Dvd-audio & sacd are true multichannel formats: a DSP is NOT the same thing! (1 Viewer)

[Shawn Fogg]

Craig,

No problem. For stereo music a very dead room will tend to sound lifeless and flat and it will highlight the 'looking through a window' experience. The rooms 'sound' is needed for 2 channel to help with the above. That is why I suggested taking your speakers outside and listening to them for awhile. The experience will sound very different then what you are accustomed to. As has been mentioned the live end dead end is what is usually recommended for stereo listening.

When you use surround (either discrete or derived) you have the surrounds (and 4 are better then 2 here) playing back the halls sound. So in this case an overall dead room is a good thing.

Shawn

 

[Lee Scoggins]

I found the experience with Trifield very eye opening

I agree with John on this. When we have done trifield at Chesky Records and used ambiance only in the rear channels, my ears tell me that we get the best result.

The problem with 5.1 is that height-based information is often lacking, which is why David went to 6.0 to add two upper speakers.

The thing about this is it is a philosophical debate as much as anything. Here are three observations from 20 years in audio.

1. Like Walter Becker of Steely Dan fame says, I don't want to be on the stage, I want to be listening from Row N or so (at least H).

2. Really good 2 channel sounds awesome and creates an enveloping soundfield and is usually under-rated these days.

3. Many great old recordings were done in Trifield. The best way to present these is add ambiance (room tone where available to the rears) and leave L-C-R the hell alone, sit back and enjoy.

 

[Cliff Olson]

What do you guys do when an SACD is recorded in 2-channel only? Do you have your pre/pro convert it to PCM and use the DSP?

 

[Bill Lucas]

Sorry to jump in so late but I find this thread quite interesting.

Kevin,

There's a major flaw in your first point back on page 2. When you think about it you *may* change your thinking a *bit*.

When you go to a concert hall all of the artists are in front of you. This is absolutely correct. What you failed to say is that unless you are in one of a few choice seats in the concert hall that nearly all of the sound that comes to your ears is reflected information. It is the recreation of this reflected sound and the startling accuracy with which the recreation is done that sets Meridians Trifield and Lexicons Logic 7 apart from the rest. Trifield is also very setup intensive and done right it lends itself to nearly any type of recording. Done incorrectly it's the most bastardized thing you've ever heard. Regards.

 

[Lewis Besze]

What do you guys do when an SACD is recorded in 2-channel only? Do you have your pre/pro convert it to PCM and use the DSP?

No we stock with it,and hoping that the up coming DVD-A will correct this oversight.

 

[Brett DiMichele]

You know what guys?

Just forget this 2 Channel Vs. Multichannel. Just buy Bose
Direct Reflecting Speakers and you will all be in 7th Heaven...




And that is all I have to say!

 

[John Kotches]

Cliff Olson asked:

What do you guys do when an SACD is recorded in 2-channel only? Do you have your pre/pro convert it to PCM and use the DSP?

Absolutely. It's no different from any other high quality 2 channel source, and especially when we're talking Meridian, the A/D is (for all I can tell) transparent.

I suspect that an 861 with 24/96K A/D on analog inputs would be even better.

Regards,

 

[Shawn Fogg]

Brett,

"Just forget this 2 Channel Vs. Multichannel. Just buy Bose
Direct Reflecting Speakers and you will all be in 7th Heaven..."

I know you meant this in jest but since you are a AR nut have you ever looked into the AR 'Magic' speaker? You might want to read up on what it did and why it did it.....

Shawn

 

[Phil_DC]

Cliff Olson

Absolutely. It's no different from any other high quality 2 channel source, and especially when we're talking Meridian, the A/D is (for all I can tell) transparent.

That does not work, at least for my setup; The Pioneer 47Ai has 5.1 channel analog outs and a separate 2 channel analog outs. The 2 channel SACD goes out via the LT and RT front outs in the 5.1 out area so you can't use any DSP.

Maybe there is a way to force 2 channel SACD through the regular LT & RT analog outs then DSP would be doable. I think I will have to play around with it this weekend an see.

 

[Cliff Olson]

That does not work, at least for my setup; The Pioneer 47Ai has 5.1 channel analog outs and a separate 2 channel analog outs. The 2 channel SACD goes out via the LT and RT front outs in the 5.1 out area so you can't use any DSP.

I know you can use the DSP on Lexicon pre/pros, I'm not sure about Meridian though. I have been experimenting with the "Music Logic" surround mode lately with SACDs. I have a DC-1, so I can't do 5.1 until I upgrade.

It sounds pretty good (still better than redbook), even though the Lex is down-converting the DSD signal. The resolution and dynamic range is still higher than that of redbook CDs, IMO. What are your thoughts, Shawn? What kind of loss do you hear in your system, if any?

 

[Shawn Fogg]

Cliff,

" It sounds pretty good (still better than redbook), even though the Lex is down-converting the DSD signal."

By the time the Lexicon sees the signal it isn't DSD... it is analog. From there the Lexicon is converting the analog signal to PCM to let it apply processing. For two channel SACD any pre-pro can redigitize the signal since it treats it the same as any other two channel analog input.

"The resolution and dynamic range is still higher than that of redbook CDs, IMO."

What is the serial number of your DC-1? If it is below around 7800 it is using 16bit A/D converter and it samples at 44.1kHz. IOW, it converts an analog signal to that of a redbook CD. Having said that I'd still do this too to take advantage of Music Logic. If it is a later DC-1 it would have 20bit A/Ds.

"What are your thoughts, Shawn?"

I redigitize them (including 5.1) because in my system the benefits of time alignment, bass management and additonal processing far outweigh the very slight potential for loss, the MC-12 A/Ds at 96/24. It simply sounds more coherent using this method.

Shawn

 

[Cliff Olson]

I know it's a later model with the 24-bit DACs. I'll check on the serial for A/D conversion...

 

[Shawn Fogg]

Cliff,

If it has the 24bit DACs then it also has the 20bit A/Ds. They were both upgraded at the same time.

Shawn

 

[Cliff Olson]

The serial number is "L05988042", so can I assume that it is using 20-bit A/D?

Just read the above post, sorry...

 

[John Kotches]

Cliff said:

I know you can use the DSP on Lexicon pre/pros, I'm not sure about Meridian though. I have been experimenting with the "Music Logic" surround mode lately with SACDs. I have a DC-1, so I can't do 5.1 until I upgrade.

Meridians processors are "fully digital". All analog inputs are A/Dd (24/48K in the 568.2, up to 24/96K in the 861 depending on card selection). From there, it's JADS (Just Another Digital Source. Analog in is limited to stereo on

The only aspect of Meridian processors that isn't "fully digital" are the analog outputs. Here Meridian uses an hybrid volume control, digital up to the point where 24bits resolution would be impacted and analog from there.

Regards,

 

[Cliff Olson]

By the time the Lexicon sees the signal it isn't DSD... it is analog. From there the Lexicon is converting the analog signal to PCM to let it apply processing.

Does anyone know the resolution of SACD analog signal (ie. 24/192k)?

 

[Rich Malloy]

Cliff, you'll need to hear from someone more technically knowledgeable than I, but DSD and PCM are significantly different in this respect. DSD converts an audio waveform to a 1-bit representation using a 2.8224MHz sampling frequency.

Transforming DSD signals to PCM degrades the signal. This is why Lexicon owners have created their own DIY "analog bypass" path, as described by Shawn Fogg here: http://www.smr-home-theatre.org/Lexicon/mc1/bypass.html

 

[Rich Malloy]

I should say "some" Lexicon owners use the bypass Shawn describes, but from your statements here, I guess you don't do this, Shawn?

I redigitize them (including 5.1) because in my system the benefits of time alignment, bass management and additonal processing far outweigh the very slight potential for loss, the MC-12 A/Ds at 96/24. It simply sounds more coherent using this method.

I've hooked up my SACD player to the "redigitizing" inputs of my receiver, and the degradation of sound quality is not slight. It still sounds good, of course, but it's quite noticeable. So, I always and without fail pass the DSD-derived analog signal through my system without further digital processing.

I handle time alignment the old-fashioned way... equidistant placement of speakers (it needn't be to the last millimeter), and I use the Outlaw ICBM-1 for bass management. The only issue that might be problematic (but fortunately isn't for me) is setting levels equally for all channels. My Sony C555ES SACD player allows for level-setting if I engage the bass management circuitry, but engaging that circuitry comes at the expense of a rather severe degradation of sound quality. Since my levels are "close enough", and overall sounds heaps better than having to send the signal through the onboard processer, this is where I've chosen to make the compromise.

(Exact level matching would have me raise the rears a tad and the center a tad less, as tested with Radio Shack SPL meter. However, I found that when listening to the "proper" level-matched setting, the playback of the rear channels is at a subjectively too high level for me. So, this compromise is, for me, more in line with my preferred listening setup.)

 

[Shawn Fogg]

Cliff,

"Does anyone know the resolution of SACD analog signal (ie. 24/192k)?"

It doesn't translate to PCM numbers very easily. Because with DSD as the frequency goes up the resolution (noise floor) goes down. PCM keeps the noise floor the same over the entire bandwidth of the signal.

Rich,

" but from your statements here, I guess you don't do this, Shawn?"

Nope, I built it to see if it would work. The first thing I tested was a level matched comparison of a source in analog bypass through my old MC-1 vs. going through the A/D-D/A stages with no processing. I couldn't tell them apart so at that point I went with the A/D to allow for all the benefits of processing. I do know a few guys using that setup though and like it from a purist standpoint which is cool too.

On the MC-12 for both two channel and 5.1 sources the user has their option of analog bypass or using the A/Ds to allow processing. Some like it one way some like it the other. In my system it sounds considerably better using the processing.

" I've hooked up my SACD player to the "redigitizing" inputs of my receiver, and the degradation of sound quality is not slight. It still sounds good, of course, but it's quite noticeable."

Have you level matched (to 0.1dB) the two when you compared them? Usually going through the A/D-D/A will drop the level down a couple of dB which in direct comparison against a bypass will not sound as good. But that is a levels thing.

Shawn

 

[Rich Malloy]

Shawn, I'm not sure if I've leveled matched to .1db, but it hits the same mark on my analog Rat Shack meter. I think the difference may well be that your Lexicon (or Meridian) simply does the conversion much more transparently.

FWIW, I also prefer to "analog bypass" my CD sources, too. I guess my budget receiver simply isn't a very transparent processor (Outlaw 1050), or at least not as good as the DAC in my Sony C555ES, as I lose an unacceptable degree of "realism" in the playback. Mostly the leading edges and the decay of the sound are muted and shortened, respectively, and the timbres don't strike me as being quite as true. When one graduates up to a Meridian/Lexicon level of processing, I'd imagine this is much less an issue.