Preamp inverts signal.


My tube preamp inverts the signal and the manufacturer suggests to reverse the speaker leads at the speakers to correct. My CD player has a polarity switch, will activating this switch take care of this signal inversion, avoiding having to reverse speaker leads?
phd
My CD player has a polarity switch, will activating this switch take care of this signal inversion, avoiding having to reverse speaker leads?


Yes.
Thank you, that's all I wanted to know.
Better still listen with and without and decide what sounds best. In my system with a DCS player and non inverting amps 99% of CDs sound better inverted so I leave my CD player set that way. The vast majority of LPs however sound best non inverted but I always check and where needed can switch from the amp.

Tell tales for an inverted recording is often recessed bass and thin mid range and when you switch you can tell straight away which way is better. Many recordings however have a mix of polarities so there's no real difference. Net net try it both ways. You will find lots of discussion n this topic elsewhere on this site
folkfreak, thank you for the in depth information! I will try that.
Good responses above.  A point I would add is that when the setting of the switch is changed you are not only changing the polarity with which the recording is reproduced, you are also changing the circuit configuration of the component in which the switch is located.  In some cases you might even be inserting or removing an active stage from the signal path. 

So you may find that one setting is usually preferable to the other one simply because the component sounds better that way.  At least, that is, if the inversion is performed in the analog domain rather than the digital domain, which is usually the case in preamps but perhaps not in your CDP.

Regards,
-- Al
 
Al, your tech info is always appreciated.
My pre inverts phase,   I just invert the speaker polarity.  Although my DAC can invert phase I want the phase correct with all sources.  
oddiofyl, that makes a lot of sense. Anyway can't one reverse the polarity at the amp instead of the speakers, same thing right?
folkfreak -

if inverting makes 99% better, and CDs have a mix of polarity, how is that possible?

My Sony HAP server supposedly inverts and I always wonder about swapping leads, but if so many recordings are inverted, it's a random thing, no? 
Fact is CDs do not have a mix of polarity, the vast majority are inverted. Lots of coverage of this online, the link below is to one of the most well known sites.  Changing polarity on my Paganini is a pain so I set it inverted for the majority, I try not to use the polarity change switch on the amp if I can as as another commentor pointed out it does change the active circuit. Just occasionally I find an LP that benefits however, for example yesterday on the "Breaking Glass" S/T (no great recording but inverting really helped)
http://www.absolutepolarity.com/

What is interesting and a little mysterious in George's very thorough explanation of absolute polarity is that entire CD LABEL repertoire are inverted polarity which seems to rule out randomness of CDs being inverted polarity. Mapleshade is an exception but on George's list the big boys like Mercury Living Presence and RCA Living Stereo CDs and Deutsches Gramophon are inverted polarity. So, ensuring one's system is polarity inverting might actually be a very good idea if his taste runs toward classical music. My only nagging reservation is that nobody else has confirmed George's list as far as I know, which does show an overwhelmingly high percentage of CDs having inverted polarity. I do find myself much preferring analog versions of RCA Living Stereo recordings including cassettes over the CD version, but it's difficult to say whether the reason fir this preference can be attributed entirely to the difference in absolute polarity, but I'm open to the idea that it might be a lot of the reason.

Phd,  I invert it at the amp side, makes no difference though 
Allrighty boys, today I’m swapping speaker leads and hope I don’t burn the house down ;) will report back in a few days. Wish me luck, going into the bush.

Sidebar, how can I test my system for polarity? Test track? 
"Sidebar, how can I test my system for polarity? Test track?"

The most reliable way to test the system for absolute polarity is the in phase and out of phase tracks of the XLO Test CD. Of your system is in the correct absolute polarity the Out of Phase track will sound like it is coming at you from all around the room with no specific direction. And conversely the in phase track will sound like it's coming from dead center and be very focused. These effects are much more pronounced with proper speaker set up and after careful attention to room tuning. 

Geoff Kait

Geoffkait 03-20-2016 7:17am EDT
Of your system is in the correct absolute polarity the Out of Phase track will sound like it is coming at you from all around the room with no specific direction. And conversely the in phase track will sound like it’s coming from dead center and be very focused.
The description of "out of phase" in the first sentence is the effect of relative polarity being wrong, not absolute polarity being wrong. In other words, it is the effect of having the output of one speaker out of phase with respect to the output of the other speaker. Which would be the result of having + and - reversed in the connections to one speaker (but not both). The effects of incorrect absolute polarity (having the outputs of both speakers inverted, relative to the polarity that is presumed to have been received by the microphones during the recording session) are vastly more subtle, and may be imperceptible on most of the recordings that have a mix of different polarities for different instruments and singers.

Phd, thanks for the nice words.

Regards,
-- Al

My Croft 25R inverts but reversing speaker leads dulled the dynamics enough to be noticeable. I put them back to the way they are marked. I tried this with a number of recordings and results were consistent. 
Al, unfortunately phase and polarity are sometimes used interchangeably. In the case of the XLO test CD when they refer to "phase" they're actually referring to what we call absolute polarity now, you know, what with the book on polarity by Clark Johnsen and the work in the past ten years by George Louis.  Obviously one should not misconnect cables. If one speaker is out of phase due to miswiring the out of phase track will not sound correct.

cheers

"My Croft 25R inverts but reversing speaker leads dulled the dynamics enough to be noticeable. I put them back to the way they are marked. I tried this with a number of recordings and results were consistent."

Is it possible something else in your system inverts polarity?  Two wrongs make a right.

Not every listener is sensitive to absolute polarity.  And even if a listener prefers one polarity over the other it doesn't mean the preferred setting is the "correct" polarity.

In a typical recording session the engineers pay attention to phase issues, but not to absolute polarity.  In fact, nearly every mic preamp and mixing console has a polarity switch for each input channel.  These switches are freely used which can result in a multitrack recording where the drums have one polarity and the piano another.

In a purist, true stereo recording absolute polarity takes on more importance, but for most modern recordings I don't think it's a major factor.  Someone may have a definite preference for how they have set up their system, but I think Almarg's comments about circuitry is probably a better explanation for one's preference.
Onhwy61 wrote,

"Not every listener is sensitive to absolute polarity."

>> I never said they were. Some people hear better than others, no doubt about it. And there are exceptions to every rule. I suspect it’s probably true that people need to be trained to listen for the difference between N and R, otherwise they tend to not know what to listen for.  Just like distortion or say transparency or grain or whatever. Everyone should go out and and find a guru. ;-)

Onhwy61 also wrote,

"And even if a listener prefers one polarity over the other it doesn’t mean the preferred setting is the "correct" polarity.""

>>I never said it did mean that. People frequently don’t know what the heck they’re listening to half the time, don’t you think? No one actually thinks about polarity when he’s listening. Only if he’s testing for polarity. And then he has to do the test correctly, no? It’s a little more complex than you let on. Most likely 99% of audiophiles do not think about polarity EVER in the course of a year. But that doesn’t mean polarity is not an issue or is a non-trivial one.

"An ordinary man has no means of deliverance." ~ Old audiophile expression


GeoffK, very possibly. It's a fairly straightforward path. I'll go with what sounds best though.
Another factor is the design of the loudspeakers playing any given recording. Very few are phase-coherent; planars are, of course (one reason for their generally high-quality sound), but most multi-driver dynamics are not. Vandersteens yes (at the x/o frequency, at least), Wilsons no. The drivers’ polarities may be inverted relative to one another, in order to optimize the speakers frequency response and/or waterfall plot performance. If that requires running one driver with inverted polarity, so be it. Dave Wilson, for one, does that regularly. The Eminent Technology LFT-8b magnetic-planar and Vandersteens models 1, 2, and 3 use 1st order (6dB/octave) cross-overs between drivers, and are phase-coherant. If you are listening to a speaker which has it’s drivers working in opposite polarity, good luck listening for a change in absolute polarity upstream.
I must say that I was never troubled by polarity of a recording. Have inverted polarity at the speaker or amp end of their terminals at times when amp or pre were inverted. Guess i am not that trained in listening. Also mayby thankful for that.
Yes...BUT!
As long as it is your only source.