Reducing noise leakage to adjacent rooms

[Emre Hanli]

Hello bass people,

I'm moving to a new apartment. I have two rooms to choose from to put my studio in, one big and one small. An isolation professional came to study the place. Since it's an apartment building, he suggested a floating room solution and the price he worked out for the small room was around 4.5k. I don't have a budget for that now.

I installed an SPL meter on my phone and when I'm playing the level goes up to 95db at times and usually under 90db. Do you think it'd be possible to use some form of insulation other than the floating room method to bring it down to acceptable levels for the neighbors? I know acoustic treatment and isolation are two different things, so I'm not looking at acoustic tiles here. I can consider building a second wall with some sort of noise reduction material and covering the ceiling that way too.

BTW, one of the rooms I can pick shares only the ceiling with a neighbor and the other has a shared wall plus a ceiling. Below my apartment is the parking lot.

 

[EastCoastThump]

When low-end is involved, the really effective sound reduction techniques available for apartment tenants are spendy and eat space. $4.5K actually seems pretty reasonable to me for a contractor-built floating room.

If that's out, how much air do you need to push? IOW, is the studio for individual practice, group rehearsals, or recording—and how crucial are a pushed cabinets and acoustic drums to your goals?

If the SPL comes from using just a bass rig for solo practice, I'd wean myself from the amp around the apartment. Bassists now have a lot of good modern options for preamp/DI—including some with quality amp/cab/mic sims—into the mixing board or headphone amp.

If you absolutely need the sound of a pushed bass cab for recording, you can reduce mechanical coupling by putting an isopad underneath, using and amp stand, or putting amp on stand and isopad b/w floor and stand's contact points. Reducing the cabinet's low frequency acoustic spill will be harder. For apartment living with neighbors sharing walls, you could put the cab in an isobox (essentially a mini room-within-a-room), but at that point, I'd be back to thinking about DI or DI/preamp solutions and DAW plug-ins.

If the studio's for group rehearsals (esp. w/ acoustic drums), that's tougher still on a minimal budget. For rehearsals, you can build platforms that rest on acoustic decouplers to address mechanical coupling of amps and drum kit, but when distance and mass aren't already on your side, sound reduction for high SPL sources requires a no-fooling budget.

And for recording? If you start with a small space that you need to rework for to reduce transmission to adjacent living space, then even with an ample budget, physics works against you ending up with a decent sounding room for recording acoustic drums. I'd shift to edrums or look for a different space.

 

[Emre Hanli]

Well, there's no acoustic drums involved. It's only my bass, amp and cab that exceeds the limits. There's an occasional driven guitar sound too, but it doesn't go low enough to be a problem. I had always used the DI route when recording. Now I want to go into the miced cab territory but looks like it's not an option.

Our currency is very weak against the dollar these days and all the materials in question are imports. 4.5k usd makes 25k trl and that's a huge number to spend within a rental apartment for me. Would be a different story if the place was mine though. I thought maybe I could go around this problem but looks like anything except the floating room will be a failure.

 

[seamonkey]

Bass is incredibly hard to isolate. Floating the room may not give you what you need.
Bass goes right through so called isolation pads. They don't work. At best the tilted pads point the cab at your ears so you hear the mids/highs better and you're fooled into thinking the bass is less.

You could look into some active/noise canceling methods like they do in high end cars but it won't be cheap.

Headphones or In ears are a good thing to get use to these days. They are everywhere and some excellent recordings being done using them.

 

[saabfender]

I would not rule out acoustic tiles on the ceiling. That will help for certain. Any energy absorbed is a win. Blankets over the walls, gobos, etc. Bass is tremendously hard to contain, though, due to its lack of directionality (?) and wavelength. But the bass frequencies are not the entirety of the problem. There's plenty above half wavelength of any dimension of the room in a bass guitar and certainly in your playback device you are playing with.

Never set your amp on the floor. Put it on something.

 

[EastCoastThump]

Bass is incredibly hard to isolate. Floating the room may not give you what you need.
Bass goes right through so called isolation pads. They don't work. At best the tilted pads point the cab at your ears so you hear the mids/highs better and you're fooled into thinking the bass is less.

You could look into some active/noise canceling methods like they do in high end cars but it won't be cheap.

Headphones or In ears are a good thing to get use to these days. They are everywhere and some excellent recordings being done using them.

Agreed on thinking about headphones or IEMs. But just to avoid confusion for the OP or later readers, let's unpack the few different kinds of technical issues here:

• Isolation pads are meant to decouple a source from the floor to reduce mechanical resonance. For an installation like the OP is discussing, an isolation pad (or cab stand with isolation pad underneath) won't much change the way the bass sounds in the room. (If he were setting the cab directly on a hollow wooden stage or somesuch, then an iso pad could make a significant difference in the perceived sound at his playing position; but if that's how his apartment is constructed, his noise abatement efforts are pretty much doomed.) Instead, an iso pad would reduce the energy passed from the cab's mechanical vibration directly to the floors. In that way, it'll help calm what the neighbors hear. Acoustic energy will still bounce around the room, passing through walls/floors/ceilings and physically exciting them. So even a theoretically perfect iso pad alone won't soundproof a room. And a real world iso pad doesn't stop 100% of the mechanical coupling. But it'll help.

• As a separate issue, tilting the cab toward the player usually helps keep SPLs under control in rehearsals or on stage just b/c the player turns down. And lowering SPLs in the OP's studio room would help the neighbors. Except his purpose is to record cab tones—in which case he'll need to drive the cabs however loud he has to in order to get the tone he wants to record.

• "Noise cancelling" tech is moderately effective at reducing droning background noise for a fixed listening point; it's not very good for live music, and it doesn't at all address the SPLs for neighbors.

 

[seamonkey]

Agreed on thinking about headphones or IEMs. But just to avoid confusion for the OP or later readers, let's unpack the few different kinds of technical issues here:

• Isolation pads are meant to decouple a source from the floor to reduce mechanical resonance. For an installation like the OP is discussing, an isolation pad (or cab stand with isolation pad underneath) won't much change the way the bass sounds in the room. (If he were setting the cab directly on a hollow wooden stage or somesuch, then an iso pad could make a significant difference in the perceived sound at his playing position; but if that's how his apartment is constructed, his noise abatement efforts are pretty much doomed.) Instead, an iso pad would reduce the energy passed from the cab's mechanical vibration directly to the floors. In that way, it'll help calm what the neighbors hear. Acoustic energy will still bounce around the room, passing through walls/floors/ceilings and physically exciting them. So even a theoretically perfect iso pad alone won't soundproof a room. And a real world iso pad doesn't stop 100% of the mechanical coupling. But it'll help.

• As a separate issue, tilting the cab toward the player usually helps keep SPLs under control in rehearsals or on stage just b/c the player turns down. And lowering SPLs in the OP's studio room would help the neighbors. Except his purpose is to record cab tones—in which case he'll need to drive the cabs however loud he has to in order to get the tone he wants to record.

• "Noise cancelling" tech is moderately effective at reducing droning background noise for a fixed listening point; it's not very good for live music, and it doesn't at all address the SPLs for neighbors.

No - I'll stand by that Iso pads do nothing. Hollow stage or not.
Sound radiates 360 in the low bass region. And this low freq sound goes right through an iso pad. Stand behind an iso pad and listen as the lows go right around it.

Mechanical vibration is something pad sellers made up. A HPF would control mechanical vibration - which is not sound. Most stress from the driver would be front to back as the cone moves in and out, but sound comes out 360 still.

Look up cardioid subwoofer for how to control where low frequencies go.

Real Bass traps are great for in room treatment. They could help with resonant build up in the room which would leak out, but the engineer would hear and measure the resonance and turn the bass down. I do recommend measuring the room before treatment but begin with treatment first then EQ.

 

[silky smoove]

This is an apartment? As in a place that you're renting, not owning? If that's the case I would not throw money away in construction solutions. What happens when you move out? All of that money gets flushed down the toilet.

Generally speaking, apartments and even condominiums do not mix well with studio work unless you have a massive budget. Get yourself a good modeling system like a Fractal, Kemper, Helix, etc. or a software platform like Bias, some really nice headphones and focus on making music without annoying your neighbors.

 

[EastCoastThump]

No - I'll stand by that Iso pads do nothing.

No offense intended, but you're confusing two different issues. Iso pads aren't meant to be bass traps or room treatments.
It's true that they don't stop low frequency acoustic waves from radiating from your cab, but that's not why you'd use one.

If you've ever leaned on a bass cab while you're playing (or had a Special Friend™ who likes to perch there while you practice), you'll know that bass cabinets vibrate. A lot. If the OP's apartment is built less like Fort Knox and more like a typical apartment complex, that mechanical energy is liable to get passed along the floor joists and annoy the beejabbers out of the near neighbors.

If you have children who have woken you in the early hours of a post-gig morning by thumping an object (a heel, a ball, a book, a sibling, etc)
against a wall even a couple rooms away, you'll know that acoustic spill isn't the only isolation challenge here.

A lot of apartment dwelling drummers found this out after making an expensive move to e-drums: even the kick pedal hitting a "silent" kick tower is capable of provoking calls to building management, the police, or Guido & Lefty's Problems Solved LLC. The solution there is to build a platform for the drums and isolate it with damping material between platform and floor—from purpose made isolation disks or pucks to low-rent tennis balls. IOW, a drum-sized iso pad.

Again, just to clarify; not to promote this as a likely solution in the OP's case. As I said in post #2, I'd be looking toward DI/preamp and/or plug-ins in the situation he describes.

 

[Emre Hanli]

Thank you for all the replies. I'll stick to low volume monitoring and headphones at night. I'll try to get help from the same person for acoustic treatment and see how it goes. Still hoping I can play bass through a small combo and get away with it. I'll see what happens...

 

[JeezyMcNuggles]

Hello bass people,

I'm moving to a new apartment. I have two rooms to choose from to put my studio in, one big and one small. An isolation professional came to study the place. Since it's an apartment building, he suggested a floating room solution and the price he worked out for the small room was around 4.5k. I don't have a budget for that now.

I installed an SPL meter on my phone and when I'm playing the level goes up to 95db at times and usually under 90db. Do you think it'd be possible to use some form of insulation other than the floating room method to bring it down to acceptable levels for the neighbors? I know acoustic treatment and isolation are two different things, so I'm not looking at acoustic tiles here. I can consider building a second wall with some sort of noise reduction material and covering the ceiling that way too.

BTW, one of the rooms I can pick shares only the ceiling with a neighbor and the other has a shared wall plus a ceiling. Below my apartment is the parking lot.

Staple egg cartons to the walls (ghetto sound proofing). Go to your local grocery outlets, and rummage through the back dumpsters. Before you move out, you're going to have to patch the holes, and paint the room, but it works like a charm.

 

[EastCoastThump]

For sound reduction between spaces, egg cartons work like a charm from a gumball machine.

Egg cartons = sound treatment that will somewhat reduce the amount of high frequencies reflecting off walls back *into* room. (They lack the mass to do anything about low, or even low-mid, frequencies reflecting around the studio.)

And, more to the point, they'll do pretty much nothing to stop low frequencies traveling from the OP's studio to the neighboring apartments.

 

[silky smoove]

For sound reduction between spaces, egg cartons work like a charm from a gumball machine.

Egg cartons = sound treatment that will somewhat reduce the amount of high frequencies reflecting off walls back *into* room. (They lack the mass to do anything about low, or even low-mid, frequencies reflecting around the studio.)

And, more to the point, they'll do pretty much nothing to stop low frequencies traveling from the OP's studio to the neighboring apartments.

Additionally they surround your room in a flammable material. All sound treatments should be fire-rated, not fire-promoting. Just say no to egg cartons!

 

[EastCoastThump]

Here's a quick explanation of acoustic sound panels (absorbtion), bass traps, and diffusors

 

[FLORINS]

95 dB is quite loud for a residential space. I would find your way over to the Acoustics/Studio Building forum on Gearslutz. Do not bother covering your walls with egg crates, mattress pads (thin foam) or blankets - it will not help with isolating sound from your neighbors. Best of luck!

 

[seamonkey]

Here's a small study for "Isolation pads"
Testing Loudspeaker Isolation Products

Funny is that Auralex actually put out a video where they actually faked the results as they raised the cabinet but didn't try to adjust for the mic placement. It's total BS.

Money saved on snake oil can be better spent of better braced cabinets that don't excessively vibrate, or a high pass filter if you amp doesn't have one (most do now), or higher quality headphones.

 

[EastCoastThump]

Again, I don't think you quite see how the contexts for Winer's observations differ from those of the OP's question.

Ethan Winer discusses marketing claims that iso pads will clean up sonics at your studio's listening position when you're using nearfield studio monitors. His point about the smearing claim is on the money. In my experience, I've never heard any such smearing from nearfields causing the monitor bridge or desk to vibrate. (Tonal shifts from reflections off the desk, yes; but that's another different question.) Similarly, his claim about listening to studio monitors in the same room is also valid: direct acoustic energy will be stronger than reflections which will be stronger than vibrations—both b/c of the physics involved in reflected energy, but also b/c the line from nearfield monitors to the listening position is much shorter than the line the reflections travel.

But those observations don't address the conditions of the OP's question, which is about how to avoid disturbing his neighbors. Applying Winer's discussion to the OP's question has two problems.

The lesser—but still substantial—reason why this is apples and oranges is that most nearfields are designed for fidelity, and they minimize energy lost to cabinet vibration as part of that design strategy; bass cabinets generally don't. Add that to differences in their uses, and bass cabinets pushing high SPLs will convert more energy into mechanical vibration than a nearfield monitor run under typical conditions. (There's a reason your girlfriend isn't inclined to sit on your nearfield monitors.)

The other issue: Winer's point about the relative strength of direct sound is in the context of a listener in front of that nearfield monitor, which isn't the situation of the OP's neighbors in adjoining apartments or adjacent floors of his apartment building.

 

[EastCoastThump]

Money saved on snake oil can be better spent of better braced cabinets that don't excessively vibrate, or a high pass filter if you amp doesn't have one (most do now), or higher quality headphones.

But, as I said at the start, we agree that the OP would be wiser to avoid cranking his bass cab in the apartment.

And we also agree that if the OP were only interested in acoustic treatment of his studio as a listening space, an iso pad isn't going to do much

 

[sowilson]

Iso pads and then maybe lead sheets on the most likely walls and ceiling for transmission. Yes it's heavy, and yes it's a pain, but easier to do than a room in a room

 

[micguy]

I have a degree in Acoustical Physics. I live in a townhouse, where we have masonry walls between units. I practice via headphones. Isolating low end is really tough - the room within a room is what it takes. At $4.5 K, my bet is it won't be everything you hope for. We built a studio in our workplace a few years back. It isolates really well, even at low frequencies. A large part of the the isolation "recipe" in that facility is the concrete block (filled with cement) walls and pre-cast concrete ceiling. Mass is your friend, and you ain't gonna get that for cheap.