SACD Passed me by, Until Now (Updated)

Back in the day I knew about DSD (Direct Stream Digital) and SACD (Super Audio CD) but it passed me by. I was still in Burr-Brown when DSD data converter ICs were first being developed by the design team in Japan, and I'm sure I was present when they were being presented at seminars to customers, but at the time I had little or no interest in diving in personally. Burr-Brown invested heavily in designing ICs for the upcoming market demand, but as history tells us, it didn't become mainstream. Certainly not in the US, less so in Europe, but in Japan there was always demand.

Philips and Sony originally developed SACD as the high end next generation of CD, and certainly the format was capable of encoding a significantly higher level of audio information on the platform. DSD was a delta-sigma bitstream format that sampled 1-bit at 2.8MHz. Philips Semiconductors (amongst others) developed an SACD processor and Burr-Brown (amongst others) developed DSD Digital to Analog converters.

Late to the party, but not wanting to invest significantly in a new SACD player (yes you can get them), or even used ones (they can also be very expensive to buy), I started looking at DVD players that could play SACDs. For only £35 I picked up a Pioneer player from the 2000s which used a Philips SAA7893HL SACD processor, one Burr-Brown DSD1791 24-bit stereo D/A converter and two DSD1702 24-bit stereo D/A converters. I believe it was one of only a few DVD players from Pioneer that played SACDs.



The player can output 2 channel audio and 5.1 surround sound audio. The higher spec DSD1791 was used for the Left and Right channels and the lower spec and less capable DSD1702s for the surround, centre and sub-woofer channels. Looking at some recent implementations of SACD players, the TI DSD1793 is being designed today into SACD players, and has identical specs to the DSD1791. Released later, it may be a redesigned lower manufacturing cost version.




SACD has a theoretical dynamic range up to 120dB and an extendend frequency response up to 100kHz. In practical terms, it is lower. The Pioneer DV-565A I've bought has a DR of 108dB, an SNR (signal to noise ratio) of 118dB and a THD (total harmonic distortion) spec of 0.0014%. Really very impressive for a player. The DSD1791's DR is 113dB with a THD+N (plus noise) figure of 0.001%. The lower spec DSD1702 used for the other channels has a DR of 106dB. Although not specified, the player's dynamic range may be for the L+R channels only.

As yet I've not listened to any SACDs, just waiting for some to arrive, so will update the blog once I hear them.

Update :

I bought six SACDs from Discogs, two of them hybrid SACD/CD. The first to arrive was John Coltrane A Love Supreme. I do have this record in quite a few variants and formats including a 1st US pressing stereo vinyl. With great anticipation I listened to the SACD. It was a disappointment compared to the CD versions I own. Very soft, and clearly a different mix however. Switching between the SACD and the CDs on my Denon CD player is not a true comparison, but the Denon sounds better for sure. The SACD is a Rudy Van Gelder remix specifically for SACD and I don't like it. He's chosen to reduce McCoy Tyner on piano and it doesn't do it for me. Elvin Jones hard right is a little bit more prominent but Trane's sound on the left channel is a little bit meh. Access to the original master tapes was non existent for many years - they were disposed of way back, and the best copies had flaws. It was only after the original British HMV vinyl pressing master was found at Abbey Road studios that we've been able to obtain decent reissues. So perhaps not the best record for a comparison.

I also bought three London Symphony Orchestra (LSO) Live SACDs, recorded live directly into DSD. Steve Reich, Rachmaninov, Stravinsky and James MacMillan. The first I played was the Rachmaninov Symphonic Dances conducted by Valery Gergiev. What hit me with this SACD was the dynamic range, and at the lower end (if that makes sense ?). My hearing is unlikely to distinguish high frequency dynamic range differences, but at lower frequencies, yes. Definitely a bit of a wow. Unfortunately I can't compare with CD, but I do have a lot of classical CDs. So again no definitive better or not, but I would say there is something extra there with the SACDs.

The two hybrid SACD/CD discs are a pop one - Sting and a classical one - Elliott Carter. Unfortunately I can't figure out how to get the Pioneer to play the CD layer and the SACD, rather than just the default SACD. When I compare the SACD to the CD played on my Denon CD player, I prefer the Denon on both. The Denon has two PCM1702s, which are 20 bit R2R ladder DACS - two 19 bit DACs in a complementary design, an improved version of the PCM63P. So perhaps this is a top end audio R2R ladder DAC versus a top end Bitstream one and I prefer the R2R ladder one.






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