miniDSP 2x4 HD Sweetspot-audio Mod Review

[JustJones]

Is DC different in EU? If we have a competent power supply does it matter if the AC is 50hz-240 or 60hz-120?

Could it be that the improvements are only achievable with the original power supply unit in the European power system?

 

[esl 63]

Comparing the two FFT graphs there is a difference. Third harmonic is reduced and higher harmonics is reduced. Only the 2nf harmonic is higher in the modded one. And for us who like science and win a wider perspective such as perception psychology and the science about what our brain detects as a disturbing distortion (higher order and odd harmonics) this is an improvement. For those only clever enough to look at a number (THD) that tells you nothing about what your brain detects as harmful OR rich. Ignore this message....

 

[pavuol]

…. Just went to their website. They even provide a so-called Tuning Certificate stating that the device has been improved. If I were a customer I would sent back my purchase and demand my money back according to their two year warranty.

From what I see apparently they are unable to test any of their work, so all the other mods they of at best work by chance. But likely do nothing or make things worse. I’d call that a scam.

Say what you say, I like the sticker!!

The review needs to update the title -"Platinum" Mod

[Sascha left the chat...]

 

[Sokel]

What a curious story. How do the mods cause these performance differences? Are we sure it's the mods that explain them? What did Sweetspot-audio measure as differences?

So many questions

What I suspect is their "improvements" has to do with it's analog performance I/O only,if any.
What is really odd is that this thing has been a subject of 38476583756 mods in diyaudio and none succeeded anything more than couple of dbs,except some really advanced ones who basically left just a memory of it on the PCB.

 

[SIY]

You forgot that the weather is different too.

And umlauts. Don't forget the umlauts. It's a significant difference.

 

[HarmonicTHD]

Comparing the two FFT graphs there is a difference. Third harmonic is reduced and higher harmonics is reduced. Only the 2nf harmonic is higher in the modded one. And for us who like science and win a wider perspective such as perception psychology and the science about what our brain detects as a disturbing distortion (higher order and odd harmonics) this is an improvement. For those only clever enough to look at a number (THD) that tells you nothing about what your brain detects as harmful OR rich. Ignore this message....

Oh we will as it lacks any foundation of actual proof.

As for the facts, 3kHz is better, rest is worse or almost unchanged and the company claimed THD improvement (not single harmonics) according to their website, so we only hold them accountable to their claim.

And btw what about the noise floor (ca 8dB worse)? You conveniently ignored this to spin your narrative (the company claimed that would improve too).

 

[JayGilb]

In their provided images the capacitor for DC power is upgraded to something a bit bigger. Not necessarily automatically meaning better performance even if it is now a Panasonic FM. (Or is it FC, I always mix up the two)

That's a big selling point in a lot of audio devices. If it has expensive caps, it must be better than other caps with the exact same specs.

 

[esl 63]

Oh we will as it lacks any foundation of actual proof.

As for the facts, 3kHz is better, rest is worse or almost unchanged and the company claimed THD improvement (not single harmonics) according to their website, so we only hold them accountable to their claim.

And btw what about the noise floor (ca 8dB worse)? You conveniently ignored this to spin your narrative (the company claimed that would improve too).

Random noise increase when we talk -125dB is maybe... well. Maybe you can hear it. My point is that IF you would hear any difference at all it would be for the better.
If you knew that your own ear is producing up to 10% 2nd harmonic, and that stated 0.001% of 2nd harmonic is not recognizable, and those amps with adjustable 2nd harmonic generation (yes there is such devices) can mask away odd harmonics and make the music experience more life like. and thats why we should not bother so much about the audibility of it compared to higher order and odd harmonics which is generated when amplifiers is clipping. Not hat pleasant if you are not into Heavy Metal where this effect is used not only on instruments but even on voice. One have to learn the audibility of odd and even harmonics and low order and higher order and the difference in how it is percieved by the brain. It is simply not science in an audio perception context to just sum the harmonic components in to one figure.

 

[wwenze]

Random noise increase when we talk -125dB is maybe... well. Maybe you can hear it. My point is that IF you would hear any difference at all it would be for the better.
If you knew that your own ear is producing up to 10% 2nd harmonic, and that stated 0.001% of 2nd harmonic is not recognizable, and those amps with adjustable 2nd harmonic generation (yes there is such devices) can mask away odd harmonics and make the music experience more life like. and thats why we should not bother so much about the audibility of it compared to higher order and odd harmonics which is generated when amplifiers is clipping. Not hat pleasant if you are not into Heavy Metal where this effect is used not only on instruments but even on voice. One have to learn the audibility of odd and even harmonics and low order and higher order and the difference in how it is percieved by the brain. It is simply not science in an audio perception context to just sum the harmonic components in to one figure.

The noise is not -125dB. The noise is -92dB. It only looks like -125dB on the graph due to "FFT gain" --> https://www.audiosciencereview.com/...nderstanding-fft-in-audio-measurements.20814/

Which is why the SINAD ends up worse because it is dominated by noise.

 

[pogo]

Is DC different in EU? If we have a competent power supply does it matter if the AC is 50hz-240 or 60hz-120?

The miniDSP was optimised in a different power grid system, including the typical interferers there. The result may look different on another continent. Noise does not only come from the power supply.
The power supply unit supplied was also not used!

 

[Deleted member 48726]

Well that's a waste of money! Thanks for making the review, Amir. Have heard about this upgrade and was curious to see how much they improved it.

 

[Deleted member 48726]

And umlauts. Don't forget the umlauts. It's a significant difference.

And all the signs towards Ausfahrt. Where ever that place is!?

 

[HarmonicTHD]

And all the signs towards Ausfahrt. Where ever that place is!?

Directly across from Einfahrt. ;-)

 

[HarmonicTHD]

Random noise increase when we talk -125dB is maybe... well. Maybe you can hear it. My point is that IF you would hear any difference at all it would be for the better.
If you knew that your own ear is producing up to 10% 2nd harmonic, and that stated 0.001% of 2nd harmonic is not recognizable, and those amps with adjustable 2nd harmonic generation (yes there is such devices) can mask away odd harmonics and make the music experience more life like. and thats why we should not bother so much about the audibility of it compared to higher order and odd harmonics which is generated when amplifiers is clipping. Not hat pleasant if you are not into Heavy Metal where this effect is used not only on instruments but even on voice. One have to learn the audibility of odd and even harmonics and low order and higher order and the difference in how it is percieved by the brain. It is simply not science in an audio perception context to just sum the harmonic components in to one figure.

The company summed it in one figure ie THD and claimed improvement (see their website), not @amirm . So your argument is a strawman.

(Yes, one can’t distinguish in all likelihood either device in an ABX listening test, but again, the company claimed improvements and failed miserably being it on the technical or on the audibility side of things).

 

[Ron Texas]

I found this review to be unusually informative as I use a Mini DSP 2x4HD in my main system. The measurements (unmodified) were better than I thought they would be. For anyone who does not think that is good enough the Flex is available. This device makes adding a subwoofer easy as it supplies both the crossover and delay. EQ is a bonus and it allows me to EQ the sound from my TV when watching Netflix.

Thank you @amirm

 

[JustJones]

The miniDSP was optimised in a different power grid system, including the typical interferers there. The result may look different on another continent. Noise does not only come from the power supply.
The power supply unit supplied was also not used!

This doesn't make sense to me it's like saying laptops need to be DC optimized or your email might screw up because power grids are different.

 

[Draki]

Directly across from Einfahrt. ;-)

On the Einbahnstrasse ....

 

[MAB]

People with oscilloscopes have measured worse noise results from their SMPS when they replaced the capacitors with even lower ESR ones. It is simply not easy to predict the outcome of the whole system by changing one part.

What does better mean anyway? LM4562 is better than NE5532 but has twice the current noise.

I do wonder if this Sweetspot modification has degraded performance due to inappropriate opamp replacement/rolling.

Rolling opamps seems really popular, even threads on ASR with people speculating on benefits from rolling opamps.

 

[Chagall]

The miniDSP was optimised in a different power grid system, including the typical interferers there. The result may look different on another continent. Noise does not only come from the power supply.
The power supply unit supplied was also not used!

miniDSP was optimized to work on 12V DC. The adapter accepts input of 100-240V, 50-60Hz. So continents won't make a difference.
Don't know what they meant by "improved 12V input voltage" though.

 

[Thomas savage]

At the bottom of the panther , is that a tail , something ' other' crawling Up its leg or something else far more impressive?