Hooked up the DDDAC 1794 and it sounds Beautiful indeed! thanks DD for this design. Unfortunately I screw up one channel after dicking around with the wiring. One channel is quiet, I am not sure what the problem might be. I plan to complement with more boards anyway, but it would be good to know if the problem lies in the mainboard or the module board.
Regards Chris
Regards Chris
I really need to have a good look at these many pictures to make up my mind and get an opinion on your topic - sorry did not find time to do that (hopefully today or tomorrow
Hello All - Jumping on the Cinemag discussion and chipping in my observations: I use the CMLI 15/15B with 4 boards. I also find the overall bass impact lesser viz a viz the capacitor coupled output. I don't have any graphs or sweeps to corroborate what I am saying but reporting what I hear. I have been experimenting taking out the resistors on the secondary and I was not too sure if I heard a difference. I have I believe 15K Vishay Naked Z foils there. I also think others have also reported a perceived sense of impact with bass when they installed the Cinemags.
Just to clarify, I have checked and confirmed that the transformers wiring is connected properly as it should be per the colour coding.
My DAC sees the tube DHT 4P1L preamp which has I believe 50K input impedance. Is this 15K value of resistors across Cinemag's secondary for a 4 deck dack build ideal or am I going wrong anywhere? To think about it now, 15K source output impedance seems high for a 50K preamp.
Just to clarify, I have checked and confirmed that the transformers wiring is connected properly as it should be per the colour coding.
My DAC sees the tube DHT 4P1L preamp which has I believe 50K input impedance. Is this 15K value of resistors across Cinemag's secondary for a 4 deck dack build ideal or am I going wrong anywhere? To think about it now, 15K source output impedance seems high for a 50K preamp.
Thanks Doede, don't waste a lot of time on that, the measurements don't show a loss of bass, but subjectively it sounds like that when Cinemag doesn't have a 1K8-2K load. And when it has a 2K load, then it sounds subjectively worse than a capacitor. That's it, I have no explanation for this phenomenon. I also don't have an explanation for various other things in audio.
When I find the time to try Cinemag with 4 boards DAC I will write what the difference is.
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Hi Kartick, those are two different things, Load resistance of the transformer is one of course. The other where you talked about source resistance of 15k is where I reacted on. It is parallel to the source resistance. why 66? As both POS and NEG output ahs a 33 Ohm source and they are seen in series for the transformer. That is why.
Sure, thanks Doede. I knew I was misunderstanding something. Not very educated when it comes to electronics.
no worries Kartick, I know you are a true audiophile and love your music. All the rest, just ask - that is why we have this thread as well 
further to Eduard, no of course not - compared to your mechanical skills I would be the dummy - everyone has their own field of expertise. Mine happens to be electronics? (and cooking )
further to Eduard, no of course not
- compared to your mechanical skills I would be the dummy - everyone has their own field of expertise. Mine happens to be electronics? (and cooking )
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everyone has their own field of expertise. Mine happens to be electronics? (and cooking
If you cook like this, I am coming over!
Hello DD, Others,
I am late to the party but gonna order a Fifopi board, the two Accusilicon clocks to add to my DDDAC. My DDDAC consists of 4 older DAC boards mounted on a new Blue main board and am using WaveIO board for USB.
Before I place my order on Audiophonics, please could you look at the list of following things that I will need to add the Fifopi successfully to my build:
- 1 Fifopi board
- 1 ACCUSILICON AS318-B-451584 Ultra Low Jitter Clock 45MHz
- 1 ACCUSILICON AS318-B-491520 Ultra Low Jitter Clock 49MHz
- 1 4V PSU for J3
- 1 3.3V LT3045-78XX Ultra Low Noise LDO Voltage Regulator (J5)
- 1 47uf Capacitor (J5)
- 1 163ohm/5watt resistor (J5)
Am I missing out on any part? Please confirm so I can add to my order at once.
Also, I am very confused as to how the connections on the 40 pin connectors will be made? Which jumper/other cables should I order and from where? Is there anything available from Audiophoics itslef? Would I require the U-FL connectors?
You need two types of Dupont cables:
- Female (for WaveIO I2S and the very necessary ground wire) to Male (for the underside of FiFoPi)
AND
- Female (for the isolated J7 top side of FiFoPi) to Female (for DDDAC)
Audiophonics has them:
I2S 2.54mm Female / Female Cable 1 Pole Silver Plated 15cm (x5) - Audiophonics
I2S 2.54mm Male / Female Cable 1 Pole Silver Plated 15cm (x5)I2S 2.54mm Male / Female Cable 1 Pole Silver Plated 15cm (x5) - Audiophonics
The shorter the better for I2S. You do not need to get these from Audiophonics; they are widely available and can also be handmade without too much trouble if you are so inclined. You'll need metal header connectors, plastic housings, and a Dupont crimping tool. I use an IWISS IWS-3220M.
Dupont cables are the mainstream solution. Alternatively, you can also use U.FL-to-Female Dupont cables for the FiFoPi-to-DDDAC connection, but these are not commercially available, so you'll have to get U.FL cables, strip one end, and reterminate with Dupont header connectors. This is arguably the optimal signal path if you can do it.
Also, for the WaveIO-to-FiFoPi connection you can also use a 40-pin GPIO ribbon cable whose wires you separate to get just the ends you need. Doede has done this as well; he has done everything!. But it's spaghetti-like and not an ideal long-term solution.
The rest of your parts look good to me, but someone else should weigh in. Good luck!
Sure, thanks for your time. I will wait if a couple of more folks could give me a go ahead so I can order.