ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
moving my studio to a smaller room
#613711 - 09/05/08 09:40 AM
|
|
|
Marriage and lifestyle changes and all that, and I've moved out of this
place (my first SOS post I think), on to a bigger home but a rather unsatisfactorily
small music room only 375cm by 272cm by 242 cm high. Here's a pic.  I haven't run modecalc on those dimensions yet,
but I will. I have 4 mini traps and some Auralex, which I'll suitably place. I
had KRK Rokit 8s in the old place. I'm guessing they are too big for the new room, so I
rashly bought a lightly-used pair of Klein and Hummel O110s on ebay. They haven't shown
up yet. So anyways, is proper bass monitoring possible in small rooms? The
range of stuff I like to work on includes hip-hop and dance music, so I'd like more bass
than I expect out of the K&Hs. If I were to pair a sub (with crossover) with the O110s,
would the bass be just as problematic in the small room as with a pair of 8' woofers, or
worse? I fully expect to be told by you lot to go out and get some proper
headphones, so I'm eyeballing the Sennheisers that have been recommended elsewhere, but if
it's in any way possible to get pumping bass in this shoebox, I'd sure like to. thoughts? ryan
-------------------- http://ryanmead.net
|
Glenn Kuras
Joined: 22/12/05
Posts: 339
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#613789 - 09/05/08 01:21 PM
|
|
|
I will say your room is pretty small, but with enough bass trapping (more then 4) it can
be done. In fact you would not be the first one, MANY have done mixing in rooms that size
with much success.  Glenn
-------------------- www.GIKAcoustics.com
Now with offices in the USA and Europe
|
magicdog
member
Joined: 25/04/01
Posts: 379
Loc: Oxford
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#613912 - 09/05/08 07:48 PM
|
|
|
I think you would be better off to avoid a sub in a room that size...
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#618827 - 24/05/08 09:26 AM
|
|
|
An update:
After a day of farting around with Room EQ Wizard, I've come up
with the best positions for the 4 bass traps I have.
Three of them will go in 3 of the 4 corners
of the room as shown (the 4th corner is impossible because of the door), and the 4th,
which you can see freely standing, will go under the desk. These seemed to be the best
positions.
The two plots in this graph show the
room without the bass traps (red) and with the bass traps in the above positions (blue).
(I did try a whole lot of other positions, but I'll spare you the graphs-- this was the
"best", or least problematic, response.) But there's clearly room for more bass
trapping-- that trough between 90 and 100Hz is particularly disturbing.
The
scary thing, though, is the high end!!! What's worse is that I already had the auralex
that you see in the pictures in place when I did the tests!!
The duvet on the back wall wasn't there at the time of the testing, but other than that
everything was just as you see it here. I'm thinking of moving the rear Auralex panel in
front of the window, and I have a few small pieces still lying around, but clearly I need
a WHOLE lot more high-end damping, and some more bass trapping.
I can't
damage the walls permanently as we're renters, but I don't mind throwing some money at the
problem. DIY is difficult/impossible; although I was fairly at home with DIY projects in
Canada, the whole culture here is just not conducive to people doing things themselves,
which makes it really hard to source materials etc., and besides I'm without most of my
tools.
Suggestions?
|
thefruitfarmer
Joined: 01/09/04
Posts: 1672
Loc: Kent UK
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#618840 - 24/05/08 11:25 AM
|
|
|
Quote ryan mead:
Suggestions?
You can mount minitraps horizontally rather than vertically, as you have them now.
ie...with a long end against the ceiling rather than a short end.
This way you
can put some more bass traps along the ceiling / wall corners as well as the tri-corners,
which you already have.
I did this in an 8'6" cube room and it made a clearly
audible difference but less of a difference than trapping placed in the tri-corners.
I used RW5, based on Ethan Winer's advice for a smaller room, which is one of the
denser grades of rockwool.
Tricky really.....you could just get more minitraps
and then experiment with where you can position them. In your case it seems there is a
trade off between the "best" position and where they can be placed in practicality. That
said, anywhere you put them will make some difference and even if you can't get them in
the "best" position you could probably get acceptable results using more of them...
Hope this helps.
|
young david
Joined: 25/11/06
Posts: 255
Loc: Stockholm
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#618937 - 24/05/08 07:06 PM
|
|
|
If you haven't already done this, I'd start by experimenting a bit with moving the
listening position a foot or two along the lengthwise dimension. Might help with the bump
around 46 and your 90-100 dip. Failing that I'd agree that dip at 90-100 is
likely to be the biggest problem, so would think about something that will help with that
on the back wall and/or wall/ceiling apex. Wouldn't be too worried about the
top end - looks fairly smooth apart from the roll-off after 10k but if that's not the mic
then maybe your new monitors will help. I think it's normal to have a lot of narrow peaks
and troughs but as long as they're narrow it's not something that will affect your
judgement. Besides, the wavelengths are getting so small up there that if you move your
head a centimetre it will all change anyway. You have my sympathy as my room's
about this size at the mo, though it's better acoustically than larger ones I've had
before. Final tip would be once you've settled on the layout, print your room eq graph
and stick it on the wall. Helps to know that your mixes should sound slightly boomy or
thin in certain areas, and you'll start to recognise these peaks and troughs in reference
mixes. All about making the best of it. Dave
-------------------- http://youngdavid.net
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: young david]
#619039 - 25/05/08 05:00 AM
|
|
|
Quote thefruitfarmer:
You
can mount minitraps horizontally rather than vertically, as you have them now. ie...with a
long end against the ceiling rather than a short end.
I did try holding one of the Realtraps across the back wall-ceiling
interface (much to my wife's amusement) and it had less of an effect than in the corner,
where it is now. (But of course it still had some beneficial effect.)
Quote young david:
Wouldn't be
too worried about the top end - looks fairly smooth apart from the roll-off after 10k but
if that's not the mic then maybe your new monitors will help. I think it's normal to have
a lot of narrow peaks and troughs but as long as they're narrow it's not something that
will affect your judgement. Besides, the wavelengths are getting so small up there that
if you move your head a centimetre it will all change anyway.
Really? The high end sounds so much more lifeless
than in my old (bigger) room. Just sort of dull, lacking crispness, and generally worse,
like when my old room had no treatment in it at all.
The mic was a Rode NT2A in
omni mode and the preamp was one of my Fireface 800 preamps (used as a preamp only, sent
to the Tascam US122 sound card I used for testing) so I don't think the mic is responsible
for the high-end rolloff.
I've had a suggestion to put 6 GIK 244s up-- four
across the wall/ceiling interface and two on the back wall-- but I am still worried about
my top end.
-------------------- http://ryanmead.net
|
Jim Y
active member
Joined: 30/03/04
Posts: 1167
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#619136 - 25/05/08 01:59 PM
|
|
|
|
The high end trouble might be due to reflections off the TFT and desk. Try the TFT further
back and see if something absorbent (pillow, thick towels) temporarily placed over the
desk improves things.
I wouldn't be surprised if it would also improve things
if you can move the speakers further away from the window.
Would it not be
better to experiment with desk/speaker position before putting any traps in? - That way,
changes for the best with these positions will be more apparent, and you can then position
your traps to suit the room with all your equipment in place.
I have a small
room - what became apparent to me was that the acoustic effect of the objects in the room
is greater in this situation than it would be in a larger space - even changing the size
and style of my studio chair made a difference (out went the executive swivelchair - in
came a canvas directors chair).
Jim
|
JWL - RealTraps
Joined: 25/05/08
Posts: 2
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#619167 - 25/05/08 04:25 PM
|
|
|
Hi Ryan, I replied to your email, but for posterity's sake I'll include my
reply here, so that it hopefully benefits others as well. You can definitely
get good results in a room that size. Smaller rooms need proportionately more bass
trapping. The 4 you have are a good start. If you want to expand on them, I'd consider the
following: 1. More bass traps (such as MiniTraps) in the wall/ceiling corners.
The front wall looks tricky because of the window, but the side walls and the rear wall
look doable. Start with the rear wall, and then do the sides. 2. Rear wall
treatment. I'd recommend using the HF version of our MiniTrap, mounted on the rear wall
above the couch. I think you could get 3 on the wall. You'll want to space the panels out
a few inches from the wall, as described on this page: http://realtraps.com/mini_door.htm Mounting this way will increase
the overall absorption, and give you about an extra octave of bass trapping. Most rooms,
especially smaller rooms, have a bass buildup on the rear wall, so adding these will help
a lot. I recommend the HF version so that they also absorb the rear reflections. Just these 2 steps will help quite a bit. Once you have the rear wall treated and as
many wall/ceiling corners as you can fit, the next thing I'd do if you desire further room
improvement would be to replace the Auralex tiles you have with additional HF MiniTraps
mounted at the first-reflection points on the side walls and the ceiling, spaced out the
same way as the rear wall traps. You could then move the Auralex tiles to other areas of
the room (ie, the ceiling or side walls at the rear of the room, spaced out evenly in a
quasi-checkerboard pattern).
-------------------- www.RealTraps.com
www.craftedrecordings.com
|
young david
Joined: 25/11/06
Posts: 255
Loc: Stockholm
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#619218 - 25/05/08 08:32 PM
|
|
|
Quote ryan mead:
Really?
The high end sounds so much more lifeless than in my old (bigger) room. Just sort of
dull, lacking crispness, and generally worse, like when my old room had no treatment in it
at all.
The mic was a Rode NT2A in omni mode and the preamp was one of my
Fireface 800 preamps (used as a preamp only, sent to the Tascam US122 sound card I used
for testing) so I don't think the mic is responsible for the high-end rolloff.
OK, well if it's not the mic
then I guess the roll-off is a bit worrying. I guess with the Rode you should have a
presence peak somewhere high up. Plus if it sounds bad...
My point was just
that the sharp peaks and dips before 10k aren't necessarily cause for alarm - even really
well-treated rooms will have these.
-------------------- http://youngdavid.net
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: JWL - RealTraps]
#619393 - 26/05/08 01:59 PM
|
|
|
Quote JWL - RealTraps:
I replied
to your email, but for posterity's sake I'll include my reply here, so that it hopefully
benefits others as well.
Thanks JWL for the considered reply, and welcome to the SOS forums! I'll be in
touch via email.
-------------------- http://ryanmead.net
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: magicdog]
#619398 - 26/05/08 02:13 PM
|
|
|
|
magicdog
member
Joined: 25/04/01
Posts: 379
Loc: Oxford
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#619410 - 26/05/08 02:48 PM
|
|
|
Quote magicdog:
I think you would
be better off to avoid a sub in a room that size...
Second opinions on that one? Even
if the room is bass-trapped to the bejeezus? (As it soon will be.)
I would still say the same...!
If
you add a sub you will be adding hugely to the bass problems in a small room and in the
end you will need so much bass trapping, you won't be able to get into the room...
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: magicdog]
#620069 - 28/05/08 05:04 AM
|
|
|
Quote magicdog:
in the end you
will need so much bass trapping, you won't be able to get into the room...
OK I get it...
-------------------- http://ryanmead.net
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#636561 - 13/07/08 03:34 AM
|
|
|
So, I've got all this rockwool, and as I don't have room for any
superchunks, I think I'm going to apply it 15cm deep, floor-to-ceiling, wall-to-wall on
the back wall. Any thoughts on that one? rd
|
. . . Delete This
Here be Dragons
Joined: 23/06/08
Posts: 3888
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#636604 - 13/07/08 12:03 PM
|
|
|
|
well, it'll do something.....
it just won't do what you need it to do........
whaddya mean No room for superchunks??
there's ALWAYS
room for superchunks.... but you might have to think laterally to find it....
remember., ANY corner is valid , whether it's wall meets wall, or wall meets
ceiling, or wall meets floor......
and there's NO excuse really for not
filling in the upper tri-corners, where ceiling meets 2 walls ....... there's always
ways of doing things.....
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
|
Quote idris y draig:
and there's
NO excuse really for not filling in the upper tri-corners, where ceiling meets 2 walls
.......
er... a door? A
window that's the width of the room? That
seems to be a pretty good excuse to me as far as 3 of the 4 upper tri-corners go!
I could do the 4th (see the above pic; I've taken down the Realtrap for the time being),
but it would be at the expense of symmetry at the back of the room. Still figure it's
worth doing?
-------------------- http://ryanmead.net
|
. . . Delete This
Here be Dragons
Joined: 23/06/08
Posts: 3888
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#636761 - 14/07/08 08:37 AM
|
|
|
|
there's no reason you couldn't mount stuff on the door you know..... there's all sorts
of clever ways .... if using the mini-traps, then it's possible to use a hinge
arrangement so that it can be folded out of the way , either mounted on the door, so it
opens with the door, or on the other wall and arranged to fold out of the way of the
door....
(i've done this sort of thing no end of times)
note I said the upper TRI-corners....
also, look up a product called
clearsorber... it can be formed to create a transparent bass trap across the window....
or across the top ceiling to window/wall corner....
there's almost
always a way to do what's needed, but it's often not the straight forward obvious and
"normal" method...
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
|
Quote idris y draig:
if using the
mini-traps, then it's possible to use a hinge arrangement so that it can be folded out of
the way , either mounted on the door, so it opens with the door, or on the other wall and
arranged to fold out of the way of the door....
You are fuggin' brilliant! Stay
tuned...
(and yeh the ceilings are low so the door effectively interferes with
a tri-corner...)
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#638587 - 18/07/08 03:34 PM
|
|
|
Quote ryan mead:
DIY is
difficult/impossible
Scratch that.

Quote idris y draig:
whaddya mean No room for superchunks??
OK, you convinced me. 
First up for your viewing pleasure we have the patent-pending
"sofa-straddling-superchunk-stand"... stay tuned for the sofa-to-ceiling superchunk that
will call it home...

Next we have the bottom right corner
superchunk, which will also double as a base for a narrower (and less overbuilt)
superchunk that will go right to the ceiling. That narrower superchunk will be one of a
matched pair for the front wall-wall interfaces.
Here are two views of the
front floor superchunk in progress.


I'm going to do all of the prep for all of
these superchunks and make some frames for new mirror-point panels, which will incorporate
my existing Auralex with rockwool behind it. Then we're going to have a 48-hour period of
CSA (Complete Spousal Absence), during which I'll tie into the rockwool. (Koreans believe
unquestionably that rockwool causes cancer. Period.)
Meanwhile, if anyone has
any suggestions or sees anything amiss, I'd love to hear about it...
-------------------- http://ryanmead.net
|
zvalera
Joined: 28/06/08
Posts: 12
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#639411 - 21/07/08 05:28 PM
|
|
|
How do you upload your pictures as part of your post???
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: zvalera]
#639486 - 21/07/08 08:52 PM
|
|
|
Quote zvalera:
How do you upload
your pictures as part of your post???
Quick answer: you don't upload
them to this website. Find a home for them elsewhere on the web (e.g. photobucket,
flickr) and then reference them in your post using the "Image" tag, which you can find
under "Instant UBB Code".
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#640688 - 25/07/08 12:32 PM
|
|
|
Here's a big trap that will go flat on the back wall. I'm already kicking myself thinking
it's too high, because it will stretch all the way from the sofa to the ceiling, and thus
interfere with putting something along the rear wall-ceiling interface.  Oh well... maybe I can put one of my realtraps in front of it when it's done.  It's upside down in this shot, btw.
-------------------- http://ryanmead.net
|
Studio Support Gnome
Not so Miserable Git
Joined: 22/07/03
Posts: 8999
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#640767 - 25/07/08 04:36 PM
|
|
|
nice to see it coming along ryan.... yes you can mount the mini trap in front of the
flat trap... although the actual results would be difficult to precisely predict,
theoretically they will at least probably not be detrimental. glad the
pet dragon seems to have inspired you to find your diy soul
-------------------- if you don't know who i am, i aint gonna tell you.
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
|
Quote Max!:
your diy soul
My diy soul??? I'm
ready to throw my &%$#*@ jigsaw out the &%$#*@ window 
I've created a monster. Er, rather, given that "monster" and "mondo" are taken,
I've decided to call my monstrosity a "whaleTrap"(TM). Et voila:




It groans under its own weight, and
weighs well over 100 pounds! I'm going to have to build a floor stand for it.
By the way, the walls in my room seem to be concrete (or at least when I try and drive a
nail in, it bends and gets nowhere) and the ceiling seems to be some kind of fairly strong
plasterboard (I had a realtrap mounted to the ceiling, hanging simply from two wood screws
without any kind of anchor). My original plan was to hang a few things from the ceiling
(a quick plaster and wallpaper job when we move out) with the superchunks on the floor,
but now I'm thinking about getting serious with holes in the wall.
I'm really
wishing I had spec'd slightly less dense rockwool just to mitigate the whale/weight
problem somewhat.
On to the mirror-point traps (did I mention I'm sick of
jigsawing?):

Notice in the background that one of the
(two) piles of rockwool has shrunk from 4 packs to three. So I've got 87.5 percent of my
rockwool left...
-------------------- http://ryanmead.net
|
. . . Delete This
Here be Dragons
Joined: 23/06/08
Posts: 3888
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#641472 - 28/07/08 04:28 PM
|
|
|
the framing looks to be a bit heavier than is perhaps strictly necessary, which is perhaps
where some of the weight is......  other wise... nice work...
|
Ian Savage
Joined: 16/12/07
Posts: 611
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#641646 - 29/07/08 08:41 AM
|
|
|
Looking at the response graph for the room (and my acoustic engineering is rusty, years
since I had space to practice it  ), haven't
you got a resonance at 45Hz, cancellation at 90, resonance at 135, cancellation at 180 and
so on? That being the case, could you build a tuned absorber of some sort,
maybe a resonant panel type? It'd be too big to get in the room to knock a hole in the
45Hz resonance but tuning for 135Hz might have an effect? EDIT: having just
done pack-of-fag-packet calculations, a resonance of 45Hz would have a wavelength of 7.6m,
hence a half-wavelength being around 3.8m (the longest length of the room). I'll have to go back to the books to check whether tuning something to knock out the
peaks in the response would make the troughs better or worse though.
|
Ian Savage
Joined: 16/12/07
Posts: 611
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#641766 - 29/07/08 01:35 PM
|
|
|
Thinking about it the peaks and troughs at the listening position will be caused by
standing waves at half-wavelength multiples of the room's lowest resonance (in this case
90Hz); I'd guess that you'd get the opposite if you measured next to the rear wall (trough
at 45Hz, peak at 90Hz etc) so setting up a tuned absorber at 45 or 90Hz would knock out
some of the wave energy at those frequencies. http://www.soundonsound.com/sos/aug98/articles/practicalacoustic.html
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: Ian Savage]
#641767 - 29/07/08 01:46 PM
|
|
|
Quote Ian Savage:
Looking at the
response graph for the room (and my acoustic engineering is rusty, years since I had space
to practice it ), haven't you got a resonance at 45Hz, cancellation at 90, resonance at 135,
cancellation at 180 and so on?
Hmmm, according to this screenshot from the mcsquared website, it looks like you might
be onto something. ------------------------------
 ------------------------------ I'd always
interpreted these results to mean that I should be getting peaks at 45, 90, 135 etc and
troughs in between. Am I wrong?
-------------------- http://ryanmead.net
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#641768 - 29/07/08 01:51 PM
|
|
|
Oops! Looks like we cross-posted. Anyways, I have another theory about the
45Hz peak, which is that it's the resonance of the ported 8" KRK Rokits I used for the
original tests. Those speakers have since found another home.
-------------------- http://ryanmead.net
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
|
Quote idris y draig:
the framing
looks to be a bit heavier than is perhaps strictly necessary, which is perhaps where some
of the weight is...... 
Yeah, figure you're right. I actually have
been revising my plans in the direction of lighter bits of wood since I started out. The
batten boards in the whale trap were the heaviest bit-- that sliced 1.8mm plywood (sorry
folks this is a metric operation) for the frame is actually pretty light stuff.
Nevertheless, the whaleTrap ate a whole pack of rockwool, and 1m x 1m x 20cm of rockwool
is 0.5 of a cubic meter, and this stuff is 200kg/m3, so that's 40 kg (or 88 pounds) right
there.
Anyways, here's today's output:

Just like the whaleTrap, but smaller. Shall
we call them dolphinTraps? They're
meant to go at the mirror points on the wall.
The boards on the front of the
frame are sliced a bit wide, I agree, but it was all dictated by the dimensions of the
rockwool, the Auralex, etc...
btw I've been using this spray adhesive:

to affix the Auralex to the Rockwool. Here's
hoping I haven't gone too far wrong. (The guy in the hardware store was holding it and
saying "suh-pon-jee" so I guess I got my point across.) If I spray it thinly only on the
Auralex, it does nothing, but if I prime the rockwool with it and then spray it
semi-liberally on the Auralex, it grabs instantaneously and just doesn't let go.
-------------------- http://ryanmead.net
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#641802 - 29/07/08 03:20 PM
|
|
|
@idris y draig (and anyone else who cares to comment):
Help me out on this
one. I'm wondering what to do with the space behind the door. I have a couple of
ideas:
1) (OK this is your idea) Rig one of the
RealTraps so that it spans the wall-wall intersection, either at the floor or the ceiling
(sadly, the room isn't tall enough for two RealTraps, one above the other), so that it
automatically gets pushed out of the way when the door is open, and spans the intersection
when the door is closed, perhaps even acting as a weight to automatically close the door
somehow.
If I have to manually move the RealTrap in place every time I close
the door, this will complicate my relationship with the outside world when it seeks to
intervene.
There's a few restrictions here: I'd like to avoid carving up the
door at all costs, and drilling into the concrete wall if possible, because we're
tenants.
How about a diagonally ceiling-mounted RealTrap that gets pushed up
when the door opens?
2) Just build a floor-to-ceiling variant of the
whaleTrap (sans Auralex). I still have 80% of my rockwool left, after all.
3) Some combination of #1 and #2.
Thoughts?
(Thanks everyone
btw for all of the thoughtful comments from all the different angles. Hopefully I'll end
up with a frequency-response curve you could use as a billiards table.)
-------------------- http://ryanmead.net
|
Ian Savage
Joined: 16/12/07
Posts: 611
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#641809 - 29/07/08 03:53 PM
|
|
|
Quote ryan mead:
[ I'd
always interpreted these results to mean that I should be getting peaks at 45, 90, 135 etc
and troughs in between. Am I wrong?
Not at one steady position, where you'd get exactly what you measured - a peak at
one resonance followed by a trough at the next and so on.
If you draw the
diagram showing the sound pressure distribution in a standing wave you'll find that for a
half-wavelength standing wave (in this case circa 45Hz) the pressure is at a maximum in
the centre of the room and zero at the walls (where the particle velocity is at its
maximum). For the next resonance up along that room axis (90Hz, in our case) you can fit
TWO half-wavelengths in the room, so at the same position (the centre of the room) the
pressure is now zero whilst the velocity is at a maximum. For the next one you'll get
three half-wavelengths packed in there, so at the centre of the room you get a pressure
maximum (peak) again, and so on.

After a few hundred Hertz these generally cease to
matter too much, as general diffraction of the smaller wavelengths makes it much harder to
set up a standing wave.
I reckon behind the door's the perfect wall for a
tuned membrane absorber, like wot I said before (there's a
link to a SoS article on them in my last post, in case you missed it!). Tune it to 43-45Hz
(if your room measurements are accurate be as anal about the exact frequency as you
want!), knock a big chunk of the standing wave energy out of the room and you'll find a
greatly flattened response or your money back
|
thefruitfarmer
Joined: 01/09/04
Posts: 1672
Loc: Kent UK
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#641864 - 29/07/08 06:23 PM
|
|
|
Quote ryan mead:
1)....
How about a diagonally ceiling-mounted RealTrap that gets pushed up
when the door opens?
2) Just build a floor-to-ceiling variant of the whaleTrap
(sans Auralex). I still have 80% of my rockwool left, after all.
3) Some
combination of #1 and #2.
Thoughts?
I would go for something floor to ceiling on
a hinge that gets pushed open when the door is opened and is pulled back when the door is
closed.
I don't think you can avoid drilling holes in the walls but a vertical
trap will need less support than a horizontal trap across the ceiling wall join.
Maybe you could put a wheel on the bottom of a vertical trap? This would take some of
the weight.
I suspect it is easier with your inward opening door rather than
the outward opening door I have in my room.
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
tuned traps now?
[Re: Ian Savage]
#641953 - 29/07/08 11:45 PM
|
|
|
Quote Ian Savage:
I reckon behind
the door's the perfect wall for a tuned membrane absorber, like wot I said before (there's a
link to a SoS article on them in my last post, in case you missed it!). Tune it to 43-45Hz
(if your room measurements are accurate be as anal about the exact frequency as you
want!), knock a big chunk of the standing wave energy out of the room and you'll find a
greatly flattened response or your money back
Well, you really got me thinking about
this one. I originally dismissed the article seeing as it was written in 1998 and I've
gleaned that the conventional wisdom these days is not to go for tuned traps, but now that
you've shown me the pattern to the peaks and troughs it seems painfully obvious. 
Of the two types of tuned trap mentioned in the article, the panel absorber seems to be
the obvious one (or is it?).
A few questions:
1) Would the door have
to be closed for the thing to work effectively? (I'm guessing "yes" on that one.)
2) Would a piece of 8mm plywood (I have it on hand) be appropriate for the
resonant surface (assuming I do the math)? If not, what else would you suggest? (Being
in South Korea makes it all the more difficult to source strange/rare/obscure
materials.)
3) Assuming I make a box about 8 inches by 3 feet by 8 feet
(tweaked to satisfy the equation) and just stand it in the corner, is there any merit to
not bracing the back with plywood, and maybe standing the box an inch away from the wall,
to get another resonant surface happening? Or would this complicate the math?
-------------------- http://ryanmead.net
|
thefruitfarmer
Joined: 01/09/04
Posts: 1672
Loc: Kent UK
|
Re: tuned traps now?
[Re: ryan mead]
#642010 - 30/07/08 07:59 AM
|
|
|
Quote ryan mead:
....
the conventional wisdom these days is not to go for tuned traps.....
Not without good reason.
Nearly everyone uses broadband absorbers.
Less space, easier to build,
cheaper, portable, difficult to get it wrong.
|
Ian Savage
Joined: 16/12/07
Posts: 611
|
|
Quote thefruitfarmer:
Quote ryan mead:
.... the conventional wisdom these days is not to go for tuned traps.....
Not without good reason.
Nearly everyone uses broadband absorbers.
Less space, easier to build,
cheaper, portable, difficult to get it wrong.
...but worth it when it's a specific frequency causing most of
the problems, surely? A tuned-membrane trap won't take up much more space than a broadband
bass trap (takes up less than one that goes appreciably low), they can't be that hard to
build, as I made one once - hardest
bit was getting it properly sealed.
Okay, tuned absorbtion needs a bit more
design work, but it's nothing someone with Maths and Physics GCSEs couldn't handle.
|
Doublehelix
Joined: 04/12/02
Posts: 4162
Loc: USA
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#642122 - 30/07/08 12:01 PM
|
|
|
|
I saw a thread once where someone built a corner trap in a frame with wheels, and then
they could move it in and out of the way of a door when needed. Similar to the frames you
have already built for your corner traps, just with casters.
-------------------- James
"Never interrupt your enemy when he is making a mistake" ~Napoleon Bonaparte~
|
ryan mead
Joined: 19/06/05
Posts: 1375
Loc: Seoul
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#642376 - 31/07/08 01:34 AM
|
|
|
 A
visit from the king of studio renovation threads himself! Hi James!  If I devise something movable for the behind-the-door corner, it's going to have two
(not insurmountable) restrictions on it: 1) As my original sketch shows, the
sofa's going to take up all of the space on the back wall not required for the door to
open, so the movable space has to live in the small area behind the door when it's
open. 2) I would like something that gets out of the way automatically when my
wife opens the door so that she doesn't think I've gone into bar-the-door-shut,
goddammit-I'm-creating-don't-bother-me mode just because I've put a bass trap in place. On the basis of a few Studio SOS's I've read, part of me is predicting that the
bass response will be more even with the door open anyway.  So here's last night's accomplishment. It's for the ceiling mirror position. (The
"flyingFishTrap"?) I'll hang it about 10cm below the ceiling, and maybe throw some white
Christmas lights up there.   That eats up all of the Auralex I
originally had on hand. Rockwool remaining: 75% Jury's still out on what to do
behind the door. Meanwhile, today is superchunk day.
-------------------- http://ryanmead.net
|
Doublehelix
Joined: 04/12/02
Posts: 4162
Loc: USA
|
Re: moving my studio to a smaller room
[Re: ryan mead]
#642384 - 31/07/08 02:35 AM
|
|
|
Quote ryan mead:
A visit
from the king of studio renovation threads himself! Hi James!
Wow! That is some welcome!
(And completely undeserved, I am a total and complete amateur struggling to complete his
little hobbit hole!)
I have been following your thread, I have just had very
little to offer in the way of advice, you are doing a great job on your own! I love the
look of the traps, and I love your comedic writing style! Wanna give me hand with some jig
saw work I have coming up??? 
Quote ryan mead:
I
would like something that gets out of the way automatically when my wife opens the door so
that she doesn't think I've gone into bar-the-door-shut,
goddammit-I'm-creating-don't-bother-me mode just because I've put a bass trap in place.
Great one! Yeah, I feel
your pain man! And you never liked her mother either, and that belt she was wearing last
night made her butt look huge! How could you??? And now, you want to lock yourself up in
your little kingdom and totally ignore her... etc... You are a cad, sir!
Been
there, done that, got the T-shirt!
Quote ryan mead:
On the basis of a few Studio SOS's I've
read, part of me is predicting that the bass response will be more even with the door open
anyway.
I
actually did some testing in my CR, and found that it did indeed make a bit of a
difference, but not much, and it took away some of the room symmetry as well.
The "automatic" bit is going to take a bit of work on your part... good luck! I am
anxious to see what you come up with.
-------------------- James
"Never interrupt your enemy when he is making a mistake" ~Napoleon Bonaparte~
|