Grant Fidelity TubeDAC-11 capacitors

The caps i used are rated ±5% , don't know if at rated voltage.

I would definetly not use them in coupling applications, but for decoupling, i think they do a good job.

For Coupling i use Mundorf's silver and Oil in my Raphaelite DP84 amp and Yaqin SD-32A CD player, Soviet K40Y-9's in my Yaqin MS-300C amp , and Tube Amp doctor Vintage Oil Caps in my Sansui TU-70 Tuner.

I have not compared the difference while changing parts, but resulting sound is better than what im used to hear with this DAC.

Previously, i had a preference fot the sound of my Yaqin CD player, the TubeDAC-11 was too bright sounding, even with very good tubes, now, i have less distortion or 3rd harmonics than before.

I mostly listen to music from my PC, so the move was right.

Caps probably are in break-in while i listen.
 
Last edited:
Hopefully an easy question for you guys. The other TubeDac threads seem to be dead, so I ask here.

I am no longer using the tube output of the DAC. Can I use the DAC with the tube removed without fear of messing something up? (I don't want electrons running fast and loose into my world.)

Thanks!
 
I think that in absence of tube, the voltage of the current that normally go to the tube may rise, and some components like capacitors may not like this.
 
Last edited:
I just done another improvement to my TubeDAC-11

I added a 4.7uf multilayer ceramic cap to the 10uf solid polymer cap for the analog + supply of the DAC chip.

https://cjoint.com/c/HFBiDsr85gs

I also added a 120 ohms 1.8A NTC 120D15 thermistor between the main power switch and the voltage selector switch for a soft start and small voltage drop.

I first thought that the thermistor would produce heat, but the entire cover is cooler, the DAC runs cooler, works and sound very great.
 
Last edited:
Picture of my last work, you can see the seven 4.7uf 50V multilayer ceramic capacitors.

One on each of the five regulators.

One for the cap for analog power of the CS4398 DAC chip pin 22

And one for the cap for analog power of the CS8416 Digital Audio Interface Receiver chip pin 6 .

https://www.cjoint.com/c/HIgcdGg6LXs
 
Last edited:
What is the benefit to adding all these caps? I have a TD11 but I am unlikely to go through this process. However, curious minds want to know!
 
What is the benefit to adding all these caps? I have a TD11 but I am unlikely to go through this process. However, curious minds want to know!

Before I mod it, I was thinking the 6DJ8 was a bad tube with harsh and bright sounding characteristics.

I was tinking to buy another DAC (Eastern Electric Minimax DAC Supreme) with a 12AU7 to replace it, was thinking that since it is in another price range, it was in another league, but finally, after the TubeDAC mods, I realise that the only thing that the EE Minimax can bring to me, is the DSD capability, and I am not even sure it can be modded as easily as the TubeDAC or if it can even rivalise with it the way it sounds now, very satisfied with the results of my mods, It now sounds like a very high-end DAC , with the benifit of a tube.

Some more recent pictures

Added 4.7uf multilayer ceramic caps for some electrolytics, the only electrolytic caps that are not bypassed are the two caps in the rear of the unit close to the RCA outputs, as I am not sure if they act as output coupling caps, I will need to do more investigations about that prior to decide if I do something with them , like trying to replace them with film caps of same value if possible (Wima maybe). But the Wima of that value are big as hell. (47uf 63V if I remember corectly)
https://www.cjoint.com/c/HIgu7Gaxmas

Top side.
https://www.cjoint.com/c/HIgvahStwos
 
Last edited:
The Wima 47uf 63V are too big (W17 H29 L31.5 mm) to replace the electrolytic output coupling capacitors , I measured ≈23-24mm between the tube socket and the RCA outputs jacks sockets.

I don't know if I could gain anything by replacing the Elna Cerafine that are in place by anything else.
 
Back
Top Bottom