VTA ST-120 phase?

deepee99 wrote:Speakers don't know + from - or red from black, per se. It's that they're firing in phase that counts. Whether that's both red wires to both black connectors and both black wires to both red posts, it does not matter. The point is that they're supposed to be firing in the same direction at the same time.

Bob Latino wrote:I am with jfine on this one. In one system that I have downstairs I have a BAT VK30SE preamp. On the remote with this preamp there is a phase button. You can alternate the phase of the preamp by just pressing the button. On the preamp itself an led comes on when the amp is in positive phase. Running two M-125's on this system (which do have positive phase), the positive phase on the preamp does give a little more bass and a more natural overall sound. You can hear the subtle difference between the positive and negative phase as you alternate presses of the phase button.

Bob

jfine wrote:

Peter W. wrote:Expectations would cover that. Not to be snarky, "google" basic physics.....

Not sure what you mean by expectations.

How about this,

Instead of stating as fact, "As long as each speaker is hooked up in the same way, it makes no difference."

just add to the end

"...on my system, with my ears, in my room"

Since we all experience differently, it's impossible that what you state is true.

Tubes4ever wrote:
Bob,

Could the difference in sound be caused by the fact that the signal passes through a different electronic path?  Just wondering.  It seems you would need an active component to flip the phase.

Peter W. wrote:

If you expect something to sound different, you will be subject to confirmation bias. Under such conditions, that bias will supply the necessary differences.

OK – let us break this down into small steps for clarity:
• Consider the sine wave – ‘sound’ in its most basic form without any overtones.
• Let us set it, arbitrarily at 440 HZ (Standard pitch).
• Look at the form on a scope – a nice rounded wave to equal peaks and valleys going across “Zero” in a simple pattern.
• Let us agree for discussion purposes, and when the speakers are connected + to + and – to – , that when the peak is ‘above’ 0, the electrical impulse created by it pushes the speaker cone out.
• Conversely, when the peak drops below 0, the impulse pulls the speaker cone in.

So far, so good.

Now, connect the speakers + to –  and – to +. (Both of them, mind you!)
Now, the sine wave above the line (0), will pull the speaker cone in, below the line, push it out.
BUT – and here is where physics comes in – the speakers are still operating at 440 HZ, and the sound coming out of them will be indistinguishable from the previous option.
Point being that the speakers don’t care how they are hooked up, as long as they are hooked up ‘the same’ between them. They respond to the electrical impulses based on simple physics without any fuss or worry about its ‘flavor’.

Do NOT try this at home without understanding that a pure sine wave driven into a speaker at any volume for any significant period of time could damage the voice coil, possibly fatally. *ALL* the output energy is at that single frequency into a single driver.

Bob Latino wrote:

That could be true but I don't believe that is the major factor. What happens when you try to tell the difference regarding which phase sounds best or if there is any perceptible difference is the time it takes to swap the speaker cables + and -. You auditory memory is short and by the time you make the cable switch, you have lost most of the memory of what the first sound was like. With the phase switch on the remote on my BAT preamp, I can instantly compare the two phases and when you do that there is a subtle difference in the sound. I think that the difference is this > With a positive phase the leading edge of a transient sound is OUT into the room towards you. A cymbal sounds a little more real when the phase of your system pumps the leading edge of the transient towards you.

Bob