SMSL D300 Review (Balanced DAC)

[pickyAudiophile]

Are you sure the older firmware can be installed to newer devices with firmware 1.21?

For me it worked properly, then time, I mean downgrading back to initial firmware version, down from that later release provided inside this thread. But 4 + years have gone by since... D300 buyer on eBay gave me positive review and within a month did not open a case.
@vazakh I used to put in-line-attenuators in between DAC and amp for protection, -12dB did the job just fine to tame potential excess volume risks. I am on the cautious side, too. Bad things can happen easily. Like just e/g broken-off-from-PCB RCA jack ground connector latches which suffered too much of tear and wear by flexing from user's in-and-out plugging.

 

[bogi]

For me it worked properly

It could, but there are many reports published in this thread about devices bricked during downgrade. It looks to me that at least some batch of devices, or from some time point all newer D300 devices were produced with a slightly different hardware. That could cause incompatibility issues with older firmware not intended for these devices.

Read from here about 10 posts: https://www.audiosciencereview.com/...l-d300-review-balanced-dac.28919/post-1791132

 

[vazakh]

Это не связано напрямую с D300, но, скорее всего, вызвано проблемами заземления нескольких устройств, включая усилитель.

If this problem is related to grounding, what are the ways to solve it?

 

[Roland68]

If this problem is related to grounding, what are the ways to solve it?

As mentioned, grounding problems can be very complex and always involve multiple devices.
With USB connections, the simplest solution is galvanic isolation. The most reliable method is via an optical connection, for example, from a PC/Mac, if available, or via a DDC, such as the PO100 2024 or PO100 Pro.
Alternatively, galvanic isolation via USB is possible, for example, with an Intona USB isolator. Be careful with inexpensive USB isolators; they may work well, or they may not.
Anything else requires measurements or a lot of trial and error.

Often, the problem is related to the PC/Mac and the amplifier. Some of our measurements have shown that the crackling noise/pulse was already present in the USB signal and disappeared when a different amplifier was connected.

 

[Roland68]

I guess the DO300EX doesn't suffer the afflictions of it's ES9039... sibling. Have nothing but high praise for the EX. The quality is first rate too.

This thread is about the D300 ROHM DAC, which has nothing to do with the DO300 or the other ES9039 DACs.
The D300 hasn't actually had any problems since the update. Grounding issues and problems with the optical connection, especially with TVs, can occur with all DACs.

 

[redjr]

Ah ha, I see. My old mind gets confused from time to time. Thanks for informing/correcting me. But, I did have that DAC a few yrs ago. Had forgotten it used the ROHM DAC chip. Was not too impressed mostly with the build quality so I returned it. Since then SMSL have really stepped up their quality, and DAC electronics game. I currently, have 3 of their DACs; SU-1, D-6s, and the DO300EX. I know the 300EX is a little older model, but it had the connectivity I wanted, plus a respectable headphone amp - capable of driving my Hifiman Edition XS cans with ease. Music sound marvelous.

 

[vazakh]

I solved the clicking problem, albeit with some workarounds. I'm transmitting the signal through a USB-to-optical converter. No clicking at all.

 

[Roland68]

I solved the clicking problem, albeit with some workarounds. I'm transmitting the signal through a USB-to-optical converter. No clicking at all.

This actually points to a grounding problem and not to something that only arises in the DAC.
Glad it's working for you now.