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.
Hi Rugyboogie - thanks for the kind words. It's been a fun and educational experience. I still get out the Dayton OmniMic and play around with things - more tinkering than anything else.
I love your room and equipement too! I see you own a grand piano - are you the pianist? I take it you're an Oscar Peterson fan as one of your pictures in your Totem system has a caption with his name in it. When I was a young lad my parents took me to the Burlington Public Library (west of Toronto) to see Oscar Peterson play in the basement which was a free gig. He was INCREDIBLE. He demonstrated to us different jazz styles of playing. He had the audience yell out the names of a few notes which he then used to improvise a song on - UNBELIEVABLE! I think Keith Jarrett is a great improviser but Peterson is just as great or better, in my opinion.
Hi Lapierre - Let me address your questions in reverse order. (1) I use the Dayton Audio OmniMic acoustical measurement tool. (2)Regarding subs, if you have only one listening position for a single listener then theoretically one sub properly placed should suffice. Given that your room has the same width & length dimensions you might need a second sub and/or parametric EQ to attenuate the bass peak(s). Adding a second sub isn't about getting louder sound but rather more even bass reproduction. My left sub has been raised 4ft off the ground to greatly reduce a ceiling induced null at the listener position whereas my right sub sits right on the floor and has slightly different frequency and volume settings than the left sub so as to optimize the bass at the listening chair. (3) Are you planning on hanging a bass traps on the backside of your door? Alternatively the best bass trap is to leave the door open!! Regarding the bifold doors and closet, can you put traps inside the closet or build a stand with wheels to put bass traps on in order to swing it into place when you listen? I've found that mobility of acoustical treatmenets is critical as there is much positional adjustments required.
Hi Kevin Long time no talk. The room that you have build looks absolutely amazing. Very well done, must be thrilled with the results both sonically and visually. Congrats and all the best to you in the new year.
My back wall has a plan (check my system) for two bass traps. The corners have a door and closet with bifolds--that sucks-- which makes adding additional bass traps and diffusors difficult. I can easily add bass trap to the back door but what should I do with bifolding doors? Listening position is pretty close to the back wall and about 8 feet from loudspeakers.
The other question concerns subs. You have two 15" subs. My room is only 12x12 with one REL sub. Not sure I will add a second sub to balance things out. What do you think?
What software are you using for room measurements?
I'm sure you have heard it before, but its my turn to praise the construction of your room. Few do it and most should, especially with elite gear. I'm sure you are reaping the benefit that your audiophile gear can offer. I can imagine the listening experience you are immersed in. Congrat!
Hi Lapierre - thanks for your comments. I'm using two Rythmik F15 subwoofers, one on each side wall just slightly behind the listening chair for best bass response. The PX25 amp is wonderful and even though it only has 6watts output it's a good match for the 97dB efficient full-range speakers. And of course the gear - any gear for that matter - sounds best when the room is taken out of the equation via acoustical treatments.
Hi Devilboy, Like the new system you're rebuilding, I currently own the Lightspeed passive preamp, tube amp and high efficiency speakers and quite like to sound of it, especially the PX25 tube. To answer your question I've not had other passive preamps to compare the Lightspeed to.
Thanks for the nice words on my system! I, however, no longer have most of the equipment you saw. I am currently rebuilding my system: passive preamp, tube amp, high efficiency speakers. Question: Do you still have the Lightspeed? I'm strongly considering this preamp just from the overwhelmingly positive comments on it. Have you had a chance to compare it to other passives?
System edited: just added some updated pictures, including the GIK D1 diffusers on the side walls and the reflective baffles behind them. It may not be anyone else's cup of tea but I love the colour of the baffles against the black walls . . .
The planks seem like a great idea. Looks great and no doubt helps with reducing reflections.
I have seen this type of decorative treatment in classical concert halls. In classical music halls there is a tendency to for reflective surfaces rather than absorption, as this helps with ambiance and audibility.
System edited: Just finished building and installing reflective side wall panels that are adjustable from 0-90degrees to eliminate flutter echos, reduce comb filtering, and reflect upwards sound to the ceiling RPG Skylines to raise the soundstage height. In short, the side wall oak panels create a reflection free zone and preserve the MF/HF liveliness without the use of absorption panels. Added new photos.
Shadorne - many thanks for dropping by and for your compliments. I return to view your room from time to time too as its a great looking (and sounding I'm sure) room.
Musicfile (Pat) - Sure, I'd love to see and hear the changes you've made. Are they equipment related or room layout related? I don't know if I know my room issues stuff any better than anyone else here, but a 2nd set of ears provides another data point for you to consider. Send me an email and we'll arrange something. I want to finish off v2 of my room before you come over, ok?
Version 2 of the room has a few changes: -> Front Wall: the 3 Hemi's (centre, and in each corner) remain unchanged. I've added one GIK Monser on the front wall on either side of the centre Hemi to absorb the rear reflecting 1st reflections from the speakers. It deepens the soundstage.
-> Side Walls: 3/5" planks of Oak wood are running horizontally for most of the length of the room. The top plank is 12" wide, and the centre and bottom are 24" wide. The tops of each board are affixed to a 2"*4" using piano hinges which means the bottom edge of the boards are free to be pulled away from the wall as much or as little as desired. I'm using doweling to provide infinately adjustable angles for the boards to be 'open' or 'closed.' Using trigonometry I have the top and middle board at a 20degree angle and the bottom board at a 30degree angle. Still more listening tests and other angles will need to tried and contrasted. The angled boards eliminate slap/flutter echos, maintain the mid/high frequency energy within the room, and allow the apparent sound source width (image broadening) to be tailor-made depending on the angle.
->Back Wall: the two side wall hemi's have been moved to the back wall corners and a new Skyline diffuser will be made to fit the new wall size and will likely have 21.8" deep cells, which is 50% of a 311Hz wavelength. Should sound even better . . . I hope.h
Hi Kevin I hear you're revamping the room again Version 2.0 I haven't even heard version 1.0
I made a few changes myself I was wondering if you had some time to come over and have a listen You seem to know your stuff when it comes to addressing room issues
01-16-11: Bigby Great looking system and acoustic treatments. Id love to hear the impact of the skyline diffusers. If I ever get to Canada, Ill give you a shout....
Thanks for the kind words Bigby. Your room doesn't look too shabby either ;)
The Skylines raise the ratio of direct-to-indirect sound being heard so you hear more details etc. I'm currently redoing my room - Version 2.0 - and will be moving the side wall hemi-cylindrical diffusers to the back wall corners and building a new Skyline for the back wall that will have much deeper cell depths to allow low frequency diffusion. The beauty of DIY allows custom stuff to fit your room and its limitations (e.g. seating distance to diffuers in my case).
