends music non-stop. In the evenings they send entire works, but during the day they send short excerpts from their many videotaped concerts through the years. You get all kinds of classical music styles, and all kinds of venues, in short 3-4 minute pieces.
I've always enjoyed listening to the change in room tone between these, something that I become even more aware of because I'm seeing the venues, and seeing how the room tone changes according to place. As these pieces can be the third part of a piano sonata, there is no applause following its conclusion, but they hold for several seconds, before abruptly cutting to the next setting/piece, some seconds before that starts.
In my listening room, it is as if the quality of the air changes with those shifts of venues. A completely different "energizing" of the room takes place, before a tone of music has been played. And again, because you have a visual cue as to the change of venue, you understand why the room tone transmitted has changed, and make the link.

This would be a great explanation if we were talking about the recording, but a bunch of folks here are not. They are talking about something that only exists in specific media. They are talking about feeling/hearing this "pressurization" before tracks begin, between tracks, even before the needle hits the record or the tape reaches the recording. They are hearing (we're not talking about deep bass or high spls here so I will now drop the "feeling") something that is inherent in the media when there is no recording present.

I'm afraid it's not "room ambience that people characterize as pressurization," because in most of these cases, there is no room ambience present on the media when the phenomenon is heard. It is noise, heard as room ambience, characterized as pressurization. It's heard before the needle touches the vinyl? It's heard before and between tracks? This is all it can be. There is no other rational explanation.

Tim

 

[microstrip]

(...) Last time I visited, he opened a sealed copy of the Mofi UHQR of Crime of the Century. You know how much that's worth???

Now that it is open as much as mine that has been played tens of times ...

I can not imagine the price of a sealed LP, but what I consider really ridiculous is the high asked price of Mofi sealed digital (CDs) of gold Mofi - 500 usd in ebay Germany for the Crime of the Century.

Crime of the Century was one of my triggers against poor CD sound. For particular reasons, "Hide in Your Shell" had a special meaning for me - it was released in 74, these were epic youth years. But much later the sound of the regular CD was so poor that I was really shocked - now I know that it was in part due to poor mastering. But I still have not been able to listen to a decent digital version of it - but I never listened to the Mofi CD.

Bruce, any opinion on this particular recording?

 

[microstrip]

Then it's room ambience that people characterize as pressurization. Here in Europe we have a cable-tv channel called Mezzo, which sends music non-stop. In the evenings they send entire works, but during the day they send short excerpts from their many videotaped concerts through the years. You get all kinds of classical music styles, and all kinds of venues, in short 3-4 minute pieces. (...)

Sometimes I also enjoy Mezzo in the evening. I have an AV surround system in that room, and unhappily sometimes they have an non natural sound track - too much information in the back channels, sometimes changing your position during the performance and some strange phase effects to increase ambiance. In live recordings sometimes it seems they even increase audience noise during pauses. If you have a surround system I think you are just noticing these changes between recording techniques and ambiance.

 

[rockitman]

Now we're talkin'! Gabriola Island, no problemo I can meet you guys over there.

Just let me know when you go, and we'll make easy arrangements.
PM me and I'll shoot you my phone #.

I'll bring few nice bottles of red, and we'll have happy times listening to whatever life brings this side of that Island. :b

__________

No, how much Gary? ...Not that I truly care, but now that you 'pressurized' my curiosity, shoot! :b

as someone who one a sealed version of MoFi UHQR Crime of the Century at an ebay auction 1 year ago, $350.00 was my winning bid. That's a good price now for a sealed version. Incredible sounding rock record.

 

[Soundproof]

Sometimes I also enjoy Mezzo in the evening. I have an AV surround system in that room, and unhappily sometimes they have an non natural sound track - too much information in the back channels, sometimes changing your position during the performance and some strange phase effects to increase ambiance. In live recordings sometimes it seems they even increase audience noise during pauses. If you have a surround system I think you are just noticing these changes between recording techniques and ambiance.

That's also because the French use a different stereo recording principle, that has actually won out in comparisons for best tv-stereo sound. At times, as a processor tackles this signal when you switch to a French channel, such as TV5 or Mezzo, you get a strange q-sound like phase shifting of the sound, where it can seem as if particularly dialogue begins behind you, moves through your head, before snapping into place over by the front speakers.

@Phelonius
Yes - but what if the media induced noise - tape noise and groove noise - deliver a semblance of room tone, accounting for the stated "pressurization"?

 

[Phelonious Ponk]

@Phelonius
Yes - but what if the media induced noise - tape noise and groove noise - deliver a semblance of room tone, accounting for the stated "pressurization"?

In those cases in which people hear this "pressurization" before/between tracks, when there is no music playing, no recording in the equation at all, I don't see how there can be any other explanation: The media, or the system, is generating a noise similar to room tone that is being perceived/described as "pressurization." Or to take it back a few pages, what Jack said. In those cases in which it is heard at moderate volume, and/or when no deep bass information is present it is, at least, something else being perceived/described as "pressurization." And probably what Jack said.

Tim

 

[JackD201]

Who wants to do the math for quantization of magnetic particles on standard 1/4" tape running at 7.5 and 15ips?

I'm betting it's higher than any commercial digital. Film is supposed to be around 4k, BD is 1080p. The jury is out on if the 4k digital camera backs are as good. Where's Mr. Bob?

In other words, I was hinting at higher probable resolution in tape. Tape hiss and and groove echo I think is not such a big deal as far as pressurization goes. Neither is phase. You get pressurization from both correlated and uncorrelated pink noise. You'd have to be awfully careless at setting up speakers to get a high degree of cancellation. A more believable ambient field however........