DIY: 10 hints for inexpensive Home Cinema room setup and sound acoustic improvements

Discussion in 'Members DIY Home Cinema Showcases' started by Marc71, Jun 10, 2016.

  1. Marc71

    Marc71
    Novice Member

    Joined:
    Jun 8, 2016
    Messages:
    15
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    4
    Location:
    Europe
    Ratings:
    +6
    Challenges:
    1. Bare minimum sound equipment with decent sound reproduction.
    2. Improve the sound acoustics of an untreated living room.
    3. Reduce the echo time in a rectangular small room.
    4. Inexpensive and visually-friendly sound treatment of the walls.
    5. Save floor space by using on-wall mounted speakers and subwoofer.

    For those of you who want to hear and compare the sound difference between treated and untreated room; watch this quick video demonstrating the sound effect of echo reduction.


    P1020014 Panorama.jpg
    Hint nr.1
    Room treatment using inexpensive acoustic panels. Try using expanded cork boards for sound insulation and echo reduction. The expanded cork boards are used for noise isolation and they are produced from raw materials with many small granules forming a low density and a fine texture to the surface. Recommended for echo reduction and noise isolation in rooms, the expanded cork reduces the echo levels and achieve a sound absorption and acoustic treatment in theater halls, concert halls, schools, receptions halls and other rooms where it's necessary to reduce the echo.
    The cork boards come in various sizes and thicknesses and are easy to cut to dimension with a utility knife. For this room I bought a pack of 12 sheets x 1.50m by 0.50m which cost around $300. All cork boards you see in this room were made from that 12 pack. Of course, the cork boards aren't the perfect echo reducing solution on the market that one can buy. There are other better and more professional sound boards out there, but they cost way more and they aren't as easy to customize (size wise and color wise.)

    P1020027 Panorama.jpg
    Hint nr.2
    Decorate the cork panels. I've used the same wall paint base in which I've mixed some different colors (they can be bought in small tubes).

    P1020035 Panorama.jpg
    Hint nr.3
    Pay special attention to the ceiling as it's usualy the largest echo producer in any room. The ceiling is a huge echo generator. Cover at least the main reflection points of the ceiling with expanded cork boards. It will considerably reduce the echo and enhance room's sound quality.
    P1020063-68 Panorama.jpg
    Hint nr.4
    The furniture should be made exclusively from natural wood. Avoid any glass elements (table tops made of glass, etc.)
    P1020081-85 Panorama.jpg
    Hint nr.5
    The couch's (sofas) upholstery: avoid leather or skin imitations which are echo generators. Velour or thick fabric are preferred as they better absorb sound.
    P1020058.jpg
    Hint nr.6
    Avoid fireplaces: they have many sound reflection points and glass front panels that are echo generators.
    Hint nr.7
    Cover all windows with curtains or drapes as thick as possible. Cover any reflective surfaces made of glass or metal.
    P1020062.jpg

    Hint nr.8

    Rugs and carpets should be made of natural materials (avoid carpets made out of polyester). Here weight is very important: the greater the weight the more it will absorb the sound. In my living room I've got two hand-made wool rugs with the weight of 4200 gr./sqm.
    Hint nr.9
    Position your subwoofer close to a room corner. I've mounted my sub on the wall, with the bass driver firing towards and bouncing of the wall - check out the square white box decorated with green stick-on gem decals. It's a conversation piece :)
    P1020105.jpg
    Hint nr.10
    Use on-wall speakers in small spaces.
    DLS is a Swedish brand of speakers specializing in manufacturing slim-line on-wall speakers for serious audio enthusiasts. Their properly designed speakers can potentially outperform its freestanding in-room counterparts. DLS on-wall speakers are true on-wall monitors, while the DLS Flatbox Large ($1200/pr.) + DLS Flatsub Midi subwoofer ($500) combination offers a compelling and well-priced alternative to large floorstanders. Years ago I used to own a pair of B&W 220 floorstanding speakers and I can say these DLS speakers have very similar sound characteristics to those B&W monitors but in a smaller, on-wall format.​

    P1020095.jpg
    Here's a quick way to check for the echo level: hold a tall drinking glass in one hand. In the other hand hold a metal teaspoon. Tap the glass with the teaspoon several times while you're walking around in various parts of the room. If you'll hear anything more than a clean and neutral "cling" (generated by the glass), you need to reduce the echo that is arriving in that particular spot.

    My Gear:
    Yamaha RX-V479 Wi-Fi AV network player & receiver
    Sony BDP-S7200B Blu-Ray Player 3D 4K Wi-Fi
    Front speakers: DLS Flatbox Large (Sweden)
    Surround speakers: Taga Harmony TOS-315
    Subwoofer: DLS Flatsub Midi
    TV: Philips 49PUS7100-12
    P1020106-119-b Panorama.jpg
    Room Specs:
    Location: ground floor of a 10 story-high condominium building
    Surface: 190 sq. feet (17.7 sq. meters)
    Length: 17 feet (5.20 meters)
    Width: 11.16 feet (3.40 meters)
    Room height: 8.2 feet (2.5 meters)
    Build: concrete walls.

    Thank you for reading. Have you built a home cinema or improved the sound in your home's audition room? What materials and sound gear did you use?
     
    Last edited: Jun 12, 2016
  2. BM08

    BM08
    Active Member

    Joined:
    Jun 24, 2012
    Messages:
    885
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    46
    Location:
    West Midlands, UK
    Ratings:
    +165
    That looks fantastic, love the colours you've used and what you've done to the room.

    Great tips and advice aswell, I'm sure it could help a lot of people out.
     
  3. Marc71

    Marc71
    Novice Member

    Joined:
    Jun 8, 2016
    Messages:
    15
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    4
    Location:
    Europe
    Ratings:
    +6
    Thank you BM08.
     
  4. geogan

    geogan
    Well-known Member

    Joined:
    Nov 28, 2005
    Messages:
    1,274
    Products Owned:
    25
    Products Wanted:
    12
    Trophy Points:
    117
    Location:
    Ireland
    Ratings:
    +597
    Lovely interior design you did in the room there.

    I should really do this. I have an Ikea table in front of the couch that has a glass table top and I'm sure it causes some sort of comb filtering coming from centre speaker which I have to leave more or less on ground level under screen.

    Of course - that's how Dolby atmos upfiring speakers work :)

    Very hard to avoid fireplaces when every single builder in my country puts one by default in the sitting room even if you don't want it - if I had my way when I bought the house new I would have left out the fireplace altogether - it even gets in the way of placement of PJ in centre of room.

    Similar size to mine 4.8 x 4.8 x 2.5

    I wonder exaclty what frequency range the cork boards actually attenuate - i'd say it is just the high frequencies - as we all know low bass frequencies are almost impossible to attenuate without huge amounts of very dense material.

    As you said, if you do anything at all then the side, floor and ceiling first reflection points would be the places to start to improve dialog reproduction from center.
     
  5. Marc71

    Marc71
    Novice Member

    Joined:
    Jun 8, 2016
    Messages:
    15
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    4
    Location:
    Europe
    Ratings:
    +6
    Hi @geogan, thanks for the compliment.
    Regarding your Ikea glass top table; one way to improve things is to cover it's edges with U Shape Glass Table Corners:

    U Shape Glass Table Corners.jpg

    ...then cover the top with some felt (or other kind of) table protector. When use in tandem, they'll do wonders when it comes to sound reflection and distortions.

    Felt Table Protector.jpg

    > Of course - that's how Dolby atmos upfiring speakers work :)

    Well, in theory, the Atmos up-firing speakers should work nicely. However, while being an 'old-school' kind of listener, I say the audiophile sound quality is such an intricate, delicate and personal-sensitive matter that I would not dare to entrust my sound coming from any reflective surface, including...the ceiling. I come from the group that believes listening to reflected sound is like watching sexy movies instead of doing it in real life ;)

    > Very hard to avoid fireplaces when every single builder in my country
    > puts one by default in the sitting room even if you don't want it

    Solution: custom build a cabinet (furniture) around the fireplace, then cover it with sound proof materials - including cork.

    > I wonder exaclty what frequency range the cork boards actually attenuate - i'd say it is
    > just the high frequencies - as we all know low bass frequencies are almost impossible
    > to attenuate without huge amounts of very dense material.

    Indeed, that's the situation regarding bass frequencies attenuation. For the rest of frequencies have a look at this graphical representation:

    Acoustic cork panels sound absorption comparison.jpg

    P.S. Love your selection of high quality "L"-class Canon zoom lenses :cool:
     
    Last edited: Jun 21, 2016
  6. geogan

    geogan
    Well-known Member

    Joined:
    Nov 28, 2005
    Messages:
    1,274
    Products Owned:
    25
    Products Wanted:
    12
    Trophy Points:
    117
    Location:
    Ireland
    Ratings:
    +597
    Well the Ikea glass table i have actually is made of wood with wood all around the edges - the glass is just in the middle so you can see down into the drawers under table.

    Yes if I went for Atmos myself there is no way I would ever use up-firing speakers - I would install real speakers in ceiling.

    Your sound absorption graph is as I thought - I'm just surprised that a lot of people don't understand this and think 3cm of material will knock 100+ dB from their subwoofer output and stop it going through a wall to neighbours - it's ridiculous. Low frequencies are very difficult to control and attenuate in an enclosed room. The mid/highs are much easier to control.

    As you can see from that graph the corkboard is the worst and that's for 4cm thick material - if it is only 1cm thick it will be much worse. And who is going to stick 4cm thick board on the walls of their living room? Would be only acceptable for a studio or dedicated theatre.

    Most of the furniture and curtains in a normal room does a good enough job of damping down a lot of the high frequency reverberation, as anyone will notice when they walk into a brand new "show house" type empty room and hear how a room with no absorption whatsoever sounds like. Once a normal amount of furnishings goes in, the room "deadens" down a lot compared to bare concrete room.

    Also a 5.1 system I think will be fine at low to moderate volume levels in an average room - it is only when the volume is increased to near reference levels that all the reverberation from untreated surfaces will muddy the sound to a severe degree and cause loss of direction to sound as all the reflected waves are strong enough to hear from all directions. This is what makes the loud volume tiring to the ears more than the actual volume itself.

    Yes L-series are great lenses - if only I could use them with my GH4 camera (can't afford Speedbooster right now :()
     
  7. Marc71

    Marc71
    Novice Member

    Joined:
    Jun 8, 2016
    Messages:
    15
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    4
    Location:
    Europe
    Ratings:
    +6
    Hello @geogan, thanks for your input.

    > Low frequencies are very difficult to control and attenuate in an enclosed room.
    > The mid/highs are much easier to control.

    Yes indeed, you're right. The low frequencies are quite difficult to attenuate in an enclosed room and just some 3 cm (or so) of cork definitely won't stop a subwoofer's output going through a wall to neighbors. For that purpose, however, there are some more expensive and time consuming treatments available out there.
    In this particular project, my challenges were listed in the beginning of the article.
    I've aimed for (just) an inexpensive and visually-friendly way to sound treatment the walls. Of course - if more time /money /desire would have been available - then, the results would have been closer to ideal. But, that wasn't my initial goal, and I can say that I'm quite happy with the end results - at least for now. Of course, that might change in the future :)

    >Also a 5.1 system I think will be fine at low to moderate volume levels in an average
    > room - it is only when the volume is increased to near reference levels that all the
    > reverberation from untreated surfaces will muddy the sound to a severe degree and
    > cause loss of direction to sound as all the reflected waves are strong enough to hear
    > from all directions. This is what makes the loud volume tiring to the ears more than
    > the actual volume itself.

    You've just written a good description of what happens to the sound in an average size room. And again, I agree. With the reserve that, the term "near reference levels" might mean different things for different listening 'subjects'. For example I know some folks who won't complain about loss of sound direction or echo effect as long as it's playing their favorite tune. I'm glad that me and you aren't in that kind of croud :)

    > Yes L-series are great lenses - if only I could use them with my GH4 camera (can't
    > afford Speedbooster right now

    I was also looking into Speedbooster for coupling the great Canon's 24-105 L lens with my Panasonic GM5 camera, but I think I'll just end up getting a simple MF3-rds adapter.
    Anyway - as a long time Canon EOS aficionado - I think the mirorless cameras are the new thing to get into.
     
  8. geogan

    geogan
    Well-known Member

    Joined:
    Nov 28, 2005
    Messages:
    1,274
    Products Owned:
    25
    Products Wanted:
    12
    Trophy Points:
    117
    Location:
    Ireland
    Ratings:
    +597
    I meant the "supposed" standard that all AV amps have where you can change the volume display to the (dB) version where reference level ends up at 0dB on volume control but normal movie listening level will be from -20dB to -10dB (mute on mine is at -80dB). If you ever try and listen at 0dB in a normal room it is not comfortable at all. The 0dB here is supposed to be calibrated by manufacturer to be the reference level - whether it is or not I don't know o_O

    Yes like those poly-clip systems but people still think they do massive attenuation with bass but they don't at all - if you read or look at the manufacturers graphs you can see they only attenuate maybe 30 to 50dB on low end still (even with multiple layers on both sides of walls and multiple layers of plasterboard and green-glue) so you are still getting over 50dB of bass going through the wall if you started off with 105dB of bass :laugh:

    I actually had a loan of a similar glass-less adapter from Metabones (so I could use EOS lenses with my GH4 while my GH4 lens was in for repair) but to be honest the quality ended up being terrible - way worse than I expected - it was like the lens couldn't focus or it was a fuzzy focus or something - that was with the Canon 24-70L 2.8 and 16-35L lenses on it. I was very disappointed with it.

    Isn't that what my GH4 is? :)
     
  9. geogan

    geogan
    Well-known Member

    Joined:
    Nov 28, 2005
    Messages:
    1,274
    Products Owned:
    25
    Products Wanted:
    12
    Trophy Points:
    117
    Location:
    Ireland
    Ratings:
    +597
    ps. have you ever used the audio analysis software REW (Room EQ Wizard)?

    It's very good for this sort of thing if you have the required measurement mics... look up "waterfall" graphs and how you use them to see how the reverb is doing before and after treatment in a room.

    Also does a good new room simulation feature for placement of speakers/subs in room and seeing peaks/nulls at listening position in room for those speaker positions.
     
  10. Marc71

    Marc71
    Novice Member

    Joined:
    Jun 8, 2016
    Messages:
    15
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    4
    Location:
    Europe
    Ratings:
    +6
    Hello @geogan,
    > ps. have you ever used the audio analysis software REW (Room EQ Wizard)?
    For this budget-limited simple project I haven't use it - however REW room EQ is on my list (together with other tools) whenever I get a demanding job.
    By the way, I appreciate your knowledge and good understanding of sound and image processing.
     
  11. geogan

    geogan
    Well-known Member

    Joined:
    Nov 28, 2005
    Messages:
    1,274
    Products Owned:
    25
    Products Wanted:
    12
    Trophy Points:
    117
    Location:
    Ireland
    Ratings:
    +597
    Oh I didn't realise you do this sort of thing professionally
     
  12. RXP

    RXP
    Active Member

    Joined:
    Apr 5, 2005
    Messages:
    349
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    28
    Ratings:
    +31
    I love the look of your room!

    One inexpensive tip for those with projectors - use thick velvet curtains. Completely deadens the room and improves contrast. I recently did this and you can immediately tell the room has been deadens because when you talk it just sounds different.
     

Share This Page

Loading...
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice