Down-firing subs and downstairs neighbors

Hello Audiogoners,

I am looking at subwoofers for 2 channel music. I will soon be moving into the 2nd floor of an older wooden house, with neighbors below me. I don’t want to drive my new neighbors crazy.

It seems intuitive that a downward-firing sub would penetrate the floor more than a forward-firing one--but is that true? Also, can you do things to mitigate, like put a down-firing sub on a piece of stone, or a particular material?

Any suggestions/info much appreciated
Your neighbors will want to kill you. I've been down that road. In fact, even with a slab of granite under a front-firing sub that I bought to replace the down-firing sub that nearly got me evicted, the sound traveled down the corner of the building right into their living room. Subs and apartments don't mix. What I ended up doing -- and what solved the problem -- was to switch to full-range speakers. If you want to go deeper than 35Hz or so, tough a house.
First question, how much insulation will be between your floor and your neighbor's ceiling (if it's none, which is probable the case, you asking for trouble, by putting in a subwoofer)? Second question, how loud to you like to listen to your music and at what time of day? Probably the biggest problem will the bass from your subwoofers bleeding into your neighbor's apartment, and it really doesn't matter whether the subwoofer is down-firing or forward-firing. And there is "no way" to stop this "sound bleed" unless you're willing to pull up your flooring and acoustically isolate and/or dampen the space between your floor and your neighbor's ceiling. If I was me living in such a situation, I would stick with stand-mounted monitors, and wait until I had a place where I could use a sub-woofer without bothering the neighbors. Other than that, once you get moved in, I would borrow a sub-woofer and test your system to see how much bass "sound bleed" goes into your downstair neighbor's apartment and what THEIR tolerance level might be. Remember if YOUR MUSIC is bleeding into their apartment, it's your responsibily to solve the problem.

PS: You signed the lease on the place, yet?
1. Subwoofer placement. (stay away from the corners. Try mid-front or mid-side wall). The goal is to get the smoothest respond without boominess and overloading the room.

2. Use of bass traps in all corners and sub_base like the one Auralex sells.

3. Seal all cracks, gaps etc. Use exp.foam to fill the outlet boxes, use caps to cover unused outlets. Get heavy carpet with extra thick padding.

4. Set you sub low to pickup only the lowest frequencies. Lower volume if nessesary.

Or, find another place that is more suitable for this hobby.

Full range speakers won't get you anywere. Low bass is not directional. Monitors might be a better choice for you. Use sub for referance listing sessions and turn it off for late hour listining.
Neighbors will kill you.
My advice is to hold off on the downward firing subwoofers.

Until you downstairs neighbors do something to piss you off.

Then buy two of them!

I live in an apartment, and always on the second floor.
I use a small B&W with it resting on a 24" square patio block, and that on thick rubber feet. It is a front firing with a port at the bottom. I find it can be used to assist in most non-Rock&Roll music. (For modern Rock, way too much bass is in the recording, and my neighbors are more important to me than loud thumping, so I TURN IT OFF.)
For Jazz, and classical it is a helper.
Major bass is IMPOSSIBLE in an apartment with someone under you, if you want to keep your lease.
The biggest bass problem is a syncronized strong beat mainly Rock&Roll, a syncopated beat is far more acceptable to others. A irregular beat, with large no-bass gaps can usually get by if the neighbors are not hypercritical, (such as in Jazz)
You can move to a first floor apt, in a corner.. and perhaps get away with a sub for all occasions.
Down-firing subs and downstairs neighbors = upfiring pistols
Thanks everyone for your suggestions! I'm glad I asked.

Does anyone know at about what frequency the bass becomes really bad (penetrating)? I'm thinking maybe I could find a shallow but musical sub to fill in between 40 and 80Hz, or one with two crossovers. Thanks

The frequency that the bass becomes really bad (penetrating) is dependent on a variety of factors, some of which are:

1. The room itself and how it effect bass frequencies.

2. How much insulation is between your floor and neighbor ceiling, and how well constructed the floor joist are.

3. The type of music you play, and how loud, and at what hours.

4. The types of dampening you plan to do (thick carpet/padding, ect) that you're going to use to prevent "sound bleed" into your neighbor's unit.

5. And probably the most important, the tolerance level of your "downstairs neighbors" towards any bass frequencies coming into their unit.

The fact that you're moving into an "older wooden house" pretty much tells me, you're going to having some issues with sound transmitting into your neighbors unit, as most older wooden homes are not well insulated and have many area in the walls and floors where sound will penetrate.

Once again, my suggestion would be stand mounted monitors that probably roll-off around 50 Hz, and to be mindful not to play your music at very high volume, as it doesn't take much for sound to start penetrating. As for the subwoofer, in your situation, I would forget about it, at least until you've moved into your apartment, and have had a chance to get to know your neighbors, and discuss what you want to do in regards to adding a subwoofer, and to get their reaction.
Hello Cleaneduphippy
I don't know anything about the innards of the new house (or the neighbors). Actually I have a sub already, a basic HT Velodyne I'm thinking of replacing. I'll see how it works in the new place before investing in a better one.

I use the sub now in a bi-amping arrangement with a NAD integrated (NAD only gets signal above 80hz). I like this arrangement--that's why I'm keen on having a sub. Don't care too much about very low bass.
Abarnett, I live in an upstairs duplex with two downfiring MJ subs. So far it has been good with no complaints. I did do the Auralex with bass traps, sound absobtion panels and diffusion (check out Guitar Center for the roominator kit). The livingroom is w/w carpets which helps insulate the floor. I am in the process of attatching a plinth with about an 1.5inch gap with the subs and some high quality spikes underneath (check Eden Sound for custom fits).

This is a must is get the Granite Audio Super Bass cd from Quuest for Sound. There are test tones from 10 to 99hz for 10 seconds which helps finding the noisy vibrations and rattles in the room and throughout the apartment. Use blu tak or rope caulk to calm everything down. Sometimes the bass might not be excessive but noisy vibrations can be harmful to the music but more disturbing to the neighbor downstairs.

Ofcourse being polite about the bass is just being a good neighbor. If company is downstairs, tone it down a bit. When the place is all yours, I am sure you can figure that out. As for me, I pretty much know the schedule downstairs and take it from there.

Good luck.
Great true "Audiogon" story about this very subject. A couple of years ago I was selling a Parasound C2 and I got an email from someone asking if I would ship to France. I had never done that before, but said I would look into it. After researching the process I found that shipping to any EU nation was a pain in the ___ but as luck would have it my wife and I were taking our first trip to Paris and could he pick it up there? Well turned out he lived in Paris but we didn't do the deal (customs at CDG would have been a nightmare with a piece of complicated electronics) but.... He was very appeciative of the effort and invited my wife and I to dinner while we were in Paris. I thanked him, but thought his offer was a simple courtesy.

To jump foward, when we arrived in Paris there was a bottle of Champagne and an offer of dinner. We of course accepted, had a great dinner and got to see Eric's system. They lived in an apartment, of course (which was amazing btw, on the Seine, not near it but on it, with a wall of windows looking out on the river framing the Eiffel Tower). He had commercial sub from a movie house, and I asked how his neighbors liked that. He had the only response that would work in that situation: The guy below him was completely deaf and could did not care. So if you look for a place with an old deaf guy below you, you can get any sub you like!!!
I own the building.

But truthfully, to keep good tenants I have to watch it. They've had loud parties late into the night and i'm cool with it, so if I have a loud moment its cool too. Plus they take trips often!

Also, an old wooden house is a musical instrument. Sound will permeate every crevice in the floors.

Best to have your own detached single family house.
Yeah, it doesn't really matter whether the sub is down-firing or not - as may have been mentioned here by others. You issue is that the subwoofers soundwaves are going to couple with the floor and walls and such, and translate out to your neighbors. Yes, some of the sound will actually pass through the materials and into the spaces as well.
Putting more insulation will help a tad bit for bass, but not enough, as bass waves are long - and you really need to put serious mass between you and any other zones, and/or "de-couple" the boundaries!
You could build almost a complete floating floor over your existing one, which will help quite a bit in keeping the bass down bellow significantly. However, the walls still attach the floor, which should have issolated walls to be more completely effective in your effort - and there are alternatives here, depending on how involved you want to, and CAN get.
If it were me, and I lived in an apartment, I would simply be satisfied with some larger bookshelves that played down to the high 40hz range, AND FORGET ABOUT IT!
Really, it's all about quality anyway. Small speakers do well in small spaces - set up well. If you had a large space that would support such a beast, then fine. You live with neighbors all around. So I would be happy simply considering them, and just enjoying what I have, personally. But, you might be coming from a different place.
I say this, as I really used to enjoy going over to a friends house and listening to music and movies on his really nice monitor system, 2 channel! (sans the sub).
Perhaps you could do some reasearch on sound issolation on the cheap? Hummmmmm....
How about this - you go on craigs list, and look for some office particians that someone is giving away for free, cause they're moving buildings or business's or something! Then, you use those as your floating floor base, as well as side walls!!!! That would work! Lol- you might have to firm up the pannels in places, like the floor. But hey!..they'd be free!...
It's a thought
good luck