A NOS 192/24 DAC with the PCM1794 (and WaveIO USB input)

To be honest, no i haven't tried the 0.5W but it was recommended to me by someone who knows his stuff but doesn't sell them.
With a non commercial biased answer i thought i did the right thing then.
Ouch, i see you talk about the silver version.....i have bought the non magnetic Tantalum version
 
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Hello Norway,
When i was looking for a resistor to use at that spot i could only found the Shinkoh 2 watt. If i remember well the Audio note resistors available at that time were not the right the value for a 4 deck dddac. The new series have a 2 watt in that value?
I remember buying a few of these two watt resistors for a phonostage that was build by me. It was a pretty hefty invoice for la handful of resistors.
I remember buying the original Shinko 0,5 watt resistors in Paris 3 decades ago for less than 2$. These were considered expensive at the time.
So after finishing my new tiny power amp, going Fifopi, new clocks, lifepo4, supercaps i might try these 2 watts too.
Greetings, Eduard
P.s the attachment is a new copper chassis, 440*440*68 mm ( this is the power supply part including the ultra path caps. The signal part is 440*193*68 and will the attached to the bigger part by means of a wooden frame.
 

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Hello Norway,
When i was looking for a resistor to use at that spot i could only found the Shinkoh 2 watt. If i remember well the Audio note resistors available at that time were not the right the value for a 4 deck dddac. The new series have a 2 watt in that value?
I remember buying a few of these two watt resistors for a phonostage that was build by me. It was a pretty hefty invoice for la handful of resistors.
I remember buying the original Shinko 0,5 watt resistors in Paris 3 decades ago for less than 2$. These were considered expensive at the time.
So after finishing my new tiny power amp, going Fifopi, new clocks, lifepo4, supercaps i might try these 2 watts too.
Greetings, Eduard
P.s the attachment is a new copper chassis, 440*440*68 mm ( this is the power supply part including the ultra path caps. The signal part is 440*193*68 and will the attached to the bigger part by means of a wooden frame.

Chassis looks awesome. Did they laser cut or punch it?

Edit, I can see they punched it.



TCD
 
Rhopoint GG102

When talking about I/V resistors. Have anyone of you tried these: General Resistance GG102 Squaristor Series | Rhopoint Components

A couple of years ago I bought a bunch of custom value 0.1% 133ohm Rhopoint GG102 resistors for myself and some of my single board DAC friends. Very transparent and neutral sounding without any edginess. They cost about $10 each including shipping, but it took two months to get them. Four needed for DAC board. Wattage rating too low for multiple DAC board loads.

As shown in the picture, I eventually made my own custom DAC boards with a buffer on the main board and ADM7150 Vreg circuits for the digital components and digital side of the PCM1794 chips. I use external Salas 1.3 version power sources for all analog devices. Very analog sounding.
 

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Chassis looks awesome. Did they laser cut or punch it?

Edit, I can see they punched i

Hello Terry,
Sure i punched on a CNC machine at work. Using 13 different punch tools. Only the big round holes that would be visible like the 39 mm circle for the rectifier are made with one tool 39 mm in one stroke because it looks nicer. The big rectangular holes are made with square tools like 8/15/20/30/40 mm in several strokes. Only 8 mm is one that is not standard in every day use so takes a few minutes to prepare it. Holes like round 3/3,2/4/5/7/10 are always ready to be used. So usually the preparation of the machine would take 5 minutes to 30 min. maximum.
What is really time consuming is getting all the dimensions right.
The stainless steel part that is glued onto the terminal side takes a few minutes to '' design '' . I will write down ( no PC) the dimensions needed for mounting, the 5 M6 studs and the two holes for the terminal to pass. THEN have to program it on the exact position on the chassis. Same like the tube rectifier and the aluminium 57 mm circle. I dont have a cad/cam program on my pc at home so have to visualize it in my mind mainly. Sometimes when the holes are a bid odd like the panelmeter i will just do a test to find out the right combination of dimensions.
About 40% of the copper sheet ends up as scrap. It is to expensive to make a second attempt.
I must confess i like the looks too. All the metal elements on top will be stainless steel except the big Russian capacitors. They have an ugly colour so i will remove the paint and leave them with an ordinary steel look. Once polished and not being touched they will keep that look.
Same like the polished copper. Can be maintained by the same product they use for brass instruments
Greetings, eduard
 

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Have you solved the strange issue with your dac @leifchristensen?

well, the real problem behind is not "solved" - but the at least we could exclude the DAC from being the issue. I received it yesterday, put it on the Bench and everything tested 100%.

So for Leif the search goes on :confused:
 

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hello DD
experienced something really weird today
my dac seem to have lost the bass foundation in the sound and e.g in we get requests with oscar peterson and ray brown, ray is really far away in the distance and the sound is slightly tinny and lightweight
thought it might be the new Fifopi reclocker board, but sound is approximately same with dac spdif input fed directly from Studer a727 used as drive
you might remember I run the dac straight into a TVC and thus I don´t have any output caps or extra transformers on the output
any idea what might result in sound as if sent through a hipass filter? must be up in min 3-400hz range
any ideas are welcome
best
Leif
Hello Leif,

I am new on this forum although using DDDAC since some years now.
I experimented similar issue as yours. DAC sounding "tiny". It came progressively after a full rearangement of boards and output transformers. I believed it was related to my speakers as they are active on lows. Wanting to do some more experiments, I decided to switch DAC "Old models" -> Tents regulated new version. Removing the DAC I noticed the 12V input cables were not firmly tighten. I put evrything back in place with properly tighten connector and then the old DAC was making proper basses not being tiny anymore.
Not sure you had same issue but may give you a hint where to search.
Best
Tristan
 
I have 3x old red V2 main boards, 3x black V3 dac boards and 2x black V2 dac boards

I plan to have one main board with 2x V2 dac boards "as is" and experiment with the others

This thread is so huge I am not sure where to start, but can anybody suggest the mods recommended for the old red main board and V3 dac boards?

I also plan to only use 75 ohm I2S from my CD transport or squeezebox, not USB for the time being. It looks like the red main board does not have a 75R resistor onboard, can someone please confirm is this is the case?

Finally, I was thinking of using a Lundahl LL1572 input transformer, anybody tried this with the DDDAC?

Many thanks
 
Hello Leif,

I am new on this forum although using DDDAC since some years now.
I experimented similar issue as yours. DAC sounding "tiny". It came progressively after a full rearangement of boards and output transformers. I believed it was related to my speakers as they are active on lows. Wanting to do some more experiments, I decided to switch DAC "Old models" -> Tents regulated new version. Removing the DAC I noticed the 12V input cables were not firmly tighten. I put evrything back in place with properly tighten connector and then the old DAC was making proper basses not being tiny anymore.
Not sure you had same issue but may give you a hint where to search.
Best
Tristan
absolutely worth trying once I get it back
best
Leif