Jethro Tull in surround sound (2003)

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Jethro Tull in surround sound (2003)

Beitrag von Laufi » Di Dez 01, 2015 11:38 pm

Jethro Tull in surround sound - an essay about a quadrophonic experience

Well, this essay results of what I've been inventing and doing in lots of my spare time over the last 2 years. I've been learning and experiencing very different (and also difficult) things and finally thought I could share this with my readers. The following facts are sometimes not easy to understand, as they have technical informations, but I try to explain things as good as I can.

Surround sound
I have always been interested in 'sound' things since I was a teenager, as I've been (singing) in bands and while I wouldn't declare myself as a proper musician, I think I've had some useful experiences in such things when I played on stage or recorded music. I always wanted to know how things work and learned a lot simply by doing or watching how technicians I worked with improved things.
My first experiences with multichannel surround sound were back in 1999 when I bought my first DVD player and a few weeks later a home cinema receiver and speaker set-up that was able to decode multichannel recordings like Dolby Digital or dts 5.1. Movies were sounding (and looking, but that's another story) great with all these effects and only a short time later, I realized that watching a movie 'only' in stereo had something missing. It didn't take long that I had my first surround sound experience with music: Pink Floyd's "The Wall" was my first music DVD - with a few hundreds to follow. While 'The Wall' is still a film (with great sound, at least for that it's 20+ years old), lots of concert DVDs followed. Some of them had poor sound, lots great and others even fantastic sound!

Jethro Tull music in surround sound
In 2001, the first proper Jethro Tull DVD, "Living With the Past" was released. I happened to get an advance copy a few weeks before the release and -being very curious about it- was quite disappointed when it came to the sound. Don't get me wrong, I like the DVD, but I was expecting a surround sound on a concert film as well, while this DVD 'only' has a (fine) stereo soundtrack. I was curious about the voice in the center speaker, the flute from back left and the 'Aqualung' guitar solo flying in from front left, turning to the rear right, but - nothing!
Anyway, the Jethro Tull surround experience had already been there, but I simply didn't recognize it. It all started some 30 (!) years ago.
Some of you may know that I'm a serious record collector that is always looking for rare Jethro Tull records, mostly stuff like singles from foreign countries, promotional records, etc. I knew about two quadrophonic Jethro Tull 'quadradisk' albums and had them in my collection since the middle of the 1990ies - without really knowing what it's all about. These albums are 'Aqualung' and 'Warchild' - the first being famous for having a rough demo version of "Wind-Up" instead of the regular album version on it. This version sounds very interesting and was finally re-released on the re-mastered 'Aqualung' CD back in 1997. More on differences to the regular albums later. Having the quadradisk albums in the rack for quite a few years I found out more by accident about this quadrophonic system when I was doing an internet search (on a very boring sunday afternoon, I think).

The quadrophonic experience
I want bother you with too many technical things, but here's some basics. The quadrophonic systems of the seventies were mainly an american (and japanese) thing - only some freaks used this here in Europe. And: there were lots of different systems. Some of them used matrix based multichannel, some of them had discrete channels. I'll focus on the quadradisc CD-4 system on which the Jethro Tull quadrophonic vinyl records were released. I found some quadrophonic websites and -forums that had great information how all this works. Praise the internet, really!
Basically, a CD-4 vinyl record is looking like a normal one, but it has the information for four channels on it. It can always be played with a normal turntable (in stereo, of course), but I wanted to know how I can listen to the four channels. The system works as follows:

The quadradisc has the information for the rear channels (channel 3 and 4, left and right) modulated in frequencies above 30 kHz (up to 45 kHz, I think) - which the human ear simply can't hear - you'll hear up to about 20 kHz if you're a teenager and maybe 'only' up to 15 kHz if you're an older person. So basically, the two more channels are always there, but you simply can't hear them. Well, it still isn't as easy as this, as the normal stylus on your turntable does frequencies up to about 22 kHz and only a special one can play these needed high frequencies. This special stylus is made in a 'Shibata' style and -of course- isn't manufactured anymore in 2002 (when I started researching), as we're talking about technology from about 1972. How I solved this problem, later ...

After the Shibata stylus plays all the frequencies of the CD-4 record, the signal is sent to a demodulation unit. This unit get's a two channel signal from the turntable, demodulates the information in the high frequencies and sends four channels back: the main channels and the demodulated extra channels, which are now in the normal frequency range that the human ear can hear.

Next you need is an amplifier that can handle four signals at once and of course four speakers. So you won't be succesful with your stereo. The original gear were special quadrophonic amps that could handle these four channels - as well as a normal stereo signal. Some of them had the demodulation unit already built in. Of course there's also the possibility to have two stereo systems, one playing the main channels, the other one the rear channels.

Getting the equipment ...
Ok, I had these two quadrophonic albums of my favourite band and was just curious how they were mixed in the original intention of the format. I just needed (and wanted) to get the equipment - which wasn't as easy as it sounds. I live in Germany and as I wrote before, none of the quadrophonic formats were succesful in Europe, so I couldn't just look at a flea market (or even in a store) to get what I needed. First thing was solved very easily. I didn't have to look for a quadrophonic amplifier, as most modern home cinema receivers have six-channels anoloque inputs to get a decoded signal from a DVD player. You simply use four of them, the main and the rear signals and that's it! I've got a fine Yamaha DSP AX-2 at home which can do nearly everything, problem solved!
Up to the demodulator. This wasn't easy, but -praise the internet again- I was tracking ebay for weeks and finally got one - even from a German seller, which made the transcation (in case of sending parcel and money) a bit easier. The unit is a JVC DD5, which seems to be a good one, at least this is what lots of quadrophonic experts on the internet think. It wasn't cheap, but I got it still for a reasonable price that I could afford and -more important- it has a switch to get it working with 220V (in America they use 110V) and it was in good shape (and working!), too.

The bigger problem was the Shibata stylus. After some research, I luckily found out that I didn't need a new or special turntable - the stylus works basically with every turntable. BUT - absolutely no chance to get such a stylus! All the manufacturers that did these stopped building them around 1980. I even went to a hi-end hifi-store here in Cologne where real freaks and enthusiasts are working and asked for such a stylus. They had big questions marks above their heads and showed me their oldest clerk, which 'usually knows erything'. Hoorah, he even know what I was talking about, but couldn't help me in any case. "We sold about 5 systems around 1975, you're a few decades too late ...".
Again, the internet should help me. The quadrophonic scene is still there - mainly americans that still have their equipment and as a stylus is a thing that is worn out after some time, there's need for these 'quaddies' to get a new one from time to time. So I found a person that builds these by hand (I think he modificates existing ones) and sold me an Audio Technica Stylus for $50 that would work for quadrophonic sound - and it did!

... and setting it up.
Well, finally, after some months of investigating and spending some money I had all I needed to play these -well- two quadrophonic records!"Time and money for just 80 minutes of music?" you might say - and that's exactly what my girlfriend said. But anyway, I'm sure some of you understand my will to set this up.
So I did, which was basically very easy: install the stylus, plug the turntable into the demodulator and plug the four channels from it to the amplifier. The demodulator has a light that indicates that it is getting a quadrophonic signal, I put the 'Aqualung' album on, got a signal and .... it sounded shitty! Well, not _really_ shitty, but I couldn't define a surround sound at all. I got signals from all four speakers, but this was everything but discrete! It just sounded like stereo, but from all four speakers and I didn't think that it was anything intended.
Some research again (praise the inter ...) and I found out that the demodulator has to be set-up (there are some knobs on the back and one below the unit) and the best thing to do so would be with a special CD-4 test record. Hm, a test record for a specials freak system from _the past_ is -you guess it- some of the most impossible things you can get in 2003. I had to be patient again.
I found some websites were "quaddies" were trading and selling quadrophonic records and finally two people that had spare copies of test records. I e-mailed them both, being willing and able to pay some good money again (close to my goal), but they sadly didn't reply.
What would a freak (at least I was surely on the way being one) do without ebay? Right! It took half a year until a Pioneer CD-4 test record appeared on ebay. The seller was american and wanted to sell to the 'United States only' - luckily he believed me when I sent him an e-mail promising that I'd be a good partner and would pay the extra postage, etc. $10 for the record and another tenner for the postage, one week via air-mail (how long a week can be) and I had everything I needed - it took only about two years!

The knobs I mentioned are to do the following: with the knob below the demodulator, you have to set-up the 30 kHz signal that the unit gets from the turntable. This is important, as if you don't level this exactly, you might get some serious distortion. The other knobs on the back are for separating the channels. There's a left and a right separation. The test record provides test tones in high frequencies that help to set-up the 30 kHz level and the channel separation (nearly) exactly. It took a few hours (as I haven't done this before - a real 'quaddie' probably does this in a few minutes) and my cat (as well as my girlfriend) went nuts due to these high notes, but it worked pretty well in the end. And finally - I sat back, relaxed and had my first quadrophonic Jethro Tull experience sometime in january 2004!

What's the goal?
Ok, I was able to listen to these two vintage surround sound records now. Both albums are in a pretty good shape if you look at them (I've also got a spare 'Aqualung' quadradisc which looks not as good as the other one, but should at least provide a back-up if there's problems with the first one) and also if you play them in stereo (which I did once after I bought each album). But playing them quadrophonic provides some problems. The quadradisc system is quite sensitive and the more you play it (or if you play it with a worn stylus) especially the rear channels will suffer - and that was surely not what I wanted to happen! I read about people transfering vintage quadrophonic records to recent digital surround formats, so -having also the equipment and some knowledge to do such things- I decided to make up my own digital surround edition of Jethro Tull's 'Aqualung' and 'Warchild' albums. The most popular format for this is dts (digital theatre surround) which also works on a normal CD, but in 44.1 kHz (compared to a DVD which has 48 kHz). You only have to have your CD player connected with your home cinema amplifier with a digital cable - NEVER play a dts CD with a normal analoguw connection, you only hear noises which might destroy your speakers!
I decided to use this format, as well as the 'proper' 48 kHz format to put it on a DVD later.

The transfer and the work
First thing was to transfer the audio material onto my computer (which is kind of a audio/video homestudio machine) and that lead into the first problem. I've got a fine soundcard (Terratec DMX 6fire 24/96), but it doesn't have multi-inputs, which I needed to transfer the four channels onto the computer. My first try was to play the record twice, which worked, but wasn't succesful in case of doing it perfectly. I played the record first recording the front channels and a second time to record the rear channels. But you can say that a vinyl record never plays _exactly_ the same speed twice (except maybe if you have a thousands of dollars worth turntable, which I don't have), so there was a (very slight) difference on the second run, which was some thousands of a second faster and I decided to try a different way instead of pitching the rear channels to have them synchronized. So next try was recording the front channels with the computer and the rear channels with a DAT machine, which meant that I did two digital recordings simultaneously to transfer the DAT recording with channels 3 and 4 into the project onto the computer later. This worked pretty well. The main channels were recorded in 32bit float, 48 kHz onto the computer, the rears 16bit, 48 kHz using Super Bitmapping onto the DAT machine. After that, the rear channels were transferred onto the computer in 32bit float, 48kHz using an optical digital cable. Perfect, the four channels were on my harddisk and it took only a few minutes to have them synchronized!

Now the real work started! Vinyl records -even if they're in good shape- always have clicks and plops, so there was the need to remove (most of) them. But first I checked the speed and the pitch of the recording, as nearly no turntable runs in the exact speed. I copied one track from the regular CD version into my project and compared length and speed. I had to pitch the qudrophonic recording with a factor of about 0.9963, which means it ran a bit too slow. I bet you wouldn't hear this without comparing, but anyway, I wanted to do this perfectly from the first moment.

Removing clicks and plops isn't easy, as you simply can destroy your recording with de-clicking it too much. The declicker may remove parts of the music as well, mainly percussion instruments. So I had to be careful to find the right settings. The result was pretty succesful - the recording now sounded fine and even if there were still some clicks if I listened to the music over the headphone, they weren't very loud - you hear them in quiter parts, though. Another problem occured: obviously, there was some slight distortion from time to time on the right channel, which simply isn't removable without changing much of the original recording - so it's still there, as the main goal was to have the quadrophonic mix as intended by the producer. I wanted to know why this distortion was there and found out that usually it could only be from a) the record being worn out or b) the demodulator not being set-up exactly or the stylus not doing a perfect job. It seemed to me that b) is the answer, but after some re-checks it was obviously that there was no way to set-up the gear more perfect. Then I compared both 'Aqualung' LPs and found out that the distortion was exactly on the same parts of both LP's - obviously a problem of the original mastering or pressing. Anyway, compromise: slight distortion on the right channels - no big thing, as it's not very much distortion.

At this point I already decided to do a second version with a different own mix, trying to fill the two missing channels (center and lfe speaker) of the modern surround system and tune-up some frequencies. Also the quadrophonic system worked only if you were sitting "exactly" in the middle of the four speakers. So the first work on the recordings was only removing clicks, plops and hiss and balancing the volume. The right channels were also a bit quiter than the left channels, which I fixed and I also balanced the loudest parts to about 0dB. That's all I did on the recording so far and it was time to decode to dts CD for a first listening experience!

The result
My first run through the cleaned-up 'Aqualung' album in quadrophonic sound was really exciting. Lots of good surround effects and I heard the album that I probably listened to a thousand times in a very new way. I worked out the 'Warchild' album in the same way and went on to do the 5.1 mixes.
For this I changed some frequencies and the volume of the channels, as especially the surround speakers seemed to be a bit too loud. I also mixed down a center channel from the front speakers with only the middle freuquencies in it to get mainly the voice from the center. The lfe channel got the low frequencies from the front channels and after some fine-tuning and mixing I was ready to encode and burn the dts 5.1 mix to CD - sounded great and even a bit better to my eras than the quadrophonic 4-0 mixes.

The review
Well, you probably all know the music, so I don't have to review it very much, but I'd like to review the surround sound of the recordings. It is well done and after a few hearings, I knew why the 'Aqualung' album is one of the best quad albums in the 'quadrophonic scene'. The engineer worked a lot with having the flute and especially the strings on the rear 'effect' speakers, which sounds really great. For example, on 'Cheap-Day Return' you have the voice coming from front and the strings separately from the back. The flute solo in 'Locomotive Breath' comes from the back as well and the guitars (rhythm guitar and the one that plays the fills) are separated. The highlight is the flute solo in 'My God', which has various flutes and the choir (la-la-la-la) coming from different speakers to make you feel being really in the midlle of what's happening.
The 'Warchild' album has even more string arrangements, which mostly come (as well as accordeon and piano parts) from the rear speakers. The sound on both albums is quite excellent for that it has been taken from such old records. Of course, hi-fidelity wise speaking, you can't compare them to the new re-mastered CDs, but anyway, these are 'only' stereo - and for the surround listening experience, a few clicks and very little distortion is ok. Best would be if Ian or EMI would decide to remaster and release these recordings on DVD-Audio or SACD (Super Audio CD) -which both can hold multichannel- as some other artists did (I've got Queens 'A Night At The Opera' on DVD-A and it sounds superb!), but it seems that this is only a wish and won't happen - see next chapter.

Ian Anderson on surround sound
Here's a part of an interview from classicrock.about.com:
classicrock.about.com hat geschrieben:Have you ever considered doing any DVD-Audio or DTS releases?

It's sort of inevitable, but I certainly wouldn't be going back to do surround sound mixes of all Jethro Tull's albums. I just wouldn't. Not only would I not want to do it personally because it's an enormous amount of work; it just wouldn't capture, it would never sound the same. I actually don't really like surround sound music. I've worked with the medium extensively. In the early 70s, we did three albums, which I mixed in quadraphonic, and I found it a pretty daft business, really! I decided it was a bit irritating in order to justify the medium -- scattering instruments around in the audio field in such ways that makes people feel they don't defile you for money by hearing some guitar solo coming over their left shoulder. What's the point? It's actually irritating acoustically, disruptive and confusing. I'm not a big fan of surround sound in that context.

In a live performance, there's some justification for doing it. There's some justification in wrapping some of the sound around the ambience, but people would listen to my mixes and say, 'Oh they're far too subtle, it just sounds like stereo with a little bit of reverb coming from behind my head.' What the hell do you want? If you want to go and see some psychedelia in action, then I suppose you could surround sound mix some of that sort of music that might go with it. But most music I don't think really benefits from it at all.

I'm all for improving the bit rate of ...future music, DVD or whatever you want to call it. I think if we're ever going to do some surround sound, I'll probably limit it to a Best Of album. I'm not sure I'd want to go back and tamper with the stereo mixes; you'll never get it to sound the same again, that's the thing. Mostly, analog tapes are unplayable; there's simply no chance of going back and working with all the analog tapes. The oxide started falling off years ago (laughs) and they're virtually unplayable now. I do have two or three that I did copy over to multi-track...for instance Aqualung, and I think, Thick As A Brick, and a few others were copied. We did some multi-track-to-multi-track transfers, so they ought to be good for a few more plays, but certainly we don't have all the albums.
Sounds not good for future surround releases. Ian is talking about 'three' albums, but there were only two quadrophonic albums released. From what I could research, 'Minstrel In The Gallery' and 'M.U. - The Best Of' were announced as quadrophonic CD-4 releases but never released. 'Aqualung' on 'M.U.' has the quad mix on it (in stereo) and 'Song For Jeffrey' is a slightly different mix, compared to the versions on 'This Was' and 'Living In The Past'. This could be the proof for the existance of a quad mix of that album - it also fits in the timescale, as well as 'Minstrel' does (both released Quadradisc albums were mixed in 1974 and the technology became available about 1972 - so it makes sense that the missing quad album(s) were from after 1974) and we know that Ian sometimes doesn't remember exactly facts from 30 years ago!

The quad mixes were probably done at the JVC Cutting Center in the RCA building in Los Angeles. The main engineer was Daryl Johnson, who stated that Ian Anderson brought the master tapes personally under his arms and participated (if not supervised) the sessions himself. Still a mystery why -if Ian participated- the 'Wind-Up' demo-version appeared (obviously by mistake) on the quad 'Aqualung' album. Ian's recent statement in the about.com interview about the quad mixes sounds a bit like he was 'forced' to do them, while in an interview from New Musical Express 1 February 1975 Ian states "Our albums will continue and come out as sound albums, in stereo and quadrophonic, ..." and in Circus Magazine, November 1974: "...Not only is War Child recorded in quadraphonic sound--and Ian urges all music fans who can afford a quad unit to buy one...". This sounds as if Ian was interested in the quadrophonic system - anyway - so no idea what Ian's real thoughts about this were back in the seventies or in general. Maybe it's just his mind that changed in this case - on the other hand: the only recent Jethro Tull DVD 'Living With The Past' that has a 2001 concert on it wasn't produced in surround sound, so generally there seems to be be not much interest in it.

Jethro Tull quadrophonic discography
Here's a discography of all known quadrophonic Jethro Tull recordings:

Aqualung
Quad mix probably done by Ian Anderson at the JVC Cutting Center in the RCA building in Los Angeles with engineer Daryl Johnson in 1974. US only release.

CD-4 LP (Warner Chrysalis CD4 1044) - Release date: 2 April 1975, deleted 1978.
Probably two slightly different releases exists, one has only the Quadradisk logo on the label, the other one has the statement "It is the the opinion of the producer that, wheras this Quadradisc album may be played without damage on existing stereo equipment, best results may be achieved only by playing on a CD4 discrete quadriphonic system. Best results on stereo equipment are achieved by playing a stereo disc.".
The LP comes in a gatefold sleeve with a lyric insert, it has the Quadradisc logo on the front cover on the left. Green Chrysalis label. 'Wind-Up' is a different (demo) version, which was released on the remastered 'Aqualung' CD as 'quad version' in 1997.

Quadraphonic 8-Track Cartridge (Chrysalis 0797)- release date not known
The 8-Track cartridge version, which has probably the same mix, which I'm not finally sure about, as I don't have this cartridge.

Warchild
Quad mix probably done by Ian Anderson at the JVC Cutting Center in the RCA building in Los Angeles with engineer Daryl Johnson in 1974. US only release.

CD-4 LP (Warner Chrysalis CD4 1067) - Release date: 2 April 1975, deleted 1977.
Probably two slightly different releases exists as mentioned for 'Aqualung'. The statement can be found on the label, as well as on the back sleeve. The LP comes with a lyric insert, it has the Quadradisc logo on the front cover on the right. Green Chrysalis label.

M.U. - The Best Of
CD-4 LP (Warner Chrysalis CD4 1078) - Never released, but announced
This was never released and I don't know any person that ever heard it.

Minstrel In The Gallery

CD-4 LP (Warner Chrysalis CD4 1082) - Never released, but announced
This was never released and I don't know any person that ever heard it.

(from http://www.laufi.de website around 2003)
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