SMSL D1 - ROHM DAC for everyone

[sabih]

that is why i am asking a question. Its just a question

 

[Roland68]

has anybody tried to swap opamps on this DAC?

to get better objective performance numbers

Perhaps you should take a look at the performance figures for the D1 DAC first!?!

The AP measurements published by SMSL are always very consistent with Amir's measurements, so they are sufficiently reliable.
The op-amps are located in the I/V conversion/filtering stage of the DAC chip. If you are not able to adapt/calculate the circuitry for different op-amps, then you have a very high chance of making things worse.
In this case, it's not about the op-amp with the best measured values, but about the one that fits best into the circuit.

The Rohm DAC chips are not cheap, and Rohm certainly has a strong interest in delivering the best possible measurements. All evaluation boards use NE5532s, which are presumably also used in the D1.

In the D200, SMSL managed to slightly improve the measured values by about 2-3% with 8 op-amps, using the same DAC chip.
Do you think that will result in an audible improvement?
Guess what. I have both DACs on my desk...

 

[JSmith]

that is why i am asking a question. Its just a question

A question with an agenda no doubt... based on past posts and interactions with you.


JSmith

 

[Roland68]

Yeah I had to enable S4 and S5 sleep states first, so I could disable USB power during S5 state. D1 can now be left on as it will simply power up and down with the system.

That being said, my Fosi K7 came in, and I am left contemplating if I should maybe return the D1 now - don't get me wrong, there ain't nothing wrong with it, but the RCA outs of either trade blows with one another from what I can tell, and the K7 is a much more versatile device overall (and I didn't pay that much more for it in comparison).

I'll give it a few days as my return window is far from over, but I'm finding the K7 more useful right now.

The two devices aren't really comparable. The D1 is just a DAC, while the K7 is a DAC/HPA with an additional microphone input and a lot of functionality, including quick access to many features. It's ideal for gaming, which is one of the reasons Fosi designed it.
The K7 also received a very good review.
With the D1, you'd need at least an additional HPA.

 

[sabih]

A question with an agenda no doubt... based on past posts and interactions with you.


JSmith

agenda is to improve performance and that's it.

 

[KurtKlötentreter]

The two devices aren't really comparable. The D1 is just a DAC, while the K7 is a DAC/HPA with an additional microphone input and a lot of functionality, including quick access to many features. It's ideal for gaming, which is one of the reasons Fosi designed it.
The K7 also received a very good review.
With the D1, you'd need at least an additional HPA.

Certainly, and the K7 didn't just measure "fine" but quite well tbh. Even compared Amir's K7 measurements to SMSL's claimed numbers for the D1, the K7 looks great. Obviously this isn't to say the D1 is bad by any means, but I'm not sure I actually need the D1 now.

K7's digital volume control for RCA out allows me to bypass less than perfect pot low-gain (slight imbalance) so I can listen on very low volume without much trouble.

Definitely devices in separate classes, and I do like the simplicity of the D1, but would my ears ever notice that the delta sigma conversion is done by an AKM vs a ROHM chip? Unlikely

 

[conuss]

has anybody tried to swap opamps on this DAC?

What prevents you from trying and submitting optimistic results?

 

[sabih]

Ok will try to install opa1612 opamps in this DAC and will report

 

[Roland68]

Ok will try to install opa1612 opamps in this DAC and will report

If you have meaningful before/after measurements, or a second D1 DAC for a true blind test of original and modified D1s, that would be great.

Unfortunately, anything else is completely meaningless; I can assure you of that from 25 years of blind tests and 30 years of tuning experience.

 

[Scrivs]

DAC Fetish and low comprehension of the properties and function of electronics make humorous bed fellows.

 

[Evgenliman]

Hello.
Can anyone tell me what kind of chip this is?

 

[amanieux]

Perhaps you should take a look at the performance figures for the D1 DAC first!?!

The AP measurements published by SMSL are always very consistent with Amir's measurements, so they are sufficiently reliable.
The op-amps are located in the I/V conversion/filtering stage of the DAC chip. If you are not able to adapt/calculate the circuitry for different op-amps, then you have a very high chance of making things worse.
In this case, it's not about the op-amp with the best measured values, but about the one that fits best into the circuit.

The Rohm DAC chips are not cheap, and Rohm certainly has a strong interest in delivering the best possible measurements. All evaluation boards use NE5532s, which are presumably also used in the D1.

In the D200, SMSL managed to slightly improve the measured values by about 2-3% with 8 op-amps, using the same DAC chip.
Do you think that will result in an audible improvement?
Guess what. I have both DACs on my desk...

the rohm chip in d1 and d200 is $10(BD34352EKV) , unlike the rohm chip in d300 and dc-elite that is $100 (BD34301EKV), not sure how much of a difference it makes to the ear vs the second stage output amp that comes after the dac chip signal. so do you hear a significant improvement between d1 and d200 ?

 

[sabih]

Changed buffer opamp in d1 to opa1612 and I can confirm that it has made substantial difference in sound quality. I was not expecting this.
Wondering why SMSL didn't use opa1612/1656. Maybe because this is a low price category product.

 

[Svend P]

I was not expecting this.

We were.

Does Op-amp Rolling Work?

When I post my last video on review of Douk A5 amplifier, I mentioned that rolling (changing) op-amp ICs in there is fruitless. I got have a dozen comments under that video in youtube asking why so I thought I experiment again with the A5. Note that I have done the same testing with both DACs...

www.audiosciencereview.com

 

[KurtKlötentreter]

Changed buffer opamp in d1 to opa1612 and I can confirm that it has made substantial difference in sound quality. I was not expecting this.
Wondering why SMSL didn't use opa1612/1656. Maybe because this is a low price category product.

Measurements or its merely psychoacoustics ‍

But for real do you have any sort of data, measured anything about the mod? I found the idea of OP amp rolling quite fun, but virtually every test done with data to back it up found that rolling OP amps at best doesn't change sound in any meaningful way and at worst does actually degrade audio quality.

 

[kazuviking]

I can confirm that it has made substantial difference in sound quality.

Without showing any evidence its only in your head.

Can anyone tell me what kind of chip this is?

Gonna take you a clearer picture in a few hours.

 

[Roland68]

Changed buffer opamp in d1 to opa1612 and I can confirm that it has made substantial difference in sound quality. I was not expecting this.
Wondering why SMSL didn't use opa1612/1656. Maybe because this is a low price category product.

And you compared that to a second D1 in a real, externally controlled blind test and found out?

 

[Roland68]

the rohm chip in d1 and d200 is $10(BD34352EKV) , unlike the rohm chip in d300 and dc-elite that is $100 (BD34301EKV), not sure how much of a difference it makes to the ear vs the second stage output amp that comes after the dac chip signal. so do you hear a significant improvement between d1 and d200 ?

We haven't done the blind test yet, as it requires a certain amount of effort. Perhaps I can manage a simple comparison before Christmas.
However, I don't expect a significant or clearly audible difference, if there even is one.

Most insiders assume that the Rohm DAC chips are identical, come from the same production line, and differ only due to selection based on measured values.
The datasheets and evaluation boards support this assumption.
Given the small differences, these differences are more likely to occur in the mind and the evaluation of the measured values than in the sound and the music heard.

 

[kazuviking]

Can anyone tell me what kind of chip this is?

Its marked A08QQAIx

 

[kazuviking]

Most insiders assume that the Rohm DAC chips are identical, come from the same production line, and differ only due to selection based on measured values.

Because its the exact same chip but failed the binning to become BD34301EKV.