miniDSP 2x4 HD Sweetspot-audio Mod Review

[Toni Mas]

And this is with high level signals. Now try this 60 or 80dB lower.

And so what? The question is how deep below the noise level a pure tone Will become masked by noise. Rms makes no sense here because different signals have different rms to peak ratio, so that peak valué is the only posible reference.

 

[RandomEar]

Thanks for the inputs, i am curious to try.
But i am not discussing noise audibility, but the audibility of a signal under the noise level. I mean same as these -80 dB of noise might be audible in your tweeters why should this noise mask an H3 or H5 at -83dB making these HD products inaudible?

OK. I agree that for music at a reasonable and audible level X, adding some (rather extreme) noise of the same level X to it won't make the music inaudible. But if you now also add distortion at the same level X to the signal, I think the noise will be far, far more apparent and - even with noise and distortion at the same level - will be the major "perpetrator". And the reason is simple: Energy. Distortion is only present at a handful of specific frequencies. Typical pink noise is present at all frequencies and therefor carries sifgnificantly more energy in the signal, giving it a higher power to mask other parts of the signal. Including distortion.

I would say that's also in agrement with my argument that it's really, really hard (for me) to identify distortion at around -36 dB in real music, but noise at that level is quite apparent. Try it: Generate pink noise in Audacity, normalize it to -36 dB and play it alongside music at a comfortable level. It's audible and in an A/B test you would identify it immediately. Takes maybe a second or two to hear it. Distortion at that level will hardly be audible at all, even in a well controlled A/B test. If that is true, then why wouldn't noise at a level X fully mask any distortion at that level and lower levels?

 

[Toni Mas]

I would say that's also in agrement with my argument that it's really, really hard (for me) to identify distortion at around -36 dB in real music, but noise at that level is quite apparent.

Soundwise -36dB Total HD means nothing at all, just a figure for engineers... What harmonic content are you talking about? Pure H2? So ok, barely audible... But what is the exact harmonic content of these 36? And please keep noise apart (sinad), because noise is a different animal, a random one and thus uncorrelated to the signal, and btw there are noises of many colours too...

 

[OldTimer]

Since it is a mod by a german manufacturer, I would say this it the wurst product.

What happened to the germans? They have Rheinmetall manfacturers along with Taurus missiles

 

[Paffi]

I contacted Sweetspot yesterday and already got a reply. I have to agree with Ah-ra that it would have been better to get a statement from him bevor publishing the review. It can indeed have a negativ impact on his business and therefore deserves a fair chance. He also wrote that he values all the hart and work Amir put's in to this site even dough he is no member.

@amirm He would like to know/verify the following things:

Did you get any response from Sweetspot Audio?

 

[Joffy1780]

Give him a chance, mate

 

[peniku8]

I've been in contact with Sascha from Sweetspot audio after I randomly came across one of his listings when looking for used products.
He seems like a nice guy and I've talked about this review as well and his main issue with it was that it's undocumented which version of the 2x4HD was tested by Amir (I guess they switched chips after the AKM fire like many other manufacturers, so there are two versions of it now). He also wasn't happy with whatever PSU Amir used for his testing and that it should be 'obvious' that these tests should only be carried out with linear power supplies and what not. His remark on Amir's findings were that it's "not even possible" for his unit to measure worse because he uses higher quality parts.
He offered to mod my unit for free if I provide him with measurements of it, but in the end he stopped replying to my messages so I'm not sure how interested he is in getting any actual data. He also told me he was gonna send two of the units to Gecom for measuring, so that generally indicates that he doesn't measure and makes his mods 'in good faith'.

 

[RicardoMadGello]

Thanks for continuing to expose products which do nothing or even making things worse while charging money. There is a word for those products and such companies ….


Piggy bank panther would have been my vote.

Surely, only the best!

CROG000870 - Cartier Baby Panthère piggy bank - Porcelain - Cartier

 

[rsqt]

I've been in contact with Sascha from Sweetspot audio after I randomly came across one of his listings when looking for used products.
He seems like a nice guy and I've talked about this review as well and his main issue with it was that it's undocumented which version of the 2x4HD was tested by Amir (I guess they switched chips after the AKM fire like many other manufacturers, so there are two versions of it now). He also wasn't happy with whatever PSU Amir used for his testing and that it should be 'obvious' that these tests should only be carried out with linear power supplies and what not. His remark on Amir's findings were that it's "not even possible" for his unit to measure worse because he uses higher quality parts.
He offered to mod my unit for free if I provide him with measurements of it, but in the end he stopped replying to my messages so I'm not sure how interested he is in getting any actual data. He also told me he was gonna send two of the units to Gecom for measuring, so that generally indicates that he doesn't measure and makes his mods 'in good faith'.

I had to do with Sascha from Sweetspot Audio for some years. In the end I got my parts back (some) after years with nothing done or only with half/part of the work done.
The listenings tests he did at home to hear if a modification is audibly better is done with "cheap" speakers where he changed the tweeter (without correctly modifying the crossover), "modified" Thomann T'Amps and so on.
So this review shows "a lot", for a lot of money. Better take the money and buy a better component.
Only my very sad experience.

 

[bachatero]

Has there been any resolution as to why this thing is so much worse than the original?

 

[voodooless]

Has there been any resolution as to why this thing is so much worse than the original?

Dunning Kruger happened: someone thought they were clever enough to mod this thing, and then proceeded with some random shit without actually knowing what they did, let alone measuring the results. In reality they knew little about electronics, RFI or board layout.

And no wonder, this company is a side hussle of a guy that sells motorcycles as his main job:

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