Mola Mola Tambaqui DAC and Streamer Review

[Matias]

@Todesengel you are right. I superimposed both on the same graph below. Bridged AHB2 (yellow) has the same max power as the NC1200 (purple) with a lot less distortion after 5W. Interesting!

Bring on the Purifi 1ET1200A!
(I just made that one up )

 

[Todesengel]

@Todesengel you are right. I superimposed both on the same graph below. Bridged AHB2 (yellow) has the same max power as the NC1200 (purple) with a lot less distortion after 5W. Interesting!

Bring on the Purifi 1ET1200A!
(I just made that one up )

View attachment 45364

I asked Benchmark if they had plans for a successor for a more powerful AHB2. They said there wasn't even anything on the drawing board for a new amp. I can't blame them, the AHB2 is selling like hotcakes (3 week lead time if you order today).

Maybe in my dreams a 1kW Benchmark amp

 

[bennetng]

gearslutz has a full database of results. Link points to a comparison between rme ufx+ and another interface.

The first two are still PCIE interfaces, it seems that they are hard to beat.

 

[orangejello]

In the ear review Bruno answers the question as to why he built his on DAC rather than using existing chips:

“I would have been happy to cobble it together from standard DAC chips etc, if there had been any way it would have checked off my complete shopping list:
1) No noise floor modulation.
2) Negligible distortion from tiny signal levels up to full output.
3) Jitter elimination down to very low frequencies.
4) Digital filters with negligible in-band ripple (i.e. no pre-echo).
5) Digital filters with moderately slow transition (i.e. reasonably short ring tails).
No DAC chip fulfils the first item in the list and no ASRC does the third (a discrete PLL without SRC conceivably could be built). The remaining three don’t seem to occur together in any standard chipset I could find. I was simply forced to take the long way round.
The entire story about how exactly it’s done is for geeks, but for me the secret is realising the importance of all five items mentioned above and getting them sorted by whatever means.”

Items 4 and 5 are interesting to me based on playing around with the RME filters. Any ideas why Bruno wanted to use a slow filter other than to get good impulse response measurements?

 

[Soniclife]

No noise floor modulation.

Does this show up in the tests done by @amirm?

 

[Giulio]

Does this show up in the tests done by @amirm?

Maybe from the fact IMD vs level is linearly decreasing.

 

[bennetng]

Any ideas why Bruno wanted to use a slow filter other than to get good impulse response measurements?

So that people can still use software upsampling to improve the appearance of graphs. Making everything too perfect would be boring, perhaps.

 

[orangejello]

So that people can still use software upsampling to improve the appearance of graphs. Making everything too perfect would be boring, perhaps.

Hmm. That doesn't sound like Bruno.

 

[617]

Damn str8. That's inconsistent presentation of the measurements.

We're expect Amir to enact a loudspeaker scoring metric and he can't even get the panthers right

 

[mansr]

4) Digital filters with negligible in-band ripple (i.e. no pre-echo).

This makes no sense. Firstly, pass-band ripple of decent chips is quoted at ±0.00001 dB or so. Not a problem by any stretch of imagination. Secondly, pre-echo doesn't exist in this context. It is can be an issue in lossy codecs (MP3) and occasionally in analogue media (tape print-through). Presumably, he means pre-ringing which is also a misnomer as the effect is not related to resonance.

It is disappointing to see a clearly competent person resort to bullshit in justifying his extravagances. Had he simply allowed the stellar performance to speak for itself, I'd only have been disappointed about the stupid slow roll-off filter. And the price.

 

[Deleted member 5620]

he can't even get the panthers right

Clearly the four or five panther-bits current in use isn't enough to properly quantize the score. We need at least 16 panther-bits...

 

[Hugo9000]

We're expect Amir to enact a loudspeaker scoring metric and he can't even get the panthers right

@amirm already addressed the Panther issue:

https://www.audiosciencereview.com/...-and-streamer-review.10770/page-3#post-300234

I use the soccer one for European products with the same value.

 

[MRC01]

This makes no sense. Firstly, pass-band ripple of decent chips is quoted at ±0.00001 dB or so. Not a problem by any stretch of imagination. ... Had he simply allowed the stellar performance to speak for itself, I'd only have been disappointed about the stupid slow roll-off filter. And the price.

A slow roll off filter isn't necessarily stupid; it can improve group delay. For example my DAC uses the WM8741 which has 5 choices for digital filter. At 96 k sampling, the standard brickwall filter (number 3) has a passband up to 40 kHz with stop at 48 kHz, group delay is 48 fs. The slow roll-off filter (number 5) has a passband only to 20 khz with stopband at 48 kHz, group delay is 8 fs. Both filters are linear phase, perfectly flat to 20 kHz and fully attenuated (-120 dB or more) at Nyquist. The slow roll off gives up a supersonic octave of frequency response we can't hear, to get flatter phase response and group delay in the passband.

Whether that is audible - is a different question. But it is at least a measurable benefit.

 

[mansr]

A slow roll off filter isn't necessarily stupid; it can improve group delay. For example my DAC uses the WM8741 which has 5 choices for digital filter. At 96 k sampling, the standard brickwall filter (number 3) has a passband up to 40 kHz with stop at 48 kHz, group delay is 48 fs. The slow roll-off filter (number 5) has a passband only to 20 khz with stopband at 48 kHz, group delay is 8 fs. Both filters are linear phase, perfectly flat to 20 kHz and fully attenuated (-120 dB or more) at Nyquist. The slow roll off gives up a supersonic octave of frequency response we can't hear, to get flatter phase response and group delay in the passband.

Whether that is audible - is a different question. But it is at least a measurable benefit.

Filter delay is of no consequence in a pure playback situation. After all, most of what we play was recorded years or decades ago. Another millisecond or two isn't going to matter.

Slow roll-off is at best harmless. If there is significant energy just below Nyquist, you get strong images just above, and the combination together with some IMD might result in audible degradation. At 96 kHz sample rate that's obviously not likely to be a problem, though.

 

[Matias]

Good reading Archimago's blind test on minimum phase versus linear phase upsampling:
http://archimago.blogspot.com/2015/07/the-linear-vs-minimum-phase-upsampling_10.html?m=1

 

[MRC01]

Filter delay is of no consequence in a pure playback situation. After all, most of what we play was recorded years or decades ago. Another millisecond or two isn't going to matter.

Slow roll-off is at best harmless. If there is significant energy just below Nyquist, you get strong images just above, and the combination together with some IMD might result in audible degradation. At 96 kHz sample rate that's obviously not likely to be a problem, though.

That group delay difference is not just latency. It is high frequencies more delayed than lower ones, aka phase shift.

 

[bennetng]

Good reading Archimago's blind test on minimum phase versus linear phase upsampling:
http://archimago.blogspot.com/2015/07/the-linear-vs-minimum-phase-upsampling_10.html?m=1

"Steep" filters on typical AKM/ESS chips are softer than SoX's default 95% already, let alone 99%. In fact my Realtek has a filter of similar steepness as the Mola Mola but no one cares about it LOL.

Archimago's measurement:
https://archimago.blogspot.com/2018/05/measurements-msi-x370-sli-plus-am4.html
Impulse Response (16/44):

Yup, a standard linear phase upsampling digital filter is used. Phase is maintained (non-inverting). It doesn't have much "ringing" on each side suggesting that the roll-off isn't particularly steep which we can see in the "Digital Filter Composite" graph...

Digital Filter Composite:



My measurement:
https://www.audiosciencereview.com/...gh-of-a-sample-rate-is-enough.4037/post-95240

Hmm. That doesn't sound like Bruno.

You can immediately see the benefit as people are talking about this behavior, otherwise there is almost nothing to talk about and the thread will sink quickly.

 

[audiophile]

Definitely. ASR's first intention is to "explode" high end snake oil.

I have no issue with very expensive gears if the performance is in SOTA territory!

Kudos to Mola Mola!

Topping D90 - SINAD 120.5 - $699
Mola Mola - SINAD 121 - $11,500

$10,801 for an extra 0.5 of SINAD? Definitely, not snake oil.

 

[VintageFlanker]

Topping D90 - SINAD 120.5 - $699
Mola Mola - SINAD 121 - $11,500

$10,801 for an extra 0.5 of SINAD? Definitely, not snake oil.

You missed the Mola Mola is also a Streamer and headamp. And yes, the Element X is a much better value with the same functionalities, but that's not my point. Well, what you pay when your get such expensive unit is also the design, the high end feel, the lifetime warranty, the fact this is a boutique DAC etc. Definitely a different universe and target.

We saw a ton of times gears which come with a fantastic story behind and at the end measure like shit. That is snake oil and it is clearly not the case here. By the way, we have the best measurements of all boutique DACs reviewed here. And that isn't nothing: this is exceptional engineering which deserves to be praised, even if the price/performance ratio is not competitive at all.

 

[Veri]

$10,801 for an extra 0.5 of SINAD? Definitely, not snake oil.

Spoken like a true @audiophile