Sonics of Soundlabs

Keep in mind that the room dimension issues above apply to all speakers, not just Sound Labs. I have found that having the capability is more convincing regardless of the size of the room.

Also keep in mind that to drive Sound Labs you must use a tube amplifier for best results. If you use the VT 200, play with the taps on the transformer as you may be surprised by which taps to what to the sound. Generally Sound Labs, like most other ESLs, prefer a low feedback amplifier to get the most out them. This can get tricky as low feedback amplifiers generally will behave very differently depending on their output power and output impedance, but the speakers make it quite evident that taking this care is clearly worthwhile!

Atmasphere -- I believe I did mention that in my post :~)

These principles apply to all loudspeakers, not just Soundlabs. However most loudspeakers can't match both the output and frequency range of products like Soundlabs, Wilsons, etc. etc.

You guys have it backwards concerning room size. Once you get a wavelength that is longer than the room, you get what is termed room gain, on the order of 12db/per octave. (In an actual room it is less due to the walls flexing and losses through the walls, but the gain is there). Smaller rooms = more bass.

Mcreyn -- you are incorrect. When a half wavelength (~ 28 ft for a 20 cycle/sec tone) is longer than the longest dimension of the room, it cannot fully form in space before hitting a wall and reflecting. causing it to double back on itself, producing points of both cancellation and reinforcement. If you happen to be at one of the reinforcing points, it may appear that the bass is very loud, but just a few feet away there may be a null point with very little bass due to cancellation. Right at a wall surface, there is always louder bass because that's where the wave changes direction, therefore releasing a lot of energy when it momentarily stops before being reflected in the opposite direction. That phenomena happens in all rooms though, regardless of size.

If your analysis was correct, then shorter organ pipes would produce lower notes :~)

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You are speaking about standing waves, which is different than room gain. Room gain results from the maximum length of the wavelength being longer than the room. You do not have standing waves at frequencies below this fundamental frequency, only above. The way to compute the lowest resonant frequency of the room it to take 1127 (or if metric 343) divided by (longest room dimension x2). The result is the lowest freqency that you can have a standing wave and the knee freqeuncy below which you experience room gain.

You analogy of an organ pipe is incorrect as an organ depends on resonance to produce sound. This is far different than sitting in an enclosed area (a room) with a device that puts out an accoustic signal.

Here is a quote from Tom Noussaine on the subject:

"2. Room gain: Room gain starts at roughly the frequency of your lowest axial mode. The pressure gain is 12 dB per octave as frequency falls. In a car its at 60-70 hz depending on size. In my 2136 cubic foot older listening room it started at just below 30 Hz. In my 7500 cubic foot current room it starts at 16 Hz. A Velodyne FSR-15 had 8 dB less output at 2 meters in the larger room with idntical placement."

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