Ask questions to Audio insider Sir Terrence

[gearyt]

Originally Posted by jdc115

I believe M&K has now closed down or at least now any current speaker being sold is not from the original company but being manufactured by a Chinese company that bought over the name. About a year ago their website had a warning about purchasing their speakers due to them not be originals and now the site has been down for over 6 months just saying it is under construction.

I still enjoy a set I have from about 13 years ago

Love my m&k's but alas they did go under..
they liquidated and there are great deals on e-bay
the older model numbers are real m&k's
the name and spec's have been purchased and last time I looked the new site was coming up

whoops sorry. forgot what area I was in.. Thanks for all your expertise Sir T

[quetzalcoatl]

Originally Posted by Sir Terrence

I am just beginning to get my system together so that I can make the comparison, so my answer may not be based on sonics as much as getting everything off the disc that is there.

If extra value features are what you like, then the only way to go is to have the player do the decoding. If decoding Dts or DTHD in its native form, and avoiding transcoding to PCM is your goal, then bitstreaming to the receiver is the way to go. Extra's aside, their have to be some benefit both ways. To the player, they can be firmware upgraded so updates to encoding can be done at any time. Receivers are not easily updated, and I am not sure that any out there except the highest ends ones are updateable. Going to the receiver, it cannot be bad to skip extra transcoding and mixing stages of the decoding processes. I always believe that less is more when it comes to digital audio.

I cannot speak to any sonic benefits of either just yet, perhaps when I finish my research on receivers I want to get that do internal decoding and actually buy it(I just bought one 6 months ago), I can speak to sonic benefits with a little more information.

I am just curious how you go from this post to four days later saying receiver decoing is a marketing ploy? I am more than just abit confused Since I thought this post said there has to be some benefits both ways.

https://forum.blu-ray.com/showthread.php?t=32961

[Sir Terrence]

Originally Posted by quetzalcoatl

I am just curious how you go from this post to four days later saying receiver decoing is a marketing ploy? I am more than just abit confused Since I thought this post said there has to be some benefits both ways.

https://forum.blu-ray.com/showthread.php?t=32961

Its called additional research, and having the first answer be more off the cuff than actually educated. Once I looked at how the process truely works, it kind of made the first answer obsolete. That is what happens when you are constantly learning about anything. You feel one way in your ignorance, then you feel another once educated. Growth is a good thing, and so is educating your mind. The more I study this hobby, the more I learn. That is why I like to study.

[jdc115]

Originally Posted by Sir Terrence

Its called additional research, and having the first answer be more off the cuff than actually educated. Once I looked at how the process truely works, it kind of made the first answer obsolete. That is what happens when you are constantly learning about anything. You feel one way in your ignorance, then you feel another once educated. Growth is a good thing, and so is educating your mind. The more I study this hobby, the more I learn. That is why I like to study.

What about the possibility that PCM is subject to jitter but bitstream would not? I am not sure what the effects or what to listen for to be able to tell but at least that would be one thing that is different between the 2 methods?

Given the issue with room acoustics, what is your opinion of using a process like Audyssey? I am considering purchasing a NAD T175 processor once they work out a few of the current bugs and when it is available here.

[Sir Terrence]

Originally Posted by jdc115

What about the possibility that PCM is subject to jitter but bitstream would not? I am not sure what the effects or what to listen for to be able to tell but at least that would be one thing that is different between the 2 methods?

The question here would be, would you hear jitter? There are big questions on audible detection thresholds. Once again, the ambient noise level of a typical room would not facilitate any comparison of this kind to the ordinary user. Neither would the acoustics of the typical room. This would be a studio or lab kind of test because of the complexity of the measuring devices you would need to detect it, and the control on ambient levels. It is pretty useless for the ordinary consumer to worry about, as there is just no way to compare jittery and non jittery sound in real time. The amount of variables amoung the different equipment is pretty staggering, as we do not know the digital signal processing design. Without a way to hear both ways of decoding in real time(time differences in our auditory system are not friendly with delays in listening periods), no one can ever know if this is an issue. My opinion, you have alot of more audible things to worry about than this.

Given the issue with room acoustics, what is your opinion of using a process like Audyssey? I am considering purchasing a NAD T175 processor once they work out a few of the current bugs and when it is available here.

I am personally interested in Audyssey because it addresses some issues that the other systems does not. Its accuracy in receivers is still pretty questionable, but as a PC sourced application, it is extremely effective. I know I have had tested other computerized room correction schemes in receivers and found them to be uneven in their results. Imaging may improve, but the sound is too bright. Or its effectiveness in the deep bass is compromised. My eyes are on the Onkyo 705 to use as a pre-pro, and it has Audyssey room correction. Once I purchase it, I will see how it stands up against my trusty RTA and eq's to get my room right. Since my room is already acoustically treated for room modes and early reflections, it ought to be somewhat easier for the Audyssey to give me decent results.

[CAB]

Originally Posted by Sir Terrence

The question here would be, would you hear jitter?

In the example you were responding to, why would it matter what the framing was as jitter is a physical layer issue? Secondly, my understanding of HDMI is that there is a separate channel for clocking so it is less likely to have jitter (taking out the quality of the PLLs). Is my understanding of HDMI correct?

[quetzalcoatl]

Originally Posted by Sir Terrence

Its called additional research, and having the first answer be more off the cuff than actually educated. Once I looked at how the process truely works, it kind of made the first answer obsolete. That is what happens when you are constantly learning about anything. You feel one way in your ignorance, then you feel another once educated. Growth is a good thing, and so is educating your mind. The more I study this hobby, the more I learn. That is why I like to study.

NP I was just asking since it seemed like a very quick change and I thought maybe I was not reading it right.

[Sir Terrence]

Originally Posted by CAB

In the example you were responding to, why would it matter what the framing was as jitter is a physical layer issue? Secondly, my understanding of HDMI is that there is a separate channel for clocking so it is less likely to have jitter (taking out the quality of the PLLs). Is my understanding of HDMI correct?

My understanding of jitter and how it relates to HDMI is in the area of cable length. While I am not aware of a seperate channel for clocking, I would think if that is an issue to you,(A) keep your cable runs very short, or (B) use a HDMI 1.3A aftermarket signal booster that has internal clocking within the processing and(C) choose good cables in the first place. IMO that would erase any benefit that bitstream would have over PCM using HDMI, and I would think at short cable runs it would be a non issue anyway. I would think that any digital audio product designed for decent quality sound would reclock the data just before D/A conversion, and guess I assumed that most did. This is really the last stage you can correct jitter. If that is the case in receivers, then it is benefitting both bitstream and player decoding equally, as that is the last stage of conversion anyway.

[Brandon B]

Out of curiosity, since you have all the outboard amps, why would you choose the Onkyo 705 receiver over the Onkyo Pro 885 pre pro? Are you using the receiver amp channels as well?

BB

[Sir Terrence]

Originally Posted by Brandon B

Out of curiosity, since you have all the outboard amps, why would you choose the Onkyo 705 receiver over the Onkyo Pro 885 pre pro? Are you using the receiver amp channels as well?

BB

Brandon,
It has never been my plan to keep a receiver as my pre-pro. When I was looking for a HDMI receiver that was able to pass audio as well as video, this was one of the few that was out there. My other reason was I didn't want to spend big money just yet, and going the receiver route represented a cheap more economical way for a temporary upgrade. I have been looking very closely at the 885, but I have also been looking at other simularly equipt pre-pro. I am not in a hurry to make any changes at this point though, because what I have currently is suiting my needs just fine.

[DaViD Boulet]

The question here would be, would you hear jitter? There are big questions on audible detection thresholds. Once again, the ambient noise level of a typical room would not facilitate any comparison of this kind to the ordinary user. Neither would the acoustics of the typical room.

as a listener who has heard quite audible differences between transports and digital cables feeding the same (red book CD) bit-data to the same outboard d/a converter, I'd respectfully disagree.

But minor differences aside, it's a pleasure and indeed a bit of a thrill to find a serious audiophile like yourself here on our forum. Welcome!!!

dave

[dialog_gvf]

> Customized Toshiba 65H84 RPTV 9" tubes

Do tell.

[Sir Terrence]

Originally Posted by DaViD Boulet

as a listener who has heard quite audible differences between transports and digital cables feeding the same (red book CD) bit-data to the same outboard d/a converter, I'd respectfully disagree.

But minor differences aside, it's a pleasure and indeed a bit of a thrill to find a serious audiophile like yourself here on our forum. Welcome!!!

dave

The question I have for you David is can you attribute the differences you heard squarly to jitter, or where the devices just better built with better quality components?

[Sir Terrence]

Originally Posted by dialog_gvf

> Customized Toshiba 65H84 RPTV 9" tubes

Do tell.

I have a couple of buddies who went to college with me who is a CRT geniuses. They seem to know everything under the sun about display devices, but have a particular love for CRT based RPTV's and projectors. They essentilly cored out the Toshiba, and upgraded it with a better screen, and three high quality all electromagnetic focused 9" CRT's. The television itself has no internal speakers anymore(had to make room they say), and all processing is handled via outboard video processor. The lenses are double focused, and color pure. The only thing the television does is D/A conversion. With the outboard processing, to say you get a good picture is a understatement to infinity.

[DaViD Boulet]

The question I have for you David is can you attribute the differences you heard squarly to jitter, or where the devices just better built with better quality components?

Since the same digital bit-for-bit data was being converted to analog on the same outboard d/a converter in these cases (everything else in the system downstream from and including the d/a converter was the same), the only differences were the disc transport and digital cables and therefore any audible differences would, by definition, be jitter-related. (bit-for-bit identical data: no DSP processing was applied).

Just a quick note: my first time hearing "jitter" was when making digital dubs of my DAT tapes on two TASCAM DA-30 DAT Decks. I noticed that the dubs made with digital coax sounded flatter and harsher than the original DAT tapes, and that the digital dubs made with XLR balanced digital cables sounded identical to the original tape. I called TASCAM to talk to a technician there to figure out what was wrong since "bits are bits" and both the copy and the source should have sounded the same in all cases. He said "oh yeah, you also have sub-code data mixed in with the digital audio signal in the SPDIF coax carrier, and that can cause inaccuracies in the time-clock signal which can degrade the sound slightly during playback". It was the first time I ever heard jitter... and I heard it before I even knew the term or had ever heard anything to suggest that it was possible for bit-for-bit data to be affected by time-domain characteristics of the time-clock during d/a conversion.

[Sir Terrence]

Originally Posted by DaViD Boulet

Since the same digital bit-for-bit data was being converted to analog on the same outboard d/a converter in these cases (everything else in the system downstream from and including the d/a converter was the same), the only differences were the disc transport and digital cables and therefore any audible differences would, by definition, be jitter-related. (bit-for-bit identical data: no DSP processing was applied).

Just a quick note: my first time hearing "jitter" was when making digital dubs of my DAT tapes on two TASCAM DA-30 DAT Decks. I noticed that the dubs made with digital coax sounded flatter and harsher than the original DAT tapes, and that the digital dubs made with XLR balanced digital cables sounded identical to the original tape. I called TASCAM to talk to a technician there to figure out what was wrong since "bits are bits" and both the copy and the source should have sounded the same in all cases. He said "oh yeah, you also have sub-code data mixed in with the digital audio signal in the SPDIF coax carrier, and that can cause inaccuracies in the time-clock signal which can degrade the sound slightly during playback". It was the first time I ever heard jitter... and I heard it before I even knew the term or had ever heard anything to suggest that it was possible for bit-for-bit data to be affected by time-domain characteristics of the time-clock during d/a conversion.

I have heard of this, especially coming from SPDIF based input/outputs.

IMO the jury is still out on this via HDMI

This is why I stated this kind of comparison belongs in the studio or lab. Ordinary consumers would not have access to comparative material that is highly controlled in production.

[DaViD Boulet]

Yes, jitter over HDMI may be a different animal or a less significant (less audible) issue versus SPDIF.

In the SPDIF protocol, the analog time-clock signal is buried in with the digital audio data and is subject to all the problems that any analog signal would be: cable reflections etc.

I think with HDMI they may have designed a better architecture: possibly keeping the time-code on a discrete carrier or developing a better way of isolating any time-clock error versus what we had to deal with in SPDIF signals. I'm not too familiar with the technical details of HDMI so I can't comment further, but look forward to getting more familiar with this new standard when I get time.

[dialog_gvf]

Originally Posted by Sir Terrence

I have a couple of buddies who went to college with me who is a CRT geniuses. They seem to know everything under the sun about display devices, but have a particular love for CRT based RPTV's and projectors. They essentilly cored out the Toshiba, and upgraded it with a better screen, and three high quality all electromagnetic focused 9" CRT's. The television itself has no internal speakers anymore(had to make room they say), and all processing is handled via outboard video processor. The lenses are double focused, and color pure. The only thing the television does is D/A conversion. With the outboard processing, to say you get a good picture is a understatement to infinity.

Damn, I'm jealous. I have a 57HDX82 that a local calibrator manages to whip into amazing convergence and a beautiful flat gray scale.

Have you ever done a resolution test? Can you get a full 1920 horizontal?

Gary

[Sir Terrence]

Originally Posted by dialog_gvf

Damn, I'm jealous. I have a 57HDX82 that a local calibrator manages to whip into amazing convergence and a beautiful flat gray scale.

Have you ever done a resolution test? Can you get a full 1920 horizontal?

Gary

They did do a resolution test, and I was able to get full 1920 horizontal. They say it should be able to do full 1440p, but I have nothing to test that. When they discribe all of the technology that went into this set, It makes my head spin.

[dobyblue]

Sir and David, would either of you know the following?

DSD1792 DAC I believe is being used in the Yamaha RX-V3800 receiver.
Is this DAC capable of full DSD to analog conversion?

I don't see anywhere in the chip specifications where it lists a clock speed as high as DSD needs for full conversion.

The only chip I see that has a clock speed of DSD is the DSD1700, which has a clock speed of 11.2896 Mhz (256 * 44.1kHz) and a data clock of 2.8224 MHz (64 * 44.1kHz)

http://www.datasheetcatalog.com/data.../DSD1700.shtml

http://www.datasheetcatalog.com/data.../DSD1792.shtml

If the DSD1792 is not capable of a data clock speed of 2.8224 MHz but still can convert DSD to analog without hitting the PCM realm when the receiver is in "DSD DIRECT" mode, how does it acheive it?

The Denon and Onkyo receivers both claim they don't do PCM conversion in certain direct modes as well and I believe the Denon 4308CI and Onkyo TX-NR905 are both using the PCM1796 DAC.