New to world of DACs, etc...need resources to learn the basics - diyAudio
Go Back   Home > Forums > Source & Line > Digital Line Level

Digital Line Level DACs, Digital Crossovers, Equalizers, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 1st March 2011, 02:50 PM   #1
diyAudio Member
 
jmillerdoc's Avatar
 
Join Date: Mar 2009
Location: Lawton, OK, USA
Default New to world of DACs, etc...need resources to learn the basics

Hi,
I am a virgin to DACs, well except for the built in ones in the various CDPs I have owned.

I recently purchased a nice Parasound CDP that has a digital out and would like to try using an external DAC...maybe even build my own. Problem os I know nothing about them and the various terms thrown around here...I.e. Clocks, IS2, toslink, spdif, etc...
I also have a nice Mac desktop that I understand can be turned into an awesome music server with the right gear connected.
I don't know where to start.....can anyone lead me to a good web article that explains all the basics so I can know where to start...I don't want to just start buying stuff and trying to make it work.

I did buy a DAC END2 kit a while back...I have populated all the boards and have everything to build it I think....I have put this on hold for now until I can learn a bit more about this stuff and hopefully what I have in this DAC END2.

Thanks a lot,
Signed,
Dacvirgin
  Reply With Quote
Old 2nd March 2011, 01:45 PM   #2
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
I can't direct you to a particular website, but things you need to know about include:
sampling theory and Nyquist limit, Fourier theory, anti-alias filters, reconstruction filters, digitisation, quantisation distortion, clock jitter, I/V converters.

Bear in mind that some of the people who put information on web sites don't understand the basics of digital sound nearly as well as they think they do, so don't believe everything you read. In particular, there is a lot of nonsense around about NOS DACs - these have a place, but many of their fans don't understand them. If you see a website which shows 'ringing' on a pure square wave 'produced' by an OS DAC, then ignore whatever it says as the author clearly does not understand Fourier and anti-alias filters.
  Reply With Quote
Old 3rd March 2011, 12:25 AM   #3
amc184 is offline amc184  New Zealand
diyAudio Member
 
amc184's Avatar
 
Join Date: May 2007
Location: Christchurch
DACs are a fun aspect of DIY Audio, and important given that most recorded music is sold in digital form. There aren't that many all encompassing articles on DAC design that I know of, but here are some suggestions for you:

- Don't solely focus on the choice of which DAC integrated circuit you will use. The S/P DIF receiver, digital filter, output stage and power supplies are just as important.
- Don't fall into the 'they don't make them like they used to' trap. There's a lot of sites out there claiming that nothing made later than the TDA1541A and PCM63 is worth using. Those are very good ICs, but there are newer ones that are better.
- Read up on existing projects. The threads on this forum are probably the best source of information there is.
  Reply With Quote
Old 3rd March 2011, 01:31 AM   #4
Banned
 
Join Date: Jan 2008
Blog Entries: 2
It may seem a bit odd to send you to TweakHeadz Lab Electronic Musician's Hangout, since it is a site about music recording, rather than playback, but although playback requires only a (stereo) DAC and recording requires both DACs and ADCs, which you'll find discussed under computer audio interfaces, there's a lot of relevant information there in one place, although you may want to skip over much of it. It's use-focussed too so there's a de-emphasis on the purely technical aspects, but it's by no means dumbed-down.

w
  Reply With Quote
Old 3rd March 2011, 01:49 AM   #5
diyAudio Member
 
jmillerdoc's Avatar
 
Join Date: Mar 2009
Location: Lawton, OK, USA
Can someone explain here the differences, pros, cons, applications of the different types of connections? I don't understand Toslink, SPDIF, IS2, etc....
My Parasound CDP has a digital out that looks just like an RCA Jack. The input of the DAC END2 has the same input.
I have a friend who has a Mac Mini he uses as a music server and he said what I need is a straight output like IS2 for this...I am confused about the different types of hook ups. What I would like to do is use my Mac as a music server and possibly use my Dac End2 as the DAC...I don't know what I need to do this....does the Mac have a digital out that I could somehow adapt to my Dac End 2 project?
Thanks,
Jeff
  Reply With Quote
Old 3rd March 2011, 02:07 AM   #6
amc184 is offline amc184  New Zealand
diyAudio Member
 
amc184's Avatar
 
Join Date: May 2007
Location: Christchurch
S/P DIF, or Sony / Philips Digital Interface Format is the single wire digital format used between transports and DACs. TOSLink is a way of carrying a S/P DIF format signal, it uses plastic fibre optics. S/P DIF is also commonly carried over coaxial cable terminated with RCA connectors. There is also a similar format used in professional applications that is carried by coaxial cable terminated with BNC connectors or shielded twisted pair cable terminated with XLR connectors.

I2S (pronounced I squared S, the 2 should be superscript), or inter-IC sound is an internal format used for short (>100mm) distances between ICs. This would be used between the S/P DIF receiver and digital filter, ore between the digital filter and DAC IC or similar applications. It is not intended to be used over significant distances, and isn't normally used to connect separate devices.

A Mac Mini will not have an I2S output. They have a mini TOSLink jack, shared for both digital and analog audio.
  Reply With Quote
Old 3rd March 2011, 03:27 AM   #7
diyAudio Member
 
jmillerdoc's Avatar
 
Join Date: Mar 2009
Location: Lawton, OK, USA
So, is the source of data from my Mac (regular Mac desktop) a good source? Do I need to put some sort of special sound card in the Mac to improve the source? The only outputs on the back of my Mac are USB....my DAC end then only has the SPDIF input.....can I easily add a Toslink input to the DAC End2? or, similarly, how can I get a digital signal mated from my Mac to my DAC End2 using it's existing SPDIF input?
Thanks, so far those info has been very helpful.
Jeff
  Reply With Quote
Old 3rd March 2011, 04:03 AM   #8
diyAudio Member
 
jmillerdoc's Avatar
 
Join Date: Mar 2009
Location: Lawton, OK, USA
This seems to be a very informative discourse....I have learned immensely from it, see the link below and let me know if those is the type of info I need to be understanding.

I2S: Is it a good external interconnect? Give your opinion and findings! | Computer Audiophile

Jeff
  Reply With Quote
Old 3rd March 2011, 04:45 AM   #9
amc184 is offline amc184  New Zealand
diyAudio Member
 
amc184's Avatar
 
Join Date: May 2007
Location: Christchurch
What sort of digital input your DAC unit will have is a decision you'll have to make. If you want it to be compatible with the majority of digital sources, then S/P DIF is your only choice.

I2S can be made to work, but you'll have to get a source that outputs it (there are some, but not many). The connectors and signal levels are proprietary for external I2S, so a DAC designed for a transport outputting I2S will likely be compatible with just that one transport.

USB and Firewire are also options for between a computer and DAC, but you're not going to be able to DIY a Firewire DAC, and any DIY USB DAC isn't going to be that great.

Quote:
So, is the source of data from my Mac (regular Mac desktop) a good source?
Probably not. What's a 'regular Mac desktop'?

Quote:
... how can I get a digital signal mated from my Mac to my DAC End2 using it's existing SPDIF input?
Exactly what digital audio outputs does your computer have?
  Reply With Quote
Old 3rd March 2011, 07:33 AM   #10
diyAudio Member
 
Join Date: Jun 2010
Location: St. Petersburg
imho Fourier has nothing to do with no PCM neither DSD.

Digitizing basically is a decimation process of an analog signal to series of discrete values that means information in between samples lost forever. The opposite process that is taking place in DACs is interpolation. That is very important to note. Because everything else like digital filters square waves etc are buzz words of technicians that has to perfect real hardware designs but some of them do not understand the basics of the ADC-DAC the interpolation stage in particular.

Once again ADC-DAC is decimation-interpolation no matter what buzzwords are used multibit singlebit Nyquest etc. That is why some audiophiles prefer analog LPs to digital (RedBook SACD etc) in order to eliminate interpolation and use original signal instead. And some manufactures like Wadia are developing custom "restoring" algorithms (decent RedBook playback imho).

Probably this is a nice place to start with DIY DAC
The Buffalo II Digital-to-Analog Converter

imho SACD player is the way to go nowadays.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Basics on transformer-coupling dacs ? intermittent Digital Line Level 16 26th May 2010 10:51 AM
resources jmillerdoc Solid State 5 9th April 2009 01:11 AM
Need to learn the basics ChaseMe Subwoofers 4 14th July 2005 02:18 PM
Help an ME learn the basics? 74Elsinore Everything Else 11 28th October 2004 06:59 AM
Audio DACs, Instrumentation DACs. Brian Guralnick Digital Source 10 3rd November 2002 05:56 PM


New To Site? Need Help?

All times are GMT. The time now is 10:21 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2