Have you checked that the BC550 and BC560 are in the correct place ? If not one of the transistors will get hot ...
Nice one, I had indeed swapped those. Man, I need some new readers. Seems to work fine now. Kudos for the swift, correct, advice!
DDDAC is up and running. I found a mis connected out lead (connected to common, not neg) and noticed noise with the CT from the transformer touching metal.
Getting a fair bit of distortion though. My power voltages are 5.1 to the Wave I/O board, and 11.2 to the DDDAC (blue board).
Getting a fair bit of distortion though. My power voltages are 5.1 to the Wave I/O board, and 11.2 to the DDDAC (blue board).
The swapped transistor is the most common fault so far. Seems to be tricky somehow.
On the distortion, Harmonic or digital? Did you check output voltages? Also, did you connect the transformers to the common and POS when live? Your transformers might have been magnetized... This could lead to distortion. But it could be other things, like wrong bias. Without transformers connected, do you measure 2.7 volt between pos- com and neg- com ?
On the distortion, Harmonic or digital? Did you check output voltages? Also, did you connect the transformers to the common and POS when live? Your transformers might have been magnetized... This could lead to distortion. But it could be other things, like wrong bias. Without transformers connected, do you measure 2.7 volt between pos- com and neg- com ?
Doede,
With regards to your ps, can two TIP122 be mounted in parallel?
Apologies if this is a dumb question?
Chanh.
With regards to your ps, can two TIP122 be mounted in parallel?
Apologies if this is a dumb question?
Chanh.
Can the TIP122 be replaced with TIP142 ? even though it is TO-3P. Maybe mount it on it`s own heatsink
You can do two parallel as long as they are thermally connected. Both need a resistor after emitter to make sure they balance
Tip 142 is also fine no problem use big heat sinks
Tip 142 is also fine no problem use big heat sinks
The sound was more of an unstability, another vibration mixed into the music. I will have to see of its only on one side or not.
Only one of the transformers was hooked up wrong, and it was for a short while. The first time I turned on the DDDAC the PSU worked for awhile. At that point I noticed one of the channels was lower than the other. No doubt due to the transformer mis-wiring.
I did get out of sorts with it yesterday, and put it up for awhile. I will get it out in a while and test those things: test the voltages, and test each channel separately.
Thanks Deode!
Doede, gentlemen, what do you think of adapting this for our boards ?
http://gilmore.chem.northwestern.edu/privstage.pdf
http://gilmore.chem.northwestern.edu/privstage.pdf
Last night I swapped the TIP122 for the TIP142. It will fit if you squeeze the leads with a pair of pliers to make them square.
Also fitted were 2 off Mundorf 10000uf 40v AG`s instead of the 4700uf and 2 off Vishay 470uf 40v to replace the Nichicon`s.
2A ceramic fuse now used instead of 1a.
I done a quick no load test and all is OK so far.
I will work on the heatsink later, it is BIG ...
Hum...
Hi everybody !
I have finished my DDDAC 😀, sounds great ! 😱
I have just a little problem of humming when the pot is going to high level, hum is coming.
I need to connect the cinemags to stereo pot for manage my two mono blocks but the issue is still there with any other amplifier. I see that if I connect ground to Cinch plug, it is OK but I think it is not a good solution:
Each components of the DAC are isolated from the metal case.
Any idea ?
Thank Doede for the great job, expect this litte issue, I am very happy ! 🙂
Hi everybody !
I have finished my DDDAC 😀, sounds great ! 😱
I have just a little problem of humming when the pot is going to high level, hum is coming.
I need to connect the cinemags to stereo pot for manage my two mono blocks but the issue is still there with any other amplifier. I see that if I connect ground to Cinch plug, it is OK but I think it is not a good solution:
An externally hosted image should be here but it was not working when we last tested it.
Each components of the DAC are isolated from the metal case.
Any idea ?
Thank Doede for the great job, expect this litte issue, I am very happy ! 🙂
We need visual proof of that! Only then can you proclaim to be the new king on the mountain. 😉
Next step, desolder the whole thing and put CCS's on all of them. 😉
Looks like you have a nice workshop.
Next step, desolder the whole thing and put CCS's on all of them. 😉
Looks like you have a nice workshop.
I too have this TIP142 working couple weeks already!
Stack of 16! Nice!! Look forward for the photos! 😉
Stack of 16! Nice!! Look forward for the photos! 😉
All working OK so far .... Now for the bedding in time 1 - 2 months.
The power supply heatsink runs at 35ºC which is fine by me as I leave the Dac on permanently.
Now I know 16 decks work OK, I want to make a double 16 stack one for left, one for right with dual power supplies using Lundhal chokes ... I like to think big 🙂
16 stacks is so July 2015
The power supply heatsink runs at 35ºC which is fine by me as I leave the Dac on permanently.
Now I know 16 decks work OK, I want to make a double 16 stack one for left, one for right with dual power supplies using Lundhal chokes ... I like to think big 🙂
16 stacks is so July 2015
Attachments
Very nice!
What sort of improvement(s) jumping from 11 to 16, were you noticed?
Unfortunately my enthusiasm for PCM DAC has damping down greatly after hearing a very good native DSD DAC. Will reroute the investments/energies to the DSD DAC here on! 🙂
What sort of improvement(s) jumping from 11 to 16, were you noticed?
Unfortunately my enthusiasm for PCM DAC has damping down greatly after hearing a very good native DSD DAC. Will reroute the investments/energies to the DSD DAC here on! 🙂
Hi Doede,
Just to inform you that I ordered the DDDAC kit with two power supplies and a 4-stacker- DAC broads. I expected VAT to be automatically deducted from the total price, once I selected Australian shipping address - but this did not happen... So, it seems that Audio Creative has done nothing, and it’s been a year since people initially complained about this issue.
I have contacted your distributor by e-mail and asked for a refund; however, may I make suggestion to you, to ask your distributor Audio Creative to AUTOMATICALLY deduct the VAT portion from the total cost, at the time when the order is placed? This will improve the overall buying experience.
Thank you,
Nick
The bass content and slam along with the transient reproduction. The soundstage gets deeper with better ambient clues and the treble and mid range get more lifelike.
I will have a longer listening session later but the improvements are not subtle 🙂