Unbalanced L&R on WAV (Vinyl Master)

[Hypagen]

Do the L&R channels on a WAV (mastered to cut a 12" vinyl) need to be EQ'd differently to translate properly, i.e. the left channel needs to have a duller sound and less volume than the right.

After listening to the unmastered track which sounded well balanced with good stereo imaging, I've just listened to the mastered WAV and the left channel sounds dull which is throwing off the stereo image. It also 'looks' at a lower average volume (compared to the right channel) although it's peaking the same on my VU meters. I did a spectrum analysis of the file and the left channel has 2 dips centered around 1200hz and 2700hz with about 5dB reduction each. The right channel hasn't had these EQ adjustments made and sounds fine.

Any thoughts would be greatly appreciated.

[Paul Gold]

Originally Posted by Hypagen

Do the L&R channels on a WAV (mastered to cut a 12" vinyl) need to be EQ'd differently to translate properly, i.e. the left channel needs to have a duller sound and less volume than the right.

No. Vinyl likes mono and this is creating stereo.

the left channel has 2 dips centered around 1200hz and 2700hz with about 5dB reduction each. The right channel hasn't had these EQ adjustments made and sounds fine.

Any thoughts would be greatly appreciated.

This is odd and seems like a mistake, unless there was some panned element in the original mix like a high hat that was severely out of whack.

[bgrotto]

I thought records were cut using M/S, not L/R? Am I making things up?

[Cellotron]

Originally Posted by bgrotto

I thought records were cut using M/S, not L/R? Am I making things up?

The signal sent to the cutter head is in fact L/R. But Mid channel (mono) energy is cut as lateral (horizontal) motion - while Side channel energy of this L/R pair are cut into the lacquer as vertical motion.

A really good visual illustration of all this that easily clears up what is confusing as written above is at -
How to pack a stereo signal in one record groove

Best regards,
Steve Berson

[Cellotron]

Originally Posted by Hypagen

Do the L&R channels on a WAV (mastered to cut a 12" vinyl) need to be EQ'd differently to translate properly, i.e. the left channel needs to have a duller sound and less volume than the right.

No - they don't - and as Paul noted it's best if the channels are mono compatible as much as possible (especially in the lower frequencies if you are wanting to cut at hot as possible levels).

After listening to the pre-master which sounded well balanced with good stereo imaging, I've just listened to the mastered WAV and the left channel sounds dull which is throwing off the stereo image. It also 'looks' at a lower average volume (compared to the right channel) although it's peaking the same on my VU meters. I did a spectrum analysis of the file and the left channel has 2 dips centered around 1200hz and 2700hz with about 5dB reduction each. The right channel hasn't had these EQ adjustments made and sounds fine.

Any thoughts would be greatly appreciated.

What things "look" like with digital analyzers doesn't matter for a hill of beans compared to what they sound like on a test cut. Mix to where you want things to sound - and then get a reference acetate or DMM for your approval made prior to having masters cut, plates made and test records pressed. It saves a lot of hassle and guessing.

Best regards,
Steve Berson

[Hypagen]

Originally Posted by Cellotron

What things "look" like with digital analyzers doesn't matter for a hill of beans compared to what they sound like on a test cut.

Best regards,
Steve Berson

That's what I thought.

Thanks for everyones input, but what about the EQ adjustments in one channel? Listening to the pre-master (in my opinion) there was no need for this.

My conclusion was that maybe the needle follows the leading edge of the groove (thus one side experiences extra pressure) and an EQ adjustment needs to be made to counteract this and provide an equal balance?

[bgrotto]

Originally Posted by Cellotron

The signal sent to the cutter head is in fact L/R. But Mid channel (mono) energy is cut as lateral (horizontal) motion - while Side channel energy of this L/R pair are cut into the lacquer as vertical motion.

A really good visual illustration of all this that easily clears up what is confusing as written above is at -
How to pack a stereo signal in one record groove

Best regards,
Steve Berson

Thanks for the link. Unfortunately, I couldn't seem to wrap my head around it...

So lemme ask in the simplest/clearest-for-me-to-comprehend way I know how:

Does the stylus on a turntable read "left and right" or "mid and side"?

Thanks again!

[narcoman]

Originally Posted by Hypagen

That's what I thought.

Thanks for everyones input, but what about the EQ adjustments in one channel? Listening to the pre-master (in my opinion) there was no need for this.

My conclusion was that maybe the needle follows the leading edge of the groove (thus one side experiences extra pressure) and an EQ adjustment needs to be made to counteract this and provide an equal balance?

please - not pre-master.....

I've taken CD copies of vinyl cuts home for ruff reference - never had what you described.

[fader8]

Originally Posted by Hypagen

My conclusion was that maybe the needle follows the leading edge of the groove (thus one side experiences extra pressure) and an EQ adjustment needs to be made to counteract this and provide an equal balance?

No, the turntable itself takes care of this. Most have an adjustment available to counteract this force. The RIAA de-emphasis EQ is identical in both channels.

Originally Posted by bgrotto

So lemme ask in the simplest/clearest-for-me-to-comprehend way I know how:

Does the stylus on a turntable read "left and right" or "mid and side"?

You can think of it as the stylus itself works with a mid and a side signal mechanically. But what is output from the cartridge coils is discrete stereo.

Maybe this helps: If you record a sine wave and both channels are matched in level and polarity, in phase, then the stylus will move side to side. If the 2 channels are out of phase, then the stylus will move up and down. The cartridge windings are a form of MS decoder you might say, so what you get out is separate channels.

[bgrotto]

Originally Posted by fader8

Maybe this helps: If you record a sine wave and both channels are matched in level and polarity, in phase, then the stylus will move side to side. If the 2 channels are out of phase, then the stylus will move up and down. The cartridge windings are a form of MS decoder you might say, so what you get out is separate channels.

Brilliant! Excellent explanation! Thanks

[Hypagen]

Originally Posted by narcoman

please - not pre-master.....

I've taken CD copies of vinyl cuts home for ruff reference - never had what you described.

Sorry - unmastered?

[Hypagen]

Originally Posted by Paul Gold

This is odd and seems like a mistake, unless there was some panned element in the original mix like a high hat that was severely out of whack.

I thought it seemed very odd too as the unmastered track sounded fine.