This is a review and detailed measurements of the miniDSP 2x4 HD as is, and as modified by German company sweetspot-audio. Later version was kindly provided by a member and costs US $191 (EUR 175) on top of the cost of the 2x4 HD ($225).
As you see, the main indication that the 2x4HD has been modified is their sticker. This is what the company says they modified:
Scope of modification:
Total changes: 21
The 2x4 HD was one of the earliest measurements I had made with my older analyzer. So let's first update that with a handful of new measurements.
miniDSP 2x4 HD Measurements
We start with our dashboard:
We are just there as far as performance (all tests use Toslink input), clearing the 16-bit audio hurdle by a hair. Such is the case with dynamic range as well:
Jitter test shows some harmless interference:
IMD sweep shows that noise floor could be lower:
Wideband THD+N vs frequency shows rather poor performance:
It could be due to filtering (did not measure).
miniDSP 2x4 HD with sweetspot-audio mod Measurements
Note: I used the US power supply that my minidsp came with. The one supplied has the same rating but has European plug. I don't think this is something that is upgraded.
Let's go back to our dashboard:
Well, this is not good. We lost 6 dB of SINAD performance which we could ill afford. The cause is increased noise:
Same story continues through the rest of measurements:
Clearly there is no reduction in noise or distortion as company claims.
Edit: additional tests for analog in/out
Analog In/Analog Out Measurements
As requested, here are the tests with analog input and output. Let's start with the dashboard of the stock unit:
Now the modded version:
The mod once again degrades performance especially in noise department:
You are losing a full bit of dynamic range you can ill afford. Fortunately frequency response is intact:
The degradation is across the full input/output levels:
Conclusions
Focusing on sweetspot-audio modifications, seems like you are paying a lot of money (almost the cost of 2x4 HD) only to get worse performance! Owner has indicated that he measures. If so, very strange to get the results we are seeing.
The 2x4 HD seems to have just good enough performance. Company makes higher end products with much better performance so if that is what you want, getting one of those would be a better bet than going with the above mod.
Needless to say, I can't recommend the sweetspot-audio modifications for miniDSP 2x4 HD.
------------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
As you see, the main indication that the 2x4HD has been modified is their sticker. This is what the company says they modified:
Scope of modification:
- Improvement 12v DC input voltage
- Improvement entrance level
- Improvement output stage
- Replacement of all operational amplifiers
- RFI measures
- Reducing the noise floor
- Distortion Reduction (THD)
Total changes: 21
The 2x4 HD was one of the earliest measurements I had made with my older analyzer. So let's first update that with a handful of new measurements.
miniDSP 2x4 HD Measurements
We start with our dashboard:
We are just there as far as performance (all tests use Toslink input), clearing the 16-bit audio hurdle by a hair. Such is the case with dynamic range as well:
Jitter test shows some harmless interference:
IMD sweep shows that noise floor could be lower:
Wideband THD+N vs frequency shows rather poor performance:
It could be due to filtering (did not measure).
miniDSP 2x4 HD with sweetspot-audio mod Measurements
Note: I used the US power supply that my minidsp came with. The one supplied has the same rating but has European plug. I don't think this is something that is upgraded.
Let's go back to our dashboard:
Well, this is not good. We lost 6 dB of SINAD performance which we could ill afford. The cause is increased noise:
Same story continues through the rest of measurements:
Clearly there is no reduction in noise or distortion as company claims.
Edit: additional tests for analog in/out
Analog In/Analog Out Measurements
As requested, here are the tests with analog input and output. Let's start with the dashboard of the stock unit:
Now the modded version:
The mod once again degrades performance especially in noise department:
You are losing a full bit of dynamic range you can ill afford. Fortunately frequency response is intact:
The degradation is across the full input/output levels:
Conclusions
Focusing on sweetspot-audio modifications, seems like you are paying a lot of money (almost the cost of 2x4 HD) only to get worse performance! Owner has indicated that he measures. If so, very strange to get the results we are seeing.
The 2x4 HD seems to have just good enough performance. Company makes higher end products with much better performance so if that is what you want, getting one of those would be a better bet than going with the above mod.
Needless to say, I can't recommend the sweetspot-audio modifications for miniDSP 2x4 HD.
------------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
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