2-Channel vs. Stereo

[PrActical_AV]

Is there a difference between 2-channels and stereo? I am wondering because some components have a switch that says stereo and 2-channel? Also, a lot of mixers have stereo inputs or you can use 2 of the channels (one panned hard left and one panned hard right) for stereo. Is there a difference in how it's wired? What about the sound quality? Is one better than the other.

[Craig Vecchione]

Stereo refers to two signals that are not identical. 2-channel would likely mean the same as "dual-mono" which means two identical signals amplified separately. For an amp, dual-mono or 2-channel would typically allow you to use one input jack, which is split to feed the two amp channels. In stereo, the inputs would remain discrete.

[karlw]

 

Stereo refers to two signals that are not identical. 2-channel would likely mean the same as "dual-mono" which means two identical signals amplified separately. For an amp, dual-mono or 2-channel would typically allow you to use one input jack, which is split to feed the two amp channels. In stereo, the inputs would remain discrete.

 

 

I don't agree with that description. "Stereo" to me means that the system or component keeps the two channels separate but processes them identically. For instance, you might have a stereo input and stereo channel on your mixer. When you apply EQ, you are applying the same EQ to both channels. When you bring up or down the level, you are doing so to both channels.

 

"2-channel" would mean that although you have two channels (like stereo), you have independent control over them. You can EQ each channel separately. You can change level separately, etc.

 

A 2-channel power amp would have two gain levels, one for each channel, allowing you to use them separately, i.e. perhaps one for a sub channel, one for a mid-high. And in many cases, such amps allow "bridging" which means you can run the two channels together as one channel (like described above). But a "stereo" amp such as for home hi-fi, would have one volume knob affecting both channels simultaneously.

 

Hope this helps.

 

-Karl

[Craig Vecchione]

 

I don't agree with that description. "Stereo" to me means that the system or component keeps the two channels separate but processes them identically. For instance, you might have a stereo input and stereo channel on your mixer. When you apply EQ, you are applying the same EQ to both channels. When you bring up or down the level, you are doing so to both channels. "2-channel" would mean that although you have two channels (like stereo), you have independent control over them. You can EQ each channel separately. You can change level separately, etc. A 2-channel power amp would have two gain levels, one for each channel, allowing you to use them separately, i.e. perhaps one for a sub channel, one for a mid-high. And in many cases, such amps allow "bridging" which means you can run the two channels together as one channel (like described above). But a "stereo" amp such as for home hi-fi, would have one volume knob affecting both channels simultaneously. Hope this helps. -Karl

 

 

The context of discussion is sound reinforcement amps. What I described was some of the ways SR amplifiers are designed and labeled, which are in general different than the ways home hi-fi is built.

 

2-channel and stereo, in SR, are fundamentally identical. Two amps, two inputs, two outputs. But in order to provide more flexibility, the amps' inputs and outputs may be manipulated in various ways to provide stereo, dual-mono, parallel-mono, bridged-mono output, parallel-mono-output, etc. without external hookup wiring changes. In general, however, there are few SR amps that offer single attenuator control during stereo in/out operation. This is usually reserved for parallel mono operation where one input feeds both amps, and one channel's attenuator affects the signal to both amps.

[karlw]

 

The context of discussion is sound reinforcement amps.

 

 

If that's true, then why did the OP write:

 

 

Also, a lot of mixers have stereo inputs or you can use 2 of the channels (one panned hard left and one panned hard right) for stereo. Is there a difference in how it's wired? What about the sound quality? Is one better than the other.

 

 

?

 

-Karl

[Craig Vecchione]

Sorry, Karl, Sound Reinforcement gear, vs home hi-fi.

[karlw]

Craig,

 

I totally agree that SR and home HiFi stuff is completely different, and I wanted to point that out. At the same time, the way amps are set up and labeled and the way mixers are set up and labeled is also different. - another one of my points. I'm not totally sure what the OP is looking for, but by this point, he's got something to mull over!

 

-Karl

[PrActical_AV]

Thanks Karl and Craig, that sure is a lot to "mull over". I guess my interest boils down to am I missing something or gaining something hooking up my sources using 2 seperate channels or using a "stereo" channel to get a stereo output.

 

One point brought up is the independent adjustments (volume, eq, etc) that using 2 seperate channels has versus the single adjustment over 2 channels using "stereo".

 

The reason this got me thinking about the whole stereo vs. 2 mono channels (panned R/L) is that over the weekend someone was hooking up a DAW to record an live event I was doing and wanted to know if he should record the drum overheads in stereo or use 2-channels (L/R). I immediately said use the 2-channels (L/R) because the you would be able to vary the volume, position, and eq of the two channels independently. He then commented on how a "stereo image" might be lost if he didn't use the "stereo" channel. So that triggered all the thinking about how stereo vs 2-channel plays in all my gear (amps, mixers, processors, etc). Is there some type of "magic" that happens using "stereo"?

[agedhorse]

If labeling was more consistent, there would be less confusion.

 

Not unlike the meaning of "diversity" in the wireless receiver world where it means different methods of (trying) to achieve better reception due to 2 physically seperated antennas. Different manufacturers do it differently, some even within different models in their product line. Some methods are more effective and have less artifacts than others.

 

Karl, your version of diversity is IMO better functioning than a lot of what passes as diversity in the marketplace, especially when you compare to the sub-$400 products!!!

[karlw]

 

He then commented on how a "stereo image" might be lost if he didn't use the "stereo" channel. So that triggered all the thinking about how stereo vs 2-channel plays in all my gear (amps, mixers, processors, etc). Is there some type of "magic" that happens using "stereo"?

 

 

No magic, other than a "stereo image" is the result of A) some kind of stereo microphone arrangement, then B) having those two channels processed the same. You can achieve the same results with the two mono channels as long as you mirror the processing - use the same EQ setting, gain, etc. However, it's important to consider the fact that a "stereo image" may not be needed or even desired. If you started out with two different mics on the drums, or did not have them set up in a stereo pattern of some sort, it's not a "stereo image" in the first place. Or even if it was, you may want to process the two channels differently in order to arrive at the desired mix.

 

That's my take on it, anyway.

 

-Karl

[Craig Vecchione]

 

Thanks Karl and Craig, that sure is a lot to "mull over". I guess my interest boils down to am I missing something or gaining something hooking up my sources using 2 seperate channels or using a "stereo" channel to get a stereo output. One point brought up is the independent adjustments (volume, eq, etc) that using 2 seperate channels has versus the single adjustment over 2 channels using "stereo". The reason this got me thinking about the whole stereo vs. 2 mono channels (panned R/L) is that over the weekend someone was hooking up a DAW to record an live event I was doing and wanted to know if he should record the drum overheads in stereo or use 2-channels (L/R). I immediately said use the 2-channels (L/R) because the you would be able to vary the volume, position, and eq of the two channels independently. He then commented on how a "stereo image" might be lost if he didn't use the "stereo" channel. So that triggered all the thinking about how stereo vs 2-channel plays in all my gear (amps, mixers, processors, etc). Is there some type of "magic" that happens using "stereo"?

 

 

Nope. In the case of the gear you're describing, as long as you hard-pan one channel left and the other channel right, the stereo image is preserved the same as a stereo input channel, and you do gain the benefits you mentioned.

[karlw]

 

If labeling was more consistent, there would be less confusion. Not unlike the meaning of "diversity" in the wireless receiver world where it means different methods of (trying) to achieve better reception due to 2 physically seperated antennas. Different manufacturers do it differently, some even within different models in their product line. Some methods are more effective and have less artifacts than others. Karl, your version of diversity is IMO better functioning than a lot of what passes as diversity in the marketplace, especially when you compare to the sub-$400 products!!!

 

 

Of course part of the problem, especially with things like "diversity" is that marketers have worked hard to drill home their particular version of these things. In the case of diversity reception, it was understandable at the time to make a distinction between "true diversity" (i.e. two independent receivers each with an antenna, then some kind of switching or panning circuit) and the quasi-diversity systems of the time (two antennas hooked up to one receiver, sometimes even without phase switching).

 

Now days, there are a number of different and highly effective ways to implement antenna diversity. And then of course there are still the companies doing cheezy stuff. I suppose that will never change!

 

-Karl