speaker phase

[hasserl]

I've got to tell you, I'm pretty much at a loss here. It's am getting to the point where you are making no sense at all. Let's try to iron out exactly what the issue is.

If you are using one amp, what does it matter which channel plays forward or backwards...there is no "matching" unless you are using multiple amps/cabs...I don't understand what you mean by "matching", the amp either plays forwards or backwards...that's it. Both work, both will sound OK, just a little different.

It sounds like you're making my argument here. We are not talking about multiple amps, cabinets, or speakers being in phase with each other. We are talking about a single amp connected into a single cabinet (one speaker or multiple speakers in phase with each other). You say there is a difference between having the speakers connected to the amp one way verses the other. If you're talking about multiple amps or speaker cabinets then we're talking about different things here. I thought the issue was ONE AMP, into ONE SPEAKER.

the phase changes with channels, gain stages & other factors...but the cab is always "in phase" with the amp, just out of phase with specific stages.

This makes absolutely no sense. If the cab is always in phase with the amp, why would it make any difference which way the speakers are wired?

It is only out of phase when other influences dictate (multiple amps, cabs wired differently to each other). This seems to be the apart that you are overlooking.

Again, we are talking about ONE AMP only, not the relationship between two or more amps. ONE AMP & ONE SPEAKER. Right?

You say there is a difference in sound between having the speakers wired one way verses the other (there are only two ways, tip to positive/sleeve to negative, or tip to negative/sleeve to positive). Have I've described the topic correctly? Because if I haven't, then we are arguing different things and we might as well drop it here. But I do believe I've described what the OP was about.

Now, assuming we are talking apples and apples here (I realize the risk I take assuming something, I'll live dangerously here):

How can I not be insulted? People pay me to work on their amps because they trust my ears & judgement, I have worked hard & long, spending many many hours performing critical hearing tests, devloping my hearing skills

That doesn't make you immune to the power of suggestion. If you think you are immune to it, you are wrong. You are susceptible to it just as I and everyone else here is.

What exactly does "the science" say on the specific subject of a given speaker in a given amp sounding different, when the cone fires forwards when a positive signal is applied, compared to backwards when a positive signal is applied? Why do you need an explanation, what's wrong with a practical test?

The science says that trying to control when a positive signal is applied to the speaker is futile. I gave you multiple examples of why. You haven't given one rational explanation for any of those examples. You have absolutely no idea when you pluck a note on the guitar whether the fist impulse that hits the speaker will be positive or negative. If you think you do, please explain it. I'm thick headed, I need help here. With all of the variables I put out above, how is it possible that you could control whether the signal out from the amp is either positive or negative? Please, explain.

Prove it? How do you intend to prove what I can and can't hear? Why do I need to waste my time proving that there's a difference..

Why you would do it is because you are the one making a claim that defies logic. How you would do it is you would conduct a series of blind tests where you would play a guitar into an amp while someone else switches the phase of the speaker cable. You would not know which direction the phase was, or if it was even switched. If you can consistently identify the position or phase of the speaker cable you will have proven there is an audible difference that you can hear and identify. You'll have proven the phenomenon is real.

You have tried it once and not found a marked difference, fine, that's your experience...you could just say that, rather than questioning my integrity and proclaiming in a rather grandiose manner that you have "science" on your side.

I don't know how I've questions your integrity, or how I'm being grandiose. I'm merely making an argument against what you've claimed. I've given multiple examples of why what you claim should not be true, you haven't given one explanation of why it is.

[hasserl]

If you can't hear the effect in the room, why do you think that you will hear it better after being amplified, recorded, compressed, played back through the typical PC speakers?

YOU prove it doesn't make any difference.

The scientific method requires those making a claim to prove it, not asking the skeptic to disprove it. If the difference exists why should we not be able to hear it?

hasserl,
Can I just make a clip (or two) that compares them? It would be apparent enough in a clip.

Of course, now I'll have submit to the ridicule of my playing and my crappy sounding build.

Matt, the problem is, you'll know how the cable was set and it will influence your playing. You have to have someone else making the switching for you, it should be done so that you do not know when or even if they have switched the cable, and in fact there should be instances of where they do not switch it when you think they might have. You need to make it as close to a blind test, or even double blind, as possible.

[MattT]

So you would 'trust' an audio clip of this but you won't take my word that I can hear a difference? Obv I could 'fake' any audio test just as easily as I could lie...I have no reason to do either though. Or are you saying that I'm 'imagining' this difference and when 'put to the test' that I really couldn't hear the difference? Either I'm mistaken or I'm lying...or maybe the third option...maybe I really do hear the difference. And it's not a matter of; "Well I can hear a difference...if you can't it's because you have a tin ear." Nothing of the sort. If you have tried it and could not tell a difference then maybe it was not an issue with that amp...I've only tried it with my ODS clone and the difference was apparent.

I'm the one that's always telling everybody else how imperfect and biased we humans are. I'm fully aware of it and try use that information to make sure I don't make these kind of mistakes. There are some things that are apparent enough that I don't need a double-blind test.

Crap...now I gotta train the dog how to swap a speaker cable.

[hasserl]

Matt, I'm skeptical that there is an actual real difference. I'm not challenging your integrity, I'm not saying you're imagining things. I'm certainly not implying you would intentionaly alter the sounds. I do say that we are influenced in many subtle ways, sometimes we belive we hear, see, and even taste things that are not there.

As an example, I saw an experiment on TV where people were blindfolded and then given some plain unflavored yogurt, but they were told it was flavored with flavors like Strawberry, Lemon, & Orange, and they were asked to grade the taste of the yogurt. Afterwards they removed the blindfolds and learned the yogurt was unflavored. Every one of the subjects would have sworn that they were tasting the flavor that was told to them. Were they lying? No, of course not. The power of suggestion is stronger than you might think. I've seen wine tests where wine conisoures were given cheap wine and told it was very expensive, then they were given expensive wine and told it was very cheap, they reacted just as they were told, the power of suggestion overwhelmed their sense of taste.

I'm just saying that to do this right have someone else make the switches of the cable so that you don't know what they're doing. Don't you agree that would make a more interesting and beliveable result?

[woodyc]

Well, UPS just came with my DPDT footswitch. So far I've tried polarity reversal clean and cranked with a 65 Pro Reverb. I tried the amp with its combo speakers, and also with a 64 Bassman 2x12 closed back cab.

On the big questions of low-end and tone, so far I can't hear any difference whatever.

There IS a feedback difference, but personally I think its insignificant.

It shows up only if you have a note that is feeding back weakly or on the edge of feedback, and you push the phase switch, you can either increase or kill the feedback. This is basically the same deal as what happens with i.e. the feedback switch on a Fishman piezo preamp. You can't say that one polarity is better than the other unless you are only talking about a certain amplitude note at a certain distance from the amp.

Another interesting feedback effect is that if you have a note feeding back strongly, and you push the phase switch, you can actually hear the string change phase. It takes a second or so. During that time there is a slight lull in the level. However apart from the transistion, the feedback sounds the same with either phase.

Finally one weird procedural note. Because of the feedback phase thing, you have to stop playing when you switch. I was initially playing over the switching and convinced myself the tone was changing. It turned out it was just the phase of the ringing-note-feedback getting out of synch and then synching back up. If you stop playing for a few milliseconds during the switching, you don't get that effect at all.

[Alex R]

Finally one weird procedural note. Because of the feedback phase thing, you have to stop playing when you switch. I was initially playing over the switching and convinced myself the tone was changing. It turned out it was just the phase of the ringing-note-feedback getting out of synch and then synching back up. If you stop playing for a few milliseconds during the switching, you don't get that effect at all.

Aha...

[MWJB]

"The scientific method requires those making a claim to prove it, not asking the skeptic to disprove it. If the difference exists why should we not be able to hear it? " The scientific method requires a controlled, unbiased test (which would appear to exclude you and I from conducting the test). There is no "we" the question is whether "you" can hear it. If you can't hear it in the room, why would you hear it any better in a recording with a number of processes that skew the original sound?

Perhaps science can also prove why different cables with the same pf/ft and resistance between conductors sound different, what my faviourite brand of preamp tube is, how many sugars i like in my tea?

You build tube amps because you like the sound they make, you will set them up according to your taste...do you need science to "prove" how much plate voltage you like or do you arrive at that by ear?

For someone who is involved in a hobby incorporating so much subjectivity you seem bizarrely dependent on "proof".

"This makes absolutely no sense. If the cab is always in phase with the amp, why would it make any difference which way the speakers are wired?" How can the speakers be out of phase with the entrire amp, the speakers would cancel the signal from the amp. Amps can be out of phase with each other, channels can, speakers can BUT (now listen very carefully...for the last time) your cab is not out of phase with your amp...we are talking about a difference in harmonic content depending on whether the speaker moves forward with a positive signal, as opposed to moving backwards with a positive signal.

[MattT]

Just to be clear...I'm not saying there is a change in tone per se...just that it feedsback better one way vs. the other on my ODS clone. And as far as 'adjusting' my playing for each polarity...I wasn't really 'playing'...I was just lightly touching/hammering a note and letting it ring out...sometimes taking off sometimes not. I was just listening for which polarity had more feedback...if any...and my expectation was for there to be no difference. But if there was a difference...I had no idea which way would feedback better. That was part of the purpose of the test...not only to see if there was a difference but if so...which way sounded best.

So I think I was as unbiased as possible going into it...but just by virtue of doing the test in the first place implies that there was some sort of expectation...but I often perform tests like this just so I can honestly say; "I tried it and it made no difference."

[hasserl]

The scientific method requires a controlled, unbiased test (which would appear to exclude you and I from conducting the test).

No it doesn't. You obviously are not familiar with scientific testing and experiments. Nobody is ever without influences and prejudices. That's why you set up experiments to eliminate the subjective and concentrate on the objective. Effective experiments and tests should have good reproducibility and repeatability.

There is no "we" the question is whether "you" can hear it. If you can't hear it in the room, why would you hear it any better in a recording with a number of processes that skew the original sound?

See, there yo go with the typical argument of "you can't hear it but I can", that shows how weak your argument is. You haven't provided any explanation for any of the reasons I pointed out why swapping the speaker wires would make any difference, you just fall a tired old argument.

Perhaps science can also prove why different cables with the same pf/ft and resistance between conductors sound different, what my faviourite brand of preamp tube is, how many sugars i like in my tea?

You build tube amps because you like the sound they make, you will set them up according to your taste...do you need science to "prove" how much plate voltage you like or do you arrive at that by ear?

For someone who is involved in a hobby incorporating so much subjectivity you seem bizarrely dependent on "proof".

This is funny, you made a claim that something exists that logic says should not exist. When I challenged you on it, you feigned indignation and asked what science there is, so I gave it to you. Now, instead of explaining why that science is wrong you instead try to make fun of it and fall on the subjectivity of the hobby. Just goes to show the weakness of your argument. At least the guys on The Gear Page gave me good technical reasoning that I could even argue on their behalf if I had to. You've got nothing, NOTHING. "I hear it, if you don't too bad". You can't explain it, you can't prove it, but you believe it and are insulted if someone challenges you. Sounds like religion to me.

How can the speakers be out of phase with the entrire amp, the speakers would cancel the signal from the amp. Amps can be out of phase with each other, channels can, speakers can BUT (now listen very carefully...for the last time) your cab is not out of phase with your amp...we are talking about a difference in harmonic content depending on whether the speaker moves forward with a positive signal, as opposed to moving backwards with a positive signal.

OK, maybe the term phase is throwing you off. It's actually polarity that we're dealing with. But the effect is the same. You're convinced that having a positive signal move the speaker forward makes the cab sound better than a positive signal moving the speaker backward. If that's your only point, OK. Whatever. That's not the point of this whole thread and it is meaningless. Now you listen very carefully. My point is that the positive/negative swing of the output signal from the amp is constantly changing and only under very limited circumstances would things ever line up so that a pick or strum of the guitar strings would result in the initial swing of the output signal always being positive. In the real world the conditions change constantly and you cannot control whether the initial swing of the output voltage is positive or negative, it is what it is, due to everything from the initial note generated at the pickup, to any effects unit the signal is run thru, to the number of gain stages in the preamp. If you only play with a constant single picking motion, if you use no effects, if you have no channel changes, you might be able to set up your rig so that all output signals always start with a positive swing. But that is not practical in the real world, at least not in mine.

And that is the only thing that matters in this conversation, whether the polarity of the speaker wires causes the initial swing to move the speaker forward or backward. Otherwise the signal to the speakers is just an ac signal swinging at a frequency of around 100 times per second to several thousand times per second and a speaker vibrating at that same frequency. A pick of the string might start with the speaker moving forward, or it might start with the speaker moving backwards, it all depends on the things I've mentioned above (including which direction you've plucked the string, or whether the pickup is reverse wound reverse polarity).

[woodyc]

I tried a couple more amps, a Marshall 1987x and a Vox AC30CC2. Here’s a pic with the new phase switch in the foreground (which cost $43 with the cables and all.)

http://www.members.aol.com/wsjcrane/polarityswitch.jpg

As before at any particular location if you are on the edge of feedback there is an audible tone effect. But I haven’t found that one polarity produces either a better tone or more feedback generally. Also I have not found any evidence supporting Gerald Weber’s low end claim.

Alex R, I agree about the “Aha.” This is a very hard listening test. I can see a number of ways people could do what they think is a fair test and end up with a preference for one polarity.

Hasserl, I think you’re right about the picking technique, pickup polarity, effects, et cetera. It seems like the belief that speaker polarity matters creates a whole bunch of new things to worry about.

[Enzo]

OK, this is like the old AMpage now. This thread has become less about speaker phasing and more about the argument itself. A pissing contest in other words. The argument has become about itself. I'll wait in the hallway.

[pdf64]

Hey woodyc, I would be wary of switch the speaker with the amp putting out full power, as there will be a momentary open circuit while the contacts flip over, which will induce a big back emf across the OT primary, which could cause arcing over in the OT or tube bases. Just a note of caution, I'm not sure if that's what you are doing or not - Peter

[JC@]

...Aaaaargh...if you can't hear a difference it doesn't matter....if you can, then they way that sounds best!

...if you can't hear the difference, don't sweat it, but don't presume to tell me what I do & don't hear.

I can hear a clear difference.
I can hear a difference in aluminium frame speakers over steel sheet frame speakers.
To me phasing does matter a lot in some speakers, and not so much in others.
I've found speakers that will pull a lot better than push; let me explain myself a little better, in an unknown situation, I always use a cell battery, a weak 9volt one works because it is just a second, and I like to mark as "possitive" the pole that pulls to the frame and magnet direction. Then sometimes I reverse the polarity to see if it "pusshes" in the same ammount.

And I like pulling for guitar, and pushing for bass guitar, but that may well be just a matter of personal taste.