Is doubling speakers +3dB or +6dB? What's parallel and series wiring?

This is the kind of audio content we need on YouTube. Very informative.

Eskimos have been hooking their woofers up in series parallel configurations for hundreds of years.

Great video was taught this on a Rockford Fosgate amplifier and system design course 30yrs ago, first time seen such good explination of it :)

Easily one of the best video’s regarding this subject I’ce ever seen, keep the good stuff coming 👌🏼

Very good video! Reiterating old knowledge and this was perfect, thank you.

What determines whether two signals of equal amplitude combine to produce a 6dB gain or a 3dB gain in signal level (voltage or SPL, but not power), is the “correlation” of the signals at the point of combining. FULL CORRELATION CASE: If the correlation is 100% between the two source signals at the location where the combined signal is being measured (the two source signals are received with identical amplitude and with identical phase) then a 6dB gain in level (SPL or voltage, but not power) is achieved. Example 1: Two side by side subwoofers which are both fed the same signal (with the same amplitude and same phase) and which are both equal distant from the measuring device. In this case, the measurement device will measure a “combined” signal which is 6dB higher in SPL than that measure by either subwoofer alone. For a sine wave signal source, the two source signals would always have their sine wave peaks “synchronized” and always providing a doubling of peak level. And we know that a doubling of level (voltage or SPL) results in a level gain of 6dB. However, it is important to note that the “power” delivered to the room is only 3 dB higher than that delivered by either subwoofer alone (a doubling of power results in a gain of 3 dB). NO CORRELATION CASE: If there is no correlation between two non-identical, but equal amplitude, signals at the location where the combined signal is being measure, then a 3dB gain in level (SPL or voltage) is achieved. Example 2: Two side by side subwoofers are fed pink noise signals generated from two different noise generators (the pink noise signals are not correlated). In this case, the measurement device will measure a “combined” signal which is 3dB higher in SPL than that measure by either subwoofer alone. The two signal’s peaks and valleys will only be in alignment part of the time. And over time, the signal alignment of the peaks will vary between in phase (0 degrees) and out of phase (180 degrees). And the average increase in SPL or Voltage signal level achieved will be 3db higher than that delivered by either subwoofer alone. MAINTAINING 100% CORRELATION ISNT ALWAYS EASY Even in example 1 above, if the SPL meter where to move around the room, the path length from each subwoofer to the measurement device would change differently for each subwoofer, and the correlation between the two signals being combined would not stay at 100%. The axis of the room where the measurement device is equidistant from the two subwoofer will always receive the 6db gain in SPL. But there will be some locations in the room where the path length from each subwoofer would result in a 180 degree phase shift at the measurement device, and the signal would be cancelled. But most people, who are not equidistant from both subwoofers would experience a 3 dB gain in SPL. Another interesting example is the case where two signals of varying phase are combined. Example 3: Two side by side subwoofers are fed sine wave signals from two different signal generators (one at 60 Hz and one at 61 Hz). In this case, the measurement device will measure a “combined” signal which varies in SPL reading over each one second period. For one instant in each one second period, the measurement device will measure a “combined” signal which is 6dB higher in SPL than that measure by either subwoofer alone. But AVERAGED over the full second period, the measurement device will measure a “combined” signal which is 3dB higher in SPL than that measure by either subwoofer alone. In summary, achieving a 6DB gain in SPL with two subwoofers only occurs where the resulting phase difference between the two identical subwoofer signals at the measurement position is near zero degrees.

Nice explanation of parallel vs series wiring with visual examples! I think anyone studying electronics or amateur radio should check out this video. Nicely done!

The Best info I've taken in since trying to understand thanks

Incredible clear explanation, thanks buddy !

Thank you. I was curious about this.

Awesome explanation.

Great video!

Sehr gute Erklärung. Danke!

Great video.

Nice! This, along with many of your other lessons and demonstrations, should be mandatory study requirements for all "Audio People", especially live performance types!!! Most of them are clueless and believe myths of their predecessors, urban legends, hearsay and of course: "that's the way it is, everybody knows that!"

So far, the best video I've watched in the 36hrs I've been trying to understand about speakers. I have these 5.1 speakers I found in our basement with it's player already disposed of that I want to use as a pc speaker, and I'm trying to learn how I can install them when there's just one front and one rear 3.5mm headphone/speaker jack, though it's got a sound card that supports up to 7.1, for the life of me, I have never been interested in electrical wirings until now. I don't how I can wire them all into one jack, or do I need to install another sound card with more ports, or buy some whatnot to connect them to. If they get more expensive than buying a pc speaker, they're going back to where they came from, useless. I'm going to follow you from now on and learn.

Actionable intelligence, I love it!

very helpful, thank you very very much!

Nice Honda Clarity. Love mine

Extremely educational just came across your channel. Exactly what I was looking for all this type of information