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AHB2 vs A21+

archerious

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Anyone have measurements of the A21+? Amir's superb review of the AHB2 is great, and I have fond memories of the Benchmark DAC1, so as a company I'm leaning that way.

Only thing that concerns me is the fact that I'm a POS that seems to like noise.

I'm not loving the D90, I think I'd rather have the less accurate Denafrips Ares II.

I'm worried I'll feel the same way about the AHB2.

Can anyone tell me the sonic/audible differences between the two? Different sound signatures etc?
 

pma

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I measured Halo A21 in January 2019. It was nothing to call home about. All measurements into 4ohm load. Measuring conditions written in the graphs.

a21_100W.png


a21_328W.png


a21_ccif_21V.png


a21_thdfreqr.png

THD vs. frequency
 
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archerious

archerious

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pma

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A21+ is supposed to have a few improved components over the A21 but the Parasounds will probably never measure as good as the Benchmark or good implementations of Class D. However, some people prefer it for its sound signature not as a totally transparent amp which the others would be.

https://www.stereophile.com/content/parasound-halo-21-power-amplifier-measurements

Thanks for posting that, I have not seen this A21+ review yet. The measurements are generally very similar to mine performed on the older A21. However, it seems to me that regarding measurements the A21+, according to Stereophile plots, is a step back. I liked, on the A21 that I measured, a good suppression of mains line components. The A21+ results look worse (to my eyes) and also distortion seems to be higher than that of A21 in my measurements.
 

pma

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any chance you also measured parasound hint?

I had it here, but did not made any meaningful measurements. Subjectively, it was more noisy (worse S/N). You could hear noise and slight hum if the ear was about 50cm from speakers with some 88dB/W/m sensitivity. My qualified guess is that the integrated is worse than A21.

I also measured Parasound P5 preamp. It was quite good, see attached plots.

Parasound P5 preamp measurements

parasound_p5_ccif_L.png

Intermodulation 13+14kHz test

parasound_p5_thdfreq_L.png

THD vs. frequency
 
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archerious

archerious

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AHB2 seems like the king.

Denafrips Thallo is the only other amp I'm considering than the AHB2 and Hypex/Purifi.

It's nice looking but I can't find measurements.
 

vavan

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You could hear noise and slight hum if the ear was about 50cm from speakers with some 88dB/W/m sensitivity
interesting as I never heard any noise/hum from my hint with every speaker I used (heco aurora 1000, polk lsim 705 and currently f208)
 

vavan

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pozz

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A21+ is supposed to have a few improved components over the A21 but the Parasounds will probably never measure as good as the Benchmark or good implementations of Class D. However, some people prefer it for its sound signature not as a totally transparent amp which the others would be.

https://www.stereophile.com/content/parasound-halo-21-power-amplifier-measurements
There's nothing to prefer. The distortion barely reaches -80dB and is mostly H2. IMD results are decent as well and there is little load dependency. It also clips at several hundred watts, which is more than enough power for most.

It would be more accurate to say some people consider the A21 to have a sound signature.

Behind a lot of traditional product preference, especially for established products, is supposition and pretence. Pretending to prefer something everyone else does on some murky basis is as common as pretending to hear something no one else can.

I agree with your comments otherwise.
 

pma

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Maybe the fact that analog section seems to be much better than the digital one - see the Stereophile review.
 

vavan

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SIY

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problem with channel imbalance induced by used Alps pot

This does not seem to appear in the measurements referenced by Pavel.

Presumably, this would be a bit different from unit to unit; depending on which Alps pot was used (they make thousands of different ones), the balance can be quite consistent.
 

vavan

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This does not seem to appear in the measurements referenced by Pavel.

Presumably, this would be a bit different from unit to unit; depending on which Alps pot was used (they make thousands of different ones), the balance can be quite consistent.
I guess so and believe they knew their reasons to replace Alps with resistor ladder volume control in P6/Hint 6
 

Vasr

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Thanks for posting that, I have not seen this A21+ review yet. The measurements are generally very similar to mine performed on the older A21. However, it seems to me that regarding measurements the A21+, according to Stereophile plots, is a step back. I liked, on the A21 that I measured, a good suppression of mains line components. The A21+ results look worse (to my eyes) and also distortion seems to be higher than that of A21 in my measurements.

I don't really know how much of that would be variances of two units measured at different places in different setups but I take your word for it.

I had it here, but did not made any meaningful measurements. Subjectively, it was more noisy (worse S/N). You could hear noise and slight hum if the ear was about 50cm from speakers with some 88dB/W/m sensitivity. My qualified guess is that the integrated is worse than A21.

As far as I know the amp in the older integrated Hint was not the A21 but the lower-end A23 (A23+ in the newer Hint 6). Hint 6 is basically P6 and A23+ in the same chassis.

Here are the measurements for the original Hint.
https://www.stereophile.com/content/parasound-halo-integrated-integrated-amplifier-measurements

The A23 was not considered one of the best efforts at Parasound. They apparently compromised way too much on the components to meet the price target. The A23+ was meant to fix that. But both are a cut below the A21 series.

Here are some measurements
https://www.soundstagenetwork.com/i...er&catid=97:amplifier-measurements&Itemid=154
https://www.soundstagenetwork.com/i...er&catid=97:amplifier-measurements&Itemid=154

The 3 channel A31 is closer to the A21 in design (not the +) measured here
https://www.soundstagenetwork.com/i...er&catid=97:amplifier-measurements&Itemid=154

I don't own any Parasounds but had investigated them earlier for my needs.
 
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