- May 27, 2021
Nothing is (usually) calibrated at home. Movie theaters are calibrated (for a certain seating position) and pro recording studios are calibrated. There is a standard for calibrating your home theater but I suspect it's too loud for everyday use so most people probably turn it down, loosing the calibration (for everyday listening).This is what's frustrating, if you have several inputs being used in the KEF Wireless 2, optical/wifi/Bluetooth/HDMI/analog input, I doubt the input volume is all the same especially for the analog input.
Both. They are pretty-much interchangeable except that headphone outputs are capable of driving headphones (lower impedance) and headphone outputs always have a volume control, whereas line outputs sometimes don't.I don't even know if the KEF Wireless 2 analog input is for headphone or line level, given it's a regular 3.5 mm stereo jack.
Turn it up to whatever level makes you happy and if you aren't hearing distortion everything is good!I think the only real way to measure it is to look at the spec sheet, see the power output at the amp output, do some math and figure out the DB value if you're using a preamp to your amp. Line levels are not constant with preamps and with active speakers, what the heck are we supposed to do with different sources coming in?
With specs & testing we are concerned with the peaks which are higher than the average loudness. The short term peaks aren't necessarily perceived as "loud" or "louder", but they can cause audible distortion if you push your amplifier or speakers into distortion. Bass also requires more power (and big woofers). Amir made a video - How loud is loud?Why are we testing speakers at 96db and 86db? I can't imagine most people listen to speakers above 60db. Is it just marketing to get better noise measurements?
I've never used REW but once you've loaded the calibration file you'll get accurate readings. ...But I don't know if there's a setting for A-weighting like a regular SPL meter.1. What settings I should use for accurate SPL readings in REW using the UMIK-1 with calibration file?
No, because everybody has a volume control.2. Is there a math equation I could use and what is it if I'm outside of an SPL meter when listening to speakers outside of my home such as a store and friends house? I had believed most potentiometers are either linear or logarithmic.
Double the power is +3dB.3. Given that most tests are at 1 meter from 1 speaker vs 2 speakers, how much more DB does 2 speakers vs 1 make when determining loudness when making a speaker buying decision?
The inverse square law says double the distance is -6dB. (That's "worst case" outdoors with no reflected sound.)4. Given that most tests are at 1 meter, what difference in db does distance make as you go past 1 meter?
The noise from an amplifier or active speaker is (usually) constant. So it's more noticeable with silence or low volumes and the signal-to-noise ratio gets better at higher volumes.5. When looking at the optimal loudness for volume, does noise generally go up at lower volume levels for amp noise but goes down for speaker noise?
If you have a preamp (or other source) with a volume control, the noise from the preamp generally goes up-and-down when you change the volume. But it depends on where the volume control is in the chain. Of course, adjusting the digital level doesn't affect any noise generated on the analog side.6. If using a physical preamp or streaming wirelessly (Bluetooth and wifi), does noise generally stays constant at the preamp to amp stage. If this is true, shouldn't we max out our preamp or streaming minus a few DB to stop clipping at the DAC or preamp input, to reduce noise at speaker output? In other words nearly max out Bluetooth or preamp analog input signal to get the least amount of noise to the speaker?
Resonance doesn't change with volume but it might seem worse at higher volumes. Good speakers shouldn't have any noticeable resonance.7. Does speaker cabinet resonance go down as volume goes down or is it linear or logarithmic or just random based on volume level?