Question about Immigrant Song's Master Recording

[peter77]

Hello, It seems to me that with each better pair of headphones I buy, more expensive DAC/Amps that I acquire, and better music source that I find, I am only then able to open up Immigrant Song to sound only slightly better? Is it me or does Immigrant Song sound distant, soft and clouded in its master mix? In particular, what is that noise in the first two seconds of the song that sounds like static? Was Immigrant Song's master copy not properly recorded with great equipiment or is it just me being picky? Thanks in advance for your time.

 

 

[Zep Hed]

Think it's studio hiss at the very start.

[SteveZ98]

2 hours ago, Zep Hed said:

Think it's studio hiss at the very start.

According to Wikipedia, which references a book about Zep's songs by Dave Lewis, "the hiss is feedback from an echo unit."

https://en.wikipedia.org/wiki/Immigrant_Song

Regarding the sound quality of the song, the latest version I have is from the Deluxe edition of the third album. To me, it sounds as good as the rest of the songs on that album. There's an intentional echo/watery quality to the guitar in places that's unusual, but otherwise it sounds similar to the rest of the disc. 

[Strider]

1 hour ago, SteveZ98 said:

According to Wikipedia, which references a book about Zep's songs by Dave Lewis, "the hiss is feedback from an echo unit."

https://en.wikipedia.org/wiki/Immigrant_Song

Regarding the sound quality of the song, the latest version I have is from the Deluxe edition of the third album. To me, it sounds as good as the rest of the songs on that album. There's an intentional echo/watery quality to the guitar in places that's unusual, but otherwise it sounds similar to the rest of the disc. 

I have no problem with the sound of the song or the rest of the album, either. It doesn't sound cloudy or muddy to me. That goes for whether I am playing my original vinyl or the deluxe remastered vinyl and cd.

Remember, Jimmy Page's aim for Led Zeppelin III was to purposely not make a sequel to Led Zeppelin II. They were determined to branch out and not just regurgitate endless variations of "Whole Lotta Love".

That entailed new approaches to songwriting and new approaches to guitar tones and scales used in recording Led Zeppelin III. You'll notice there is none of the "Les Paul thru a Marshall stack" monster sound that Led Zeppelin II had on tracks like "Whole Lotta Love", "Lemon Song", "Heartbreaker", "Bring It On Home".

They wanted an album that was the opposite of Led Zeppelin II and Led Zeppelin III achieved that aim.

Edited October 9, 2020 by Strider

[sixpense]

Compare the final version against the companion version and Jimmy definitely added a bit of effects (purposely) to the track.

To me, the tracks that have issues with tape hiss are The Ocean and Dancing Days. If you have the companion version of Dancing Days on vinyl, give it a listen. The differences are dramatic.

Also, listen to the companion version of For Your Life and you will be able to hear all the bass triplets Bonzo is playing that can't hear on the final version. 

[peter77]

On 10/9/2020 at 12:06 AM, peter77 said:

Hello, It seems to me that with each better pair of headphones I buy, more expensive DAC/Amps that I acquire, and better music source that I find, I am only then able to open up Immigrant Song to sound only https://snaptube.cam/https://9apps.cam/ slightly better? Is it me or does Immigrant Song sound distant, soft and clouded in its master mix? In particular, what is that noise in the first two seconds of the song that sounds like static? Was Immigrant Song's master copy not properly recorded with great equipiment or is it just me being picky? Thanks in advance for your time.

 

 

A lot(Most?) of LZ's recordings don't sound very pristine. Especially if you compare them to other contemporaries like The Who and Pink Floyd. I think they did a lot of hasty/off the cuff recordings.

 

[mrlowry]

Keep in mind that with analog tape every time you overdub something you get an additional layer of tape hiss.  Since many times Jimmy Page had multiple layers of  the same guitar part or multiple guitar parts at the same time the overall background noise of nearly song that they recorded in the studio was going to be higher.   To my ears the worst offender is "Celebration Day" which sounds pretty murky and muddy, luckily it suits the song in a cool way because it adds a touch of mystery.

Another potential issue is that many of the albums were recorded with mobile studios in unconventional locations as apposed to a standard studio.  

Noise reduction on tape eventually partially overcame the overdub/tape hiss issue which is why Presence, which probably has the most overdubs still sounds pretty clean.     

[woz70]

On 10/13/2020 at 4:25 PM, mrlowry said:

Keep in mind that with analog tape every time you overdub something you get an additional layer of tape hiss.  

No you don't..... Unless you do it like The Beatles had to. 

Most of their output was recorded on 4-track tape. If you filled the four tracks up and wanted to overdub some more you had to do a submix (or a bounce) to a second tape machine - hence adding a second generation of tape hiss. 

For example :

Track 1: drums

Track2: bass

Track3: guitar

Track4: vocal

 

You want to add some backing vocals and a tambourine... But you've run out of tracks. So you could send a mixed signal (sometimes called a stem) of drums, bass and guitar to track 1 on a second tape machine, and the vocals to track 2, leaving you tracks 3 and 4 to record Backing vocals and tambourine, like this:

 

Track 1: mixed drums, bass and guitar

Track 2: vocal

Track 3: backing vocal

Track 4: tambourine

The techs at Abbey Road were truly excellent at their job, so generational noise was kept at a minimum, but The Beatles went too far with some songs. As an example you can really hear the generational noise building up towards the end of 'She's So Heavy'. 

 

Most of Zeppelin's output was recorded on 8 track tape. With careful planning there is no need for bouncing 2 or more tracks onto 1, so no need whatsoever to add generational tape noise.... Until you mix the track and record it to a stereo master tape. 

(So... Even the best quality analogue master tapes are 2nd generation... before they even get sent to be ‘Mastered’ which is a third generation of tape hiss!  This is why some people liked (and still like to) master directly to acetate. Jack White is one of the modern proponents of this technique).

A typical zep multitrack might look like this:

Track 1 & 2: drums

Track 3: bass

Track 4: guitar

Track 5: guitar overdub 1

Track 6: vocal

Track 7: backing vocal

Track 8: guitar overdub 2 and solo

No need to bounce, no need to add generational tape hiss. 

The only other noise that will be added during initial recording, or overdubs, is hiss and hum from Amps, electrical (Johnson) noise added by compressors and other effects, the path of the signal through the desk and the tape machines' electronics, and eventual loss of high frequency response of you play the tape back too many times or do too many takes an overdub (this is why Sly and the family stone's recordings are so muffled sounding) 

By the time they got to Presence I think they were on 16 track tape, and ITTOD was probably 24 tracks... So ample room for recorded sources without having to resort to bouncing tracks and adding noise. 

Edited October 17, 2020 by woz70

[mrlowry]

On 10/17/2020 at 5:30 PM, woz70 said:

A typical zep multitrack might look like this:

Track 1 & 2: drums

Track 3: bass

Track 4: guitar

Track 5: guitar overdub 1

Track 6: vocal

Track 7: backing vocal

Track 8: guitar overdub 2 and solo

No need to bounce, no need to add generational tape hiss. 

The only other noise that will be added during initial recording, or overdubs, is hiss and hum from Amps, electrical (Johnson) noise added by compressors and other effects, the path of the signal through the desk and the tape machines' electronics, and eventual loss of high frequency response of you play the tape back too many times or do too many takes an overdub (this is why Sly and the family stone's recordings are so muffled sounding) 

By the time they got to Presence I think they were on 16 track tape, and ITTOD was probably 24 tracks... So ample room for recorded sources without having to resort to bouncing tracks and adding noise. 

Some of this is correct but it's too much of a simplification.  Firstly; and most importantly many times Jimmy Page has 4 or 5 layers of guitars playing the same part to give it that thick and heavy sound.  For an example if you listen very closely to Black Dog it has one guitar part but  that one part is made up of multiple layers of different performances of that one guitar part (probably 5 layers.)  You can hear this same approach but with less guitars on "In My Time of Dying" where two different guitars play the same part.  One has a fuzzier tone and one has a cleaner tone.  Listen to it on headphones, which makes it easier to hear them.

Secondly, many times Jimmy Page would have a guitar-army arrangement with many guitar parts going on at the same and because he was only one person he had to overdub them. Songs like "Celebration Day", "Trampled Under Foot", "Dancing Days",  "Ten Years Gone", and "Achilles Last Stand" are all great examples.  The first four start to sound a bit muddy because of the multiple guitar parts and layers of tape hiss.  By the time "Achilles" comes around apparently tape noise reduction got good enough were it wasn't as much of a problem  That's why Presence is probably their cleanest sounding album.   

With analog there are two things to worry about.  The first is generation loss which is when you copy one tape to another tape when bouncing down multiple tracks to one track to free up recording space, as described by the post above.  The second is the loss that occurs every time a piece of analog tape runs through a machine a little bit of the magnetic material is worn off in the process.  Queen faced this problem when recording "Bohemian Rhapsody."  They even joked about being able to see through the tape by the end of the recording session.  Fleetwood Mac (with Rumors) and Pink Floyd (with The Wall) tried to address the issue of tape wear by recording the rhythm tracks on a tape then copied that tape to work on.  After all of the other work was done they then went back to the pristine rhythm track tapes to finish the work by bring in the overdubs at that point so the basic rhythm track tape didn't have to go through the machine over, and over, and over, and over again.  For the Fleetwood Mac Rumors sessions they discuss that work flow extensively on the Classic Albums documentary that covers it.  It's a good DVD if you haven't seen it.  To my knowledge Jimmy Page never used this pristine rhythm track method with Led Zeppelin, probably because it would have slowed down the recording process and disrupted his creativity too much.   

Edited October 19, 2020 by mrlowry
Cleaned up grammar

[woz70]

8 hours ago, mrlowry said:

Some of this is correct but it's too much of a simplification. 

Not an oversimplification at all.  

As a real-world example, here's the actual track setup for Ramble On (the tracks might not be in the order the are on the original multitrack tape, but they are (copies of) the original multi's and it's how I've got them arranged in my studio):

Track 1: Acoustic guitar
Track 2: Bass (Judging by the spill that can be heard it was recorded simultaneously with Drums and acoustic guitar)
Track 3: Drums L
Track 4: Drums R
Track 5: Electric guitar - obviously recorded as an overdub, but it was recorded on a pristine empty track, so only first gen. tape hiss - same as the Bass, Drums and Acoustic Guitar.  Adding this overdub has not added any more tape hiss than was already there, and the same goes for the following overdubs:-
Track 6: Guitar overdub - twinkly guitar but in the pre-chorus, plus one part of the harmony guitar solo - again an obvious overdub (it says so on the track sheet), again recorded on a pristine track so, again, only 1st gen. tape hiss.
Track 7: Vocal - very obviously not recorded at the same time the rest of the band were tracking (the spill you can hear contains acoustic guitar, electric guitar and harmony solo), so an overdub.  Again, only 1st gen. tape hiss.
Track 8: Vocal doing a double of 'Ramble On' for the chorus, plus second part of harmony guitar solo.  Again an overdub, but only 1st gen. tape hiss.

So in this song:
1: no need to bounce any tracks to another and add generational noise;
2: only first generation hiss on EVERY TRACK;
3: only 8 tracks available; and there are still points with four guitars playing simultaneously, thanks to good planning of what each track would be used for.

Just to reiterate: overdubbing on a pristine track will not add any more tape hiss than is already there.

So that covers:

8 hours ago, mrlowry said:

Firstly; and most importantly many times Jimmy Page has 4 or 5 layers of guitars playing the same part to give it that thick and heavy sound. 

Next point:

8 hours ago, mrlowry said:

For an example if you listen very closely to Black Dog it has one guitar part but  that one part is made up of multiple layers of different performances of that one guitar part (probably 5 layers.) 

No. Black Dog has 3 quite distinct guitar parts in all.  One panned hard left, one panned hard right, and finally the solo.  The 'thick' sound is all down to how it was recorded, and how the mixing engineer dealt with processing those tracks during mixdown.  Lots of people (you, and a few people I have worked with amongst them) seem to think that you fatten up a guitar sound by recording multiple stacked version of the same part.  Weirdly that can actually make a track sound thinner, and usually two versions of the same part recorded with different amps/guitars and panned apart sounds much fatter than 5 guitars playing the same thing - which, depending on the guitarist can often end up sounding like a right mess.

8 hours ago, mrlowry said:

Listen to it on headphones, which makes it easier to hear them.

I have done, for over 40 years.

8 hours ago, mrlowry said:

Secondly, many times Jimmy Page would have a guitar-army arrangement with many guitar parts going on at the same and because he was only one person he had to overdub them. Songs like "Celebration Day", "Trampled Under Foot", "Dancing Days",  "Ten Years Gone", and "Achilles Last Stand" are all great examples.  The first four start to sound a bit muddy because of the multiple guitar parts and layers of tape hiss.  By the time "Achilles" comes around apparently tape noise reduction got good enough were it wasn't as much of a problem  That's why Presence is probably their cleanest sounding album.

I've covered this above - overdubbing does NOT (necessarily) mean more hiss.  The apparent 'muddiness' is not down to fidelity, it's down to eq choice during tracking and at mixdown, which means that's exactly how Mr. Page wanted it to sound.

"Celebration Day" is definitely complex, but there are only ever 3 guitars playing at once, usually panned hard Left and Right, sometimes one in the middle too.  You're probably going to say 'but the guitar solo is surely two guitars - I can hear different sounds in each ear'.  But.... they are the same part, the same track, split onto two channels on the desk at mixdown - one panned left, one panned right and both treated with different eq/delay/reverb/compression - another good way to make one part sound BIG.  Kevin Shirley used this technique a LOT on HTWWW.
So I count 2 tracks of drums (so they can be stereo), 1 track of bass, 1 track of vocals, 3 tracks of guitar, leaving one track free for the synth drone and the guitar solo.  No need to bounce, no need to have anything other than 1st gen. tape hiss.

"Dancing Days" is possibly four guitars (or three guitars and a synth) at it's most dense, but again : 2 drum tracks, 1 bass, 1 vocal is only 4 tracks, so plenty of room for four guitars.

"Ten Years Gone" - Wikipedia says Page recorded 14 guitar parts for the harmony section.  I think that's rubbish.. well certainly an overexaggeration.  However this is the first track you've mention that probably does have some track bouncing involved.
Towards the very end there are very clearly two guitars going on in each ear, and then another starts panned centrally.  That's 5 distinct guitar parts, and because it's recorded on 8 track tape, there's obviously not enough discrete tracks for: 2 drums, 1 bass, 1 vocal, 5 guitars and a backing vocal, so somethings going on here.  I reckon two guitars were bounced to one track and another two guitars to another track, leaving two free.  One for BV's, one for the extra guitar at the end.  It's worth noting that 'Ten Years Gone' is considerably hisser than many of the other tracks on Physical Graffiti, so that's probably down to the two second generation bounced tracks.  
It's also worth noting at this point that they didn't have to go through the rigamarole of bouncing all 8 tracks to a separate tape machine - if you haven't filled all 8 tracks you can submix any (or all) of the other tracks onto an empty one and then re-use the tracks you have bounced from.  This is a great way of ensuring you don't get 2nd. gen. hiss on all the tracks - only the bits of a track where you've had to do a bounce.  You might lose a bit of fidelity on the re-used tracks - depends how 'hot' you recorded the original signal.

By the time they got to 'Achilles' there were not only improvements in noise reduction, but they were also using 16 track tape.  Much more 1st. gen. tape to record on.  They may have decided by then to record the drums on more than two tracks.... but I doubt it somehow.  Page seems to be a 'get the sound right in the room and track it' type of producer, rather than spend hours making decisions on what compressor to use on the snare drum at mixdown etc....  Even 'Bohemian Rhapsody' which was recorded on 24 track tape (I've got a copy of that multi too....) only has two tracks of drums.
So, based on their usual formula: 2 drum tracks, 1 bass, 1 guitar tracked with the band, 1 vocal - that leaves 11 pristine tracks for overdubs.
Page was using a much less 'thick' guitar sound and going for 'glassier' tones generally at this time too - less thick means less frequency spectrum filled, which means everything sounds a bit more roomy and separate.  That's be another reason why it sounds cleaner.

8 hours ago, mrlowry said:

With analog there are two things to worry about.  The first is generation loss which is when you copy one tape to another tape when bouncing down multiple tracks to one track to free up recording space, as described by the post above.  The second is the loss that occurs every time a piece of analog tape runs through a machine a little bit of the magnetic material is worn off in the process.  

I did cover this in my previous post:

On 10/17/2020 at 11:30 PM, woz70 said:

The only other noise that will be added during initial recording, or overdubs, is hiss and hum from Amps, electrical (Johnson) noise added by compressors and other effects, the path of the signal through the desk and the tape machines' electronics, and eventual loss of high frequency response of you play the tape back too many times or do too many takes an overdub (this is why Sly and the family stone's recordings are so muffled sounding)

Sly Stone was notorious for going out, getting wasted, inviting a load of randoms to record their parts on the master multi tracks, and then having to erase them the next day.
Totally ruined the tape because of a) too much playback, and b) too much erasing and re-recording.

8 hours ago, mrlowry said:

Queen faced this problem when recording "Bohemian Rhapsody."  They even joked about being able to see through the tape by the end of the recording session

Yes - the multitrack harmony vocals are a nightmare to navigate - their mix engineer had an unenviable job sorting that lot out.  Multiple nested bounces, and because they did it all on one 24 track tape there are no 1st gen. versions of those vocal parts available any more, so they couldn't do what Giles Martin has done with The Beatles back catalogue (they kept EVERYTHING) - go and find the earliest generation of each part and piece it together with Pro-Tools to do fabulous remixes with only one gen. of tape hiss.  Again, shows the skill and diligence of those engineers at Abbey Road.

Finally:

8 hours ago, mrlowry said:

To my knowledge Jimmy Page never used this pristine rhythm track method with Led Zeppelin, probably because it would have slowed down the recording process and disrupted his creativity too much.

That's because Zep generally prepared LOTS before going into the studio.  Most of the arrangements will have been really well worked out, rehearsed and sorted LONG before they went into the recording studio.
Why waste time and money pratting about in a recording studio trying to figure out parts?  Musicians get bored/drunk/stoned and don't stay focussed if you spend too much time recording - you won't get the best, freshest performance. 
Work it all out first, in a much cheaper rehearsal studio.  Use as little studio time as possible, spend as little money as possible.  The end product sounds better, because it's well rehearsed and not made up on the spot, and also you can use that time to plan how best to use the limited track space available to you.
I think that Zep were one of the most successful bands that literally spent the absolute least time possible in the recording studio.

Some bands used the studio as a composition tool : The Beatles, 10CC, Queen to some extent, Jimi Hendrix after Electric LadyLand was built.... but that's a really expensive way of recording an album, unless you own the studio or in The Beatles case, your record company gives you carte blanche and a bottomless cheque book.
 

Edited October 20, 2020 by woz70
Stupid editing.

[woz70]

8 hours ago, mrlowry said:

For an example if you listen very closely to Black Dog it has one guitar part but  that one part is made up of multiple layers of different performances of that one guitar part (probably 5 layers.)  You can hear this same approach but with less guitars on "In My Time of Dying" where two different guitars play the same part.  One has a fuzzier tone and one has a cleaner tone. 

I meant comment on this too, but I forgot.

This is actually a really interesting bit of recording, used a lot nowadays.

There’s actually only one guitar here (the only obvious overdub is when the guitar sound changes during the solos)... but the signal has been split and sent to two different amplifiers - one with a fuzzy tone, one with a cleaner tone, each recorded to a different track.  It would literally be physically impossible to play that slide guitar part exactly the same twice, without making a single mistake or going out of sync over the duration of an eleven minute song. A simple case of record as a band, overdub the solos (and maybe the vocals... you never know...) and Bob’s your uncle.

Well, almost.  If you compare the companion disc version with the album version I think there’s a bit of tape editing going on in there too.  There’s a lot more of that going on in every Zep album than you’d think!

Anyway... nowadays a producer might use a technique called re-amping to achieve a similar sound. What you do is record the guitar signal directly to one track as well as recording the amp used during the recording session. During production this gives you the opportunity to send the clean guitar signal to a different amp to reinforce/improve/change the sound, or to double up the part. Very easy to do with digital recording as you’re not so limited with the number of tracks you have available, and you have a far lower noise floor and a greater dynamic range than even the best analogue tape will ever give you.

[mrlowry]

19 hours ago, woz70 said:

Not an oversimplification at all.  

As a real-world example, here's the actual track setup for Ramble On (the tracks might not be in the order the are on the original multitrack tape, but they are (copies of) the original multi's and it's how I've got them arranged in my studio):

Track 1: Acoustic guitar
Track 2: Bass (Judging by the spill that can be heard it was recorded simultaneously with Drums and acoustic guitar)
Track 3: Drums L
Track 4: Drums R
Track 5: Electric guitar - obviously recorded as an overdub, but it was recorded on a pristine empty track, so only first gen. tape hiss - same as the Bass, Drums and Acoustic Guitar.  Adding this overdub has not added any more tape hiss than was already there, and the same goes for the following overdubs:-
Track 6: Guitar overdub - twinkly guitar but in the pre-chorus, plus one part of the harmony guitar solo - again an obvious overdub (it says so on the track sheet), again recorded on a pristine track so, again, only 1st gen. tape hiss.
Track 7: Vocal - very obviously not recorded at the same time the rest of the band were tracking (the spill you can hear contains acoustic guitar, electric guitar and harmony solo), so an overdub.  Again, only 1st gen. tape hiss.
Track 8: Vocal doing a double of 'Ramble On' for the chorus, plus second part of harmony guitar solo.  Again an overdub, but only 1st gen. tape hiss.

So in this song:
1: no need to bounce any tracks to another and add generational noise;
2: only first generation hiss on EVERY TRACK;
3: only 8 tracks available; and there are still points with four guitars playing simultaneously, thanks to good planning of what each track would be used for.

Just to reiterate: overdubbing on a pristine track will not add any more tape hiss than is already there.

So that covers:

Next point:

No. Black Dog has 3 quite distinct guitar parts in all.  One panned hard left, one panned hard right, and finally the solo.  The 'thick' sound is all down to how it was recorded, and how the mixing engineer dealt with processing those tracks during mixdown.  Lots of people (you, and a few people I have worked with amongst them) seem to think that you fatten up a guitar sound by recording multiple stacked version of the same part.  Weirdly that can actually make a track sound thinner, and usually two versions of the same part recorded with different amps/guitars and panned apart sounds much fatter than 5 guitars playing the same thing - which, depending on the guitarist can often end up sounding like a right mess.

I have done, for over 40 years.

I've covered this above - overdubbing does NOT (necessarily) mean more hiss.  The apparent 'muddiness' is not down to fidelity, it's down to eq choice during tracking and at mixdown, which means that's exactly how Mr. Page wanted it to sound.

"Celebration Day" is definitely complex, but there are only ever 3 guitars playing at once, usually panned hard Left and Right, sometimes one in the middle too.  You're probably going to say 'but the guitar solo is surely two guitars - I can hear different sounds in each ear'.  But.... they are the same part, the same track, split onto two channels on the desk at mixdown - one panned left, one panned right and both treated with different eq/delay/reverb/compression - another good way to make one part sound BIG.  Kevin Shirley used this technique a LOT on HTWWW.
So I count 2 tracks of drums (so they can be stereo), 1 track of bass, 1 track of vocals, 3 tracks of guitar, leaving one track free for the synth drone and the guitar solo.  No need to bounce, no need to have anything other than 1st gen. tape hiss.

"Dancing Days" is possibly four guitars (or three guitars and a synth) at it's most dense, but again : 2 drum tracks, 1 bass, 1 vocal is only 4 tracks, so plenty of room for four guitars.

"Ten Years Gone" - Wikipedia says Page recorded 14 guitar parts for the harmony section.  I think that's rubbish.. well certainly an overexaggeration.  However this is the first track you've mention that probably does have some track bouncing involved.
Towards the very end there are very clearly two guitars going on in each ear, and then another starts panned centrally.  That's 5 distinct guitar parts, and because it's recorded on 8 track tape, there's obviously not enough discrete tracks for: 2 drums, 1 bass, 1 vocal, 5 guitars and a backing vocal, so somethings going on here.  I reckon two guitars were bounced to one track and another two guitars to another track, leaving two free.  One for BV's, one for the extra guitar at the end.  It's worth noting that 'Ten Years Gone' is considerably hisser than many of the other tracks on Physical Graffiti, so that's probably down to the two second generation bounced tracks.  
It's also worth noting at this point that they didn't have to go through the rigamarole of bouncing all 8 tracks to a separate tape machine - if you haven't filled all 8 tracks you can submix any (or all) of the other tracks onto an empty one and then re-use the tracks you have bounced from.  This is a great way of ensuring you don't get 2nd. gen. hiss on all the tracks - only the bits of a track where you've had to do a bounce.  You might lose a bit of fidelity on the re-used tracks - depends how 'hot' you recorded the original signal.

By the time they got to 'Achilles' there were not only improvements in noise reduction, but they were also using 16 track tape.  Much more 1st. gen. tape to record on.  They may have decided by then to record the drums on more than two tracks.... but I doubt it somehow.  Page seems to be a 'get the sound right in the room and track it' type of producer, rather than spend hours making decisions on what compressor to use on the snare drum at mixdown etc....  Even 'Bohemian Rhapsody' which was recorded on 24 track tape (I've got a copy of that multi too....) only has two tracks of drums.
So, based on their usual formula: 2 drum tracks, 1 bass, 1 guitar tracked with the band, 1 vocal - that leaves 11 pristine tracks for overdubs.
Page was using a much less 'thick' guitar sound and going for 'glassier' tones generally at this time too - less thick means less frequency spectrum filled, which means everything sounds a bit more roomy and separate.  That's be another reason why it sounds cleaner.

I did cover this in my previous post:

Sly Stone was notorious for going out, getting wasted, inviting a load of randoms to record their parts on the master multi tracks, and then having to erase them the next day.
Totally ruined the tape because of a) too much playback, and b) too much erasing and re-recording.

Yes - the multitrack harmony vocals are a nightmare to navigate - their mix engineer had an unenviable job sorting that lot out.  Multiple nested bounces, and because they did it all on one 24 track tape there are no 1st gen. versions of those vocal parts available any more, so they couldn't do what Giles Martin has done with The Beatles back catalogue (they kept EVERYTHING) - go and find the earliest generation of each part and piece it together with Pro-Tools to do fabulous remixes with only one gen. of tape hiss.  Again, shows the skill and diligence of those engineers at Abbey Road.

Finally:

That's because Zep generally prepared LOTS before going into the studio.  Most of the arrangements will have been really well worked out, rehearsed and sorted LONG before they went into the recording studio.
Why waste time and money pratting about in a recording studio trying to figure out parts?  Musicians get bored/drunk/stoned and don't stay focussed if you spend too much time recording - you won't get the best, freshest performance. 
Work it all out first, in a much cheaper rehearsal studio.  Use as little studio time as possible, spend as little money as possible.  The end product sounds better, because it's well rehearsed and not made up on the spot, and also you can use that time to plan how best to use the limited track space available to you.
I think that Zep were one of the most successful bands that literally spent the absolute least time possible in the recording studio.

Some bands used the studio as a composition tool : The Beatles, 10CC, Queen to some extent, Jimi Hendrix after Electric LadyLand was built.... but that's a really expensive way of recording an album, unless you own the studio or in The Beatles case, your record company gives you carte blanche and a bottomless cheque book.
 

Wow,  That's a lot of great information.  So do you feel that the slightly muddy or murky sound on many Led Zeppelin recordings is a creative choice and not a limitation of the recording technology?  

[woz70]

1 hour ago, mrlowry said:

Wow,  That's a lot of great information.  So do you feel that the slightly muddy or murky sound on many Led Zeppelin recordings is a creative choice and not a limitation of the recording technology?  

Listen to music recorded by other bands that recorded in the same studios as Zep used during the same period.  Do they sound murky or muddy?  That should answer your question.

(This is actually a bit of a red herring... because Zep used studios all over the place, as well as the Ronnie Lane and The Rolling Stones mobile studios, often recording basic tracks in one studio and overdubs in another! But I digress....)

it’s a blend of engineering choices, equipment choices, mixing choices, mastering choices, and a result of the hearing of everyone involved in all of those parts of the recording process.  Some people like bright, clinical sounding records, some like dark, warm sounding records.  Your ‘murky or muddy’ is another persons ‘thick and warm’.  In my opinion the only song that really does sound murky is ‘four sticks’.
 

The only palpable issues with the recording technology of the time is the way they had to deal with bass response (Too much bass and the needle skips out of the groove on an LP) and the fact that your songs with the greatest dynamic range have to be nearer the outside edge of an album (due to the physics of vinyl records - angular velocities and track-packing etc.).

They were unique in that they had the same producer throughout their career, who was also a band member. This is both an asset - for consistency of production values and overal continuity of sound - and a liability, because playing loads of really loud concerts in front of stacks of amplifiers for hours at a time is not going to do great things for your hearing.  (This may be another explanation for the brightness of the sound of the ‘Presence’ recordings.)

Edited October 20, 2020 by woz70