OF LISTENING ROOMS, SPEAKERS, AND SPONGY FLOORS
You know how a thing can start out simply and then go completely out of control?
You start out to fix a dripping faucet and end up with a backhoe digging up your front
yard?
My living room system has sat on a window seat facing into the room since I first
moved into this house. The equipment has varied but the location hasn’t. There’s
nothing to look at out of my living room window anyway and this space was adequate
for a CD player, amp and a couple of small speakers. It was fine for what it was,
mostly background music.
Since starting the web site, I have wanted to rearrange the living room to make it more
usable for critical listening and equipment comparisons. Doing this boiled down to
three easy steps.
1. Take the stereo equipment off the window seat.
2. Move the sofa from facing the window seat to backing to the window seat.
3. Set up the stereo equipment where the sofa used to be.
This was all I wanted to do.
Before I could set up the equipment, though, I needed some speaker stands. I spent
some time designing and building some prototype stands that I thought would work
well for the speakers I was using, the JBL L110s. The JBLs are large for bookshelf
speakers and heavy, almost 50 pounds each. I tried several designs and ended up
with some stands that were cheap to make and seemed to work well. I thought there
might be a good “build some easy speaker stands” article somewhere in all this but I
was wrong. As simple as the stands were, I still needed some clamps, a drill and bits,
glue, screws, a sander, and a laser-guided power miter box. Okay, I didn’t need the
miter box but it sure made it easier to cut the parts. All this took some time, but
eventually I got the stands done.
To keep the audio equipment itself off of the carpet, I recycled a little stand that I had
made for my prior home. It was designed to fit under a table and hold my Eico amp,
CD player, and tuner. This got painted the same color as the stands.
The paint I used was left over from my listening room, which was finished five years
ago. I had a lot of it. When I stirred the paint, though, I discovered that the bottom of
the can had rusted through. I could not figure out where the paint drips were all
coming from until I saw the pinholes in the bottom of the can. Once I got the drips
cleaned up, I got involved with sorting through all the old paint, a lot of which was
going bad. I saved what I could for touch-ups and let the cans dry out so they could
go in the trash. This took care of an afternoon.
The JBLs fit the stands really well and the integral adjusting screws/feet proved
invaluable for getting them level. Once I got them positioned and set up, though, I
noticed that the JBLs seemed to be bobbing up and down as I walked by them. I
thought at first it was just my imagination but simply shifting my weight in front of either
of them got them dancing. I knew the floor wasn’t really solid but had no idea that it
was this squishy. I can go down into the basement beneath the living room and
literally count the nails the professionals who built my house hammered into the floor
to anchor it. Perhaps, it would have helped if they had hit the floor joists.
A couple of days later, I gathered all the scrap ¾-inch thick wood and plywood I could
find in my garage and ripped it into strips about 1.5 inches wide. Grabbing a couple
of tubes of Liquid Nails that were getting old and my pneumatic nailer, I headed for the
basement.
I gooed up the strips on an edge and a side with the LN and pressed them against the
floor where it meets the joists and nailed them in place. I reinforced an area about 9
feet wide by 8 feet deep directly under and in front of the speakers. I let the LN set up
overnight. Click here for a boring photo.
Surprisingly, this bracing helped quite bit. The floor was noticeably less flexible
although it didn’t eliminate the problem entirely. The plywood flooring itself still
sagged in spots under the weight of the JBLs, but most of the bobbing was gone.
Finally, I was able to do some critical listening to the JBLs. They did not sound nearly
as good as I had hoped. The imaging was weak and shifted to the right. Worse the
bass just wasn’t there. Listening to Ray Brown or Charlie Haden, you wouldn’t know
they were playing a bass violin. The upper registers were there but not the lower, as
if only the neck of the instrument was being played. I measured the JBLs using the
Stereophile Test Disc 1 and the bass response fell like a rock under 80 Hz. Bummer.
The only other speakers I had around were some Mini Advents in the garage system.
I brought these in and put them on the stands. They imaged much better and the
bass playing sounded a lot more realistic. Frankly, they sounded a whole lot better.
Measuring them, they also dropped like a rock under 80 Hz but at least they have 5-
inch woofers as their excuse. The JBLs have 10s.
I have since discovered that the JBLs were refoamed incorrectly, which probably
accounts for much of the problem*. Their woofers are also in a cabinet of less than
1.5 cubic feet gross volume, which probably accounts for the rest. There may be
room effects, too; I haven’t been able to determine that yet.
As I mentioned in the March column, I have been looking for some speakers for the
living room. I found, on eBay, some refurbished Infinity Primus 360s for only $353 a
pair, shipped. I bought a pair and sent off a cashier’s check.
The 360s arrived about ten days later. I unpacked them and am impressed with what
you get for that little money. On the bottoms, however, the 360s have off-the-shelf
plastic feet. On a hard surface, they are adequately stable. On the living room
carpet, they tend to lean. I was concerned that I might be awakened one night by the
sound of them falling over. There is also no way to adjust them to get them level or
vertical. This had to be addressed.
I thought first of making some sort of plinth for each speaker but then decided an
outrigger setup would work better. I scoured my garage, Lowe’s, and the local
hardware store for something to make the outriggers from. I eventually settled on
some oak threshold about 1 ¾ inches wide, about ½ inch thick, and surprisingly stiff.
I had two packages of cones that I bought on sale at Parts Express. They are part
number 240-715 and come four to a package. Included with the cones are some
threaded adjusting studs, t-nuts, dimpled floor protectors, and little pads to hold the
protectors in place. I had gotten them for the JBL stands but hadn’t used them.
The 360s are only about 8 inches wide, so I made my outriggers 12 inches wide and
set a t-nut one inch in front each end. The t-nuts were epoxied in. The neat little
studs that came with the cones were now too short, so I bought some 50mm long
screws for adjusting the cones up and down.
To avoid any possibility of a future warranty issue, I used the holes left by the original
feet to attach the outriggers. I made a template first so I was sure I would hit the
original holes. Then I painted the tops of the outriggers black. (I didn’t want to risk
paint coming off on the carpet by painting the bottoms.) They match the finish on the
360s really well. I am pleased with how they look and have worked out.
Click here for photo 1.
Click here for photo 2.
Click here for photo 3.
Finally, I set up the 360s, knowing that the won’t fall over on their own, I can level
them, and that they will be doing substantially less bouncing up and down as I walk
around the room. Not bad for a month’s work.
True, I haven’t actually listened to the 360s yet, but will shortly. At least the speaker
cables are long enough, I think.
Tune in for Improving the Eico HF-81, Part 2, where I will discuss listening to the Eico
driving the Primus 360s in my rehabilitated living room.
Kent Johnson
March 15, 2006
*You might well ask, “Are you deaf? How come you didn’t notice this sooner?”
The JBLs got some decent bass reinforcement from the wall below them and the
windows behind them so the deficiency wasn’t quite as apparent. I knew it was a very
compromised setup and really didn’t listen too critically in order not to drive myself
crazy. It wasn’t until I did listen seriously, that I have had nothing but problems.
Ironically, the refoaming was done by an authorized JBL service center.
You know how a thing can start out simply and then go completely out of control?
You start out to fix a dripping faucet and end up with a backhoe digging up your front
yard?
My living room system has sat on a window seat facing into the room since I first
moved into this house. The equipment has varied but the location hasn’t. There’s
nothing to look at out of my living room window anyway and this space was adequate
for a CD player, amp and a couple of small speakers. It was fine for what it was,
mostly background music.
Since starting the web site, I have wanted to rearrange the living room to make it more
usable for critical listening and equipment comparisons. Doing this boiled down to
three easy steps.
1. Take the stereo equipment off the window seat.
2. Move the sofa from facing the window seat to backing to the window seat.
3. Set up the stereo equipment where the sofa used to be.
This was all I wanted to do.
Before I could set up the equipment, though, I needed some speaker stands. I spent
some time designing and building some prototype stands that I thought would work
well for the speakers I was using, the JBL L110s. The JBLs are large for bookshelf
speakers and heavy, almost 50 pounds each. I tried several designs and ended up
with some stands that were cheap to make and seemed to work well. I thought there
might be a good “build some easy speaker stands” article somewhere in all this but I
was wrong. As simple as the stands were, I still needed some clamps, a drill and bits,
glue, screws, a sander, and a laser-guided power miter box. Okay, I didn’t need the
miter box but it sure made it easier to cut the parts. All this took some time, but
eventually I got the stands done.
To keep the audio equipment itself off of the carpet, I recycled a little stand that I had
made for my prior home. It was designed to fit under a table and hold my Eico amp,
CD player, and tuner. This got painted the same color as the stands.
The paint I used was left over from my listening room, which was finished five years
ago. I had a lot of it. When I stirred the paint, though, I discovered that the bottom of
the can had rusted through. I could not figure out where the paint drips were all
coming from until I saw the pinholes in the bottom of the can. Once I got the drips
cleaned up, I got involved with sorting through all the old paint, a lot of which was
going bad. I saved what I could for touch-ups and let the cans dry out so they could
go in the trash. This took care of an afternoon.
The JBLs fit the stands really well and the integral adjusting screws/feet proved
invaluable for getting them level. Once I got them positioned and set up, though, I
noticed that the JBLs seemed to be bobbing up and down as I walked by them. I
thought at first it was just my imagination but simply shifting my weight in front of either
of them got them dancing. I knew the floor wasn’t really solid but had no idea that it
was this squishy. I can go down into the basement beneath the living room and
literally count the nails the professionals who built my house hammered into the floor
to anchor it. Perhaps, it would have helped if they had hit the floor joists.
A couple of days later, I gathered all the scrap ¾-inch thick wood and plywood I could
find in my garage and ripped it into strips about 1.5 inches wide. Grabbing a couple
of tubes of Liquid Nails that were getting old and my pneumatic nailer, I headed for the
basement.
I gooed up the strips on an edge and a side with the LN and pressed them against the
floor where it meets the joists and nailed them in place. I reinforced an area about 9
feet wide by 8 feet deep directly under and in front of the speakers. I let the LN set up
overnight. Click here for a boring photo.
Surprisingly, this bracing helped quite bit. The floor was noticeably less flexible
although it didn’t eliminate the problem entirely. The plywood flooring itself still
sagged in spots under the weight of the JBLs, but most of the bobbing was gone.
Finally, I was able to do some critical listening to the JBLs. They did not sound nearly
as good as I had hoped. The imaging was weak and shifted to the right. Worse the
bass just wasn’t there. Listening to Ray Brown or Charlie Haden, you wouldn’t know
they were playing a bass violin. The upper registers were there but not the lower, as
if only the neck of the instrument was being played. I measured the JBLs using the
Stereophile Test Disc 1 and the bass response fell like a rock under 80 Hz. Bummer.
The only other speakers I had around were some Mini Advents in the garage system.
I brought these in and put them on the stands. They imaged much better and the
bass playing sounded a lot more realistic. Frankly, they sounded a whole lot better.
Measuring them, they also dropped like a rock under 80 Hz but at least they have 5-
inch woofers as their excuse. The JBLs have 10s.
I have since discovered that the JBLs were refoamed incorrectly, which probably
accounts for much of the problem*. Their woofers are also in a cabinet of less than
1.5 cubic feet gross volume, which probably accounts for the rest. There may be
room effects, too; I haven’t been able to determine that yet.
As I mentioned in the March column, I have been looking for some speakers for the
living room. I found, on eBay, some refurbished Infinity Primus 360s for only $353 a
pair, shipped. I bought a pair and sent off a cashier’s check.
The 360s arrived about ten days later. I unpacked them and am impressed with what
you get for that little money. On the bottoms, however, the 360s have off-the-shelf
plastic feet. On a hard surface, they are adequately stable. On the living room
carpet, they tend to lean. I was concerned that I might be awakened one night by the
sound of them falling over. There is also no way to adjust them to get them level or
vertical. This had to be addressed.
I thought first of making some sort of plinth for each speaker but then decided an
outrigger setup would work better. I scoured my garage, Lowe’s, and the local
hardware store for something to make the outriggers from. I eventually settled on
some oak threshold about 1 ¾ inches wide, about ½ inch thick, and surprisingly stiff.
I had two packages of cones that I bought on sale at Parts Express. They are part
number 240-715 and come four to a package. Included with the cones are some
threaded adjusting studs, t-nuts, dimpled floor protectors, and little pads to hold the
protectors in place. I had gotten them for the JBL stands but hadn’t used them.
The 360s are only about 8 inches wide, so I made my outriggers 12 inches wide and
set a t-nut one inch in front each end. The t-nuts were epoxied in. The neat little
studs that came with the cones were now too short, so I bought some 50mm long
screws for adjusting the cones up and down.
To avoid any possibility of a future warranty issue, I used the holes left by the original
feet to attach the outriggers. I made a template first so I was sure I would hit the
original holes. Then I painted the tops of the outriggers black. (I didn’t want to risk
paint coming off on the carpet by painting the bottoms.) They match the finish on the
360s really well. I am pleased with how they look and have worked out.
Click here for photo 1.
Click here for photo 2.
Click here for photo 3.
Finally, I set up the 360s, knowing that the won’t fall over on their own, I can level
them, and that they will be doing substantially less bouncing up and down as I walk
around the room. Not bad for a month’s work.
True, I haven’t actually listened to the 360s yet, but will shortly. At least the speaker
cables are long enough, I think.
Tune in for Improving the Eico HF-81, Part 2, where I will discuss listening to the Eico
driving the Primus 360s in my rehabilitated living room.
Kent Johnson
March 15, 2006
*You might well ask, “Are you deaf? How come you didn’t notice this sooner?”
The JBLs got some decent bass reinforcement from the wall below them and the
windows behind them so the deficiency wasn’t quite as apparent. I knew it was a very
compromised setup and really didn’t listen too critically in order not to drive myself
crazy. It wasn’t until I did listen seriously, that I have had nothing but problems.
Ironically, the refoaming was done by an authorized JBL service center.
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