I have a couple situations where I’d like to place a single speaker rather than paired stereo speakers.
(These wouldn’t be my main speakers of course. For that I have a six speaker surround sound system.)
In one case it’s a small room elseshere in the house, and the other case is an outside speaker by my deck. I’d prefer not to have just one channel of sound, and I’d prefer not to switch to mono-output because I’d be using other main speakers at the same time.
Is there any problem with wiring the left and right channels together and using just a single speaker?
i don’t see any. just remember to turn the power to the speakers down as when a sound is on both channels it will be doubled in power. on that speaker. there might be a little audio distortion too.
I think what you’re proposing to do is sort of what’s referred to as a bridged mono. One thing you should be concerned about is whether or not the speaker can handle the output. For instance if your amp puts out 100 watts per side and your speaker is rated for 150 watts then you run the risk of ruining your speaker since both sides combined equal 200 watts. That’s kind of a rough explanation but you get the idea.
I do. Even if you properly wire it with (+) to (+) and (-) to (-) there’s no guarantee that the actual audio signals will always be in phase. If it is, fine, at worst you’ll have a minor, but probably not catastrophic, impedance mismatch. However, if the signals are out of phase by around 180[sup]o[/sup] you may end up putting a rather large voltage differential across the final output transistors, especially at higher volume settings. Best to buy (or build) some type of mixer to safely combine the two signals.
Hmmm. I didn’t consider the “double the watts” potential problem. Would the left and right channel wattage really be additive?
Regarding a mixer, I certainly don’t have the knowledge to build one. Googling results in either professional mixer equipment or how to set up or record in surround sound.
(sigh) It appears that my simple solution is not so simple.
I did that with a center channel speaker…I wired the left and right into it…the receiver blew, the people at the repair store said it was a “massive power surge” that was caused by wiring the center channel that way…the fuses failed to protect it.
It ended up being cheaper to buy a new receiver than get the old one fixed.
Let’s say you’re listening to Led Zeppelin and most of Bonham’s drums are coming out of the left channel. The bass drum requires a lot of cone displacement, which means it’s represented by short bursts of (relatively) high voltage going to your left speaker. In the right channel is Page’s guitar, which requires relatively low voltage going to the right speaker.
When you hook up both channels to one speaker, you are putting these two channels in parallel. This means that at every given instant there can only exist one voltage common to both channels. But as described above, each channel can have a different voltage. So you sort of have a tug-of-war going on here. Which side will “win”?
The answer is actually quite complex, so I won’t go into it. But I suspect you see the problem. As a first-order approximation, we can assume the high voltage spikes from Bonzo’s drums will be imposed on the right channel. The right channel doesn’t want these spikes. The end result is that you could end up cooking the some output transistors, and perhaps even fry the power supply.
Q.E.D., you continue to amaze me. (Heck, now I even believe that .9999… = 1 ) Thanks. I’m trying to find out how much these things cost, but it doesn’t look like it’d be too expensive.
i stand corrected. i have done i before with no real problems. the sound was a little distorted though. even simple looking things can be full of risk it seems.
Actually, if the output channels are modeled as voltage sources (which is usually a good approximation), and if the channels are in phase (as would be the case for mono), then hooking up both channels to one speaker would not give you any more wattage.
For most amplifiers, “bridging” is not done by putting the two channels in parallel. Instead, one speaker lead is connected to positive bias while the other lead is connected to negative bias. (In stereo configuration, the negative lead for each speaker is usually at common, or close to it.)
Bad idea. Not to mention you would still not get Stereo in the rest of the speakers as you have shorted both channels together. Better use the Mono setting.
Another thing you can do is this: Suppose the speakers are 8 ohms. Take two 4 ohm resistors of adequate size and connect them in series with one end connected to one channel and the other end to the other channel. Now connect the speaker between the common resistor connection and the common speaker connection. In other wortds, the circuit is like a T.
netscape 6, I did this too at my first house, with cheap components and never had a problem. Now, 20 years later with much better equipment I thought I’d do a little research before attempting the same thing again. Good thing, it appears.
Boo, smoke huh? Talk about an *un-*subtle indication of a problem.
mack, I neglected to recognize your reponse. Your explanation was clear and concise.
I bought a wireless 900 mhz outdoor speaker at best buy. It hooks up just like a component and brings both channels into the single speaker. It took some fiddling to get the level output right, but once I got it right, it sounds very satisfactory for a wireless…although a wired will sound better…then again, outside on a deck isn’t exactly a prime autistical setting.
Question: Would the 30 watt RMS stereo to mono mixer (in Q.E.D.'s link) be sufficient to handle what I’m sure is more than 30 watts per channel out of my receiver?
does your receiver not have a mono/stereo switch?
just set it to mono…then hook either the left or right channel into the one speaker… in mono mode there will be no diff between the 2 channels
Here’s another real-world problem. There’s a DVD player, which of course, outputs in stereo, and a mono TV. Now, I’ll be danged if I only listen to one channel of audio coming through that TV, and I have no other easy way of getting sound except from the TV speaker. My solution has been to bridge the mono, but then take it through a mono adaptor and then into the TV. This has fixed it so that when I plug in my headphones, I have sound coming out of both earpieces (even if it is just an illusion, it’s far less annoying than only getting one channel.) Could I blow a fuse or take out the TV with this setup?