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MONO bass - when Mastering For VINYL

When and how to MONO the Bass for vinyl & why you must not believe everything written on websites :)

I see this advice below often repeated - and it makes me annoyed. People that don’t really understand how to cut a great-sounding record - are giving advice to all the other people - who want to believe everything they read. Or the people giving the advice are motivated to make the process EASIER... and not so much about making the process BETTER.

Excerpt from a webpage - describing how to prepare your mix for Vinly mastering.

Lacquer Mastering requires very specific audio standards. Following this guide will ensure your audio will uphold its quality during the transfer to an analog master
All Bass Frequencies should be centered (below 150 Hz). Phase issues in the bass frequencies can cause a collapse of the groove, causing a skip.

This is patently wrong - all of it. And this advice is repeated everywhere.

The bottom line is, this advice, if taken exactly as it’s stated - WILL make it easier and faster to cut a typical LP side. But at the same time - this filtering is RUINING YOUR MIX! - read on. ..

This is how the advice should read.

In some cases - when extreme bass frequency panning is used - The disk cutting engineer may be forced to partially mono the bass. This should ONLY be used when absolutely necessary to prevent the groove from becoming so narrow that it can not be traced by the playback styli. Please, Never, Mono the bass of your recording for vinyl - unless you have been told that it is required by the engineer cutting Your Record. Mono-ing the bass sounds like it’s harmless - but it removes VITAL low and low-midrange information that can turn a world-class guitar sound into a cheap boring - flat - underpowered - transistor type of guitar sound. And don’t get me started regarding piano records.

Always consult your cutting engineer before taking corrective measures for vinyl. My experience has shown that often - the mix engineer will overcompensate for the bass issues on vinyl.

Vinyl is very capable of reproducing gobs of bass - and some out-of-phase bass is not a problem for a skilled cutter For optimum results, this processing really must be left for the cutting engineer to implement.

Most mixing studios do not have the proper tools or experience to apply the correct amount of bass mono-ing. They can not look at the groove to see what is happening.

The Duration conundrum…

When A record side is long - we must lower the level so that the extra grooves fit. Reducing the level often eliminates the issue of bass and phase management. A “stereo” bass record might be a problem if it's part of a 12-minute LP side, but that same stereo bass would cut perfectly on a 22-minute side. The cutting level has to be considered when making these destructive modifications.

But it gets even more complicated. There are times when bass monoing is used to help Increase the cutting level. When the producer wants the record to be loud - and is not as concerned about the bass. And then even rare situations where applying subtle bass mono-ing actually improves the sound of the mix.

Don't fall for the general catch-all advice.

The bottom line is - these are not set-and-forget adjustments - but that is exactly how low-cost - and factory lathe operators work. They are told that no one can hear the bass mono-ing and so they leave the filters in by default.

Absolutely the same advice applies to high-frequency vocal essess… On a long side the cutting level will be lower - and there is much less risk of sibilant playback distortion. But on a short side - where the cutting level can be increased … those esses can turn ugly.

GREAT sounding mixes - can sound great on vinyl - if they are not destroyed by bad internet advice.

Stop destroying your mixes - Send them to a cutting ENGINEER - who will use the technology to create the best possible sonic solution. Masterdisk is one of your options. We cut records for every pressing plant in the world, so don’t let someone mislead you into thinking that you have to put up with “ boring, soft, bass-neutered " records.

AND! IF you plan on sending your mixes off to a cheap and fast disk replication service - broker - or factory, those disk cutters usually leave the low-end filters and high-frequency filters in all the time !!!! So if you mono your bass and roll off the top end - your record will be double processed.

This is the number 1 reason why a lot of today's vinyl sounds Boring!

Check to see where your favorite records were cut.

Records made at Masterdisk - always have the Masterdisk stamp in the deadwax.

Scott Hull

Chief Engineer / Owner

Masterdisk Studios - NY

Mastering and Cutting Vinyl Records Since 1973


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