[Thorsten Loesch]

I found the idea of Super (capacitor) charging solution is very interesting. Just wondering if you know of any products that are using it?

There are a few more "esotheric" products, I think the Chord Hugo TT used supercapacitors and a few others do. It's rare though. I used them on the digital PSU of the iFi iDSD Pro.

Without load, the voltage of my capacitor bank can go up to 5.45V. Usually, what's the maximum voltage these capacitors can handle without getting into trouble?

I think the ones you use are rated 5.5V. You might want to see if the power supply can be dialled down a bit, I would suggest 5.25V unloaded.

I am also considering a similar solution for my pre amp that use DC 12V (it comes with a DC 12V 1A power supply). Looks like most of these super capacitors are rated with 5.5V. Do you think a super charging solution for my pre amp (12V) make sense? If yes, could you suggest a way for me to built one?

As it so happens I have just made a Supercap block for a 12V DC product.

I used 12F/5V Elna Dynacap DU, which internally really are two 25F/2.7V in series and were available on the local e-bay as surplus for very little money 3pcs for the equivalent of 3USD or a beer in a bar). The 12F/5V rated unit has around 50mOhm ESR.

I used 9pcs in total for 3pcs in parallel and then 3 sets of the 3pcs units that are now 36F/5.4V in series.

This gives a block of 12F/15V with 50mOhm ESR.

I tested the voltage sharing extensively and I got each capacitor at 2V +/- < 5mV through a bunch of discharging/charging cycles. This capacitor block delivered 1A nearly 30 Seconds while discharging from 12V to 8V.

So that is how easy it is to make a 12V Bank.

Thor

 

[Nkam]

There are a few more "esotheric" products, I think the Chord Hugo TT used supercapacitors and a few others do. It's rare though. I used them on the digital PSU of the iFi iDSD Pro.



I think the ones you use are rated 5.5V. You might want to see if the power supply can be dialled down a bit, I would suggest 5.25V unloaded.



As it so happens I have just made a Supercap block for a 12V DC product.

I used 12F/5V Elna Dynacap DU, which internally really are two 25F/2.7V in series and were available on the local e-bay as surplus for very little money 3pcs for the equivalent of 3USD or a beer in a bar). The 12F/5V rated unit has around 50mOhm ESR.



I used 9pcs in total for 3pcs in parallel and then 3 sets of the 3pcs units that are now 36F/5.4V in series.

This gives a block of 12F/15V with 50mOhm ESR.

I tested the voltage sharing extensively and I got each capacitor at 2V +/- < 5mV through a bunch of discharging/charging cycles. This capacitor block delivered 1A nearly 30 Seconds while discharging from 12V to 8V.

So that is how easy it is to make a 12V Bank.

Thor

Does a power supply bank like that help with the sound of the ZEN DAC Sig?
Does it make the DAC sound better and if so, why?

Thanks in advance!

 

[sunjam]

Final version of my super charging solution:

Now, it is USB-enabled (allow me to use it to power other 5V USB device.

Added a variable resistor to adjust the input voltage from the power supply (as the output voltage of my power supply is fixed, i.e. there is no variable resistor inside it for adjusting the output voltage):

 

[Nkam]

Final version of my super charging solution:



Now, it is USB-enabled (allow me to use it to power other 5V USB device.


Added a variable resistor to adjust the input voltage from the power supply (as the output voltage of my power supply is fixed, i.e. there is no variable resistor inside it for adjusting the output voltage):

Awesome work

 

[Thorsten Loesch]

Final version of my super charging solution:

Maybe. The wires look a bit weedy, thicker and twisted is recommended. Also, next time at Ikea or a store selling household goods look for a small wooden box to put things inside, for a less Heath Robins look?

Now, it is USB-enabled (allow me to use it to power other 5V USB device.

Again, twisted wires for +/-.

Also, if the original PSU can handle ~ 1.5A short out the D+/D- pins, that indicates "dedicated charger, 1.5A max.

Added a variable resistor to adjust the input voltage from the power supply (as the output voltage of my power supply is fixed, i.e. there is no variable resistor inside it for adjusting the output voltage):

Try replacing it with a 3A or larger (e.g. SB320) Schottky diode to drop a few 100mV.

Thor

 

[sunjam]

The following is part 2 of my work on Zen DAC V2...

Upgraded the capacitors to Panasonic OS-CON and ELNA SILMIC II. I think this should make it to become the Signature version.

Performance after the upgrade: it sounds much better than the original version. More details from bass to high. Overall, a good upgrade feel
Highly recommended as it only costs 4 Panasonic OS-CON and 2 ELNA capacitors. Yeah.

 

[Nkam]

The following is part 2 of my work on Zen DAC V2...









Upgraded the capacitors to Panasonic OS-CON and ELNA SILMIC II. I think this should it to become the Signature version.




Performance after the upgrade: it sounds much better than the original version. More details from bass to high. Overall, a good upgrade feel
Highly recommended as it only costs 4 Panasonic OS-CON and 2 ELNA capacitors. Yeah.

So you made it like the Sig right?

Nice

 

[sunjam]

So you made it like the Sig right?

Nice

I think so based on Thor's earlier comment as shown below:

After that, if you have the skills to work internally with surface mounted parts, upgrade the stock ZEN's to signature level. It's just replacing all SMD electrolytic Capacitors with either Panasonic Os-Con (power supplies) or Elna Silmic/Cerafine/Starget for the Audio section. These do make notable differences, but not as much as the power supplies.

 

[sunjam]

So you made it like the Sig right?

Nice

This is the official Zen DAC Signature picture:

The following is my "Signature":

Before the mod, I attempted to spot the difference between the official signature and the offical regular Zen DACs. The difference between the 6 capacitors are easy found. For the rest, it is hard to tell. V2 has the headphone amp but the Signature cut it.

 

[Thorsten Loesch]

Upgraded the capacitors to Panasonic OS-CON and ELNA SILMIC II. I think this should it to become the Signature version.

Yes, it does. You can go further and fit much larger value Os-Con's.

And you could fit a few Supercapacitors directly inside the case on the PCB at the DC socket. That would be "signature plus".

Performance after the upgrade: it sounds much better than the original version. More details from bass to high. Overall, a good upgrade feel Highly recommended as it only costs 4 Panasonic OS-CON and 2 ELNA capacitors. Yeah.

I agree.

Thor

 

[sunjam]

Yes, it does. You can go further and fit much larger value Os-Con's.

And you could fit a few Supercapacitors directly inside the case on the PCB at the DC socket. That would be "signature plus".

Cool, "Signature plus" sounds a good idea.

BTW, does all 4 OS-CON are for power supplies? One of the OS-CON is located close to the TI/BB chip while the other three are close to the power plug. From the official Signature picture shown above, looks like they use 330uF for the ones close to the power plug.

 

[farits]

You can go further and fit much larger value Os-Con's.

Can you recommend which ones?

 

[Thorsten Loesch]

BTW, does all 4 OS-CON are for power supplies?

Yes. And all are for 5V or lower supplies. You can easily go up to 820...1,000uF.

One of the OS-CON is located close to the TI/BB chip while the other three are close to the power plug. From the official Signature picture shown above, looks like they use 330uF for the ones close to the power plug.

No, they are for IC power. The three up front are for the USB Chip (XMOS) and clocks.

If you can find the capacitor connected to pin 14 (Vcom - I think it's C411 but check with multimeter on continuity), this should be a 1uF Film type (Panasonic ECPU is normally used on better products), but on the Zen's is a ceramic capacitor. A small size Wima MKP with 2.5mm pin spacing fil cap, this should fit.

Due to the way the PSU for the DSD1793 works, it is desirable to provide at least 5.25V DC from the external Supply. As much as 5.7V is safe for the Zen DAC, however it may trigger the overvoltage protection. In this case you have power on DC plug but the DAC does not work. In this case back off the voltage a trifle.

Because the Zen DAC run's directly from the PSU it receives (ok, with filtering and regulators) using a good quality linear power supply (e.g. the Aliexpress items I linked before) is very desirable.

With 5.7V you get a little more power and lower distortion from the Headphone Amplifier.

The quad Op-Amp U406 could be replaced by OPA1644, this needs a proper SMD rework setup.

The clock oscillators are decent, but better options exists. No need to replace 12MHz, just 22.5792/24.576MHz. Again, needs SMD rework setup, so usually a tech at a smartphone shop is needed.

If using the line output as fixed permanently, it is worthwhile to solder the switch pin's together, the switch will subtly degrade sound quality.

The volume control pot is decent, but not the best. With so many fake ALPS around it is hard to recommend replacements that actually fit. The pot has no impact on the fixed line out, so if using the Zen DAC as DAC only don't worry about the Pot.

Finally, "esotheric" measures, you can put self adhesive copper foil on the DSD1793 & Quad Op-Amp Chips and connect it to ground. Ideally the XMOS Chip too but that's a bit dicey to work on.

As PCB's can resonate and the common ceramic capacitors are microphonic, applying damping with self adhesive closed cell foam (some versions are backed with metal foil these are preferred) can damp resonances.

With a nice external 5.5V...5.7V linear power supply, upgraded capacitors as mentioned (and a few super capacitors) and perhaps some of the other mod's, you will have a DAC that will challenge the best iFi offers (I do not want to comment on other brands). Add a similarly upgraded Zen CAN and you will have something that is not really much worse than a Pro DSD & CAN, except power levels and features.

Thor

 

[Thorsten Loesch]

Can you recommend which ones?

Mouser part number 667-6SEP820M

Thor

 

[sunjam]

Yes. And all are for 5V or lower supplies. You can easily go up to 820...1,000uF.



No, they are for IC power. The three up front are for the USB Chip (XMOS) and clocks.

If you can find the capacitor connected to pin 14 (Vcom - I think it's C411 but check with multimeter on continuity), this should be a 1uF Film type (Panasonic ECPU is normally used on better products), but on the Zen's is a ceramic capacitor. A small size Wima MKP with 2.5mm pin spacing fil cap, this should fit.

Due to the way the PSU for the DSD1793 works, it is desirable to provide at least 5.25V DC from the external Supply. As much as 5.7V is safe for the Zen DAC, however it may trigger the overvoltage protection. In this case you have power on DC plug but the DAC does not work. In this case back off the voltage a trifle.

Because the Zen DAC run's directly from the PSU it receives (ok, with filtering and regulators) using a good quality linear power supply (e.g. the Aliexpress items I linked before) is very desirable.

With 5.7V you get a little more power and lower distortion from the Headphone Amplifier.

The quad Op-Amp U406 could be replaced by OPA1644, this needs a proper SMD rework setup.

The clock oscillators are decent, but better options exists. No need to replace 12MHz, just 22.5792/24.576MHz. Again, needs SMD rework setup, so usually a tech at a smartphone shop is needed.

If using the line output as fixed permanently, it is worthwhile to solder the switch pin's together, the switch will subtly degrade sound quality.

The volume control pot is decent, but not the best. With so many fake ALPS around it is hard to recommend replacements that actually fit. The pot has no impact on the fixed line out, so if using the Zen DAC as DAC only don't worry about the Pot.

Finally, "esotheric" measures, you can put self adhesive copper foil on the DSD1793 & Quad Op-Amp Chips and connect it to ground. Ideally the XMOS Chip too but that's a bit dicey to work on.

As PCB's can resonate and the common ceramic capacitors are microphonic, applying damping with self adhesive closed cell foam (some versions are backed with metal foil these are preferred) can damp resonances.

With a nice external 5.5V...5.7V linear power supply, upgraded capacitors as mentioned (and a few super capacitors) and perhaps some of the other mod's, you will have a DAC that will challenge the best iFi offers (I do not want to comment on other brands). Add a similarly upgraded Zen CAN and you will have something that is not really much worse than a Pro DSD & CAN, except power levels and features.

Thor

Wow... it is wonderful. Thanks a lot for your comments. Looks like there are more homeworks for me to do.

"With 5.7V you get a little more power and lower distortion from the Headphone Amplifier" <=== As my super charging solution is based on 5.5V capacitor, would it be ok to use it with 5.7v input?

BTW, for the 5.7V you mentioned, does it refer to the voltage under load (i.e. connected to the Zen DAC) or w/o load? I have a multi-meter connecting to my capacitor bank in order to monitor the real time output voltage when it is connecting to the Zen DAC.

With my 5V LPS, I can only push it up to around 5.27V (stabilized).