November 2006 has seen the start of building a dedicated 2-channel listening room (a.k.a. "the man cave"). For the interest and benefit of others wishing to do likewise, I will try and relay details of the event that is expected to take 4-6weeks to complete.
* DESIGN
It all starts with a piece of paper and creative thinking of an audio designer which I found locally. Measurements were taken, consideration was given to room layout and planned speaker firing position. In my case I had two concrete block support pillars in the basement room and a lowish hanging support bean that sits atop the pillars. A structural engineer was called in to see about moving the posts and yes anything is possible with enough money . . . but the beams would stay put but be replaced by smaller footprint jack posts.
* ACOUSTICS:
The soundproofing would consist of Roxul acoustic and thermal insulation in the ceiling followed by Sonopan and 5/8" drywall to contain the sound. Special isolation clips for wall decoupling are used to isolate and 'float' the walls while rubber gasgets go between the concrete floor and wooden 2"*4" framing. J-molding, accoustic taping, 1/4" gasket for the ceiling/wall connection, air duct dampening material, insulated flex duct, external door with weather stripping were all used too.
* ELECTRICAL:
Four dedicated circuits will be installed: (i)a planned subwoofer on a 20 amp, 12 gauge Romex wired circuit, (ii) analog will also have a 20 amp, 12 gauge wire (in the event that my current 6watt/ch. amp gets replaced with a behemoth amp, (iii)digital will be a 15 amp, 14 gauge wired circuit, and (iv) a misc circuit for lights etc will also be 15 amp, 14 gauge. Isolated grounds will be created in the breaker box and plastic not metal recepticle boxes will be used to ensure only 1 end of the circuit is grounded (grounding both ends will cause the wire to act like an antenna!).
Planned future purchases include:
* Apple Mac Mini with silent hard drive and external RAID 1 disc storage for musical files
* Metric Halo LIO-8 Pro DAC
* Parametric EQ within the Metric Halo to tame the lowest bass mode peaks
I hired a small firm to design a dedicated music room in my unfinished basement which was no small feat. A contractor was hired to build it to spec and it was finished in January 2007.
Hemi-Cylindrical Diffuser / Bass Trap for Front Wall
A DIY hemi-cylindrical (poly) diffuser that doubles as a bass trap having OC701 fiberglass within its cavity. It's a 160degree arc from a 48" diameter Sonotube with red oak veneer on the exterior. The hard exterior diffuses mid/high frequencies in about a 110degree arc. With a total thickness of 30 inches, the hemi will absorb down to about 65Hz [1130/((30*7)/12)=64.6]
Front Wall Corner Bass Traps
A pair of DIY hemi-cylindrical (poly) diffuers that double as bass traps are in each corner. Eash is a 100 degree arc from a 48" diameter Sonotube with OC701 fiberglass in its cavity. They're covered with black speaker cloth to visually dissapear into the black coloured front wall. The total depth is 39" (27" radius + 12" air space) which absorbs down to about 49Hz. All hemi-diffusers can be pulled away from the wall to whatever depth is needed so as to tailor the low-end absorption.
Side Wall Reflecting Panels DIY
I built 3 reflecting baffles for each side wall. They are 3/4inches thick and run about 12feet long. Each baffle can be opened to any angle between 0 - 90 degrees. Right now the bottom baffle is open 30 degrees so that ear-level reflections are sent upwards to the ceiling diffusers, whereas the middle and top baffles are both open 20 degrees. The bottom baffle has a pair of GIK D1 QRD-like diffusers at each side wall's first two reflection points to help widen the apparent sound source width.
Skyline Diffuser for Rear Side Wall Treatment
A DIY Skyline diffuser for the rear right side wall. Uses 8 different cell depths in 1.5" increments with a maximum cell depth of 10.5". Being conservative, 10.5" is 50% of a 645Hz frequency which it will very effectively diffuse down to and likey another 0.5-1 octave lower. * Prime Number used = 547 * Primitive Root = 2 * 26 Columns * 21 Rows * 501 individual blocks of wood!
Hemi-Cylindrical Diffuser/Bass Trap for Rear Wall
Another two DIY Hemi-Cylindrical (poly) diffusers - one per back wall corner - to diffuse mid/high frequencies and absorb low frequencies as its interior is stuffed with OC701 fiberglass. Dynamat Xtreme (for car doors) was put on the hemi's inside to help reduce resonances and add stiffness. It's a 130 degree arc from a 48" diameter Sonotube.
GIK D1 QRD-like Diffusers for rear wall
6 are placed on the back wall (3 columns of 2) in front of 3 GIK Monster bass staps.
GIK Acoustics Monster Bass Traps for rear wall
3 total: Used on the back wall.
RPG Skyline (HP) Diffusers for Ceiling Treatment
9 Total: from speaker plane forward to listening chair.
RPG Skyline (LP) Diffusers for Ceiling Treatment
3 in Total: used on the dropped part of the ceiling between the front of the left speaker and the listening chair.
George Stantscheff Lightspeed Passive Attenuator
Passive attenuator that uses the special LDR (light dependant resistor) which has the ability to change it's resistance according to how much light LED (light emitting diode) is shone on it, hence it can control the volume without any mechanical contacts needed in the signal path. www.lightspeedattenuator.com
Art Audio PX-25
Fantastic sounding and very powerful despite being a 6 watt/ch. SET amp. With the KR Audio PX25 tubes and Sophia Electric 274B tubes and NOS input tubes.
FAB Audio Model 1
A 2.5 way with 1" tweeter and twin 10" drivers. High efficiency speakers (97dB).
Rythmik Audio F15
Two servo controlled subs each with a 15" driver and 370watts Class A/B each sub. Wonderfully musical.
Foundation Research LC-1
This is a bi-directional line conditioner filter and Cardas power cord all in one for the Audio Aero CD player.
TG Audio Lab HSR high purity silver interconnect
1.5 meter shielded
TG Audio Lab Speaker wire - silver
8 foot with spade ends
Audience PowerChord (4 foot)
4 foot power cord for Art Audio PX25 amp.
Dayton Audio OmniMic
Precision audio measurement system.
Sennheiser HD-600
headphones
StudioTech Component Cabinet U-22T
A rosewood cabinet with ventilation slots on the side, six shelves, cool looking doors and great WAF.
Wattgate 381 Ag AC Duplex Outlet
Audiophile grade AC repectacle. I bought two Wattgate 381's to be used on dedicated digital and analog circuits.
Thanks Kevin for your nice comments I have gone through many cables not sure if I kept the ones you're referring to .. then again I have a boatload of cables in my possession so I may still have them I eventually settled on Greg Straley cables as they do so many things well
GIK Panels helped considerably especially when the music is turned up. Bryan at GIK is great to deal with and very knowledgable.
Good to hear from you again ...perhaps one day we can hook up and hear each others systems in the not so distant future
Hi Musicfile, Nice to hear from you again. I see we both are GIK customers. Did you event end up getting cables from an upstart company in the US when I purchased your Audience power cord?
Your rig and room looks very good too I might add. cheers, kevin
System edited: Added more acoustic room treatments consisting of (i)5 Monster bass traps, (ii)8 D1 diffusers, (iii)4 242 mid/high frequency absorbers. It really is great how the sound of the room can be tranformed with treatments.
Elberoth2 and Glenfihi -- thanks for your notes and compliments. The up-front planning is indeed crucial. I had to deal with the limitation of a 7' ceiling height in my basement and two cement brick support posts that could either be replaced with slimmer steel jack posts (which I opted for) or for $2,000 - $3,000 I could move the posts farther apart. In the end the post positions within the room combined with the bulkhead around the support beam dictated speaker firing position across the short wall of the room and everything else spun off from there. It's a very quiet room even when the furnace turns on and blows hot air into the room. Thanks again.
Great planning and execution in building your room. I wish I had put as much into the details for sound proofing in my project. Your descriptions are good tips for anyone else looking to build a room for A/V.
System edited: Sold my First Sound Presence Deluxe MKII preamp as it was redundant with the preamp functionality within the Audio Aero Capitole CD player.
Before you do anything drastic, treating the room is a great idea. Check out the acoustics asylum, realtraps.com and rives.com for basic info. I got a great deal on custom made stuff from Sensible Sound Solutions. Brian reviewed my measurements, budget, etc. and he built bass traps and wall/ceiling panels which he shipped unfinished. He ordered wholesale Guilford of Maine cloth, drop shipped to me, and I cut/stapled/assembled everything from that point. IMHO, I spent $1k and got a $3k-$4k custom design. Check it out on my system page, "warming in the atma-sphere". Cheers, Spencer
Sbank (Spencer), Thanks for the compliment on the room. I plan on updating the pictures shortly. I was playing around with speaker positioning and measuring SPL levels with my Radio Shack meter and based on the uneveness I'd say the next move will be accoustic room treatments. While the system has come a long way, it feels like there is still a ways to go including better speaker cables, possible bi-amplification and adding a sub...
Kevin, Nice job on the room! It's amazing how few give it the attention it deserves. This is your most important component, and yours is a beauty. So what's the next move going to be? Cheers, Spencer
THE ROOM CONSTRUCTION IS FINISHED: The constructions has finished, the workers have left and the dust has settled. The equipment has been moved in and set up, at least temporarilly as future accoustic treatments may mean some minor positional changes.
Bottom Line: The system has never sounded better - no background noise to interfere with the musical details, dynamics and fun of the listening session. Let's just say that my wife is now an audio-widdow as I spend several hours after dinner in the music room.
The soundproofing works well and isolation of the walls from the ceiling and flooring means that my Radio Shack SPL meter measures about 30dB less on the kitchen floor directly above the room and even more attenuation upstairs in the bedrooms. The duct work treatment works really well as does the cold air return sound muffler. All this means that people can sleep or watch TV upstairs without being bothered by music.
Accoustic Treatments: As I have the speakers firing across the width of the room (13' 8" wide), first reflections aren't a problem as each speaker is about 7ft from a side wall and out about 50" from the front wall. The listening chair is about 2.5' from the back wall so reflections from the backwall are noticable especially when the volume is turned up and/or when the music is very busy with lots going on. Quadradic diffusion is planned for the backwall and should greatly reduce this affect.
Thanks Rugyboogie - I suspect that the glitz and glamour of equipment upstages the importance of the room itself for most people, at least it did me until I found a new house that would accommodate a dedicated music room.
The floor will be covered with underpad and low pile carpet and the ceiling will have somme treatments to it near the listening position. The front wall will have a "Polyfuser" made from wood while the back wall behind the listening chair will have a 12ft wide by 4ft high wooden quadradic diffusion. Side walls may have some first angle sound absorbing material. All in all I'm looking for a room that is neither too damped nor too alive.
Hi Kevin You are starting in the right spot with your system. THE ROOM itself and the construction methods. Can't wait to see it finished. Are you going to have any hard surfaces up front, floor or wall ?
System edited: Added audio room construction pictures. (1) Bulkhead has two layers of Sonopan and Roxul Safe & Sound insulation and will be finished in 5/8" drywall. It is important to prevent sound from making its way into the duct work and traveling throughout the house . . . (2) Bulkhead picture #2 shows the Roxul layered around the duct work to muffle sounds. (3) Extra sound absorption on AC outlets and light switch boxes. (4) New duct work to 4 rooms had to be constructed so as to push it up into the space between the first floor joists. The one heating duct for the audio room has (i) a few bends in it and (ii) is a special sound absorbing flexible duct to prevent sound from traveling back into the duct work and through the house. A special cold air return duct has been built like a muffler that requires several bends and is packed with Sonopan and special sound absorbing material. Construction To Do Items: finish drywalling, build out window ledges, install two exterior doors and seals, finish installation of electrical outlets and lighting, painting and carpet installation - most of which ought to be done by Christmas or early January 2007.
System edited: Today I replaced my Audio Aero Prima CD player with the Capitole MKII SE CD player. I also bought two Wattgate 381 Ag AC outlets to be used on dedicated circuits for digital and analog.
Music Room Update: * PLUMBING is finished - had to move hot water heater into another room and misc pipes had to run paralel to the bulkhead containing the supporting beams. * DUCT WORK has been finished by pushing them up into the ceiling caveties between the floor joists. A cold air return "sound muffler" is being built to absorb sound but let air pass. It's a series of staggered horizontal pieces of 2*4 that force the sound/air to travel in a series of 'S' turns with Sonopan sound absorption on all sides. Hot air return is with a special insulated flex duct and also has Roxul Safe & Sound and Sonopan insulation around it. * ELECTRICAL has been roughed in - need to wait for drywall to be in place before it can be finished. * FRAMING from wooden 2*4s is in place and to ensure the walls 'float' they reside on something looking like rubber underpad but made from recycled tires and are held vertically using a special clip that like a car motor mount uses rubber to prevent room vibrations from transfering to the walls.
This week insulation and drywall work will commence.
System edited: Changed the description of the system to reflect the fact that a dedicated 2-channel listening room is currently being constructed in my basement which will be 22'L*14'W*7'H.
Hi Mre2007, No I haven't pulled the trigger on a headphone amp (of any kind) as I've moved into a new/old home and will be finishing part of the basement as a 'music' room which'll be soundproof (or pretty darn near) which means the need for a headphone amp goes away. Orignally, I was going to get the headphone amp for late night listening so as not to awken the wife/kids but now the basement music room beckons . . . Do you own a SinglePower headphone amp?
