ProtoDAC TDA1387 X8 project

[speedy210]

Hello, is this the assignment for the Gipos to connect the ProtoDac outside the Raspberry interface?

[hifinet]

Yes. 12, 35, 40 and share ground at 6 or 14 or the GND pad between the RCA jacks. 5V at 2, 4 or the 5V pad between the RCA jacks can be shared or separate.

[nas963]

Hello,
while waiting for my printed circuit boards to arrive, I started sourcing components.
Since the selection of quality components in my country (Serbia) is poor, and buying online is not an issue, but shipping and customs double the price, I have a question.

I found Obbligato Gold MKP polypropylene capacitors available for purchase, and I’m wondering if anyone has experience with them and whether they are worth getting instead of, for example, WIMA MKP4.

While reading forums, I came across issues with Obbligato capacitors, so I’m curious whether the problem is with specific units or the manufacturer itself.

[hifinet]

What issues are you referring to regarding Obbligato caps?

[nas963]

What issues are you referring to regarding Obbligato caps?

In post #619 you talk about loud pop at the beginning of the very first track played

[hifinet]

You can eliminate or reduce it by bypassing the cap (adding another cap in parallel) with a small value cap (for example, 0.1uF).

[hifinet]

More I/V resistor listening. I think the Vishay 100R X4 are eliminated. The Vishay Dale CMF 412R (CMF55412R00FHEB) sounds very good, but lacks bass and treble. At only about $1 USD for a pair, I think it would be a good choice if you are trying ProtoDAC for the first time, and want to limit cost.

Again, as @thomaschan discovered, bass and detail is better with lower value I/V resistors. 100R will require about 15dB of additional gain. As previously stated, if you have that amount of extra gain with your preamp, I would recommend lower value I/V resistors.

[speedy210]

Hello, I have a problem with protodac with one channel. One channel is quieter than the other. It is not due to the speakers or the cable. Does anyone know where the problem could be?

[hifinet]

Either the I/V resistors are unequal in resistance or the TDA1387 X8 module is bad.

[speedy210]

Either the I/V resistors are unequal in resistance or the TDA1387 X8 module is bad.

ok thanks. Then I will desolder the things and check them.