Twenty bucks for a complete DAC solution? How good could it sound?

[River757]

I saw this while poking around Amazon's site:

"Digital Optical Coax to Analog RCA Audio Converter Adapter" - $19.47, with wallwart power supply

Specs say it supports up to 96kHz/24bit PCM, but not sure if it is doing any downsampling.

Maybe it sounds halfway decent? Possibly a giant killer? Or maybe it really is only worth twenty bucks.

[SoNic_real_one]

"supports sample rates at 32, 44.1, 48 and 96 KHz"
This points to the early versions of Tenor (TE7021L) USB cip (doesn't do 88.4kHz and, based on that, I think 44.1 is internally resampled).

[Pano]

It doesn't cost much to put a receiver and dac chip on a PCB in mass quantities. Would be nice to know the chipset. C-Media, maybe?

[s3tup]

UDA1351TS? It is 96kHz with integrated DAC and SPDIF receivers. Single chip DAC

[jean-paul]

Hi, I made quite a few DACs with that UDA1351TS chip and it sounds afwul. I don't say this because I sell DACs but just to warn you. It produces sound and nothing more. To be honest: I recently threw away a batch of these DACs I made myself as I could not even want to sell them. Spend a few more $ if you want something that sounds OK.

[scott17]

I recently purchased the FiiO D3 for $30. It uses the Wolfson WM8805. I also bought an AD8656 opamp to replace TI LMV358. Haven't changed it yet. The device sounds great to me.

Here is a review: Inside FiiO D3 H i F i D U I N O

[jean-paul]

Hi I think you will have even better results if you put a true voltage regulator in the FiiO instead of the too simple zener diode. There exist nice TO92 3.3 V regs for that purpose. The Wolfson is very good and it deserves a good power supply so it can perform optimally.


I do not understand why they are so positive about the zener diode in the link....

[scott17]

Thanks Jean-Paul. That's a great idea. I think I'll do that when I change out the op-amp. Can you recommend a good TO-92 3.3V regulator for this application?

Thanks,

Scott

[SoNic_real_one]

Haha, zenner is "Shunt regulation"... It's the new fad.

[jean-paul]

Originally Posted by scitizen17

Thanks Jean-Paul. That's a great idea. I think I'll do that when I change out the op-amp. Can you recommend a good TO-92 3.3V regulator for this application?

Thanks,

Scott

Hi Scott, I think MIC5207-3.3YZ is among one of the better ones if you can still find it (out of production). LE33C is OK too.

LE33CZ - STMICROELECTRONICS - IC, V REG LDO +3.3V, TO-92-3 | Farnell Nederland

Anything better than a Zener diode I would almost say. Please do not use LP2950, it is way too noisy.