Studio Set-Up With Photos - Need Assistane Please!

[soundmagus]

Originally Posted by DanDan

Best to measure with single speaker driven. Do both as well, but the primary measurements should be with one.
Also smoothing....all in all if you read this you will probably take do measuring quite differently.
LF response is the biggie. View it 30-300Hz.
Full range gives an indication of tone, average the two individual graphs L and R and use smoothing to make sense of the HF.
You want a nice bassy curve similar to that at Understanding RTA over at StudioTips.com.
Use the Eq on the ADAM's to achieve this HF roll off and LF boost.

You will have extreme flutter between that tiled floor and the ceiling. Full ceiling cloud or partial with thick rugs on the floor where there is no cloud overhead.
Probably no point to traps behind the speakers RealTraps - Front Wall Absorption

I suggest you start with the biggest problem, lack of bass. Find out what is causing it, which will tell you how to treat it. Playing sine waves at the troubleseome frequencies is great for this. Use the Sig Gen in REW and turn on Frequency follows cursor. Slide the cursor over a big null. Move about the room to find the peaks and nulls. This should advise you very clearly where to place Bass Traps.
DD

DD

DanDan - I am taking your advice and trying to deal with the low end first.

As expected when i use the REW Sig Gen with Frequency follows cursor i hear lots of bass in the corners. I will put 2 traps (one on top of the other) of the R60 in all 4 corners (although the ones in the corner where the door is are going to have to be on feet so i can move them - what a nightmare) and see what happens to the measurment.

When i walk around the room, for instance, right behind my listening position i have a null, the bass disappears completely, how do i treat htis as its in the middle of the floor?

I have to say i new there was a problem with bass, in the fact that i couldnt hear any :O so i am going to really concentrate on this and try to do the best i can with the traps i have.

Is it due to the amount of glass that i am having a large lack of Bass?

thanks

Mark

[DanDan]

Not dumb Mark, perhaps a little blind!
From the primer

For Frequency Response and ETC drive one speaker only. (Or 1.1 with the Sub)
For Waterfalls and Decay measurements drive both or all speakers. This is more likely to get all the modes going. A Y lead may be needed, I use a Mono switch on my controller. You could drive the modes even better by placing the speakers in the floor tricorners.

DD

[soundmagus]

Do`h :P

About the use of the single speaker DD, shall i place it in the middle of where my steereo field would be ?

Mark

[ritelec]

Originally Posted by soundmagus

DanDan - I am taking your advice and trying to deal with the low end first.

i hear lots of bass in the corners. I will put 2 traps (one on top of the other) of the R60 in all 4 corners
thanks

Mark

Maybe go straight to the thicker fluffy stuff. Although if your just stacking made traps you could check first then maybe use them elsewhere.


Wall behind the Loudspeaker Cancellation
(also click on flush mount)


Thanks for the link Dan

[soundmagus]

Originally Posted by ritelec

Maybe go straight to the thicker fluffy stuff. Although if your just stacking made traps you could check first then maybe use them elsewhere.


Wall behind the Loudspeaker Cancellation
(also click on flush mount)


Thanks for the link Dan

Hey Ritelec, i dont have, thicker, fluffier stuff lol so i am not sure what you mean.

Thanks for the link i will check it out

[DanDan]

Mark, nulls are the result of a cancellation caused by reflection off the walls.
If you weaken the reflection you weaken the null.
So when playing sines, look for peaks at places where you can place traps.
You will find corners are a home to most modes, but do not when a modal peak covers the whole wall.

Your current corner trapping plan is good. A minimum, but good.

Measure FR and ETC using one speaker in it's likely final position.

Measure LF FR, Waterfalls, with each speaker and both.
Look out for L R differences, there will be with that window at the side.
Both driven gets more modes going and is closest to how it will be, for LF.
You could place a speaker in a corner on the floor, mic at the surface in the middle of the opposing wall. This would show up the room's modal response best. Interesting and may show some surprises, but it is not how things will be when the speakers are actually in place.

DD

[soundmagus]

Right DanDan, thats you got me on the understanding road again.

Tomorrow i will use L then R speakers in their final positions and make measurments.

I will walk around the room in all 3 (L, R and L/R) and try to put reflection killers where i hear the most bass.

Then take further readings,

Thanks guys,

Much appreciated as always

Mark

[soundmagus]

Hi guys,

I have now started to put up uthe traps in their permanent positions and i would like your feedback on the results so far.

The traps i have tested so far are pretty much standard positioning. By this i mean in 3 corners and 2 first reflection points and one on the back of the door.

I havent finished corner 3 yet as i need to make a new frame due to the different height of the roof in that particular corner.

Also the ceiling/front wall trap hasnt been put up yet.

You will also notice the weird method (using the wire cable) i have had to impliment to hang the ceiling cloud. This was due to the ceiling being made of ply wood and hence not being strong enough to hold traps on its own.

This has left me with a new puzzle, what do i do about the side wall/ceiling traps as i cant put them there due to the cables being attached to the wall in that space.

I havent put anything on the back wall to ceiling or back wall reflection points yet either, this will be done in the following days.

I am also going to put a trap in the corner over the door.

I also have another 2 traps for reflections which i will place on the side walls at null points i find.

So to make it plainer, i will list the questions i have and need help with below, many thanks for your help and please check out the photos and let me know if you have any suggestions for remaining trap placement etc.

BTW The measurement pictures are as follows -

Blue - Empty Room (no treatment)
Green - First 2 CLoud Traps
Pink - 2 Side Reflection
Yellow - Corners and Back of Door

1. Where do i put the side wall, ceiling/wall traps now that i cant angle them due to the cables being there?
2. Should i put a trap on the wall to the left of the door?
3. The trap i put above the door in the corner leaves a huge gap
on each side of it, is this an issue?
4. When i move around the room when using the freq gen in REW at specific freqs, when i hear that the bass in MISSING do i put a trap there? or is it when the bass is BOOMY that i put a trap on the wall?

Many thanks for your help as always,

Mark

[soundmagus]

I just realised i didnt do the reading with single speakers, i will do them today lol

[localhost127]

would it be possible to stack the corner traps horizontally (48"wide, 24" tall - and stack to the ceiling) in the corner where the couch is? it looks like you have room to do such.

[soundmagus]

localhost127: thats just not possible, it would take all of the remaining traps i have to do so which means no back wall treatment, no treatment above door in corner, no treatment on side wall ceiling/wall and no front wall ceiling/wall treatment.

Why are you thinking this?

thanks

Mark

[localhost127]

Originally Posted by soundmagus

localhost127: thats just not possible, it would take all of the remaining traps i have to do so which means no back wall treatment, no treatment above door in corner, no treatment on side wall ceiling/wall and no front wall ceiling/wall treatment.

Why are you thinking this?

thanks

Mark

my apologies - i did not know you were working with a limited number of broadband absorbers.

laying the traps horizontal (48" wide) spaces the insulation further from the boundary - which should result in higher effectiveness (since we are dealing with velocity-based, porous absorption).

also, might i suggest making your 'side wall' gobos horiztonal as well vs the vertical placement they are now? do you think you will likely move your listening position up and down, or do you feel you may slide your chair back and forwards towards the desk? if the latter, by placing the panels horizontal (48" wide vs the 24" wide they are now), you will have a larger sweet spot for moving about on that axis. just a thought

[soundmagus]

localhost127 - the horizontal wall absorption is a thought but i had been advised the following by john (jhbrandt)

"Mark,

Center the panels vertically at ear height - or at the acoustic center of the speakers (these should be close to the same)

Cheers,
John"

Also i have another 2 traps of the same size to add to the side walls which i think will take care of all reflections there (i hope so) but i am definataly not adverse to making them horizontal if they will improve my situation.

The back left corner is like a HUGE bass speaker, when i stand on top of the couch the bass there almost rips my head off so i guess i need more absorption in that part of the room. I have added another, smallr trap above the one there now and will attach another one to the wall to the left of those, i might use this one horizontally (what do you think?) however if i put it vertically and also anothe ron on the ceiling/wall corner then that might do the job.

thanks and any more advice always welcome

Mark

[soundmagus]

Empty Room ^^^



Treatment So Far ^^^


Ok i have added the bass trap to the back corner so that it now is also floor to ceiling.

I have made another measurement with this.

Can someone help me understand what i am seeing and the best way to resolve the obvious "lack if bass" issues and the Peaks.

In the first picture we have the empty room with its obvious peaks and nulls. (blue)

The second picture is with all the bass trapping i have put in place so far with the major peaks and nulls noted (PINK. - nulls in red peaks in black).

Now with my limited knowledge of acoustics here is what i "think" i am seeing:

The use of the traps have smoothed out the peaks at 233Hz and 208Hz.(blue)

The peak at 160Hz has been smoothed out a little but moved to 155Hz.(blue)

There seems to be a new LARGE null at 135.1Hz (pink) although the peaks at 116Hz and 107Hz (blue) seem to have been smoothed out somewhat but with a new smaller peak at 103Hz (pink).

Below this the peaks and nulls are pretty much the same alhtough i think they have actually gotten worse (pink) with the trapping than in the no trapping scenario (blue).

I still havent taken measurements with single speakers yet as i am not sure what i am supposed to do with them. DO i just take readings as normal and try and listen for nulls and peaks on each side of the room and ad trapping accordingly?

I have walked around the room and the back left corner (even with the trapping - although there is nothing on the wall directly behind my head or the ceiling/wall corner yet) is still like a huge bass magnifier which is vert very extreme.

So does this look like an improvement?
What can i do about the bass issues?
Is it even possible with this small room to treat those lower frequencies?

To be very honest i am starting to feel a bit overwhelmed, i am not sure if i am doing things correctly anymore, its all getting a bit overwhelming.

Any and all guidance in how to get this room finished off so i can get some work done would be great.

I still have 2x100mm R100 left which i am going to use for the wall/ceiling corner final cloud trap and the other can go wherever its needed but i was thinking back wall behind my head.

I then have another 4 slabs of R60 (50mm) which i was going to use to create 2 100mm bass traps and use them where ever they are needed but definately one above the door and maybe break the other one down to make smaller traps for the side room ceiling/wall corners ( ishould be able to squeeze somethign in-between the cables there). However i could create 4x50mm traps and use them instead in the positions above.

I really do appreciate everyones help and hopefully i can get this room completed this week to the best of my ability and move forward from there. I am feeling a bit terrified that all of this hasnt helped with bass handling at all and considering all i create/work with is Dance music, especially bass heavy stuff i am having kittens lol.

many thanks,

Mark



Front Wall with corners trapped but no ceiling/wall corner trap yet



Back wall with trap on door and corner trapped but with no back wall or ceiling/wall corner traps yet.



The problem caused by the use of cables to hang the cloud. The ceiling/wall side corners are a problem, can i just put smaller traps between the cables for the ceiling/wall corner?



The problem caused by the use of cables to hang the cloud. The ceiling/wall side corners are a problem, can i just put smaller traps between the cables for the ceiling/wall corner?

[DanDan]

Mark is it the pictures or the sound you find frustrating?
As you are not using the measurements in any sensible way, why don't you just stop measuring. ETC has no meaning with two speakers.
Us recording people are used to making judgements by ear aren't we?
I am inclined to think that the HF clatter and flutter echo in the room is greatly diminished. Does it sound better now?

If you do wish to continue with measurements please do single speakers only. Even better post the mdat file here.

Use the mirror trick to find a whole area where reflections of the tweeter are visible from an area of seat positions, back and forward. Horizontal traps will catch a much larger span back and forward. Same is true of the cloud, looks like you may be OK there but check with the mirror. Pluck those hanging wires to see if they boom like bass strings. Damp them if they do.

The Bass problem is nasty. I am assuming a concrete floor. I see the windows. What are the rest of the walls and ceiling made of?

Your untreated waterfalls do not show the usual modes sticking out.
Hard to show an improvement in the modes if they weren't the problem to begin with eh?
You could have the opposite problem to most of us, i.e. very little modal support of the LF. A room is like a musical instrument. It must be big to do bass well. It must have rich resonance distributed evenly with no one sticking out. Your room is too small to do bass well. It has very little resonance due to the windows and possibly light walls. In the midst of this we have some extremely hard surfaces causing strong build up and very destructive reflections.

Tough one.
The most powerful tool is positions of speakers and listener. Try some moves. Use the software to see if there is improvement or not. If the room is as I say, too small, bass leaky, but with some very solid boundaries, then you will need more bass for a start. Bigger speaker or a sub. Or even two subs.

DD

[soundmagus]

Mark is it the pictures or the sound you find frustrating?

Well the pictures, the bass is god aweful and i dont see any improvement from the empty room here.

As you are not using the measurements in any sensible way, why don't you just stop measuring.

I thought i was using the measurments in a sensible way, IE looking for peaks and nulls and trying to figure out what to do about them.

ETC has no meaning with two speakers.

Us recording people are used to making judgements by ear aren't we?
I am inclined to think that the HF clatter and flutter echo in the room is greatly diminished. Does it sound better now?

Yes the room definataly sounds better, but due to all the measurment stuff i am unsure as to wether i am hearing bass too much in one position or not enough in another.

If you do wish to continue with measurements please do single speakers only. Even better post the mdat file here.

So i do single speaker readings as above (spl/phase, impulse and waterfall). Would this mean i have to post an mdat file for both left and right?

Use the mirror trick to find a whole area where reflections of the tweeter are visible from an area of seat positions, back and forward. Horizontal traps will catch a much larger span back and forward. Same is true of the cloud, looks like you may be OK there but check with the mirror. Pluck those hanging wires to see if they boom like bass strings. Damp them if they do.

The Bass problem is nasty. I am assuming a concrete floor. I see the windows. What are the rest of the walls and ceiling made of?

Tiled floor, concrete walls front back and sides where there is no glass. The roof is plyboard covering what i am not, sure but there is a substantial gap in the roof, enough to walk in.

Your untreated waterfalls do not show the usual modes sticking out.
Hard to show an improvement in the modes if they weren't the problem to begin with eh?

You could have the opposite problem to most of us, i.e. very little modal support of the LF. A room is like a musical instrument. It must be big to do bass well. It must have rich resonance distributed evenly with no one sticking out. Your room is too small to do bass well. It has very little resonance due to the windows and possibly light walls. In the midst of this we have some extremely hard surfaces causing strong build up and very destructive reflections.

Tough one.
The most powerful tool is positions of speakers and listener. Try some moves. Use the software to see if there is improvement or not. If the room is as I say, too small, bass leaky, but with some very solid boundaries, then you will need more bass for a start. Bigger speaker or a sub. Or even two subs.

So in regards to the monitor/listening set-up this is what i have at the minute.

The monitors are 68.5 inches from each other and the converge 2 feet behind my listening position which is 38% of the length of the room from the front wall.

I know this isnt an equilateral triangle with my head but i read somewhere you can have the convergence here and it means that i can have my monitors wider apart which stops me from having issues with the monitors blasting sound into my screens.

However 38% from the BACK wall is pretty much spot on where the audio converges and would mean i would be sitting at the equilateral triangle point, would this be better or should i just test with moving the monitors forward and backwards?

I used the mirror method for first reflections on the side walls and the roof (cloud). As you can see the cloud isnt complete yet and there is also nothign on the back wall, do you think this will make any difference? and what about the side wall ceiling/wall corners? should i try and force some trapping in there also? The wires dont work like bass strings, they are relatively loose enough for that not to occur?

Should i also add trapping to the back wall and the corner above the door? and do you think i should change the side reflection traps to horizontal instead of how they are now (vertical)?

Sorry for all the crazy questions, and i thikn there has definately been an improvement the biggest problem now is that i am unsure of the bass response wethe ri am hearing too much or not enough.

thanks so much for your help,

Mark

[DanDan]

It is difficult to get into this, with no disrespect whatsoever intended, you are missing the understanding of many basic principles.
I know this from your questions.
You really need to have read at least the Master Handbook of Acoustics to engage in meaningful discussion here.

REW is very powerful and does things differently from the way us Mac users are familiar with. A measurement is taken and saved for the Left speaker. Within the same session or document, another is taken and saved for the Right. And so on, there can be many within the one doc.
There is another command called Save All Measurements. I find this confusing, I always assume Save, saves what I am looking at. Persist and make sure your L and R measurements are definitely saved into the one mdat file.
We can then view them compare them, see them as waterfalls ETCs, whatever.
These graphs are all just different ways of viewing the measurement which is really an Impulse Response.

I don't know what plyboard is or what it is covering. However it sounds floppy! So I am going to assume bass will pass through it. In which case, you have enough cloud at the front. Do more or carpet at the back if you have flutter. Thin is fine for flutter.

In order to treat you have to identify the cause. In your case the overall cause appears to be lack of modal support. Strong assymetry LR and Front Back and Vertically caused by LF soft walls facing hard ones.

Move house! Or get into headphones.

Try moving one speaker towards the front wall, measure, better or worse.
Settle on the least bad position. Don't be afraid to almost touch the wall.
Same for the side wall.
Repeat for the other speaker.
Now try some tweaks with the two together to see if they fight, or if there is any further improvement possible.
Now try your listening position. Back and forward, view the LF curves, better or worse.

There is no need for us to see and discuss all the little interim measurements. Better or worse, settle on the least bad.
Some people just run pink noise, view the LF on an RTA and move the speaker about while watching the screen.

The benefit of these simple techniques is that they treat by doing.
If you want to go the analysis route you really need to be able to identify Modes from SBIR and LBIR. There may be no advantage to the high brow. It is not necessary to read music to play it well.
DD

[Salpion]

Hello everyone!



I am in the process of building a recording studio above my home residence, which is also under construction. I think I have made a big mistake and I need a kind of undo-advice from you. The thing is I invested more into sound insulation on the external walls of both control and live room (to avoid complaints from my really crabbed neighbour! ) instead of the internal wall between the two rooms.



External walls: regular brick (4 inches / 10 cm) + 2 layers of polysterine (4 inches / 10 cm) + regular brick (4 inches / 10 cm) + rockwool (2 inches / 5 cm) + 1 layer of half-inch plasterboard.



Internal wall: regular brick (10 inches / 25 cm) and that's it!!!


Since the internal wall is probably quite poor for insulation, I am thinking of adding to the existent 10-inch brick wall a 4-inch brick wall (with 4-inch air space in between) + 1 or 2-inch rockwool + 1 layer of half-inch plasterboard. That's a total of 19.5 or 20.5 inches (49.5 or 52 cm).



My questions are:



1. Taking for granded that 52 cm is the maximum sum of thickness I can get (or even less if possible) for my internal wall, is there a better combination of the materials above or different calculations of their thickness?



2. What is the ideal thickness of air space between the two brick walls in my case?



3. Is there any sound insulating material to use (instead of having an air space) that would have given me a better result? What about polysterine?



4. What kind of rockwool should I look for to get effective sound insulating and absorbing conditions? Any helpful links online? How much thickness should I go for?



5. Is there any other material I could use to replace rockwool for more effective sound insulation or acoustic absorption?



Thanks a lot for taking the time to read about my concerns!

[soundmagus]

Maybe you should have started a seperate thread!

[Salpion]

OK, thanks! But how do I start a new thread? I am obviously new in this!

[soundmagus]

no Problem

goto the forum you feel is most relivant to your question and select new thread.

Studio building / acoustics - Gearslutz.com

Studio acoustics (link above) being the obvious one for your question.

Mark

[Salpion]

Thanks a lot!

[Salpion]

Dear Mark,

I have just started a couple of new thread (as you advised me to do).
Could you have a look on them and tell me your opinion?

1. Poor internal wall - I need an undo-advice!

2. Shall I get rid of roller-shutter boxes?

Thanks again,
Kyriacos.