Hi Nick,
Looking great! I am now back and gagging to get started with my CoolRunner II kit! (I got well caned for postage and then import duties though, there's something rotten in the system I think. A bill of £20 for tax and fees for an order amounting to $50. ) I do hope we can buy the bare CPLD locally and save this rampant highway robbery from FedEx.
I'm not sure where to start, I've got a big learning curve to climb before I can catch up to you and start testing against the SB3.
Cheers,
Tony
FAO Tony Moore
#17
Step one, get the software on a PC, then write some simple vhdl, Andrew is the man for info on the language, and I will try and help with the stuff that relates to the board.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
#18
Happy to help Tony, might be better if we do it by e-mail rather than boring everyone.
Aren't import duties a rip-off, its the handling charges that are the killer for small items as they are fixed fee, VAT I guess I can live with, its the law of the land, after all.
Nick found a free 'guide' that I looked at and though was reasonable reading....Nick what was that link?
cheers,
-- Andrew
Aren't import duties a rip-off, its the handling charges that are the killer for small items as they are fixed fee, VAT I guess I can live with, its the law of the land, after all.
Nick found a free 'guide' that I looked at and though was reasonable reading....Nick what was that link?
cheers,
-- Andrew
#19
The totorial I found before has moved from the Wiki entry, but this looks a good place
http://members.optushome.com.au/jekent/ ... m#Section1
http://members.optushome.com.au/jekent/ ... m#Section1
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
-
Tony Moore
- Old Hand
- Posts: 499
- Joined: Thu Aug 02, 2007 12:24 am
- Location: New Brighton
#20 Update
Hi All,
Well, an update is called for! I successfully got the CoolRunner II development board to convert the SB3 output to standard I2S and drive my TDA1541A based DAC. Thanks to Nick and Andrew for help on the VHDL coding. The code I'm using is only rough at the moment and I will update it to a more comprehensive version as I learn more and as the "Design group" suggests improvements. It does the job at the moment though and allows me to experiment.
Al came over to my house today and we did a short A/B listening test between the S/PDif connection and the I2S. I think Al will agree that what we heard was quite a marked improvement in imaging and clarity with the I2S over the S/PDif. Instruments seemed to become more distinct and attack on notes more realistic. I'm not very good at describing the things I hear, perhaps Al could add his comments?
Anyway, it's certainly confirmed to me that it is worth doing and I am now going to remove my synch reclocking mod and go direct to the TDA1541A from the CPLD and see if that sounds any better or worse. I would like to try to reduce the complexity of my DAC but also have a technically better solution.
Cheers,
Tony
ps Update update:
I have now tried the I2S straight from the CPLD dev board straight into the TDA1541A using 3" of ribbon cable. (Not ideal) Sound is different once again, plus my timing issue with the WCLK is now fixed so it _was_ due to the reclocking. I feel the sound is now more mellow and relaxed, not so "in your face". I will be calling on Al's ears again (with his continued patience!) though I think to help me do an A/B test and help me come to a conclusion on which is "best".
Well, an update is called for! I successfully got the CoolRunner II development board to convert the SB3 output to standard I2S and drive my TDA1541A based DAC. Thanks to Nick and Andrew for help on the VHDL coding. The code I'm using is only rough at the moment and I will update it to a more comprehensive version as I learn more and as the "Design group" suggests improvements. It does the job at the moment though and allows me to experiment.
Al came over to my house today and we did a short A/B listening test between the S/PDif connection and the I2S. I think Al will agree that what we heard was quite a marked improvement in imaging and clarity with the I2S over the S/PDif. Instruments seemed to become more distinct and attack on notes more realistic. I'm not very good at describing the things I hear, perhaps Al could add his comments?
Anyway, it's certainly confirmed to me that it is worth doing and I am now going to remove my synch reclocking mod and go direct to the TDA1541A from the CPLD and see if that sounds any better or worse. I would like to try to reduce the complexity of my DAC but also have a technically better solution.
Cheers,
Tony
ps Update update:
I have now tried the I2S straight from the CPLD dev board straight into the TDA1541A using 3" of ribbon cable. (Not ideal) Sound is different once again, plus my timing issue with the WCLK is now fixed so it _was_ due to the reclocking. I feel the sound is now more mellow and relaxed, not so "in your face". I will be calling on Al's ears again (with his continued patience!) though I think to help me do an A/B test and help me come to a conclusion on which is "best".
#21
Right, ok i'd better say something then.
Firstly i think it's easier to pick up on changes in sound, when listening to your own system and familiar music.
Changing from I2s to SP-DUF left me unsure what, if anything, was really different, though i did think that bass was more prominent.
Going back to I2s however, something noticeable had happened. There was suddenly a clearer view of what was going on. Bass was a tad lighter perhaps but more defined. Decaying sounds went on longer, that sort of thing.
Don't want to sound like a reviewer cos i don't know what i'm talking about.
Anything that makes it easier to focus on instruments, has to be good.
Generally interesting stuff, and just beginning to make sense.
Firstly i think it's easier to pick up on changes in sound, when listening to your own system and familiar music.
Changing from I2s to SP-DUF left me unsure what, if anything, was really different, though i did think that bass was more prominent.
Going back to I2s however, something noticeable had happened. There was suddenly a clearer view of what was going on. Bass was a tad lighter perhaps but more defined. Decaying sounds went on longer, that sort of thing.
Don't want to sound like a reviewer cos i don't know what i'm talking about.
Anything that makes it easier to focus on instruments, has to be good.
Generally interesting stuff, and just beginning to make sense.
Much to learn there is.