Cathedral vs flat ceiling

[Ethan Winer]

Originally Posted by Weasel9992

there is no way to extrapolate from the data how the room "sounds"

Possibly, but if the right things are tested, and the data shows little or no difference, that proves the sound in the room didn't change either. And if there is a substantial difference in what's measured, then that proves something too.

If you want this to be a worthwhile test, you'll have to agree to some kind of subjective element and accept the results as authoritative.

But who's "subjective element" do we trust and go by? And how do you avoid expectation bias? If subjective impression is to be given any weight, wouldn't you insist on being there in person? I sure would!

--Ethan

[Ethan Winer]

Originally Posted by rimskidog

whereby the same pre-recorded material was fed into the room and re-recorded (this time with the room sound added) both before and after.

A room sweep with software is much better than music because that tests all frequencies, not just those frequencies present in the music depending on the key of the piece(s) played.

--Ethan

[djgizmo]

Originally Posted by Glenn Kuras

Ok so it seems as we all agree (well one guy is out but hey that's how it goes) that wood does produce a different sound in a room vs concrete. Now the big question is WHY!!!!

I think Bryan gave the best answer but I would like to hear others also.

Glenn

I've sat and read through the entire thread. (long read at 4am)

I'm in no way smart compared to you guys, but I'm surprised no one but DanDan brought up of other factors that change the way sound is shaped besides DB reflectivity. I don't intend my reply to be offensive, so please try not to take it as such, I'm just trying to participate in a topic with an outside perspective.


The OP asked " Is there a big difference between a concrete floor and a hardwood floor assuming I've done some treatment on the walls/ceiling?"

Ethan answered "There's no difference in sound between concrete and wood, or at least not enough to worry about. Both reflect sound."

I'd have to state just because both reflect sound, doesn't mean they both reflect sound in the same way. Similarly as an acoustic piano playing an A440 note doesn't sound the same as an electric piano playing an A440 note. Even if those two instruments play the same exact note, in the same environment, at the same velocity/volume, one doesn't sound like the other.

Yes, we all can agree that both concrete and wood are reflective. There seems to be a general consensus that a wooden floor sounds somewhat different than a concrete slab floor.


However, can we actually test HOW it is being reflected? What I mean, wood (like Dan mentioned) has grain, flex, and other little variables to it, even if a little. This in reality affects the shape and TONE of wave form being absorbed and reflected back out. I'd bet it actually even effects the direction of the reflection as well.

I suspect concrete has less variables to it in regards to grain and flex, and probably doesn't change the direction of the reflection as well.

With all this said, if the wave form shape and tone of a wood reflected sound is changed, then those harmonics of that wave form would also be affected as well causing the reflection of the sound to sound different than the source itself. I'm just shooting from the hip here, but if any of what I mentioned is true (even if its just within the ballpark) that would cause the reflection itself to be a form of harmonic (just the tiniest chorus effect), to the originating sound source.

The only way I can think this could be test accurately would having multiple mics in a room (say 10-15 placed throughout the room, with 1 right next to the source), record several different sounds in a room with a concrete only floor. Then same exact test in wooden floor environment.

Run both of those through recordings through an Multichannel RTA (one that supports digital time analysis)to analyze how the reflections are reflected back to not only the source, but different parts of the room. This would help determine not only the change of shape/tone of the reflection, but via the support of digital time analysis, it might also provide direction of the reflection as well)

Lastly, somewhere in the thread it was generally stated that scientific fact outweighs opinion at every turn. I'd normally say this is true, but I've never heard a scientific fact sell records. It's opinion that sell records and the manipulation of that opinion that sells records.

[johndykstra]

Originally Posted by dykstraster@gmai

There's differences in the resonant properties from one species of wood to the next. Made evident in guitar building. A solid body telecater made from swamp ash sounds different than the same guitar made from say poplar or mahogany. Given these diffences within the family of wood, how can it be that concrete will behave nearly the same as wood, since not even all wood is the same?

hmmm...

[Ethan Winer]

Originally Posted by djgizmo

can we actually test HOW it is being reflected?

Yes we can, and I already described such a test. You place a loudspeaker a few feet above the floor, pointing down, and measure the response of the reflected sound that comes back. This is very easy to do, and gives exactly the information desired - what frequencies are reflected and by how much.

I've never heard a scientific fact sell records.

By that logic we should never care about any specs for any gear, yes? So you're happy to buy a power amp without knowing how much power it puts out, or how far down the response is at 20 KHz, or how much THD and IM distortion it has? That's an interesting concept, and maybe I'll bring it up to the International Standards Committee.

--Ethan

[djgizmo]

but how does a frequency response show the direction and shape of the reflection. I'm just curious as I'm venturing in new territory

As for the gear specs i agree we should care about specs. But saying opinion doesn't matter about gear is a subject as long as analogue vs solid state.

[Ethan Winer]

Originally Posted by djgizmo

but how does a frequency response show the direction and shape of the reflection.

When you measure as I described, you can determine the strength of the reflections by the extent of the peaks and nulls at various frequencies. If a surface reflects 100 percent, then the peaks will be 6 dB and the nulls will be infinitely deep. It's easy to calculate reflectivity from other null depths.

As for the gear specs i agree we should care about specs. But saying opinion doesn't matter about gear is a subject as long as analogue vs solid state.

I think you're confusing subjective opinion, which of course matters, with scientific fact which also matters. If different surfaces reflect differently, then one person's "better" is no more or less valid than another's. But if the surfaces reflect the same, or within 1/4 dB of each other, then there's no need for subjective opinion because there is no difference whether some people believe there should be or not. Which is kinda the whole point of this thread.

--Ethan

[quincyg]

So what does any of this have to do with Cathedral vs flat ceiling??? Maybe this thread should be reorganized into a thread titled concrete vs wood for studio flooring.

[heyman]

To the guy building the studio.. The original poster..
Concrete vs Wood.

Do this..

Grab a stool and mic up an acoustic guitar in a room with a concrete floor. With one mic about 6 - 12 inches away from the sound hole..

Record that take.

Now Place a peice of plywood (4x8)? on the floor under the stool and under the mic.

Record that take.

Play them both back and compare.

You will be able to hear a diffrence and thats with one piece of plywood!


I wont say which one is better, but there is a reason why Wood floors are in most major studios.

[DanDan]

This thread is doing my head in. I can't figure out how to stop the emails, i.e. unsubscribe to it and it just keeps on and on and on and on, like a broken record. There is no possible resolution to the basic differences of opinion. I firmly believe continuation of the thread is a very bad thing for the forum and for the reputation of those posting. It is a cancer.
Jay, I would like to formally request that this entire thread be at least stopped, preferably deleted. I am asking anyone who agrees with me to post, now. Perhaps if we get a bunch of votes, Jay will find a way to bend the rules.

Enough, DD

[johndykstra]

I vote for a lock

[Ethan Winer]

Originally Posted by heyman

Record that take.
Now Place a peice of plywood (4x8)? on the floor under the stool and under the mic.
Record that take.
Play them both back and compare.

That is highly unscientific because the sound difference between performances will far outweigh the difference between plywood and cement. However, if you record a guitar and played that through a loudspeaker over different floor surfaces, then you'd have a valid comparison.

--Ethan

PS: Dan, I feel your pain.

[DanDan]

Pain indeed. Ethan as a primary and frequent poster in this debacle, your vote would have great significance here. Could I prevail on you to cast it?
Everyone else, c,mon, please do vote, life will be better without this thread.
DD

[andrebrito]

I will only say this once !



From Acoustics of Wood book - pg. 22 - Voichita Bucur - Springer Editions

Wood vs. cement is now explained

[Trev@Circle]

Interesting. What does it mean?

Originally Posted by andrebrito

I will only say this once !



From Acoustics of Wood book - pg. 22 - Voichita Bucur - Springer Editions

Wood vs. cement is now explained

[Glenn Kuras]

I am with Dan on locking, BUUUUUUUUUUUUUUUT andrebrito can you give a little more detail on this?

Glenn

[Glenn Kuras]

Originally Posted by Ethan Winer

That is highly unscientific because the sound difference between performances will far outweigh the difference between plywood and cement. However, if you record a guitar and played that through a loudspeaker over different floor surfaces, then you'd have a valid comparison.

--Ethan

PS: Dan, I feel your pain.

Interesting. Unscientific, yes but a valid way to see which sounds better. If not you have some deleting to do on your own web site. lol lol

Glenn

[DanDan]

3 Votes to lock. C'mon Ethan, do the right thing. I think only your vote will put this sad obsessed arthritic donkey out of it's misery. If you don't it will turn uncomfortable again. It has repeated every other trait, so ugly is coming down the track.
It is obsessive to continue.

DD

[Trev@Circle]

I hear what you are saying dandan but, given that I'm about to lay down several grand on a wooden floor it would be very useful to understand exactly what andrebrito is saying. While I absolutely agree that the pointless bickering should stop and we don't need to hear the main protaganists on the subject state their case over again if andrebrito"s point may actually shed some light on this then it would be a misguided point to bring the discussion to an end until we've heard it. No?

Originally Posted by DanDan

3 Votes to lock. C'mon Ethan, do the right thing. I think only your vote will put this sad obsessed arthritic donkey out of it's misery. If you don't it will turn uncomfortable again. It has repeated every other trait, so ugly is coming down the track.
It is obsessive to continue.

DD

[DanDan]

Trev, Andrebrito's point has been made before, without the graphs.
He is pointing out that different angles of incidence genarate entirely different responses, in the case of Maple. However, this Maple is not specified, it appears to be unfinished wood with a relatively rough surface. An epoxy coated Maple would be have a lot less variation, and be quite similar to any other hard material coated with epoxy or such hard coats. It may be worth your while considering stained, polished concrete. Google it and see what you think. I doubt if it is cheap, and I woudn't fancy the colour or the texture. However it is perfectly viable. If you like it, it can certainly be worked into the design. I was in a fine Studio in Liverpool, with Steel being the main ingredient!
If you want to tease this out further, please feel free to mail me at soundsound@eircom.net or phone me at
+353-21-4896250
+353-87-9034498

The price of this consultation will be your vote to close this thread ;-)

Best Regards, DD

[Ethan Winer]

Originally Posted by DanDan

this Maple is not specified, it appears to be unfinished wood with a relatively rough surface. An epoxy coated Maple would be have a lot less variation, and be quite similar to any other hard material coated with epoxy or such hard coats.

The last time Andre posted that graph I asked a bunch of questions which he never answered. Like how thick the wood is, how it's suspended, etc. I doubt that data is for wood on top of a solid foundation, which is the context of this discussion. Andre?

--Ethan

[Ethan Winer]

Originally Posted by DanDan

If you don't it will turn uncomfortable again.

I'm with Trev. This discussion has a ton of useful information and should not be deleted. The only time things become uncomfortable is when people don't behave like adults. The main problem with this thread is the wrong title. I'm not opposed to starting a new thread with an appropriate title, but what would that really accomplish?

--Ethan

[DanDan]

I can see there is a slight softening of views and gradual acceptance of reality. However, I don't think disputed information is particulary useful. I think the thread has shown incredible creativity applied to what was really , bickering. I find that a bit sad. How about voting for a Lock then Ethan. If it did nothing else it would 'prove' that agreement is possible here ;-)
Regards, DD

[Ethan Winer]

I don't understand the problem Dan. I really don't. Compared to some flame-fests this one is pretty tame.

Also, it's not up to me to lock or delete threads. I imagine the GS gods have seen your petition!

--Ethan

[DanDan]

Jeez, what an idiot I am, I have just spotted the unsubscribe below.

Bye Bye, DD

[sweetmojo]

I'd like to see andrebrito explain the graph in his post as well.

[quincyg]

Originally Posted by Ethan Winer

he main problem with this thread is the wrong title. I'm not opposed to starting a new thread with an appropriate title, but what would that really accomplish?

--Ethan

It would make it easy for people to find when researching concrete vs. wood.

I am building a cathedral ceiling room right now and not really finding much information of use after wading through pages of concrete vs. wood.

I am also planning to do a finished concrete floor to save some money, which makes this thread useful after all...but mis-labeled

[FirstLoveStudio]

Originally Posted by Ethan Winer

I don't understand the problem Dan. I really don't. Compared to some flame-fests this one is pretty tame.

Also, it's not up to me to lock or delete threads. I imagine the GS gods have seen your petition!

--Ethan

Sure the fact that wood resonates more than concrete makes a measurable difference? If you're recording a band playing on a wooden floor, you can feel a whole lot of energy under your feet, on a concrete floor there is very little. Same is true if you lean up against a wooden wall compared to a concrete one. the fact that the surfaces in the room vibrate in sympathy with the vibrating air, must have a measurable impact?

I do however agree that audible differences should be measurable, but I also know that I've never heard a recorded sound that completely represents what my ears can hear - I wouldn't say mics + preamps are that good yet

[andrebrito]

I did answer your questions, this was tested in an impedance tube, no other information is given on the book.

Maybe there's a publication on this matter but I don't have it, search on AES JASA etc

Still it shows that wood sounds different than cement because that variance is due to the internal wood structure

[Ethan Winer]

Originally Posted by quincyg

I am building a cathedral ceiling room right now and not really finding much information of use after wading through pages of concrete vs. wood.

Agreed - the discussion veered away from cathedral ceilings around the third post.