Thank you JP and Subbu for this great project. My first SMD project (and my first after 10 years). Sounded great - smooth and refined. However, it had intermittent stutter - it was as though it could not lock onto the signal. After 3 weeks, I decided to leave it on for 4 days - eventually it stopped working. I suspect I could have fried the XO. Used 15uF for C8 and 13, 1.5uF polyester for C35, 1uF PPS for C31.
Attachments
My first DAC sounded great but I wished it had a little more 'air'. It also died. So I used my favourite Goot 2.5% silver/tin/lead solder instead of Kester 63/37 for my second attempt. The Goot solder seems to flow better. Decided to try the EPSON SAW oscillator XG1000CA as it is 0.2mm smaller - psychologically it seems easier to solder. (Available from Farnell). Does it sound better? I can't compare but it doesn't sound bad.
Tried the SEPC 100uF (only one I had) on C22 initially. Very airy/fast but seems to lack body/bass. So I decided to use a 470uF Oscon I had lying around. Not so airy but much better balance. JP will have a fit seeing a 5mm pitch capacitor on C22. I have one last board. May try a 330uF 16V standard BG I have lying around but I must say the if the 470uF SEPC has the bass of the oscon and the airiness of the 100uF SEPC, it will be great.
Anyway, many thanks for those who have contributed so much to this project. Certainly, it has been fun building it. How I wish the boards are still available. I am sure it will continue to be a great project for 1st time builders.
Regards
Tried the SEPC 100uF (only one I had) on C22 initially. Very airy/fast but seems to lack body/bass. So I decided to use a 470uF Oscon I had lying around. Not so airy but much better balance. JP will have a fit seeing a 5mm pitch capacitor on C22. I have one last board. May try a 330uF 16V standard BG I have lying around but I must say the if the 470uF SEPC has the bass of the oscon and the airiness of the 100uF SEPC, it will be great.
Anyway, many thanks for those who have contributed so much to this project. Certainly, it has been fun building it. How I wish the boards are still available. I am sure it will continue to be a great project for 1st time builders.
Regards
Attachments
...finally finished this DAC:
- enclosure 132x160x66mm from Custom Electronic Enclosure UnioBox 66 - Lincoln Binns
- front and back panels from Front Panel Express
- self taping torx screws from AccuGroup - Precision Engineering Components
- vandal switch from Schurter
- insulated 75ohm BNC from TE Connectivity
- IEC Filter from Schaffner
Thanks a lots to JP, Subbu and Philippe (Korben).
Hi, for the intermitent stutter : did you try to go back the PSU from the source and/or the pcb. i had the same problem with my SqueezeBOx : the IE transformer generate many EMI/EMC.... 20 cm mini is the solution at home with my squeeze box. You can try to reflow carrefully all the leads of the two chips with a magnifier glass !
Your Oscon is a good choice because your C18 seems to be a sepc. My experience is both C18 & C22 with SEPC is too much thin sound and bad tonal balance.
I would change your C35 : I tried this cap : bader than a more neutral MKS2, go for Black gate here if you have, even a standard BG is better than this one which not give a natural balance (artificial treble). Download the pdf I made in the modyfing Subbu thread, it will help you to understand the relation of the caps between their respectiv positions.
Your Oscon is a good choice because your C18 seems to be a sepc. My experience is both C18 & C22 with SEPC is too much thin sound and bad tonal balance.
I would change your C35 : I tried this cap : bader than a more neutral MKS2, go for Black gate here if you have, even a standard BG is better than this one which not give a natural balance (artificial treble). Download the pdf I made in the modyfing Subbu thread, it will help you to understand the relation of the caps between their respectiv positions.
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Did you sucees to avoid intermitentt stuter by go back the suplly from both the source and the main PCB ?
If you have one DAC working, try on your second if C18 is a SEPC : C22 with Nichicon Le 470/6.3V; Gary e.g. prefer an other cap... depends greatly of your speakers and the global transparency of your system. I think your ocscon is good enough and certainly better here than a 470 SEPC imho. i never liked the 100 uf SEPC at C22 with all the different C18 I tried, but 470 uf sounds good here, but with my system it's not my first choice... each system have different tonal balance and needs... At C35 the Wima will give in most system I surmise : both body and mid-bass as lighty trebles but not brighty, medium was a little digged in my system. Stay a very good choice over all the MKT I tested (see my photographs) : many use Cornel dublier MKT than I have to try in thr future like the 2 mm pitch 1 uf Wima MKS2 for C32... but sorry here cuse it's not the moddyfing thread. Wanted mainly to know if your problem was resolved with th eintermitent stutter ?
What is your source ? a CD player ? Last thing : what oscon do you have exactly ? Sanyo SP, Sanyo without grade, Sprague ?
If you have one DAC working, try on your second if C18 is a SEPC : C22 with Nichicon Le 470/6.3V; Gary e.g. prefer an other cap... depends greatly of your speakers and the global transparency of your system. I think your ocscon is good enough and certainly better here than a 470 SEPC imho. i never liked the 100 uf SEPC at C22 with all the different C18 I tried, but 470 uf sounds good here, but with my system it's not my first choice... each system have different tonal balance and needs... At C35 the Wima will give in most system I surmise : both body and mid-bass as lighty trebles but not brighty, medium was a little digged in my system. Stay a very good choice over all the MKT I tested (see my photographs) : many use Cornel dublier MKT than I have to try in thr future like the 2 mm pitch 1 uf Wima MKS2 for C32... but sorry here cuse it's not the moddyfing thread. Wanted mainly to know if your problem was resolved with th eintermitent stutter ?
What is your source ? a CD player ? Last thing : what oscon do you have exactly ? Sanyo SP, Sanyo without grade, Sprague ?
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TO DESOLDER IT : be very carefull for the golden pads ! desolder first the ferrite bead between the crystal and the dac (to isolate the last from heat) and between the crystal and the output cap of the ldo (to isolate the ldo from heat)
try first desoldering braid; after heat each pad and try to do level arm with a screwdriver between the golden pad and the crustal, beginning with the output pad, second : voltage pad, third: gnd ; the last is not connected, so not important if you break it !
gently, softly.... take your time
good luck, just 2 cents as i did it myself on one of my Subbus !
try first desoldering braid; after heat each pad and try to do level arm with a screwdriver between the golden pad and the crustal, beginning with the output pad, second : voltage pad, third: gnd ; the last is not connected, so not important if you break it !
gently, softly.... take your time
good luck, just 2 cents as i did it myself on one of my Subbus !
Hello,
I've done all the soldering of my subbu dac, which is also my first smd project, but I get no sound.
I've measured all the voltage and get some bad numbers :
- C23 : 1.59V
- C11 : 1.92V
- Q2 : 0V everywhere... and 0V after Q2
Do you think I've fried Q2 , might there be other problems ?
Apart from these other measures seem OK.
Thank you
I've done all the soldering of my subbu dac, which is also my first smd project, but I get no sound.
I've measured all the voltage and get some bad numbers :
- C23 : 1.59V
- C11 : 1.92V
- Q2 : 0V everywhere... and 0V after Q2
Do you think I've fried Q2 , might there be other problems ?
Apart from these other measures seem OK.
Thank you
Hi
Try to check your solder pins first.
Q2 might not be fried, but your voltages are wrong.
A pic could help
Regards
Phil
Thanks for your help !
Here is a picture :
An externally hosted image should be here but it was not working when we last tested it.
Do you want me to send a zoom on Q2 ?