Positive Feedback ISSUE 43
may/june 2009

The Greening of SACDs, (gulp) CDs and other digital madness
by Teresa Goodwin

Sony/Japan Green Label SACDs

Remember the controversy over painting the edges of CDs with green felt-tip pens? The aim was to improve sound quality by absorbing stray red laser reflections that might cause jitter in the data read from the disc. Sony’s audio division in Japan is now backing an intriguing project which tests the theory.

A batch of new SACDs from Sony Music has green labels. This is not "green" to help the environment; it’s to help audio quality by lightening the burden on the servo mechanism for the player’s tracking head and to introduce fewer errors for the player’s error correction to handle.

Sony UK’s audio guru, Eric Kingdon, was demonstrating a high-end Sony system at IFA in Berlin, using a green label SACD version of the L.A. Allstars (Birdland: XSCL-10004).

Other green label SACDs include the L.A. Allstars "Afro Blue" (XSCL-10005); Sacred Rhythm of Bali (XSCL-10007); Masayoshi Takanaka "The Man With The Guitar" (XSCL-10006); Allan Holdsworth "All night wrong" (XSCP-1000); and Emi Fujita "Camomile Best Audio" (PCCA-60019 from Pony Canyon).

The project was inspired by Sony’s Japanese audio engineers Takashi Kanai and Motoyuki Sugiura. Sugiura has compared the new green label SACDs with the original SACDs of around five years ago and finds the difference "amazing."  Sony plans public demonstrations at audio shows so that interested consumers can judge for themselves.

Greening my own SACDs and (gulp) CDs

In the past one of the many tweaks I tried in an effort to make CDs listenable was the "AudioPrism CD Stoplight by Clear Image Audio™ Compact Disc Edge Treatment" green pen, which at the time I felt helped but it did not totally eliminate Digitalis from CDs. It's over a decade since I tried it and with Sony releasing Green label SACDs based on their research with green pen treatments I thought it was a good time to try it again.

The CD Stoplight pen retails for $24.99, AudioPrism claims it reduces the scattered reflections of the laser beam and increases the signal-to-noise ratio of the detected laser. The result is an overall increase in clarity and a significant decrease in the edginess in the sound of many compact discs. You will notice an immediate and dramatic increase in clarity, resolution, and ambience.

AudioPrism discovered that during playback, a significant quantity of stray laser light bounces around inside a CD player. This stray light eventually finds its way back to the pick-up assembly, creating jitter. CD Stoplight was developed to passively reduce the the effects of stray light that ultimately causes jitter. By absorbing the stray light at the transport passively, rather than attempting to reduce it's effects downstream electronically, jitter is reduced at the source-keeping it out of the playback chain.

Packaged with a special applicator, CD Stoplight is easy to apply. It is non-toxic, environmentally friendly and will not flake or peel. Compact Discs treated with CD Stoplight sound more neutral, less edgy and significantly more open.

In my research on the Internet I found a cheaper alternative. Metralla, a poster at the Audio Asylum recommend the Uni Posca marker which is a water-based green poster paint pen, he said they are available at art supplies stores for about $3. These come in dark and light green and are said to be identical to the CD Stoplight pen but without the groove in the tip of the applicator. I didn't try this less expensive alternative as I felt the groove in the tip was important for me as I am a little butterfingered and a bit of a klutz.  If you try a pen other than CD Stoplight make sure it is water based so you can clean up mistakes, which you will make!

Also AudioPrism claims the CD Stoplight pen uses a proprietary plastic coating and is safe for plastic, so it may be safer than a less expensive water based green poster pen?

Follow the instructions included with the pen or read the PDF from AudioPrism's website http://www.audioprism.com/cd_stopight_application.pdf

Green SACDs and CDs, before and after treatment

For the tests I used the Yamaha DVD-S18/00 DVD-Audio/SACD Player through the AMC CVT1030 "tubed" Preamp on Sennheiser's HD-265 Linear headphones and Infinity Reference Kappa 7 speakers.

The first thing I did was play one of my favorite SACDs: Virgil Thomson's The River and The Plow That Broke the Plains - Leopold Stokowski conducting The Symphony of the Air. Then I removed the SACD, treated it with CD Stoplight and waited the required 5 minutes for the ink to dry and put it back in the player.  Right away I noticed a considerable increase in volume!  Once I lowered the volume to a level comparable to the before treatment level I also noticed the bass was warmer, the performing space was "airier", the outline of the instruments seemed more defined and the dynamic attacks were sharper. It appears to smooth out the sound, increase ambiance and make percussive attacks more exciting.  All this from a green ink ring around the outside of the disc, amazing!

Next I tested a CD. I haven't owned any CDs in years and even swore I would never buy a CD again. But it seems most people still listen to CDs and want to know how products sound playing CDs so I thought maybe it might be nice to have a small collection of them. This is my 14th time to try CDs, they seem to get a little better each time but never fully satisfy, at least the gross strident string tone of CDs is mostly gone on better CDs on the Yamaha player so playing "the right" CDs was not too uncomfortable. I checked quite a few CDs out of the library to see if I would be willing to actually invest money in a small CD collection. The sound quality ranged from dreadfully awful to very good but I couldn't treat these library borrowed CDs with CD Stoplight so I bit the bullet and bought some. I picked up some music I was interested in that was not on SACD or high resolution downloads during Borders' CD and DVD Inventory Clearance sale and purchased a few others used at very low prices on the Internet. I even got a DSD recorded Telarc that was never released as an SACD.

I selected Chris Isaak's analog recorded Heart Shaped World as this is one of my best sounding non-audiophile pre-recorded cassettes, and I thought it would be good to have a back up copy as Nakamichi cassette deck parts are getting scarce.  The CD untreated was pale in comparison, there was more resonance in Chris Isaak's voice and more wood sound on the box of his acoustic guitar on the cassette. However when I treated the CD I noticed CD Stoplight brought the CD much closer to the realism of the pre-recorded cassette.  The greened CD sounds wonderful and quite enjoyable, not high resolution but neither is the cassette. The importance of this test was to compare two low resolution formats, one I enjoy (cassette) and one I historically have had problems listening to (CD). The fact that this CD sounded good enough that I have since played it again means that the combination of hardware improvements and the use of CD Stoplight might just mean I can occasionally enjoy a CD.

Up next I greened another CD, this time a DSD recorded one Telarc never released on SACD even though it is recorded in Surround Sound, the title is "From The Heart" by Erich Kunzel & the Cincinnati Pops. This is perhaps the closest to live sound I've heard from CD, no it doesn't have anywhere near the resolution of a Telarc SACD but the strings are smooth and the sound is pleasant.  The most interesting thing is I listened to orchestral strings from a CD and they were not unbearably strident.

Next I greened many more SACDs and CDs and in every single instance the difference after greening was a marked improvement and often a very profound difference. This stuff actually works, It increased ambiance, soundstaging, transit response and overall enjoyment of the music on every single SACD and CD I've treated and I have decided to treat my whole collection. On some discs I noticed an increase in volume. The attack of both low frequency and high frequency percussion instruments was increased and more lifelike on greened SACDs. I didn't really notice this effect so much on greened CDs, could it be the greater "base" resolution of SACDs?

Warning, applying CD Stoplight can sometimes be a royal pain. Make sure the disc is clean and if it has a smooth edge the ink goes on quite well. But not all discs have smooth edges, both CDs and SACDs are basically sandwiches and sometimes the bottom edge does not line up exactly with the top edge and when they do line up correctly sometimes they have rough edges making them had to coat with ink, requiring multiple treatments. When you start treating one of these problem discs you will start cursing both me and AudioPrism, I know I did, that is until I played the disc, it was worth the trouble! Also make sure you have a couple of wet paper towels and a couple of CD cloths to clean up messes and boo-boos. You will have plenty of both! If ink goes where it does not belong it comes off easy with water, that is before it dries.

I highly recommend CD Stoplight with the above caveats, it will greatly increase your listening pleasure. If your not ready to spend $25 for what the "bits is bits" crowd call a voodoo tweak and you have steady hands try the cheap Uni Posca green marker.

General preliminary impression of my 14th trial with the CD format

I have very selectively purchased a dozen CDs, some audiophile, some standard issues and the overall sound is not unpleasant after treatment with CD stoplight especially with non-classical music. Many orchestral CDs still had strident strings even after CD Stoplight treatment but the stridency was greatly reduced.

I also listened to many more CDs I checked out from the library and the better CDs I can enjoy if I didn't listen too closely, the worst ones are still grindingly irritatingly bad. Some of the things that really irritate me with the CD format buildup over time so it is too early to tell, as real dissatisfaction in my prior CD trials usually didn't totally set in for about six months, so if I still like the small CD collection I acquired by early 2010 then this was a success, if not it will be my 14th failure with CD. I may never actually be in a position recommend the CD format for critical listening, but it is possible I may actually be able to coexist with them, at the very least as background music. This is the most encouraging sound I have heard from CDs after 25 years of trying. I wouldn't have even bothered with a CD trial if SACD/CD hybrids had replaced CD as they were designed to do. This time I am doing something different, the CDs will be filed separately from my SACDs, I will not be expecting the same involving musical presentations my SACDs deliver but will use CDs more for background music, this I hope will insure that they will have a greater success rate of staying in my collection. Time will tell.

MP3 at higher bit rates gets another trial

Late last year I deleted all my low resolution MP3, WAV and AIFF music files from my computer after selling my iPod, since then the lowest resolution computer music file I had was 24 Bit 88.2kHz. Recently I subscribed to BSO's Digital Music program to get their their concerts as 24 Bit 88.2kHz music files. https://positive-feedback.com/Issue43/bso.htm  They also had older concerts as 320kbps MP3 music files and since they are included in my subscription it costs me nothing to download and if I don't like the sound quality I can delete them. It turns out many of they sound quite good, in fact even better than the greened CDs above.

About the time of my success with the BSO 320kbps MP3, I got another email asking me to rejoin eMusic.com and offered 50 free music files as an incentive. I took them up on their offer as I remembered that they keep your purchases for a year and one can re-download them at any time as often as needed. So I reclaimed much of the MP3's I deleted last year by downloading them again at no extra cost, I then downloaded my 50 free music files and I signed up for 100 music files once every three months for $24.99, thats only 25 cents per file. Or to put it another way $1 for a four movement symphony. Their downloads are 192kbps VBR using LAME3.96 MP3 encoder, the best sounding I've heard so far are from Lyrita, Reference Recordings, Telarc Sheffield Lab and BIS. Many of these sound much better than one would expect an MP3 to sound, and I often wonder how they can throw so much of the audio signal away and for it to sound this good. There is no doubt these are low resolution recordings, but they are smooth sounding, relaxing and beautiful low resolution recordings. For me this is just further proof that good sound and high resolution are not one in the same. Low resolution formats can be made to sound good.

There is just something about computer music files that sounds so non-digital to me! In the past I speculated that part of what MP3s throw away is the part that makes CDs sound so bad to me. It is also possible I respond poorly to frequencies on CDs above 16kHz and/or artifacts above 20kHz as I discovered MP3s rolls off the highest frequencies, also bringing the audible frequencies further away from 44.1kHz's brick wall filter. My hearing extends to 24kHz and it is my feeling that it is something that CDs do in the upper frequencies that no other format does that makes them sound so objectionable to me and all the other thousands of people who do not like the sound of CD. That is why I find the upper frequencies usually sound extremely enjoyable on SACDs, high resolution downloads, LPs and Reel to Reel tapes but not on CDs.

MP3s are a mixed conundrum as on the one hand they are easier to listen to and usually don't have any of CD's gross sound deficiencies, on the other hand they do not have a lot of resolution or resolving power. The minimum acceptable bit rate for MP3s I have found is 192kbps VBR. For me MP3s work extremely well for background music when doing other things. When I sit down to "seriously" listen to music from my computer I turn to the 24 Bit 88.2 and 96kHz lossless downloads.

I keep my core audio on my Mac Mini at 24 Bit 96kHz and to my ears MP3s do sound better at this setting than at 44.1kHz. The Yamaha DVD-Audio/SACD player upsamples my CDs to 96kHz, still even though CDs are lossless I still enjoy the ultra-low resolution MP3s much more. I would not recommend MP3s for critical listening but for other times they may just be perfect, a lot may depend on your ears and your computer playback equipment. 

Summing up

1) I will be applying CD Stoplight to all my SACDs now and in the future, unless of course they are Green label SACDs.

2) I will not be buying any more CDs but may keep the dozen I've purchased as they do sound decent after applying CD Stoplight, excellent for background music and for reviews when I need to report on CD playback.

3) I will only purchase high resolution downloads at 24 Bit 88.2kHz or higher.

4) I will continue my MP3 subscription to eMusic.com for music not available in the high resolution formats as these MP3s are fine for noncritical listening, since I find them more enjoyable than even greened CDs, but I'm still not comfortable recommending them to others. These will be mostly used for discovering new music and new composers and to use as background music when working on the computer.

Remember nothing is written in stone, and it's a woman's prerogative to change her mind.  The most important thing is to enjoy the music in whatever form you listen to it in. If everything were released on SACD, I doubt I would be experimenting with all these other formats but such is not the real world.  I am so glad Sony started making Green label SACDs as it reintroduced me to CD Stoplight which has greatly improved my enjoyment of my SACD collection!