Your modified DIC - (Digital Input Card) 
Hi Loris,
Yes its a standard BNC input DIC, however someone has added an RCA in parrellel with the BNC - however the RCA appears wired after the the AC coupling capacitor - which could cause problems depending on source. If you want to use the DIC with the RCA (not recomended due to the Risk of earth leakage current damage) - you should wire the RCA DIRECTLY in parrellel with the BNC - so before the Ceramic coupling capacitor.
John
Hi Loris,
Yes its a standard BNC input DIC, however someone has added an RCA in parrellel with the BNC - however the RCA appears wired after the the AC coupling capacitor - which could cause problems depending on source. If you want to use the DIC with the RCA (not recomended due to the Risk of earth leakage current damage) - you should wire the RCA DIRECTLY in parrellel with the BNC - so before the Ceramic coupling capacitor.
John
Balanced AES/EBU to 75Ohm SPDIF conversion.
"The Moog"
This is a LINK to an application note by Rane Corporation (RaneNote 149) which goes into some detail concerning Balanced AES/EBU to 75Ohm SPDIF conversion.
So long as the DEQ2496 has true balanced AES/EBU outputs (I.e. its outputs are transformer coupled), then as the input's of the MDAC are also Balanced you will still gain the benefits of Common mode rejection of a balanced link – with Fig 1. providing the impedance and signal amplitude conversion.
John
"The Moog"
This is a LINK to an application note by Rane Corporation (RaneNote 149) which goes into some detail concerning Balanced AES/EBU to 75Ohm SPDIF conversion.
So long as the DEQ2496 has true balanced AES/EBU outputs (I.e. its outputs are transformer coupled), then as the input's of the MDAC are also Balanced you will still gain the benefits of Common mode rejection of a balanced link – with Fig 1. providing the impedance and signal amplitude conversion.
John
Many thanks for that information John,
Seems that the DEQ2496's AES/EBU outputs are indeed truely balanced, so this looks like a good option for me. Any further news on when we might see it arrive here in the UK? Any pictures of it allowed out yet
?The Moog
Me too, as it seems the clock out on the new DAC is optical
Evening and Merry Christmas; for the last couple of days Ive been a happy owner of dacapo's first edition. While working with my cd player there were no problems. However, when i contected it to the satelite tuner with a coaxial output, i heard hardly audible distorted soud, similar to bee buzzing. Afterwards i turned the tuner off and turned it back on and the sound was all fine, no buzzing anymore. It was playing for about an hour and each time i was changing a chanel i heard a sound coming from the inside, a sort of a turning on clicking sound. While chaning the channels the red led was on. after a while the distorted sound i described in the begining came back and suddenly DAC stopped working, went completely dead. At the moment one led is red and one green and there is no sound coming from it. Capacitors look fine so i was wondering what could have caused the malfunction. id appreciate any help. thx
Hi, thank you for replying. My DAC doesnt work at all atm, as I said only one green led, the other one is red when I turn it on. Im not really good at electronics so would appreciate if you could explain a bit more what you mean by bypassing the output relay? I think it is some part that clicks when you turn the DAC on and sends the signal further that is broken and I dont know how to bypass it as what is going to steer the singal then? Thank you once again
Is it possible to send a picture?, mine only has red LEDS so I am not sure what you mean with respect to them. As far as I am aware the relay stops audio going out until the system has locked otherwise spits pops and bangs can come out of the unit, which it does on mine as they are bypassed. Bypassing in this case just means soldering a wire across the switching poles of the relay. So basically there is a good chance the converter works but the relay has gone, which is the most likely as electromechanical parts are usually the most unreliable parts of the system.
Hi Russel, thank you for replying. Attached are photos of my DAC. I have it in parts so would have to put it together to show you what I mean by the different colour leds. If DAC is on standby the LEDs are red, when it was working properly playing music, they were both green and now when I turn it on one is red and one is green and it doesnt play music.
Attachments
Relays
I can't comment on the 1993 version above, but on the later (1996) Dacapo the two relays near the metal cans are for de-emphasis. As far as I can tell they are only 'on' when de-emphasising. So should not be 'bypassed' or the treble will be attenuated.
The other relay toward the output is for muting the signal. I've forgotten now but according to my notes it does not switch the two signals, it just shorts them to earth at times. I presume I saw the tracks from under the PCB going direct from the Op-Amps to the output jacks and not cut at the relay. Hence it's just shorting. In that case this one should not be 'bypassed' either.
I can't comment on the 1993 version above, but on the later (1996) Dacapo the two relays near the metal cans are for de-emphasis. As far as I can tell they are only 'on' when de-emphasising. So should not be 'bypassed' or the treble will be attenuated.
The other relay toward the output is for muting the signal. I've forgotten now but according to my notes it does not switch the two signals, it just shorts them to earth at times. I presume I saw the tracks from under the PCB going direct from the Op-Amps to the output jacks and not cut at the relay. Hence it's just shorting. In that case this one should not be 'bypassed' either.
Ah, In that case they are not bypassed, it failed about ten or twelve years ago and it seems my memory is doing the same. I remember the problem lay with that relay but what I did now to fix it I cannot say for sure, maybe replaced it. There is a picture attached of my unit which is clearly a 93 model as the manufacturing date can be seen. There is also a replaced rectifier, which cannot be seen on the resolution of the picture, its in the middle on the right hand side. May be that drives the relay and the relay is normally closed.
Attachments
Hi, thats what i thought that my DAC is ORDINAL and not Dacapo. If it didnt break down, most likely I wouldnt find out about that I know which part is down- UA9637ACP- a part on the digital sound input card. I was therefore wondering if the problem with capacitors concerns only the Dacapo or ORIDINAL as well? ATM I have 24 capacitors which are SME and I presume these are Nippons- are these the ones that go down in Dacapo? If yes, I will exchange them as well. Moreover, if there are the same filters in dacapo and oridinal- is there a significant difference in sound and if yes would you know why? Is Dacapo also on 2x TDA1547? Cause if not, I think that the design of ORIDINAL seems to be a better one. One way or the other, Ive ordered different types of caps, from Elna to Rubicon, and will be testing various combinations on the power and digital-analog sections. My friend is already working on the introduction of valves (ECC88 or ECC83) on the analog section output and if this works out well, I think it might be one of the best analog sounding Dacs in the world. I have already compared it to the Arcam Diva 24bit/192 cd player and Arcam was more detailed and transparent. Is there anyone who would have 22 or 24 bit filter for sale? thanks
I know which part is down- UA9637ACP- a part on the digital sound input card. I was therefore wondering if the problem with capacitors concerns only the Dacapo or ORIDINAL as well? ATM I have 24 capacitors which are SME and I presume these are Nippons- are these the ones that go down in Dacapo? If yes, I will exchange them as well. Moreover, if there are the same filters in dacapo and oridinal- is there a significant difference in sound and if yes would you know why? Is Dacapo also on 2x TDA1547? Cause if not, I think that the design of ORIDINAL seems to be a better one. One way or the other, Ive ordered different types of caps, from Elna to Rubicon, and will be testing various combinations on the power and digital-analog sections. My friend is already working on the introduction of valves (ECC88 or ECC83) on the analog section output and if this works out well, I think it might be one of the best analog sounding Dacs in the world. I have already compared it to the Arcam Diva 24bit/192 cd player and Arcam was more detailed and transparent. Is there anyone who would have 22 or 24 bit filter for sale? thanks