TWEAKS
My initial idea for writing this article was simply to list all the tweaks I have
tried, rating each as to how effective I thought that particular tweak was. I
realized, however, that I really needed to define just what I meant by a tweak
itself. We all talk about tweaks but is a $149 duplex AC outlet really a
tweak? I have come up with the following criteria:
1. A tweak is an effort to improve the sound of a component without
being a component itself. Upgrading an amp with a different amp isn’t
tweaking.
2. A tweak is inexpensive relative to the cost of the component it is
designed to improve. For example, $50 cones under a $500 CD player are a
tweak; $1000 cones are not. The $1000 cones are a tweak under a $5,000
CD player, however. It makes no sense to spend more money tweaking a
component that you could spend replacing it with a superior sounding
component.
3. A tweak is reversible. This is what differentiates it from a
modification, which is so extensive that reversing it is not easy or in some
cases even possible. I would consider changing a cap in a crossover a tweak,
as it is cheap and reversible while changing the crossover to match a new
tweeter would be a modification. Clearly, this is a gray area and some of the
tweaks I am listing are certainly questionable, arbitrary, and capricious under
this criterion.
I considered adding a fourth criterion stating that a tweak should be
something that can be made/modified/or adapted to its purpose as this is
how most tweaks start out. Often, it isn’t until a tweak develops a fairly wide
acceptance that a manufactured version of the tweak appears. For example,
the first vibration control tweak I ever heard of was using golf shoe spikes to
support components. This was quickly followed by cones and supports
manufactured for that express purpose. While I think a lot of tweaking
starts out utilizing adapted materials, there are so many exceptions that,
ultimately, I decided that this wasn’t a very good or necessary criterion.
Here is the system I came up with the to rate the benefits of the tweaks I
have tried.
3 Tweak is a clearly audible improvement in audiophile terms, that is, it
may be quite subtle but a listener can discern it and would view it as an
improvement.
2 Tweak is not audible in and of itself but the theory/science seems
reasonable. There is the distinct possibility that such a tweak will have a
cumulative positive effect in cooperation with other similar tweaks.
1 Tweak is not audible and the basis for it is questionable in my mind. If
it does no harm to the sound, however, I am content to leave it in the
system in the hope that maybe it actually is doing something positive.
0 Tweak actually harms the sound of the system.
CABLES
The first tweaking I ever did was experimenting with speaker cables in the
early 1980s. I tried every available zip cord/wire that I found that seemed
like it would make a reasonable speaker cable. This was limited to some
extent by the connectors on the equipment at the time, which would not
accommodate particularly large wires. I heard no differences so I used the
largest gauge cable the receiver/speaker connectors would accept.
Zip cords as speaker cables—2
Interconnect cables—3
Speaker cables—3
Digital cables—3
Eichmann Bullet RCA Plugs—3 (See review)
Speaker cable elevators (homemade)—1 I’m sorry but I’m skeptical that the
electrical fields being generated along the speaker wires are interacting in
some audible way with the carpeting. Still making the elevators from pieces
of 2X4 was easy, cheap, and really helped to organize the cabling.
Unquestionably, the advent of high quality commercial audio cables
transformed what everyone was hearing through their systems. It is clear to
me that I never actually heard a lot of the components I owned, which, in
retrospect, is probably a good thing. The fact that a lot of older tube
equipment has become highly desirable and is getting restored is a good
indicator, to my mind, that we may not have heard the potential of a lot of
equipment at the time it was new.
If there are any “rules” for maximizing the benefits of good cables at this
time, they appear to be these:
· Interconnects as short as practical.
· Speaker cables at least eight feet long to reduce the modulating
effects of internal reflections.
· Digital cables at least one meter long, preferably longer, for the same
reason as the speaker cables.
COMPONENT SUPPORTS/VIBRATION CONTROL
Cones of various types—2
Vibrapods—2
Inner tubes—2
Granite blocks/wood blocks/tiles, etc.—2
Sand bags—3
Equipment rack—2/3
Tube damping rings—2
Sorbothane pucks and sheets—2
My experience with these tweaks is that, except for the sandbags, which I
have clearly heard damp some resonances, I have never clearly heard a
change of any kind as a result of using any of these items. I don’t know,
maybe I’ve just never had any real vibration problems but inserting most of
these items has made no audible difference that I can hear. This runs
against the conventional wisdom at the present in which reviewers routinely
hear noticeable improvements with the addition of these items. Some of
them, like Vibrapods, are so cheap that there is no reason not to use them.
I have had Vibrapods under my preamp, DAC, and transport and have heard
no difference with them in or out, however. I think the theory behind them
is sound but it hasn’t meant I have heard them make an improvement. The
same is true of the tube damping rings. I have them on the preamp tubes
and on the input tubes in the VTL amp. I heard no audible improvement but
if they are actually lessening microphonics, great. I’m all for that happening,
I just don’t hear it. I think the improvement wrought by my equipment rack
resulted more from organizing and shortening the interconnect cables than
from vibration control but I can’t say for sure.
AC EQUIPMENT
I have had the benefit of dedicated circuits in both my present and prior
listening rooms over the last twelve years. Presently, I have four dedicated
circuits available to my stereo setup: three 20 Amp and one 15 Amp. All four
are in use. One 20 Amp circuit powers the Hafler amp directly from the wall.
A second runs the VTL, which is on a G&W tube line conditioner presently
being evaluated and which will be reviewed shortly. The third powers all the
front-end equipment, except the DAC.
A Tripp Lite LC-1200 line conditioner/voltage regulator powers the Perpetual
Technology PA-1 and PA-3 wall warts from its own 15 Amp circuit. There is a
Monster HTS-1000 serving the preamp, crossover, and the Denon DCD 3300
running as a transport. I have also experimented with UPS units, a variety of
surge protectors, and outlet boxes. I have tried all of these units with
different components and in different setups and have yet to clearly hear any
difference, positive or negative, between using a given unit and just plugging
into the wall. At the same time, I just have to believe that these units are
making some sort of difference; I just wish I could hear it. I know the Tripp
Lite is working because I hear it clicking happily away when the refrigerator
comes on, the washer starts up, and at other times when I have no idea
what is causing it to react. For this reason it is actually located outside of my
listening room. Anyone who assumes that dedicated lines will totally stop or
limit the noise on AC lines will be disappointed. All dedicated lines do, in my
experience, are provide a more reliable level of power supply and assure you
that your amp isn’t on the same circuit with the air conditioning.
Despite my pretty much “neutral” experiences with AC tweaks I do have one
experience that I find interesting.
When I got my Hafler amp, the heaviest AC cord that I had with an IEC
female end was made of 16-gauge stranded wire. I shortened this cord to
about 3 feet and put on a Pass & Seymour male plug. I used the amp this
way for quite a while before I got around to trying any other cords.
Eventually, I purchased a three-foot length of 14-gauge wire at the local
home center and made up a new cord using the same male plug that was on
the 16-gauge cord and a new Marinco IEC end. I’m not sure why I did it, but
I decided to measure the bass output before switching cords using the
Stereophile Test Disc 1. The output of the bass is fairly uniform at my
listening position except for a dip at 50Hz that is some sort of room artifact.
The output level that I used was in the mid-70 dB range.
Switching the 14-gauge cord for the 16 boosted the output at every
frequency but 50 Hz by between 1 and 2.5 dB! Nothing was changed except
for the cord. Frankly, I was sort of flummoxed. In theory, the 16-gauge
cord is more than adequate electrically to power this amp to its full output
level, never mind the fairly benign level I was using.
I scooted back to the home center and got some 12-gauge wire and made
another cord using the same plug ends. Exchanging the 12-gauge wire for
the 14 provided an increase of between .5 and 1 dB at every level but 31.5
Hz, which was up less than .5 dB, and 25 Hz, which stayed the same.
If there had been no increase in output level going from the 14 to 12-gauge
wire, I would have attributed any increase to the Marinco connector,
assuming it was just making better contact at the amp input. Since the
output increased with the 12-gauge wire using the same components, the
increase has to be a result of the larger gauge wire. Exactly why this should
happen, I really don’t know. Bigger just appears to be better.
I was going to try 10-gauge wire but its overall diameter is just too big to fit
through the plug ends. I may get around to trying it using individual strands.
It was nice to get a worthwhile bass boost, nearly double the output power
actually, for so very little cost. I did end up adjusting the bass output level
down at the Dahlquist crossover when I settled on the 12-gauge cord.
Other than this experience, pretty much all of the rest of my AC tweaking
has yielded nothing audible, much less actually measurable. Here is the way I
have heard it:
Uninterruptible Power Supplies—2
Isolation Transformers—2
Commercial Line Filters (As noted herein)—2
AC Plugs, Outlets—2
AC Cables, commercial and home made—2
Ferrite Filters—2
Dedicated Lines—2
Pretty boring, huh?
Some notes: I have been reterminating my AC lines with Pass & Seymour
5266-X male AC plugs. These cost about $5 at a local lighting supply store.
This store also sells the hospital version of this plug for about $11. I haven’t
used the hospital version because it appears to be exactly the same unit as
the cheaper model, only with a clear plastic hospital housing. I readily
acknowledge that it may be different in some respect that is invisible to the
naked eye, but I sure couldn’t see any difference between the two units
disassembled. Unlike real reviewers I am not constantly plugging and
unplugging equipment, however, and I find the basic plug fits very tightly
into my wall outlets, which are also Pass & Seymour and cost just under $2
each.
I like the Marinco female 320IEC15 plug, mostly because it’s easy to work
with and readily available*. I have used the other less common IEC plug
(Schueter?), which is fine with small wire but becomes hard to work with as
the wire gauge gets larger. I think 14-gauge stranded wire is it’s practical
limit. *www.partsexpress.com
For more on my AC efforts check the review of the G&W TW-03D Line Noise
Filter for Tube Amplifiers.
ACOUSTICS
Boxes stuffed with newspaper in the corners of the room behind the
speakers—1
Home made “room lenses”—3
Listening Room—3
I have never had the money to invest in any of the serious commercial room
treatments so I have improvised. I made the “room lenses,” three of them,
for $65. If you subtract the cost of the hole saws I needed for drilling holes
in their bases, it was more like $40. Mine have bases made from a used MDF
bookshelf. I used nylon pan-head screws upside down in the bases for
leveling and I painted them an ivory color. They are stuffed with polyester
fiberfill, which splits one tube in each unit into halves, the second into thirds,
and the fourth into quarters. While I don’t think they function in any sense
as resonators (and why would you want them to randomly resonate?) I do
think they work very well as diffusers. I made my set so that my MG 10
speakers would each “see” the same environment even though one is about
4 feet from its sidewall and the other is about 11 feet from the other wall. I
have played with “lens” placement and I have concluded that they really do
seem to help the spaciousness of the imaging. I am presently using them as
follows: one centered between and behind the speakers and the other two
about two feet from each speaker and parallel to the axis between the
speakers. It looks weird but really seems to work. The downside is that the
people at Argent are not likely to put any ads on my web site.
When we moved from Denver to St. Louis (God help me!) I was utterly
unable to find any house with a decent finished basement or other area
suitable for a listening room at anything near our price range. Why it is so
expensive to live in a place with some of the dirtiest air in the country, awful
conditions for people with asthma and allergies, horrible traffic congestion,
virtually no mass transit, no environmental sensibility, no independent music
or book stores anywhere near where we live, the worst corporate polluters
ever seen on this earth, endemic racism, the most horrendous heat and
humidity known to man, and every variety of bug on the planet, I don’t know
but it is.
I settled, and I mean settled, for a house that has proven at least to have a
dry basement and that was feasible for constructing a listening room. I did
the planning, framing, electrical, insulating, and most of the painting myself.
I contracted out the perimeter drain system, HVAC work, drywall installation,
drywall finishing, and carpeting. We lived in this house for almost two and
one-half years before I got my stereo unpacked and running again. Was I
happy? To hear my stereo again, very. To have to wait that long? Better
we move on to other subjects.
I tried to make this room as acoustically excellent as my limited talents and
budget permitted and did a lot of research before starting. The room is
framed using steel framing, which obviates the need for resilient channel in
the walls and can’t be eaten by bugs--at least I don’t think so. Resilient
channel is used in the ceiling. The room is totally insulated both to keep
noise out and the sound in. The carpet is a thick Berber over a heavy pad. I
put in as many dedicated electrical lines as was possible. Bookshelves on the
wall opposite the stereo were part of the design as a way to dampen
standing bass waves and offset the effect of having a large patio door as the
remainder of the wall.
The room, which is approximately 24 by 30 feet with a 7.5-foot ceiling, (the
highest that could be managed) has worked out well. It is the best sounding
room I have ever had while still being usable as a recreation room. It is very
quiet. There is a room suck out at 50 Hz that I can’t seem to remove but
which also does not seem to negatively affect the sound in any way that I
can actually detect.
If you were to divide the room into four equal quadrants, the stereo area
occupies the entire northwest quadrant, some of the southwest, and
encroaches into the northeast and southeast. There are two support
columns in the room that make centering the system in the room impossible,
not that that would be a desirable setup anyway.
Because the room dimensions are so close to being multiples of each other,
which is not ideal, the axis of my system does not run parallel to the
sidewalls of the room. It is offset by a few degrees. Set up like this, there
are no walls parallel or perpendicular to the speakers. (Actually, there are no
walls perpendicular or parallel to each other thanks to the high quality
construction.) I think having the system axis non-parallel to the sidewalls is
an idea worth experimenting with even in smaller rooms.
I also designed an alcove for the equipment rack so that it is not in the room
but is “seen” as being part of the rear wall. There is a door at the back of
the alcove for access to the rear of the rack. This is the sort of setup that
would be impossible in most rooms. The equipment rack ends up behind (or
between) the speakers or out in the room somewhere. Behind the speakers,
the equipment is subject to more airborne vibrations; out in the room, there
are cable issues. (You can see how the rack is situated in the DIY rack
article.)
I consider myself extremely lucky to have the luxury of a room this large
dedicated for listening (and ping pong). I have to admit that I have read
articles by some reviewers describing their listening rooms and frankly have
wondered how they could possibly make any meaningful evaluation of sound
quality under those conditions. Yet many do.
OTHER MODS
Speaker Stands—3
Tubes—1 to 3
Parts Upgrades—1 to 3
Bi-wiring Speakers—3
External Crossovers—2
Contact Cleaners such as Cramolin, Pro Gold, etc—2
As usual, I have run off at the keyboard so I will make this mercifully short. I
did spend some time speaker building and there is no doubt in my mind that
bi-wiring is worthwhile. I also believe in external crossovers. Crossover
parts don’t need to be around huge amounts of vibration or constantly
fluctuating magnetic fields. It is also much easier to experiment when the
parts are not in the box. It was building speakers that gave me faith in my
own ears. I realized that I could hear just as well as many of the people
writing for the audio magazines and maybe better than some.
Tube and parts upgrades are not always going to result in audible
improvements so they get a fudged rating. I said some of my categories
were questionable and I meant it.
For now, keep on tweaking!
Kent Johnson
August 2005
My initial idea for writing this article was simply to list all the tweaks I have
tried, rating each as to how effective I thought that particular tweak was. I
realized, however, that I really needed to define just what I meant by a tweak
itself. We all talk about tweaks but is a $149 duplex AC outlet really a
tweak? I have come up with the following criteria:
1. A tweak is an effort to improve the sound of a component without
being a component itself. Upgrading an amp with a different amp isn’t
tweaking.
2. A tweak is inexpensive relative to the cost of the component it is
designed to improve. For example, $50 cones under a $500 CD player are a
tweak; $1000 cones are not. The $1000 cones are a tweak under a $5,000
CD player, however. It makes no sense to spend more money tweaking a
component that you could spend replacing it with a superior sounding
component.
3. A tweak is reversible. This is what differentiates it from a
modification, which is so extensive that reversing it is not easy or in some
cases even possible. I would consider changing a cap in a crossover a tweak,
as it is cheap and reversible while changing the crossover to match a new
tweeter would be a modification. Clearly, this is a gray area and some of the
tweaks I am listing are certainly questionable, arbitrary, and capricious under
this criterion.
I considered adding a fourth criterion stating that a tweak should be
something that can be made/modified/or adapted to its purpose as this is
how most tweaks start out. Often, it isn’t until a tweak develops a fairly wide
acceptance that a manufactured version of the tweak appears. For example,
the first vibration control tweak I ever heard of was using golf shoe spikes to
support components. This was quickly followed by cones and supports
manufactured for that express purpose. While I think a lot of tweaking
starts out utilizing adapted materials, there are so many exceptions that,
ultimately, I decided that this wasn’t a very good or necessary criterion.
Here is the system I came up with the to rate the benefits of the tweaks I
have tried.
3 Tweak is a clearly audible improvement in audiophile terms, that is, it
may be quite subtle but a listener can discern it and would view it as an
improvement.
2 Tweak is not audible in and of itself but the theory/science seems
reasonable. There is the distinct possibility that such a tweak will have a
cumulative positive effect in cooperation with other similar tweaks.
1 Tweak is not audible and the basis for it is questionable in my mind. If
it does no harm to the sound, however, I am content to leave it in the
system in the hope that maybe it actually is doing something positive.
0 Tweak actually harms the sound of the system.
CABLES
The first tweaking I ever did was experimenting with speaker cables in the
early 1980s. I tried every available zip cord/wire that I found that seemed
like it would make a reasonable speaker cable. This was limited to some
extent by the connectors on the equipment at the time, which would not
accommodate particularly large wires. I heard no differences so I used the
largest gauge cable the receiver/speaker connectors would accept.
Zip cords as speaker cables—2
Interconnect cables—3
Speaker cables—3
Digital cables—3
Eichmann Bullet RCA Plugs—3 (See review)
Speaker cable elevators (homemade)—1 I’m sorry but I’m skeptical that the
electrical fields being generated along the speaker wires are interacting in
some audible way with the carpeting. Still making the elevators from pieces
of 2X4 was easy, cheap, and really helped to organize the cabling.
Unquestionably, the advent of high quality commercial audio cables
transformed what everyone was hearing through their systems. It is clear to
me that I never actually heard a lot of the components I owned, which, in
retrospect, is probably a good thing. The fact that a lot of older tube
equipment has become highly desirable and is getting restored is a good
indicator, to my mind, that we may not have heard the potential of a lot of
equipment at the time it was new.
If there are any “rules” for maximizing the benefits of good cables at this
time, they appear to be these:
· Interconnects as short as practical.
· Speaker cables at least eight feet long to reduce the modulating
effects of internal reflections.
· Digital cables at least one meter long, preferably longer, for the same
reason as the speaker cables.
COMPONENT SUPPORTS/VIBRATION CONTROL
Cones of various types—2
Vibrapods—2
Inner tubes—2
Granite blocks/wood blocks/tiles, etc.—2
Sand bags—3
Equipment rack—2/3
Tube damping rings—2
Sorbothane pucks and sheets—2
My experience with these tweaks is that, except for the sandbags, which I
have clearly heard damp some resonances, I have never clearly heard a
change of any kind as a result of using any of these items. I don’t know,
maybe I’ve just never had any real vibration problems but inserting most of
these items has made no audible difference that I can hear. This runs
against the conventional wisdom at the present in which reviewers routinely
hear noticeable improvements with the addition of these items. Some of
them, like Vibrapods, are so cheap that there is no reason not to use them.
I have had Vibrapods under my preamp, DAC, and transport and have heard
no difference with them in or out, however. I think the theory behind them
is sound but it hasn’t meant I have heard them make an improvement. The
same is true of the tube damping rings. I have them on the preamp tubes
and on the input tubes in the VTL amp. I heard no audible improvement but
if they are actually lessening microphonics, great. I’m all for that happening,
I just don’t hear it. I think the improvement wrought by my equipment rack
resulted more from organizing and shortening the interconnect cables than
from vibration control but I can’t say for sure.
AC EQUIPMENT
I have had the benefit of dedicated circuits in both my present and prior
listening rooms over the last twelve years. Presently, I have four dedicated
circuits available to my stereo setup: three 20 Amp and one 15 Amp. All four
are in use. One 20 Amp circuit powers the Hafler amp directly from the wall.
A second runs the VTL, which is on a G&W tube line conditioner presently
being evaluated and which will be reviewed shortly. The third powers all the
front-end equipment, except the DAC.
A Tripp Lite LC-1200 line conditioner/voltage regulator powers the Perpetual
Technology PA-1 and PA-3 wall warts from its own 15 Amp circuit. There is a
Monster HTS-1000 serving the preamp, crossover, and the Denon DCD 3300
running as a transport. I have also experimented with UPS units, a variety of
surge protectors, and outlet boxes. I have tried all of these units with
different components and in different setups and have yet to clearly hear any
difference, positive or negative, between using a given unit and just plugging
into the wall. At the same time, I just have to believe that these units are
making some sort of difference; I just wish I could hear it. I know the Tripp
Lite is working because I hear it clicking happily away when the refrigerator
comes on, the washer starts up, and at other times when I have no idea
what is causing it to react. For this reason it is actually located outside of my
listening room. Anyone who assumes that dedicated lines will totally stop or
limit the noise on AC lines will be disappointed. All dedicated lines do, in my
experience, are provide a more reliable level of power supply and assure you
that your amp isn’t on the same circuit with the air conditioning.
Despite my pretty much “neutral” experiences with AC tweaks I do have one
experience that I find interesting.
When I got my Hafler amp, the heaviest AC cord that I had with an IEC
female end was made of 16-gauge stranded wire. I shortened this cord to
about 3 feet and put on a Pass & Seymour male plug. I used the amp this
way for quite a while before I got around to trying any other cords.
Eventually, I purchased a three-foot length of 14-gauge wire at the local
home center and made up a new cord using the same male plug that was on
the 16-gauge cord and a new Marinco IEC end. I’m not sure why I did it, but
I decided to measure the bass output before switching cords using the
Stereophile Test Disc 1. The output of the bass is fairly uniform at my
listening position except for a dip at 50Hz that is some sort of room artifact.
The output level that I used was in the mid-70 dB range.
Switching the 14-gauge cord for the 16 boosted the output at every
frequency but 50 Hz by between 1 and 2.5 dB! Nothing was changed except
for the cord. Frankly, I was sort of flummoxed. In theory, the 16-gauge
cord is more than adequate electrically to power this amp to its full output
level, never mind the fairly benign level I was using.
I scooted back to the home center and got some 12-gauge wire and made
another cord using the same plug ends. Exchanging the 12-gauge wire for
the 14 provided an increase of between .5 and 1 dB at every level but 31.5
Hz, which was up less than .5 dB, and 25 Hz, which stayed the same.
If there had been no increase in output level going from the 14 to 12-gauge
wire, I would have attributed any increase to the Marinco connector,
assuming it was just making better contact at the amp input. Since the
output increased with the 12-gauge wire using the same components, the
increase has to be a result of the larger gauge wire. Exactly why this should
happen, I really don’t know. Bigger just appears to be better.
I was going to try 10-gauge wire but its overall diameter is just too big to fit
through the plug ends. I may get around to trying it using individual strands.
It was nice to get a worthwhile bass boost, nearly double the output power
actually, for so very little cost. I did end up adjusting the bass output level
down at the Dahlquist crossover when I settled on the 12-gauge cord.
Other than this experience, pretty much all of the rest of my AC tweaking
has yielded nothing audible, much less actually measurable. Here is the way I
have heard it:
Uninterruptible Power Supplies—2
Isolation Transformers—2
Commercial Line Filters (As noted herein)—2
AC Plugs, Outlets—2
AC Cables, commercial and home made—2
Ferrite Filters—2
Dedicated Lines—2
Pretty boring, huh?
Some notes: I have been reterminating my AC lines with Pass & Seymour
5266-X male AC plugs. These cost about $5 at a local lighting supply store.
This store also sells the hospital version of this plug for about $11. I haven’t
used the hospital version because it appears to be exactly the same unit as
the cheaper model, only with a clear plastic hospital housing. I readily
acknowledge that it may be different in some respect that is invisible to the
naked eye, but I sure couldn’t see any difference between the two units
disassembled. Unlike real reviewers I am not constantly plugging and
unplugging equipment, however, and I find the basic plug fits very tightly
into my wall outlets, which are also Pass & Seymour and cost just under $2
each.
I like the Marinco female 320IEC15 plug, mostly because it’s easy to work
with and readily available*. I have used the other less common IEC plug
(Schueter?), which is fine with small wire but becomes hard to work with as
the wire gauge gets larger. I think 14-gauge stranded wire is it’s practical
limit. *www.partsexpress.com
For more on my AC efforts check the review of the G&W TW-03D Line Noise
Filter for Tube Amplifiers.
ACOUSTICS
Boxes stuffed with newspaper in the corners of the room behind the
speakers—1
Home made “room lenses”—3
Listening Room—3
I have never had the money to invest in any of the serious commercial room
treatments so I have improvised. I made the “room lenses,” three of them,
for $65. If you subtract the cost of the hole saws I needed for drilling holes
in their bases, it was more like $40. Mine have bases made from a used MDF
bookshelf. I used nylon pan-head screws upside down in the bases for
leveling and I painted them an ivory color. They are stuffed with polyester
fiberfill, which splits one tube in each unit into halves, the second into thirds,
and the fourth into quarters. While I don’t think they function in any sense
as resonators (and why would you want them to randomly resonate?) I do
think they work very well as diffusers. I made my set so that my MG 10
speakers would each “see” the same environment even though one is about
4 feet from its sidewall and the other is about 11 feet from the other wall. I
have played with “lens” placement and I have concluded that they really do
seem to help the spaciousness of the imaging. I am presently using them as
follows: one centered between and behind the speakers and the other two
about two feet from each speaker and parallel to the axis between the
speakers. It looks weird but really seems to work. The downside is that the
people at Argent are not likely to put any ads on my web site.
When we moved from Denver to St. Louis (God help me!) I was utterly
unable to find any house with a decent finished basement or other area
suitable for a listening room at anything near our price range. Why it is so
expensive to live in a place with some of the dirtiest air in the country, awful
conditions for people with asthma and allergies, horrible traffic congestion,
virtually no mass transit, no environmental sensibility, no independent music
or book stores anywhere near where we live, the worst corporate polluters
ever seen on this earth, endemic racism, the most horrendous heat and
humidity known to man, and every variety of bug on the planet, I don’t know
but it is.
I settled, and I mean settled, for a house that has proven at least to have a
dry basement and that was feasible for constructing a listening room. I did
the planning, framing, electrical, insulating, and most of the painting myself.
I contracted out the perimeter drain system, HVAC work, drywall installation,
drywall finishing, and carpeting. We lived in this house for almost two and
one-half years before I got my stereo unpacked and running again. Was I
happy? To hear my stereo again, very. To have to wait that long? Better
we move on to other subjects.
I tried to make this room as acoustically excellent as my limited talents and
budget permitted and did a lot of research before starting. The room is
framed using steel framing, which obviates the need for resilient channel in
the walls and can’t be eaten by bugs--at least I don’t think so. Resilient
channel is used in the ceiling. The room is totally insulated both to keep
noise out and the sound in. The carpet is a thick Berber over a heavy pad. I
put in as many dedicated electrical lines as was possible. Bookshelves on the
wall opposite the stereo were part of the design as a way to dampen
standing bass waves and offset the effect of having a large patio door as the
remainder of the wall.
The room, which is approximately 24 by 30 feet with a 7.5-foot ceiling, (the
highest that could be managed) has worked out well. It is the best sounding
room I have ever had while still being usable as a recreation room. It is very
quiet. There is a room suck out at 50 Hz that I can’t seem to remove but
which also does not seem to negatively affect the sound in any way that I
can actually detect.
If you were to divide the room into four equal quadrants, the stereo area
occupies the entire northwest quadrant, some of the southwest, and
encroaches into the northeast and southeast. There are two support
columns in the room that make centering the system in the room impossible,
not that that would be a desirable setup anyway.
Because the room dimensions are so close to being multiples of each other,
which is not ideal, the axis of my system does not run parallel to the
sidewalls of the room. It is offset by a few degrees. Set up like this, there
are no walls parallel or perpendicular to the speakers. (Actually, there are no
walls perpendicular or parallel to each other thanks to the high quality
construction.) I think having the system axis non-parallel to the sidewalls is
an idea worth experimenting with even in smaller rooms.
I also designed an alcove for the equipment rack so that it is not in the room
but is “seen” as being part of the rear wall. There is a door at the back of
the alcove for access to the rear of the rack. This is the sort of setup that
would be impossible in most rooms. The equipment rack ends up behind (or
between) the speakers or out in the room somewhere. Behind the speakers,
the equipment is subject to more airborne vibrations; out in the room, there
are cable issues. (You can see how the rack is situated in the DIY rack
article.)
I consider myself extremely lucky to have the luxury of a room this large
dedicated for listening (and ping pong). I have to admit that I have read
articles by some reviewers describing their listening rooms and frankly have
wondered how they could possibly make any meaningful evaluation of sound
quality under those conditions. Yet many do.
OTHER MODS
Speaker Stands—3
Tubes—1 to 3
Parts Upgrades—1 to 3
Bi-wiring Speakers—3
External Crossovers—2
Contact Cleaners such as Cramolin, Pro Gold, etc—2
As usual, I have run off at the keyboard so I will make this mercifully short. I
did spend some time speaker building and there is no doubt in my mind that
bi-wiring is worthwhile. I also believe in external crossovers. Crossover
parts don’t need to be around huge amounts of vibration or constantly
fluctuating magnetic fields. It is also much easier to experiment when the
parts are not in the box. It was building speakers that gave me faith in my
own ears. I realized that I could hear just as well as many of the people
writing for the audio magazines and maybe better than some.
Tube and parts upgrades are not always going to result in audible
improvements so they get a fudged rating. I said some of my categories
were questionable and I meant it.
For now, keep on tweaking!
Kent Johnson
August 2005
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