geoffkait
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May Belt
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Hi Geoff.

One of the most experienced listeners I know (i.e Martin Colloms in the UK) has just written an interesting observation on the subject of Absolute phase in Hi Fi Critic – under the heading “James Boyk piano recording and absolute phase”

Being aware that some LPs and CDs and even different tracks of the same disc can present problems regarding absolute phase is extremely important and, unfortunately, not everyone struggling to get good sound has that awareness – even though it has been a subject reported on for decades.

Regards,
May Belt,
PWB Electronics

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Hi, May, you're right, absolute polarity (phase) has been discussed for a very long time. It was demonstrated to me by John Curl and Bob Crump with Clark Johnsen, author of the definitive book on the subject of absolute polarity (phase), The Wood Effect, 1988, in attendance at the 2001 CES since the CTC (Curl, Thompson, Crump) Blowtorch preamp just happened to be outfitted with a polarity switch. Since there R no standards for polarity (phase) in the recording or audio industry one is at the mercy of the recording engineer as far as whether a particular CD or LP will be in the same absolute polarity as one's system. Of course one can determine whether his own system is in absolutely polarity using the XLO Test CD or similar test CD wih a track that tests for absolute polarity. There R two solutions to finding whether a particular CD is in correct absolute polarity. Let's define a system that's in absolutely polarity as being one that passes the absolute polarity test tracks on the XLO Test CD, Tracks 12 and 13. If the CD under test sounds bass shy and has a diffuse soundstage it might be out of polarity. If you don't have a polarity switch on the preamp the other way to reverse polarity is reverse the + and - connections on both speakers. Then listen to the CD again. If the system including the CD is now in correct absolute polarity the bass will be lower and of higher quality and the soundstage will be deeper and more coherent. If that's true then the CD is out of absolute polarity. Since there R no standards for polarity, only the ears and motivation of the recording engineer, the odds that a given CD is out of polarity should be rather high, maybe not as high as 50% though. There are reasons why a given system might be have reversed polarity, one reason is that some components invert polarity, another is that + and - connections R incorrect somewhere along the line.

Geoff Kait
Machina Dramatica

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1. Clean all electrical contacts using Caig Deoxit or similar cleaner. Clean all RCA jacks and cable connectors.

2. Clean all electrical contacts of ALL wall outlets in the house, including non audio outlets. The electrical circuits are not isolated electrical so micro arcing at the wall outlet of the refrigerator can show up as noise on the audio circuit. If you don't know know how to clean the electrical contacts on wall outlets hire an electrician to do it.

3. If you have large window(s) in the listening room open them slightly during listening sessions. This will allow some pressure to be dissipated thus eliminating the vibration of the window glass.

4. Remove the steel cover of the circuit breaker box or keep it in the OPEN position for critical listening sessions. Be sure to replace the cover when you're through listening.

Geoff Kait
Machina Dynamica

pentode
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...faster than the electric meter above the fuse box. Retaining the old plug-fuses is the secret to my good sounding stereo; no nasty contact as found in circuit breakers. Also, the 1950's grass wall paper, and painted woodwork, complement the knob & tube wiring in the attic. I understand the lead-based paint on the crown molding is at least as effective as the two, dedicated, 30 & 20 amp stereo circuits.

Hey, thanks. It was fun getting that off my chest. My head does spin with the real number of things one would never think of (or believe) that affects what we hear from our systems. It's fascinating, really, and to think I knew everything when I didn't.

pentode
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...faster than the electric meter above the fuse box. Retaining the old plug-fuses is the secret to my good sounding stereo; no nasty contact as found in circuit breakers. Also, the listening room's 1950's grass wall paper, and painted woodwork, complement the knob & tube wiring in the attic. I understand the lead-based paint on the crown molding is at least as effective as the two, dedicated, 30 & 20 amp stereo circuits feeding the stereo.

Hey, thanks. It was fun getting that off my chest. My head does spin with the real number of things one would never think of (or believe) that affects what we hear from our systems. It's fascinating, really, and to think I knew everything, way back, when I didn't.

pentode
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Sorry for my posting error, above.

Of the many variables in our systems, where does "proper" phase rank with the number of things needed for good sound? Is it now considered enough of a priority that we might start seeing better amplifiers and their remotes with phase switches?

geoffkait
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pentode wrote:

Sorry for my posting error, above.

Of the many variables in our systems, where does "proper" phase rank with the number of things needed for good sound? Is it now considered enough of a priority that we might start seeing better amplifiers and their remotes with phase switches?

I think it's a real issue but I'm not will to invest in a preamp with a polarity switch. I'm not even willing to check the polarity of each CD by switching the positive and negative leads on the back of the speakers (assuming I had speakers) lol The problem is exacerbated by the fact that many CDs are out of polarity so unless you have predetermined their state you don't know whether you're in phase or out of phase. At least one can determine if his system is in or out of absolute polarity quite easily with the help of the XLO Test CD. Some components invert polarity so there's a pretty good chance a given system is out of absolute polarity. The good news is that CDs that are also OOP will sound wonderful on such a system. Lol

Geoff Kait
Machina Dynamica

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Tis the season for giving and I'm not talking about the Free Green Pen I'm offering (with free shipping). I'm talking about more free tips.

1. Obtain absolute level of the CD transport by removing the cover and placing a bubble level directly on the transport spindle or on any surface that is the same level as the spinning CD. Yes, I know it s a lot of problem. But unfortunately the level of the chassis cover is usually not the same level of the transport itself die to tolerance imprecision. If the CD is not spinning perfectly level the disc will tend to wobble and flutter producing jitter. It IS audible, gentle readers.

2. Reduce vibration of the spinning disc by using three 1 1/2 inch strips of black electrical tape laid out on the label side of the CD like spokes of a wheel every 120 degrees.

3. Freeze all light bulbs in the house for 48 hours in the freezer. When you remove the light bulbs place them in the warmer refrigerator portion for about 4 hours after which time put them back knot empty sockets. They don't have to be returned to their original sockets. Wheeeew!

4. Gather all batteries in the house, from all remotes, toys, clocks, you should even put the smartphone in there too since it has a battery. There are also batteries in portable CD players and portable cassette players. Batteries in kids shies that light up when they walk or run. Flashlights, some bicycle flashing lights, Gillette Fusion battery powered razor, Laptop computers, iPods, iPads. Batteries in audiophile battery powered amps, preamps, etc. If anybody can think of anything I missed please let me know.

Geoff Kait
Machina Dynamica
Home of the Free Green Pen

pentode
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RUkidding? Now I thought of one more thing. Why did I bother to respond?

#1 & #2 could have merit, and I'll bite on those, but #3 & #4 smells like fishy bait, and I'm avoiding those hooks.

geoffkait
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pentode wrote:

RUkidding? Now I thought of one more thing. Why did I bother to respond?

#1 & #2 could have merit, and I'll bite on those, but #3 & #4 smells like fishy bait, and I'm avoiding those hooks.

Of course they seem like fish bait. That's what makes them so interesting, No? Don't tell me you only want me to list things that are either easy to explain or that you can figure out with formulae in any high school physics textbook. Besides, these things I mentioned that you think smell like fish bait are rather easy enough to test, no?

There was a quote at the beginning of the new movie The Big Short by Mark Twain,

"The problem is not that there's some information that you don't know, it's that the information you do know and are sure is correct is actually false."

Geoff Kait
Machina Dracula

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