Your Vinyl Transfer Workflow (sharing best needledrop practices)*

Thanks for listening and analyzing my sample. You have to remember I'm slower than the rest of the class. One how does it sound? To me it sound the same as the vinyl and without knowing better I thought is was fine.

As far as the tick you are leaning towards it being caused by mistracking? Someone with a CD might be able to verify. I don't mind leaving them. You would have to really paying strict attention to even hear them.

You guys have been talking a lot recently about stuff being out of phase. I have no idea how to check and how to correct. It may be another Pandora's Box I don't want to open.

 

Here's how I just plainly experiment with settings to denoise the whole file removing only resonance. This is the 2nd pass.

 

Anyone know if this is a tracking issue between 8-9 seconds on the sample the sax sounds bad.
Dropbox - Dave Brubeck.flac - Simplify your life
This shot is the sample you can really see the 20k cut.

 

What is the name of the song? Maybe compare it to one on Youtube.

My Led Zep II has the same ticks at the points you mentioned.

 

That was a great idea it's "Three to get ready". I streamed it and it is baked into the recording. That's the only ugly spot on the whole album.

It's probably the same mastering and that's the best they could get from a 1958 recording.

 

I use YouTube a lot to determine if it's noise or part of the recording.

 

Happy Memorial day fellow needle droppers.

I used amazon prime it's included. It is most likely the latest mastering. What a great sounding album.
The LZ sample just drives home my point about being careful when declicking the whole file. You will loose any ambient noise sounding like a click.
Makes me want to see if click repair will remove it.

 

Phase is talking about either a time delay (given in 360° in relation to the period of waveforms), or the polarity of signals.

There's

• "Phase", where we are talking about a small time difference between stereo channels (tape head misalignment causes this, along with microphone placement);
  
• "Phase", where we are talking about the relationship between frequencies in a signal (electronic filters and and changing frequency response will delay some frequencies more than others);
  
• "Out-of-phase", when one of two stereo channels is wired completely backwards, causing in-air cancellation (you can accidentally do this with speakers);
  
• And finally, "out-of-phase (absolute phase)".

The latter is when both stereo wires are hooked up backwards. Instead of the speaker moving out when it is supposed to, it sucks back in. Some audio components electrically reverse the phase by shortcomings in design.

For you, when you needle-drop, we can make sure that your turntable, preamp, and sound interface all deliver the vinyl's signal in absolute phase by simply observing the waveform when the needle drops.



The needle moving "up" vertically goes (+) in the left channel, but (-) in the right channel. Knowing this, you can also examine dust pops to determine where the piece of grit was in the groove.

When you know it's correct, you can critique either your vinyl's mastering (if you are keen enough to guess how the drum hit should have looked), or poo-poo a later CD remaster made out-of-phase vs the vinyl, as I recently noted.

Differently, when we apply most types of equalizers, highpass filters, etc, we are causing a phase shift, where frequencies around the crossover are delayed. This is rarely audible or discernible, but best to understand and moderate.

 

Thanks well said. Gives me some basic understanding. I have seen a waveform out of balance, not equal above and below 0.0 center line. I never knew how to fix or if it needed fixing. I understand +/- wiring that much is obvious to most people.

 

The picture above is of actually dropping a needle into the groove. As the first blip you see is the needle being pushed up by the tracking force, you observe the left channel goes up but the right channel goes down - the vinyl is being recorded correctly.

Phase otherwise is not something you can easily see in an audio software waveform display, unless you zoom in so you can see individual up and down waves, and compare the timing of them between channels, or are examining using specific test signals (or on classic Audition, pick the "phase" display...)

Instead, you are describing asymmetry in the waveform.

Most acoustic sounds are composed of a sine wave series that have an equal amount of positive and negative signal, and both sum together to make a 0V DC bias. They have the same magnitude of positive and negative-going wave and the peaks lie approximately the same distance from zero.

However, when you have distortion, such as a microphone diaphragm that moves more easily in one direction, or a guitar pedal or other electronics that alter the waveform unevenly, you will see such effects. For example, the distortion mechanism from a guitar pedal:


Artificial synthesized sounds, such as PWM square wave that you might find in a dubstep record, also have more positive than negative content, and will not lie on the center line when viewed.

There's nothing to fix, its just the way the music looks and sounds.

 

Just thought I'd show you something that looks interesting on the spectral display. This is a test record with an 11kHz warble tone "tracking test" that gets louder near the end. The second half is the same segment with a brand new cartridge the same model.



But look above 11kHz? The additional higher lines are 2nd order distortion, 3rd order distortion, 4th order distortion... That's what you are seeing in your "high resolution" needle drop. Distortion. Ultrasonic. Not musical content. Lower frequency tones have less of this pinch-effect distortion.

Also, as the tone gets louder at the end, there's a bit more "spray" I'll call it, noise around the test tone.

And as I write this post, got to wondering if it will look different by transferring slow and speed correcting:


Maybe the top line is lighter...so maybe less distortion overall. hrm.


Also, the phase display of some test tones corrupted by vinyl makes for interesting art...


...

I opened up a brand new cartridge just because I had some niggling ideas about a current project.

Found an anomaly when writing some soon-to-be-shared code to "de-crosstalk" using actual test records - my crosstalk is actually out-of-phase (here we go again!) A left-side tone leaks into the right, backwards. But wait a tick, the right-side tone leaks in-phase. But it's only like that in my brand new cartridge.

So you know what gets written now? Code to correct azimuth, along with code to correct either additive or subtractive crosstalk, and cartridge channel balance (when you've calibrated your phono-in). My cartridge came out to -3% crosstalk (about 25dB); and 8% azimuth correction, corresponding to 4.3 degrees turned clockwise looking from the front (yes, I did the math). Maybe a poor diamond mounting? The results of software correction, though, are startlingly effective.

Also...clean your records. A 16-20kHz inaudible tone made crackling sounds more than silence, until I gave the test record a super wash.

 

If you have access to some fairly recent version of the iZotope Advanced Audio Editor, I for one would like very much to see a comparison of your azimuth correction before and after and an iZotope azimuth correction before and after (on the same source selection, natch). I am a heavy believer in the iZotope stereo channel azimuth and balance corrections when needle-dropping (as well as when I work with digital media), and it would be useful to see some form of rigorous and comparative analysis.

 

Here's a simple setting I arrived at unscientifically to correct a constant "elliptical" 1st-order vertical modulation-limiting mastering EQ (while not excessively boosting sub-bass):

Parametric EQ, side channel:
Fo: 54% of setting (e.g. 80Hz for a 150Hz mastering highpass)
Q: 0.65
Boost: 5.1dB

Red=before:


Then apply your steeper de-rumble.

 

What started as a SoX batch file to do my RIAA speedup EQ and subsonic filtering is now delayed by another revelation...(I'll get that out soon for you to try.)

If I can measure in audio editing software, and correct in processing, an azimuth error - I can also analyze a vinyl test signal, perhaps any arbitrary mono or stereo audio, and find the channel balance, azimuth, and widening correction, modeled on dynamics of misalignment, that results in the least crosstalk.

Feickert Adjust+ software has you make over a half dozen tiny 0.5 degree azimuth tweaks to your tonearm (if you can even do that) and spits out the best sounding one - what if I can tell you the exact amount of error and correction needed with one recording? And let's say your stylus tip, cantilever are all perfectly straight and it is just a misalignment problem inside of the generator...you wouldn't want to skew the diamond line contact; let software reprocessing fix the electrical misalignment...

 

(Putting back my posts that Mr Mod accidentally deleted

The iZotope "azimuth" correction is for tape. It adjusts the inter-channel delay from a tape head misalignment by a fixed amount you input. And level (which you can edit anytime you want)

Audition 3 likewise has automatic phase correction, where it will dynamically process a whole file and provide changing correction. I also use that feature to fix tape head alignment (which also can reach vinyl) but disable the "auto" part and set the delay to a fixed amount since I don't need a program's intelligence.

With cartridge azimuth, instead the stylus is twisted on the tonearm mount and not pointing straight down (or was constructed a bit off), which does not cause any phase or timing issues. Instead, when the 45 degree movement of a groove wall is not aligned perfectly with the cartridge motor, coil, magnets, you get either additive or cancelling signal in the opposite channel. Like crosstalk, but not strictly a narrowing of the sound stage.

The amount due to such an angle can be calculated by geometry. And like level mismatch or an ordinary channel bleed, can be applied to anything you needledrop after the amount is determined.

Vinyl is nearly immune to "phase" issues. Even twisting the cartridge facing inward by 10 degrees will cause less than 1 degree (of 360) phase shift at 10kHz.

 

Unless it is cut into the vinyl...

 

Exactly. The vinyl playback may not introduce phase issues physically but the equipment used to master and cut the vinyl being analog may introduce phase issues. For example, that iZotope Ozone curve I cmae up with to counter Elliptical EQ used in cutting the vinyl simply does not work if I use the same curve with the EQ set to "digital" (which is another name iZotope uses for linear phase). If I set it to analog, it suddenly works quite well. Analog EQ introduces phase differences among frequencies.

Another case where this is evident is if you take a badly brickwalled modern master and apply a 20Hz brickwall highpass filter to it. If you use digital mode, it just removes anything below 20Hz. However, if you switch the EQ to analog mode, in addition to removing the frequencies below 20Hz, it also creates a whole bunch of peaks that seem to be correlated to the music. They're well above 0dBFS but if you reduce the level until they're below 0dBFS, you'd think you've somehow restored the original dynamics of the recording before it was squashed. If you run a DR analysis, the DR number goes up several points. However, it still sounds squashed! Also, if you run a null test, with digital nothing above 20Hz is affected, but with analog, there are a lot of differences going well up into the audible bands. I suspect this is mainly phase related.

 

Thanks. I will try this. I assume this is with SoX ? I haven't used it in years but I'll check it out. I once used the De-emphasis function on SoX applying it to really treble-heavy modern masters and was stunned at how well it improved their listenability.

 

Any software should have a parametric EQ available, but only Ozone uses such stupid names as "bell" "proportional q" and mixes it with other functions in an equalizer hodge-podge. But I guess they give you a mid-side option right there also.

I didn't check the phase response to see how that would cancel or not cancel, but the source's highpass filter will also be a bit shrouded in mystery.

If you do anything in side channel that affects the phase, you're going to have a bad time.

 

iZotope didn't invent those terms. They occur elsewhere as well. It's been my experience that Q values differ from one software EQ to another, even those from the same company sometimes. If you want to go way dwon that rabbit hole, find the thread on here about how to achieve the Sontec EQ curve Steve recommends. It goes on and on and on and never seems to come up with a definitive conclusion.

But that's exactly what the elliptical filter (an analog high-pass filter) to the side channel does, affect the phase in the side channel.

 

(Emphasis mine.)

One note, iZotope determines the inter-channel delay (as it does for inter-channel balance) and supplies a recommended correction, which can be over-written by the user before any correction is applied (same is also true for inter-channel balance). As a further note, iZotope azimuth corrections are determined and specified in sampling-rate "cycles", apparently to the nearest tenth of a sampling cycle. I've seen iZotope specify and azimuth adjust "0.1" cycle of a 192k sample rate. Don't know quite how it determines that, or makes the adjustment (though I can guess), but that's a pretty small time increment. Can it somehow "correct" some effects of cartridge azimuth misalignment? I'll leave that for others to determine.

A further complexity is that for both channel azimuth and channel balance iZotope can work with "adaptive" azimuth alignment and "adaptive" channel balance. Tried it with balance and didn't like it--within a selection adaptive made things dynamic and not fixed. Not good. I haven't tried adaptive with azimuth.

 

No.

"Azimuth" refers to something completely different in vinyl pickup than your software is talking about.

Tape:

There is an inter-channel delay when tape is misaligned and one track crosses the head before the other.



In fact iZotope doesn't offer correction for one of the other dramatic tape misalignment effects: loss of high frequencies, as the magnetic gap detects and blurs a wider area of time on the tape with misalignment:



Vinyl:

Looking from the front, the needle or cartridge (or even the magnets inside) can be mis-aligned. Here we try to get the diamond pointing straight in the groove by setting down on a mirror:


Regardless of such a twist (for which most arms don't have any easy adjustment), the two groove walls pass the stylus at the same time. As the groove is going a mile an hour, and the diamond contact area is incredibly minuscule, and this misalignment doesn't affect the side-to-side contact timing, there is just no opportunity for timing error.

However, tilted counter-clockwise like the above examples, the left channel bleeds over to the right, while the right channel bleeds over to the left inverted. With mono and a counter-clockwise azimuth error, you get more right and less left...and stereo gets even more corrupted. If you could somehow make the twist 45 degrees, mono would be right channel only.



Remixing the channels together in the right proportions of polarity is required to reverse this.

iZotope "azimuth" neither can add nor subtract inverted channel signals together in the correct proportion, nor is phase delay a concern. Adjusting the apparent level imbalance in a mono signal will just worsen things.

No doubt. The tape misalignment isn't going to be changing throughout the recording, but the music will.

One needs a visual representation of phase in software before deciding to correct a tape (or re-align your deck).

 

Just a little "project log"...



On my "good" cartridge with test record, edited down a vinyl "crosstalk test" with test tone left, quiet music right (then reverse).

Scripting a step-through of my chart's "clockwise azimuth" correction increments (phase display):


Stepping through those increments (mid-side pan display):


Can you tell where between 0.5-5.0 degrees the correct azimuth correction is?

Then let's try the "new but bad" cart:


I can also switch stylii to see where the problem follows...

 

You guys are amazing: this is turning into a physics class. Way beyond my level of understanding but interesting nonetheless.
Now if you could turn all this into simple steps in RX8 that make 'drops sound better, that would be lovely.

 

...and it's the stylus provided with the cartridge.





Misaligned to the exact degree predicted by software measurement.

The cantilever and diamond look pretty straight, I'll have to get a few better pictures of the diamond and cantilever before I decide if I want to twist the suspension. Maybe both the cantilever in the suspension and the rubber in the body will rotate to the degrees I want, so this doesn't then become the poster boy for the magic of "software azimuth alignment" fixing an otherwise straight diamond.