Happy thoughts

[Gandhi]

I decided to start a thread about psychoacoustics. (Perhaps not the most
obvious choice for thinking happy thoughts. And in the audiophile
section as well...)

Does anyone have any thought-provoking psychoacoustic phenomena to
share?

I'll go first. Perhaps you already know of them, but they were unknown
to me.

Shepard tone - How the Batpod appears to be forever accelerating
https://en.wikipedia.org/wiki/Shepard_tone

Hearing melodies in a constant spectrum
https://en.wikipedia.org/wiki/Constant_spectrum_melody

Seeing is hearing
https://en.wikipedia.org/wiki/McGurk_effect



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
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[andy_c]

One good source of information about psychoacoustics and how it relates
to sound reproduction can be found in '_Floyd_Toole's_book_'
(http://www.amazon.com/Sound-Reproduction-Acoustics-Psychoacoustics-Loudspeakers/dp/0240520092/ref=sr_1_1?s=books&ie=UTF8&qid=1402868463&sr=1-1&keywords=floyd+toole)
(Amazon link). There's a '_free_PDF_'
(http://audioroundtable.com/misc/Loudspeakers_and_Rooms.pdf) available
of an article he wrote on the subject that's a precursor to his book.
So if you like the article, you'll probably like the book too. Here is

2 AUDIBLE EFFECTS OF REFLECTIONS—
A SURVEY
In anticipation of experimental results showing listener
reactions to reflections in a variety of circumstances, it is
useful to have some perspective on what might be found.
• Localization (direction)—the precedence effect
• Localization (distance)
• Image size and position
• Sense of space
• Timbre: comb filtering, repetition pitch
• Timbre: audibility of resonances
• Speech intelligibility

Toole is retired from Harman and spent his life's work on the subject.


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[Gandhi]

Thanks! I downloaded it and hopefully I have read it by tomorrow.



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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[netchord]

Transporter + Balvenie DoubleWood = Happy Thoughts.



--
4 TB Drobo-->FW 800-->mac mini-->Ethernet
Transporter--> Wireworld Eclipse 6 coax-->Meridian G61
G61--> Nordost Red Dawn-->Primare 30.3
Primare-->Ocos--Vienna Acoustics Beethoven/Maestro
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[Gandhi]

Post by netchord
Transporter + Balvenie DoubleWood = Happy Thoughts.

With the right dose, the Transporter isn't even needed.



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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[Gandhi]

Post by andy_c
One good source of information about psychoacoustics and how it relates
to sound reproduction can be found...

Ooo, this was very interesting!

According to this paper, reflections are neutral or benign in small
rooms (except in the LF range). Who knew?

Adaptation seems to be powerful. Roughly speaking; before adaptation the
room is the significant factor and the loudspeaker isn't, and vice
versa. Perhaps this is the most important factor in the infamous
breaking-in of speakers? (Not cables or such, that falls into the
category of in dire need of heavy medication.) And yes, I know that one
common explanation is the subtle untightening of screws due to
vibrations, which doesn't seem unlikely.

It really puts some of "common audiophile knowledge" in perspective.
Both pure myths but also expert advice from, for instance, loadspeaker
manufacturers. Physical models of wave propagation don't seem to be
enough, we simply don't hear precisely what is measured. The physical
models so far only concern what reaches the ear drums (or possibly the
end of the cochlear nerve), we are not yet able to measure the impact of
the extensive processing happening in our minds during the act of
hearing. Granted, this is not a new concept at all, but at least I
haven't previously had a glimpse of the magnitude of importance.

I have so far only read half of the paper and I'm sure more revelations
are to come.



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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[Gandhi]

Ooo, this was very interesting!<Religious awakening>

Perhaps a better way of improving the listening experience than buying
new speakers is by professional listening therapy by a KBT shrink on a
weekly basis?



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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[andy_c]

My understanding from reading the paper and Toole's book is that
reflections from the front and back walls may not be beneficial for
giving the illusion of spaciousness because the reflected components of
the sounds in the left and right ears caused by them are highly
correlated, while the opposite is true for side wall reflections.

My home that I moved into a few years ago is one of those "open-plan"
homes that seem to be popular nowadays. Also, it has hard tile floors
on all but the bedrooms and study. So kitchen, dining room, living room
and hallway running all the way from front door to back are all hard
tile. Floors and ceiling are drywall. When I first moved in, it
sounded like a cave, with all sorts of late echoes. In the listening
area, I put a large area rug, big squishy leather couches and chair
forming a U shape, and hanging decorative rugs on front and back walls
(but not the side). This seems to have completely tamed the cave effect
in the living room where my system is, but it is still prevalent in the
kitchen and dining room, which are dominated by hard surfaces.

Next project is multiple subwoofers! That's an interesting aspect of
the paper too.


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[Gandhi]

Post by andy_c
My understanding from reading the paper and Toole's book is that
reflections from the front and back walls may not be beneficial for
giving the illusion of spaciousness because the reflected components of
the sounds in the left and right ears caused by them are highly
correlated, while the opposite is true for side wall reflections.
My home that I moved into a few years ago is one of those "open-plan"
homes that seem to be popular nowadays. Also, it has hard tile floors
on all but the bedrooms and study. So kitchen, dining room, living room
and hallway running all the way from front door to back are all hard
tile. Floors and ceiling are drywall. When I first moved in, it
sounded like a cave, with all sorts of late echoes. In the listening
area, I put a large area rug, big squishy leather couches and chair
forming a U shape, and hanging decorative rugs on front and back walls
(but not the side). This seems to have completely tamed the cave effect
in the living room where my system is, but it is still prevalent in the
kitchen and dining room, which are dominated by hard surfaces.
Next project is multiple subwoofers! That's an interesting aspect of
the paper too.

Ah. I have it all backwards. The room size and the way it's furnished
doesn't really allow for much squishy stuff on the front och back walls,
so I have not done anything there. But I've always taken comfort in the
fact that at least I have book shelves on the side walls of the room.
Perhaps any amount of soft matter at the front or back would be an
improvement? Sometimes I see people having a kind of room treatment, a
sort of board roughly the size of a newspaper, standing on the floor by
the front wall, directly behind the speakers. Do they help much?

I use Digital Room Correction and it makes a substantial improvement.
But it's very obvious that you can't cheat the laws of physics.

Since we're discussing psychoacoustics, perhaps this new knowledge alone
will make me less satisfied with the sound of my current setup.

I'd like to, but dare not use subwoofers. I have a neighbor with such a
contraption and this buildning clearly wasn't constructed with that in
mind. I don't want to stress my neighbors more that I already do. And I
do. But just for adding to my brainweight, or in case I move house soon
(I'm looking), please let me know any good ideas.



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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[get.amped]

Post by Gandhi
I'd like to, but dare not use subwoofers. I have a neighbor with such a
contraption and this buildning clearly wasn't constructed with that in
mind. I don't want to stress my neighbors more that I already do. And I
do. But just for adding to my brainweight, or in case I move house soon
(I'm looking), please let me know any good ideas.

Surprisingly, not all sub-woofers are created equal :rolleyes:

I have found that the ones intended for home theater low frequency
effects are rarely appropriate for music reproduction. They rumble and
shake most impressively, but don't have the same tight, punchy bass that
I get from my Quads.

There are subs specifically designed for music that provide nice
reinforcement in the 30-60Hz range that many monitor/bookshelf sized
speakers struggle to reproduce well.



Win7Pro(x64)[3.3Ghz i5, 8GB RAM, 120GB SSD system, 15TB storage], LMS
7.9.0 -> Logitech Squeezebox Classic V.3 -> Cambridge Audio DacMagic ->
NAD C160 -> 2 x NAD C272 -> Quad 22L2
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[Gandhi]

Post by get.amped
I have found that the ones intended for home theater low frequency
effects are rarely appropriate for music reproduction. They rumble and
shake most impressively, but don't have the same tight, punchy bass that
I get from my Quads.
There are subs specifically designed for music that provide nice
reinforcement in the 30-60Hz range that many monitor/bookshelf sized
speakers struggle to reproduce well.

Yes, I know there are different kinds, but I have never really given it
any thought in this case. I just implicitly assumed it was my annoying
neighbor's choice of music, or whatever one should call that roaring
stuff. But actually, when I think about it, he seems to use his sub
mostly for gaming, so it's probably safe to assume that it's one of the
cheaper and shakier varieties. And explosions are seldom particularly
musical.

I have decent floorstanders, which go down to 30 Hz, but they could be
more controlled at the bottom end. That probably mostly depends on room
modes, speaker placement and so on. But still. It would be interesting
to try out a high class sub, or perhaps even multiple ones, tuned to
perfection for precisely my livingroom. Hmm. Something to consider for
my future (bigger and hopefully more soundproof) apartment.



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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[get.amped]

My Quads claim to go down to 30Hz +/- 6dB but I have no way of knowing
whether they do. I have a Quad sub as part of the L-ite system for HT
that is supposed to go down to 25Hz and that system sounds really good
for multi-channel programs including live concert DVD/Blu-ray discs. But
for 2 channel stereo music, the floorstanders are far superior,
particularly sitting in the sweet spot in the Lazyboy.

And then I've got the vintage Boston Acoustic Lynnfield VR system
(VR-M60 mains, VR-MX surrounds, VR-920 center and PV-1000 sub) in the
living room for TV and movies. BA really hit their stride with this
series and these pieces have held up well over the years.



Win7Pro(x64)[3.3Ghz i5, 8GB RAM, 120GB SSD system, 15TB storage], LMS
7.9.0 -> Logitech Squeezebox Classic V.3 -> Cambridge Audio DacMagic ->
NAD C160 -> 2 x NAD C272 -> Quad 22L2
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[andy_c]

Post by Gandhi
I'd like to, but dare not use subwoofers. I have a neighbor with such a
contraption and this buildning clearly wasn't constructed with that in
mind. I don't want to stress my neighbors more that I already do. And I
do. But just for adding to my brainweight, or in case I move house soon
(I'm looking), please let me know any good ideas.

The multiple subwoofer idea is a deep rabbit hole. :D One of its
proponents is Earl Geddes, a guy who did his Ph.D dissertation three
decades ago on acoustics of small rooms. A good place to start might be
'_this_blog_post_'
(http://seriousaudioblog.blogspot.com/2012/05/two-great-articles-on-multiple.html),
which hosts two PDF files concerning multiple sub theory and setup
procedure written by Dr. Geddes, along with some commentary by the
blogger, who goes by the nym of DS-21 on several forums.

There's also a '_video_by_Earl_on_this_topic_'
(http://www.ustream.tv/recorded/28637776/highlight/323843) which has an
associated '_PowerPoint_presentation_'
(http://gedlee.azurewebsites.net/Papers/OptimalBassPlaybackinSmallRooms.pptx)
(PPTX file), which helps, as the display of the PowerPoint slides in the
video is hard to read. Also, this video skips the beginning of the
presentation which was disturbed by a number of technical problems with
the video equipment. Reading the beginning of the PPTX file helps to
fill in the missing details from the beginning.

I see you're using Linux. I'm on Windows, and LibreOffice is working
well for viewing the PPTX file.

These techniques rely on measurement capability. I'm using the free
Room EQ Wizard, along with an inexpensive measurement mic and an
external USB sound adapter that has a mic preamp with phantom power for
the mic built in. I see from your sig that you're using some room
correction software, so I guess you already have measurement capability.


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[Mnyb]

Very interesting , my aproach for what iit's worth , it probably has
some flaws.

Damping the room enough to,get rid of flutter echo ( the garage / cave
sound ) using some odd bits of acoustic material , mostly behind me I'm
sitting close to the back wall .

Use digital room correction for the bass , built in DRC in my
pre-processor .

Speaker placement L,R placed at 1/3 and 2/3 of the lengt of a long wall
in my rectangular room 1/5 of the depth out in the room.
Some fine tuning by ear mostly the angle inwards the listening position
.

Centre is in the middle but at ear high when I'm sitting in the sofa
,65" plasma above centre speaker .
Many have the centre very close to the floor this sucks midrange gets
really coloured .
I listen a lot in Meridian trifield mode actually using all 5ch for
stereo music .

Subwoofer at 1/5 of depth and length not in corner , probably a waste of
capability but excites less modes .
Low xover frequ to sub 50-60hz using the pre amp processors fillter .

Note sub is also filtered by the DRC ! This i think is essential for
good one sub integration the DRC makes it really gel together .
But xover must be at low frequency and main speakers must be able to
reproduce some bass . Xover filter must be steep

I don't think you can integrate to small main speakers with a single sub
xover would be to high and you need 2 subs close to the speakers , in
many cases I've heard the xover is a bit on the high side and sub still
has audible contribution at 2*fs and as the sub is not perfect it also
does other things like port sounds .

It still not perfect but very good but even better bass I need bigger
main speakers and 2 or more large closed box subwoofers :)

I imagine there is a lot of improvement to do to my aproach :)

Where is 1/3 coming from ?
I noticed that many speaker placement softwares simply suggest a grid of
positions at odd multiples of room dimensions they often has 1/3 near
the top of the list .
There is quite a lot of them so it may be hard to try them all manually
.
But a room has many other constraints it's a living room with furniture
and doors opening and windows , this often means that the side of the
room where the speakers will be is " given " and possibly also where the
sub will be .



--------------------------------------------------------------------
Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x
MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3
sub.
Bedroom/Office: Boom
Kitchen: Touch + powered Fostex PM0.4
Misc use: Radio (with battery)
iPad1 with iPengHD & SqueezePad
(in storage SB3, reciever ,controller )
server HP proliant micro server N36L with ClearOS Linux

http://people.xiph.org/~xiphmont/demo/neil-young.html
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[Gandhi]

Post by Mnyb
Damping the room enough to,get rid of flutter echo ( the garage / cave
sound ) using some odd bits of acoustic material , mostly behind me I'm
sitting close to the back wall .

What kind of acoustic material are you using behind you on the back
wall? How thick? Is it the entire wall, or mostly around the sofa, a bit
over ear height? Or...?

PS
If my house were burned to the ground, I'd start over again with all
Meridian gear. It's a very good concept and the quality seems just as
good.



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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View this thread: http://forums.slimdevices.com/showthread.php?t=101723

[Mnyb]

Post by Gandhi
What kind of acoustic material are you using behind you on the back
wall? How thick? Is it the entire wall, or mostly around the sofa, a bit
over ear height? Or...?
PS
If my house were burned to the ground, I'd start over again with all
Meridian gear. It's a very good concept and the quality seems just as
good.

Some 1 inch thisc material covering the whole area behind the sofa
extending to my rear channels and it ends a foot before the ceiling .

Some of it behind the open frame hif rack and speakers + thick rugs on
the floor . bookshelfs stuffed with books or CD's or dvd's (no boxy
cabinets or glass cabinets with trinkets or door on the bookshelfs)



--------------------------------------------------------------------
Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x
MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3
sub.
Bedroom/Office: Boom
Kitchen: Touch + powered Fostex PM0.4
Misc use: Radio (with battery)
iPad1 with iPengHD & SqueezePad
(in storage SB3, reciever ,controller )
server HP proliant micro server N36L with ClearOS Linux

http://people.xiph.org/~xiphmont/demo/neil-young.html
------------------------------------------------------------------------
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[Gandhi]

Post by andy_c
The multiple subwoofer idea is a deep rabbit hole. :D One of its
proponents is Earl Geddes, a guy who did his Ph.D dissertation three
decades ago on acoustics of small rooms. A good place to start might be
'_this_blog_post_'
(http://seriousaudioblog.blogspot.com/2012/05/two-great-articles-on-multiple.html),
which hosts two PDF files concerning multiple sub theory and setup
procedure written by Dr. Geddes, along with some commentary by the
blogger, who goes by the nym of DS-21 on several forums.
There's also a '_video_by_Earl_on_this_topic_'
(http://www.ustream.tv/recorded/28637776/highlight/323843) which has an
associated '_PowerPoint_presentation_'
(http://gedlee.azurewebsites.net/Papers/OptimalBassPlaybackinSmallRooms.pptx)
(PPTX file), which helps, as the display of the PowerPoint slides in the
video is hard to read. Also, this video skips the beginning of the
presentation which was disturbed by a number of technical problems with
the video equipment. Reading the beginning of the PPTX file helps to
fill in the missing details from the beginning.
I see you're using Linux. I'm on Windows, and LibreOffice is working
well for viewing the PPTX file.
These techniques rely on measurement capability. I'm using the free
Room EQ Wizard, along with an inexpensive measurement mic and an
external USB sound adapter that has a mic preamp with phantom power for
the mic built in. I see from your sig that you're using some room
correction software, so I guess you already have measurement capability.

Interesting. I have read the PDF files and must say that most of his
points och conclusions are quite surprising to me. It's not how I have
interpreted other sources. I'm not questioning him, he seems to have
done his homework, I'm just surprised. His views are also very strong.
Do these views represent common knowledge?

I'm using REWv5 too. Very comprehensive and capable software. I have a
calibrated Behringer ECM8000 mic and a M-Audio Fast Track Pro mic
preamp. So I have the measuring capability, but apart from not wanting
to trouble my neighbors even more, I'm a bit challenged in the floor
space department.



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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[andy_c]

Post by Gandhi
Interesting. I have read the PDF files and must say that most of his
points och conclusions are quite surprising to me. It's not how I have
interpreted other sources. I'm not questioning him, he seems to have
done his homework, I'm just surprised. His views are also very strong.

It's hard to answer your concern without more specific information (what
specific sources are you referring to, what contradictions you are
encountering, and so on). Regarding his strong views, I know what you
mean. It seems to be a quirk of his style that when asked a question,
he will answer unequivocally. I've found that if asked a follow-up
question to test just how strongly he holds these views, he will often
equivocate.

Post by Gandhi
Do these views represent common knowledge?

These are somewhat new developments. There are other workers in the
field who have reached similar conclusions, with products based on them.
Harman seems to be active in this area. Todd Welti and Allan Devantier
of Harman wrote an article a while back called
"'_Low-Frequency_Optimization_Using_Multiple_Subwoofers_'
(mkloudspeakers.com/pdf/todd-welti-white-paper.pdf)", which is worth a
read.

The basic idea is this. Let's say you already have a multi-sub system,
and you measure the bass response at multiple listening positions. If
you use EQ that's common to all subs, it causes the same change in
frequency response at all listening positions. So it cannot improve the
variation in frequency response with position. If individual gain,
delay and EQ are provided for each sub, then it's possible to control
how the subs interact with one another as a function of listening
position to reduce the variation of frequency response with position.
Welti and Devantier describe a technique they call Sound Field
Management (SFM) which is now used in the JBL Arcos product, a
super-expensive system not really accessible to most people. Here's how
part of it works. They define a statistical measure called Mean Spatial
Variance (MSV), which is a measure of how much the frequency response
varies with position in the bass region. The software uses an algorithm
that adjusts on a per-subwoofer basis the gain, delay, and the
parameters of one PEQ per sub to find the configuration that minimizes
the MSV, independent of what the resulting frequency response is. Then
they use global EQ to clean up the non-flat response. This is all
described in their paper.

An earlier attempt by Harman to accomplish a similar goal was in a
product called BassQ. It did not use SFM, but rather the so-called
matrix inversion technique also described in the paper linked above.
Here's a '_review_of_the_BassQ_'
(http://www.avsforum.com/forum/90-receivers-amps-processors/1163240-jbl-bassq.html#post16916242)
by Roger Dressler of Dolby Labs.

Geddes uses a different approach. One reason is that Harman's approach
is patented, so he's trying to avoid getting caught up in that. Also,
Geddes is concentrating on getting equivalent results with commonly
available low-cost EQ hardware, such as the Behringer DCX2496 and
miniDSP.

Not sure if I answered your question, but my goal was to provide more
technical justification (which seemed to be at the heart of your
question). These issues seem to be explored more in the AV realm than
the two-channel audio world.


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[Gandhi]

These are somewhat new developments... The basic idea is this...

Seem reasonable. Perhaps even not too extremely costly, as at least
Geddes says that the sub quality is not important. (Which is one of the
questions that I have.)

As I was thinking about floor space, I suddenly had a spark of genius!
(Or perhaps not so much...) Is there a reason not to mount the multiple
subs directly under the ceiling?



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 (rewv5) *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
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[Mnyb]

Post by Gandhi
Seem reasonable. Perhaps even not too extremely costly, as at least
Geddes says that sub quality and power is not important. (Which is one
of the questions that I have.)
As I was thinking about floor space, I suddenly had a spark of genius!
(Or perhaps not so much...) Is there a reason not to mount the multiple
subs directly under the ceiling?

Build IB subs in the ceiling or under the floor or in the walls :)
http://ibsubwoofers.proboards.com/ hmm I'm not handy enough to undertake
such a thing



--------------------------------------------------------------------
Main hifi: Touch + CIA PS +MeridianG68J MeridianHD621 MeridianG98DH 2 x
MeridianDSP5200 MeridianDSP5200HC 2 xMeridianDSP3100 +Rel Stadium 3
sub.
Bedroom/Office: Boom
Kitchen: Touch + powered Fostex PM0.4
Misc use: Radio (with battery)
iPad1 with iPengHD & SqueezePad
(in storage SB3, reciever ,controller )
server HP proliant micro server N36L with ClearOS Linux

http://people.xiph.org/~xiphmont/demo/neil-young.html
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[Gandhi]

Post by Mnyb
Build IB subs in the ceiling or under the floor or in the walls :)
http://ibsubwoofers.proboards.com/ hmm I'm not handy enough to undertake
such a thing

I'd like to read that, but that link doesn't like me specifically(!).
Perhaps it lightens up a little later...



Best Regards,
Gandhi

not often enough well recorded and mastered cds *|* dbpoweramp with
accuraterip *|* flac *|* fanless asrock z77e-itx intel i5-3570t *|*
ubuntu 12.04.1 lts 32-bit *|* lms 7.8.0 *|* brutefirdrc 3.0 (rewv5) *|*
transporter (balanced out) *|* thule ia252b *|* audio physic scorpio *|*
no fancy cables. *+* also some booms. *+* harmony 525s for them all,
including waking the server from s3.
------------------------------------------------------------------------
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View this thread: http://forums.slimdevices.com/showthread.php?t=101723