I figured you audio-nerds may appreciate an audio horror story. Please read late at night and in the dark… yikes!
I just moved to a new home… my downstairs is all mine! Butt… always that big butt in the room… the environment is turning out to be an acoustics nightmare. The first issue I had is connecting my Directstream DAC across the room to my computer via a long USB cable. Solved with an iogear powered USB extension cable. I have some stick on conduit on order… will run the cable on the ceiling-wall interface as there is a wall of glass sliding doors to deal with. Of course the fidelity of this long cable… well forget it, I need to get the signal across the room above all else. Remote USB connection update? Wireless connection?
Butt… here we go… I started playing music and hear a multitude of problems… The system is way too forward, hard, and lacks bass. So I redirected my PC’s audio out to the PS Audio drivers (usually bound to foobar) and used this on-line tone generator - and beheld the horrors:
Boy is this thing handy. Before I used various CDs with sweeps and selected frequencies and such but this generator is all you need. What did I learn? Whoa! I was getting massive buzzing, vibrating, and yes, howling… from… somewhere… where? Well I found it was coming from my fireplace. The darn thing is not the old fashioned system of heavy cast iron placed into brickwork. No, it is some sort of cheesy sheet steel cabinet with thin heat-brick things. The damper is a round “lid” that gets pressed into a round hole up inside the thing. This is just crap. The home was built in 1983, and I guess it was around then that these crappy systems were installed into homes.
Well the whole internal firebox resonates across a whole range of frequencies. Just horrible!!! Unbelievable actually. I just spent about 2 hours trying to dampen the noises. I plan on never using the stupid thing (my electric piano sits in front and across the fireplace) but I don’t want to damage its internals for obvious reasons. In short, I jammed a metal pole in there kind of pushing/bending its internals… then finally, I took some small real, wood logs and kinda rammed them up there to add a dampening mass to the various panels and joints. Sheeeeeesh!!!
Well it is mostly quiet now… for now. I’ve learned from chasing these resonances down they can return in surprising ways. Think the rattles and squeaks in your car. (BTW, the easist/fasted way to find those squeaks and rattles, is to use a tone generator on your phone piped through your car’s stereo… the evils will just pop out and you can get to work eliminated them).
How does the room sound now? AWFUL! starting at around 220HZ, the volume appears to drop rather linearly down the frequency scale. Anemic is a good way to describe the sound… just no bass to make it short. The good news is my Focal speakers can generate an audible sound down to around 25-30 hz or so… so the sound is there. Now how to get it out?
Stay tuned… I will be posting more as I progress.
How is the imaging? Kind of like a charcoal smudge on a black wall. Yea, that bad. The wall of glass on the right side of the room is just… argh…
Bruce in Philly (now in Atlanta)