DR, Brickwalling, Fidelity, and Perceived Loudness

[MidiMagic]

I used , years ago , to have a Transcriptor Hydraulic Reference Turntable , which worked on the principle of isolating the record from the platter by supporting it on six tiny soft rubber points : issues such as surface noise and pre/post echo were much more noticeable on that turntable than with other designs ( despite it being a beautiful piece of craftsmanship and a lovely thing to behold ) .

I see absolutely no way to correlate record support with pre-echo, post-echo or surface noise. The causes of these have nothing to do with how the record is supported.

I tried many turntables , from Garrard , Thorens , Dual , Technics , Linn , Rega , Yamaha , Aristin , Fons , and anything potentially good that came through the shop , before buying my Michell Gyrodec , and adding the QC power supply some years later . I could upgrade to the Orbe platter for even more mass but have yet to do so . Even old records which sounded noisy in the past do sound quieter on the Gyrodec .

If they sound quieter on the Gyrodec, I would say that the listening conditions are different (phono EQ or room response). Another possibility is a resonance in the pickup arm.

 

[jimfisheye]

Well , I think it does : the energy imparted into a record by the stylus will be proportionately of greater significance the less massive the record is , all other things being equal .

Pretty sure not unless approaching the speed of light.

 

[JulesRules]

That is 'print-through' from the analogue tape that the LP was mastered from - not an issue from the vinyl itself.

Thank you sir. I don't listen to LPs but one CD release where I noticed it was the 2006 deluxe edition of Tears for Fears' Songs from the Big Chair (the intro of "Everybody Wants to Rule the World" appears quietly at the end of "The Working Hour"). Interestingly, the 2014 remaster doesn't have it.

 

[Stephen W Tayler]

Thank you sir. I don't listen to LPs but one CD release where I noticed it was the 2006 deluxe edition of Tears for Fears' Songs from the Big Chair (the intro of "Everybody Wants to Rule the World" appears quietly at the end of "The Working Hour"). Interestingly, the 2014 remaster doesn't have it.

Yes, this is fairly common. A lot of CDs - especially in the early days - were frequently made from tapes called 'Production Copies'

Quite often back in the days of mostly cutting records the mastering techniques had to be enacted in real time - switching and altering EQ and compression and level changes from track to track - quite a performance to get it right in one pass. Because LPs could only be pressed from a stamper for a limited period before it wore out, the lacquer would have to be cut again. So frequently when the original mastering was being done - a tape copy with all the changes was made. Frequently these were also made to send out to multiple pressing plants around the world.

These copies were often made at 15ips quarter inch with no noise reduction, so were much more vulnerable to print through - particularly if they were used some time after being made.

I have heard some of the projects that I was involved with that were originally mixed to half inch 30 ips with Dolby SR, so there was no printhrough at all - and the LPs cut from those tapes were very clean.

But then several times when I heard the so called 'remastered' CDs - there was audible print through so these had to be derived from production copies - NOT the original mix tapes.

Things are handled much better these days - but as I am working with so many vintage recordings, stereo and multitrack, that have been digitised from original analog tape, you would not believe the amount of print-through - quite often several decades later!!!

SWT

 

[MidiMagic]

Yes, this is fairly common. A lot of CDs - especially in the early days - were frequently made from tapes called 'Production Copies'

Quite often back in the days of mostly cutting records the mastering techniques had to be enacted in real time - switching and altering EQ and compression and level changes from track to track - quite a performance to get it right in one pass. Because LPs could only be pressed from a stamper for a limited period before it wore out, the lacquer would have to be cut again. So frequently when the original mastering was being done - a tape copy with all the changes was made. Frequently these were also made to send out to multiple pressing plants around the world.

If they planned ahead, they would never have to cut more than one lacquer per side.

1. They cut the lacquer. They make two (one for each side of the record).

2. They electroplate the metal master from the lacquer. This destroys the lacquer. The master had ridges instead of grooves.

3. They electroplate a metal mother from the metal master. The mother has grooves. They can make as many mothers as they want from the metal master. They can also save the metal master to make more mothers later.

4. They electroplate a metal stamper from the metal mother. The stamper has ridges. They can make as many stampers as they want from the metal mother. They can also save the metal mother to make more stampers later.

5. They put two stampers (one for each side) into the record press. The press is used to press records. The records have grooves. The stampers wear out and must be replaced.

Only if they cheap out do they make one stamper from the lacquer.

 

[marcb]

If they planned ahead, they would never have to cut more than one lacquer per side.

1. They cut the lacquer. They make two (one for each side of the record).

2. They electroplate the metal master from the lacquer. This destroys the lacquer. The master had ridges instead of grooves.

3. They electroplate a metal mother from the metal master. The mother has grooves. They can make as many mothers as they want from the metal master. They can also save the metal master to make more mothers later.

4. They electroplate a metal stamper from the metal mother. The stamper has ridges. They can make as many stampers as they want from the metal mother. They can also save the metal mother to make more stampers later.

5. They put two stampers (one for each side) into the record press. The press is used to press records. The records have grooves. The stampers wear out and must be replaced.

Only if they cheap out do they make one stamper from the lacquer.

Ok, he erroneously said stampers rather than mothers. But otherwise the point remains.

LP production in the 70s - particularly in the US - was assembly-line, often at several plants geographically disperses across the continent. The question became whether it’s easier and cheaper to keep the old, original metal and make new mothers centrally from that every time the mothers wore out or were damaged - or just cut a new lacquer locally from a copy of the eq’d, compressed, whatever, etc. production master tape.

 

[Stephen W Tayler]

All of this information just shows that things may have not been very forward looking in the past, and a lot of corners were cut, sadly.

These days there is a lot more emphasis on archiving and restoration, which is a good thing.

 

[par4ken]

After much searching I came upon a VST plugin that restores dynamic range to clipped audio (Relife and Relife x64). It has successfully been used by some to restore brickwalled audio! I don't claim that it can completely restore a badly brickwalled recording (once the damage is done it's doubtful that it can be fully repaired). I've just started to experiment with it. It does restore dynamic range but of those selections that I've experimented with so far there still was a grittiness to the sound quality. There are three peak restore algorithms, so it might take experimentation to find the one that works the best.

For a minimum donation of €17.50 to Terry West Productions you can download as many of his plugins as you want! Terry West Productions - x64 Plugins

 

[marcb]

All of this information just shows that things may have not been very forward looking in the past, and a lot of corners were cut, sadly.

These days there is a lot more emphasis on archiving and restoration, which is a good thing.

It was just product. Sure there was some level of care for the initial release, but for a re-pressing 4 or 5 years after release? The vast, vast majority of record buyers didn't even notice (then or now).

Hell, in the mid-70s, we were only 20 years removed from Elvis on Sun Records. Nobody was thinking a bunch of nerds (a term which was just then becoming popularized...) would be worried about the details and nuance of re-pressings and production masters of record albums 50 years later - let alone discussing them with people all over the world on something called message boards on a thing called the internet.

 

[kfbkfb]

A lot of CDs - especially in the early days - were frequently made from tapes called 'Production Copies'

My 1st CD purchase 39 years ago this month was the Billy Joel/Nylon Curtain album made in Japan by Sony for CBS. This CD version was accused of having somewhat poor sound quality since it was allegedly made from a tape prepared for prerecorded compact cassette production.

I bought the (USA) Columbia prerecorded cassette version just to hear the album since I didn't get a CD player until 1984-11, but I only had a mid-fi cassette deck so it wasn't possible to accurately compare the cassette and CD sound quality.


Kirk Bayne

 

[Dynamic Editor]

After much searching I came upon a VST plugin that restores dynamic range to clipped audio (Relife and Relife x64). It has successfully been used by some to restore brickwalled audio! I don't claim that it can completely restore a badly brickwalled recording (once the damage is done it's doubtful that it can be fully repaired). I've just started to experiment with it. It does restore dynamic range but of those selections that I've experimented with so far there still was a grittiness to the sound quality. There are three peak restore algorithms, so it might take experimentation to find the one that works the best.

For a minimum donation of €17.50 to Terry West Productions you can download as many of his plugins as you want! Terry West Productions - x64 Plugins

I swear up and down about how good this one VST plugin I've been using for years called "Perfect Declipper". It both takes the compressed sections and makes them more dynamic as well as pretty much eliminates the crackly distortion caused by loud mastering!

Here are some examples of what I was able to do with the program:

• "Little Cream Soda" by The White Stripes (Original/Edit)
• "Ceiling Unlimited" (Original Mix) by Rush (Original/Edit)
• "Nod Your Head" by Paul McCartney (Original/Edit)
• "Easily" by Red Hot Chili Peppers (Original/Edit)
• "My Big Mouth" by Oasis (Original/Edit)

I've been posting my edits using the plugin for quite a while and I'm shocked the plugin hasn't got more traction.

 

[JulesRules]

It both takes the compressed sections and makes them more dynamic

Probably that's the problem. I'm just listening to the title track of the Muse album and I recognize the sound of the declipper assuming how the drum hits should sound. It doesn't really sound like a drum, unfortunately.

I've been messing around with similar stuff myself, trying to make Clockwork Angels more listenable, but I'm not really all that convinced. Checked out another track I'm rather familiar with ("Only Mama Knows" by Macca) and you just can't undo the way the instruments are all smashed together.

Admittedly I'm just listening to bits and bobs here and there, and I'd have to compare these tracks directly to the originals with levels matched...

 

[Dynamic Editor]

Probably that's the problem. I'm just listening to the title track of the Muse album and I recognize the sound of the declipper assuming how the drum hits should sound. It doesn't really sound like a drum, unfortunately.

I've been messing around with similar stuff myself, trying to make Clockwork Angels more listenable, but I'm not really all that convinced. Checked out another track I'm rather familiar with ("Only Mama Knows" by Macca) and you just can't undo the way the instruments are all smashed together.

Admittedly I'm just listening to bits and bobs here and there, and I'd have to compare these tracks directly to the originals with levels matched...

Yeah, it can only "undo" certain types of dynamic range compression. I do definitely think it can do a great job at pretty much removing that distortion, though. Not sure what happened with that Paul McCartney album, though. It's one of the loudest-seeming albums I own, maybe because of how the vocals are mixed.

And what Muse song?

 

[JulesRules]

And what Muse song?

"Will Of The People" - I knew that was a mess, so I was curious to hear how it compared. (The vinyl seems to be better, although I know you can't really compare DR readings of vinyl and digital. But this rip at least doesn't sound half bad.)

 

[par4ken]

I know you can't really compare DR readings of vinyl and digital. But this rip at least doesn't sound half bad.)

Why not? Obviously a dirty scratchy vinyl rip will have a higher DR value but a good clean (cleaned up) copy will produce a DR value similar to a non-brickwalled digital copy. I check the DR value of all my vinyl rips and while they vary a lot, most commonly they produce a DR value of 12. Good digital copies produce similar DR values.

 

[Dynamic Editor]

"Will Of The People" - I knew that was a mess, so I was curious to hear how it compared. (The vinyl seems to be better, although I know you can't really compare DR readings of vinyl and digital. But this rip at least doesn't sound half bad.)

How does this edit of mine sound?

 

[JulesRules]

Why not? Obviously a dirty scratchy vinyl rip will have a higher DR value but a good clean (cleaned up) copy will produce a DR value similar to a non-brickwalled digital copy. I check the DR value of all my vinyl rips and while they vary a lot, most commonly they produce a DR value of 12. Good digital copies produce similar DR values.

The problem is that there are more stages involved, you're recording the playback and then analysing that. If you're recording the output of a CD and then analysing that file, it will not have the same DR as the original digital file. Somebody once said it's like running it through an all-pass filter.

 

[par4ken]

The problem is that there are more stages involved, you're recording the playback and then analysing that. If you're recording the output of a CD and then analysing that file, it will not have the same DR as the original digital file. Somebody once said it's like running it through an all-pass filter.

It would take an awful lot of filtering to alter the DR value. Sorry but I don't understand the point that you are making. DR value is a measure of the average difference in level, low level to high. Brickwalling flattens the level, so the less variation the lower the DR value. Extra A/D and D/A conversions should not change the DR value.

The vinyl that I have digitised myself usually show DR values of 9 to 16, with 12 being by far the most common. LP's always sound good. I'm a believer in DR readings as every CD that I have ever thought didn't sound right proved to have a very low DR value.

I would open the offending CD in an audio editing program and immediately see the brickwalling. That was before I took stock of DR readings at all, but since have found that the DR value and sound quality are closely linked. The brickwalled CDs all had a low DR value. Audiophile CD's usually run about a 12, the same as the vinyl.

What angers me most about this is that with the introduction of the CD we were promised greater dynamic range than what we were getting with vinyl. Instead we get less in the name of loudness, or to appease the smartphone user!

 

[DuncanS]

Somebody once said it's like running it through an all-pass filter.

An All-pass filter just introduces phase-shift/delay

 

[MidiMagic]

It would take an awful lot of filtering to alter the DR value. Sorry but I don't understand the point that you are making. DR value is a measure of the average difference in level, low level to high. Brickwalling flattens the level, so the less variation the lower the DR value. Extra A/D and D/A conversions should not change the DR value.

The vinyl that I have digitised myself usually show DR values of 9 to 16, with 12 being by far the most common. LP's always sound good. I'm a believer in DR readings as every CD that I have ever thought didn't sound right proved to have a very low DR value.

I would open the offending CD in an audio editing program and immediately see the brickwalling. That was before I took stock of DR readings at all, but since have found that the DR value and sound quality are closely linked. The brickwalled CDs all had a low DR value. Audiophile CD's usually run about a 12, the same as the vinyl.

What angers me most about this is that with the introduction of the CD we were promised greater dynamic range than what we were getting with vinyl. Instead we get less in the name of loudness, or to appease the smartphone user!

Actually, it is to get louder play on the radio. They think that sells more CDs.