Digital, but not by the numbers

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
umm another dirty secret, the computer is ALWAYS doing other things than playing music when playing music.


So true, but we are at the point where we can't take the computer out of the equation (as I stair at a wall of CD's I need to rip) :wchair:

And nothing new under the sun... There was the MUTRAN program/language that ran on an IBM 1620 in the 60's that produced music by precisely timed program loops that caused enough RF noise that you could pick it up on an AM radio placed close to the mainframe computer. Was that perhaps the first wireless computer audio? No DAC to be seen anywhere.

I agree with what you are saying but the new NAD 51 is really the first commercial application I have seen.

Times are changing and moving fast I can't say to what but I know its a really bad time to invest a lot of time or money in a DAC, I can almost guarantee that. Let's face it HDMI is here to stay, majority of folks aren't using USB or SPDIF, they are using HDMI its just too convenient.

Its a fascinating discussion no matter how you look at it.
 
Last edited:
So true, but we are at the point where we can't take the computer out of the equation (as I stair at a wall of CD's I need to rip)

And what is a computer anyway. Your average CD player is full of logic circuits and has at least a couple of CPUs...

Times are changing and moving fast I can't say to what but I know its a really bad time to invest a lot of time or money in a DAC, I can almost guarantee that. Let's face it HDMI is here to stay, majority of folks aren't using USB or SPDIF, they are using HDMI its just too convenient.

But HDMI is probably a brief transition phase too. My bet is on IP-based solutions - no point in having a DAC without network player functionality included. And that kind of takes your "computer" (as in a general-purpose PC/Mac/whatever) out of the picture again.
 
So true, but we are at the point where we can't take the computer out of the equation (as I stair at a wall of CD's I need to rip) :wchair:



I agree with what you are saying but the new NAD 51 is really the first commercial application I have seen.

Times are changing and moving fast I can't say to what but I know its a really bad time to invest a lot of time or money in a DAC, I can almost guarantee that. Let's face it HDMI is here to stay, majority of folks aren't using USB or SPDIF, they are using HDMI its just too convenient.

Its a fascinating discussion no matter how you look at it.

agreed its interesting, personally I dont see the fast switching as such a buggaboo, the benefits outweigh the issues and the issues can be dealt with far easier at high speeds, as long as the audio systems are isolated from the power supply and ground that must supply all that transient disarray
 
exactly but then what to do about that orgy of horribly fast ethernet/wifi/bluetooth glitching haha. regardless thats where my efforts are focused.

When I look at the history of high end audio it always follows theater. The whole 300B tube renaissance we had the last decade was from top WE engineers working in the 20's-30's to give the theater experience, then the Altec Lansing Horns, etc.

Now of course its home theater, I guess I just see us stuck with HDMI. But if 10/100 gigabit Ethernet works out that would probably be the best for everyone, its exciting times. But I'm still of the opinion that the Intel PC/Mac will be the center of it all, I mean I didn't have to upgrade my 5 year old Maranz HDMI 1.1 receiver because my computer can decode any hirez blue-ray audio format and send it as LPCM, its so flexible
 
oh sure, i'm not saying the computer will be released from duty, it'll still do most processing at least for the short term, just that it wont necessarily be physically connected to the audio hardware. I made the above comment about glitching extreme enough in the hope that it would be recognized as tongue in cheek :)
 
"digital" is getting to the point where it is "analog". Dirty secret is it always has been, digital only exists in books, even our computers are nothing more than billions of analog signals switched on or off with transistors.
Digital also exists as a seperate engineering disipline, you dont design digital the same way as you do analogue, especially PCB layout. A while the transistors are switching, they are either on or off, there is no intermediate steps, unlike analogue where you can have varying voltages, the voltages is either one or another voltage representing 0 or 1.
So while digital has analogue elements you have to employ digital design techniques when you are designing digital circuitry, and with todays signal rise times more often than not you have to use high speed digital design techniques. (of course to confuse matters a bit we use S parameters in high speed signal verification software:)).
Bluetooth design and layout is a PIFA:D:D Pun intended!
 
Digital also exists as a seperate engineering disipline, you dont design digital the same way as you do analogue, especially PCB layout. A while the transistors are switching, they are either on or off, there is no intermediate steps, unlike analogue where you can have varying voltages, the voltages is either one or another voltage representing 0 or 1.
So while digital has analogue elements you have to employ digital design techniques when you are designing digital circuitry, and with todays signal rise times more often than not you have to use high speed digital design techniques. (of course to confuse matters a bit we use S parameters in high speed signal verification software:)).
Bluetooth design and layout is a PIFA:D:D Pun intended!

I agree that digital is a separate engineering discipline that requires different design techniques but we can't dismiss materials science and thermodynamics with engineering approximations, ie infinity is an abstraction (no square waves can exist, they are an singularity.) To an digital design engineer a transistor is a switch, but talk to a materials engineer or even an good RFI EE and you will get a different answer.

That's the fun part of engineering, looking at the fundamental laws of physics and realizing we engineers don't have all the answers and neither do scientists :eek:.
 
Hi Regal,
the higher the frequencies and faster rise times the moreanalogue problems you have, the main one being the higher harmonics.
Yes a true square wave is an impossibility, and these days with DDR memory interfaces, the waves when viewed on a scope look more like sharkfins than a square wave.
Intrestingly, with the ever increasing embedded processing involved with even the most mundane electronic equipement these days, one has to wonder how much if any effect firmware could have on audio quality :) A simple thing would be FPGA and similar based designs, lowering the rise times and thus switching currents can help with the overall system noise floor.
One of the problems with consumer based digital gear is cost of manufacture, quite often compramisers are made (especialy with layout, mainly layer counts), these often add to system noise. One would hope that high end digital equipement has proper multilayer boards (12-14), which is what PC's should have as a minimum, a lot dont though.
As to bluetooth, its becoming popular for remote controls, that should add a bit more noise to the EMC spectrum, off course if you use power line communications you'll have plenty of noise around before you even plug in anything else.
I look at5 the elctrical noise like light polution, when I was young I could see the stars, and if I pluged myself into a scope, I could see a 50Hz sine, now If I lkook at the sky I can see a couple of stars, and when I plug myself into a scope...noise.
My favorite time to listen to music these days is late at night, when all are in bed, no network, no TV,s, little background noise both electrical and airborne, bliss. Whether it affect the sound I cant say, or measure, I havn't the kit, but mentally it always sounds better to me.
 
Hi Regal,
the higher the frequencies and faster rise times the moreanalogue problems you have, the main one being the higher harmonics.
Yes a true square wave is an impossibility, and these days with DDR memory interfaces, the waves when viewed on a scope look more like sharkfins than a square wave.
Intrestingly, with the ever increasing embedded processing involved with even the most mundane electronic equipement these days, one has to wonder how much if any effect firmware could have on audio quality :) A simple thing would be FPGA and similar based designs, lowering the rise times and thus switching currents can help with the overall system noise floor.
One of the problems with consumer based digital gear is cost of manufacture, quite often compramisers are made (especialy with layout, mainly layer counts), these often add to system noise. One would hope that high end digital equipement has proper multilayer boards (12-14), which is what PC's should have as a minimum, a lot dont though.
As to bluetooth, its becoming popular for remote controls, that should add a bit more noise to the EMC spectrum, off course if you use power line communications you'll have plenty of noise around before you even plug in anything else.
I look at5 the elctrical noise like light polution, when I was young I could see the stars, and if I pluged myself into a scope, I could see a 50Hz sine, now If I lkook at the sky I can see a couple of stars, and when I plug myself into a scope...noise.
My favorite time to listen to music these days is late at night, when all are in bed, no network, no TV,s, little background noise both electrical and airborne, bliss. Whether it affect the sound I cant say, or measure, I havn't the kit, but mentally it always sounds better to me.

Thankyou, digital design is really fascinatingly complex a 12-14 layer PCB is mind blowing to me ! I am heading back to the tube forum :sax:
 
For the serious audiophile, I present:
The Ultimate Semiconductorless Sound


:D:D:D
 

Attachments

  • gramophones_picbig_hmv_7.jpg
    gramophones_picbig_hmv_7.jpg
    48.7 KB · Views: 72
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.