Speaker Phase

[Reeltarded]

Playback polarity does make an audible difference in a studio monitor system, and is most noticeable on drums.

rd

+1

[martin manning]

Just thinking about the kick drum as an analog to a speaker... If the listener is in front of the kit, the initial attack of the drum is always a positive pulse followed by a rapidly decaying oscillation. Would it sound different if you were to turn it around and listen from the rear? Probably.

[C Moore]

As Tom said, this has been discussed here quite a few times in the past. Dogears has stated, paraphrasing here, that he can, without any doubt, hear the difference in phase in a double blind test.

I am not being a smart-ass, a "doubter', or disrespectful of somebody with a lot more experience than myself......
I know he SAYS he hears it in a blind test.....but I would like to see it. I would want to be the guy flipping phase, and have him tell me....maybe 10 times in a row....which is which.
Again....no disrespect at all....but if he can hear it....he can identify it....right.?
If I can see a difference between Blue and Yellow, taste a difference between salt and Pepper, pedal easier on the Flat rather than on the Incline.....I should be able to tell somebody else when it happens. Is that not correct.?
At this point, I have not seen anybody do that with a guitar and amp.....but I read/hear them say they can. Maybe some guys can.....I don't know.
I have been told a lot of "things" on this forum. Usually in the pretext of asking for help. I have been able to take those suggestions, and see the effect. But speaker phase.....I myself cannot tell a difference.
Best

[husky]

I did run in to differences in Combo amps when the phase was flipped on the speaker. There can be an interaction between the speaker and the tubes if they are in close proximity.

[vibratoking]

I am not being a smart-ass, a "doubter', or disrespectful of somebody with a lot more experience than myself......
I know he SAYS he hears it in a blind test.....but I would like to see it. I would want to be the guy flipping phase, and have him tell me....maybe 10 times in a row....which is which.
Again....no disrespect at all....but if he can hear it....he can identify it....right.?...

Sounds like doubting to me. I am not being a smart-ass either, but I would suggest to avoid stating the you are not a 'doubter' and then writing statements of doubt. For the record, I have yet to hear or identify any difference in phase either, but I also believe what Scott reports.

...At this point, I have not seen anybody do that with a guitar and amp.

Nor have I, but just cause you haven't seen it doesn't mean it doesn't exist. BTW, I don't have a dog in this fight, but I'm keeping my mind open to the possibilities.

[Lynxtrap]

Playback polarity does make an audible difference in a studio monitor system, and is most noticeable on drums.

rd

+1

Yes, but that is not what we are talking about now. You can run several speakers out of phase, in a cab, in the studio, live, and it will make a clear impact.
Your studiomics might be out of phqse qnd you discover it when listning to your in-phase monitors, or even in mono.
You can run guitar through a 2x12" cabinet and that one of the speakers is out of phase with the other.

But IMHO you can't play guitar trough one speaker and claim it will sound better if you reverse

[Richie]

There is a difference in how they sound. But mostly when you think of phaseing of speakers. 2 or multiple speakers out of phase with each other will sound thin and weak. Probably similar to that out of phase sound in the strat between pickups.

What i think makes the difference which i might have spoke about on other forums about this. Is the cab or its construction.

And anyone can try this with their amp or cab. The cab will have an effect of how the speaker works. I noticed this many years ago working on fender amps. I'm not saying all of them, but every one i've came across in an open back combo was wired so the speaker moved inward.

On unported 4x12 cabs, they were wired so the speaker moves out. I have swapped them in both cabs,and could hear a difference. So i always stuck with this,and would wire the open back or combos to move inward. And sealed 4x12s direction or phase to move out.
Some people think of open back combos or cabs as filling the room. And i think the direction or movement helps or makes a difference to make this happen.
Sure it will work either way, but try it and listen for yourself. You might like it one way or the other. I don't see its a law. Or you may find a different response in the feedback or reaction of the guitar and speaker. In other words, not only things you hear, but how it effects holding notes among other things.

The sealed back cabs. Speakers move air,and if they are moving inward,the air inside the cab does not have a place to escape. Except blow the speaker cable out of the jack. I think someone posted about carrying 2 different wired speaker cables for a cab. That way they could flip the phase with just a cable. I'm sure it depends on the amp too. Some are reversed phase from the OT.

I'm sure someone has the technical info to really answer for sure. But sometimes its best to just grab your gee-tar,and try it and listen. If you hear or fell a difference,change it. If not, you had fun trying.

[husky]

Here is a story my friend Jim Kelley told me about with a combo when we chatted about it.

Fender tweed Bassman that I once worked on.
The customer had his speakers reconed and reinstalled by someone. Then he brought the amp to me to go through it and get it back into playing condition. I did whatever I did to it, I don't remember, and I sound tested it while the chassis was still on the bench. Sounded effing great - amazing. Maybe the best amp I've ever heard. So I put the chassis back in the cabinet and gave it one last sound test. It sounded like total crap. I couldn't believe it. So I pulled the chassis back out and tried it again, and it was awesome again. I put the chassis back in the cabinet and it sounded like crap again. This time I didn't bother taking the chassis back out. The only thing that was different was the proximity of the chassis to the speakers, and I noticed in particular that the output tubes we pretty close to one of the speakers. So I checked the wiring and noticed that somebody had reversed the wires from the speaker plug at the point where they join with the wires from the speakers. I connected black to black and white to white and the sound quality returned to being amazing.

===

Now when I made Eric Claptons Tweed Twins I also noticed the speakers were flipped on his original Diaz modded amp. I reversed the amps and switched the new amp to being "correct". That amp didn't sound as spongey when putting them both on an AB switcher (two combos) Same speakers. Although of course many factors that could be different but I thought I nailed it. I switched the speaker phase on the new one and that was it. They then sounded identical. I chalk it up to an interaction between the power tubes and the speaker or the OT and the speaker but whatever it really was not subtle.

[Richie]

did you note the direction they moved? That was one of the amps or a few of those i noticed. I've had a few tweed bassman amps. So i started looking at the others too. So i figured their was something to it.

[paddy]

removed post

[Reeltarded]

I'd rather be pushy than suck real hard.

[Firestorm]

The only thing that was different was the proximity of the chassis to the speakers, and I noticed in particular that the output tubes we pretty close to one of the speakers.

Awww John... I've been fighting with a 5F1 that sounded surprisingly lifeless. Should have been totally cool: everything was tip-top. Even had a new Weber Signature Alnico ... 1/3-inch from the 6V6!

Did I just reinvent this circuit for no reason?

[Lynxtrap]

These stories seem to make "the myth more plausible"
But I still don't understand it. You'd think that it would have been investigated and explained by someone over the years.
Some kind of feedback seems to be the only logical explanation. But speakers push air, tubes work with voltages. How can they interact? I want to know!

Here is a story my friend Jim Kelley told me about with a combo when we chatted about it.

Fender tweed Bassman that I once worked on.
The customer had his speakers reconed and reinstalled by someone. Then he brought the amp to me to go through it and get it back into playing condition. I did whatever I did to it, I don't remember, and I sound tested it while the chassis was still on the bench. Sounded effing great - amazing. Maybe the best amp I've ever heard. So I put the chassis back in the cabinet and gave it one last sound test. It sounded like total crap. I couldn't believe it. So I pulled the chassis back out and tried it again, and it was awesome again. I put the chassis back in the cabinet and it sounded like crap again. This time I didn't bother taking the chassis back out. The only thing that was different was the proximity of the chassis to the speakers, and I noticed in particular that the output tubes we pretty close to one of the speakers. So I checked the wiring and noticed that somebody had reversed the wires from the speaker plug at the point where they join with the wires from the speakers. I connected black to black and white to white and the sound quality returned to being amazing.

===

Now when I made Eric Claptons Tweed Twins I also noticed the speakers were flipped on his original Diaz modded amp. I reversed the amps and switched the new amp to being "correct". That amp didn't sound as spongey when putting them both on an AB switcher (two combos) Same speakers. Although of course many factors that could be different but I thought I nailed it. I switched the speaker phase on the new one and that was it. They then sounded identical. I chalk it up to an interaction between the power tubes and the speaker or the OT and the speaker but whatever it really was not subtle.

[martin manning]

These stories seem to make "the myth more plausible" But I still don't understand it. You'd think that it would have been investigated and explained by someone over the years. Some kind of feedback seems to be the only logical explanation. But speakers push air, tubes work with voltages. How can they interact? I want to know!

The flow of electrons in the tube can be varied by changing the mechanical spacing of the elements. Since the internal structure is not perfectly ridgid, acoustic waves from the speaker can cause the elements to vibrate, and the relative motion between them could occur in such a way as to either reinforce or diminish the output in the same way as electrical feedback. Resonances are likely to occur, which would increase the effect at particular frequencies. A microphonic preamp tube is a familiar example of this phenomenon. A magnetic field can also cause the electron flow to change, and the magnetic field produced by the speaker coil could have a similar effect. However, I think the strength of this field would be quite low outside of the speaker structure.

[Lynxtrap]

The flow of electrons in the tube can be varied by changing the mechanical spacing of the elements. Since the internal structure is not perfectly ridgid, acoustic waves from the speaker can cause the elements to vibrate, and the relative motion between them could occur in such a way as to either reinforce or diminish the output in the same way as electrical feedback.

Yes, but that effect would be "uncontrollable", unlike electrical feedback, and seems unlikely to have anything to do with speaker phase, IMO.