The Audio Science Review (ASR) approach to reviewing wines.

@samureyex 

Think you may have intended your post referencing the Dave for someone else.  I don’t have one.

Regarding your post about the Puritan, you left out what mattered in Amir’s conclusions, which contained no inconsistencies.   Here’s the full conclusion: 

“Conclusions
As you see, I have run a number of tests to give the PSM156 ample opportunity to show it can do something to improve audio but it can't even move the dial one hair. There is no indication or logic that would tell us that it can make an audible improvement. Yet the company says this in the feature list of this product:
 

None of these things is observed in the measurements. 

The device however seems to have real filtering in there as opposed to toy implementation we see in other audio devices. So if you have audible mains related interference that is above a few hundred Hertz, then the PSM156 may have an effect.

As an audio fidelity improvement device, I can't recommend the Puritan Audio PSM156.  As a mains filter in general, it seems to be well built and does a far better job than typical consumer gear sold for this purpose.”

@oberoniaomnia

If you can not hear the difference between the Topping and the Holo May, then I am pleased for you as you do not need to spend more money to get far better sound.
I, on the other hand, think Topping sounds really harsh in the mid level, particularly with female voices. I found it grating after 20 minutes. As I listen to a lot of classical music as opposed to doof doof, there was no way that I would ever buy a Topping.
I am glad yours is still operating. You are aware of the poor quality control that even many ASR members complain about?

@laoman His (oberoniaomnia) post just proves ASR measurements make no sense. 99% of R2R Dacs measure terrible vs the Delta-Sigma Topping dacs.

For him to even say the Topping and Holo May are more or less equal is just wild. Because the measurements wouldn’t support his statement. Keep in mind how good his Topping D50 v.3 measures. It should on paper, poop all over the Holo May.

I’ve previously stated the Topping D90se (previous Topping flagship and a measurement beast) is subjectively bad.

1) Small soundstage

2) Very poor actual dynamic range. Let’s say you have 10 different sound in the Loud range, 1-10. The Topping can only do 5-6-7 for all 10. The same for problem for soft notes.

3) Poor spaciousness. Lack of air and space between instruments. The small soundstage makes it worse.

4) A very homogenized and boring sound. Because of #1 #2 and #3, Most instruments and notes have similar loudness, It just sounds very similar tracks after tracks. At the end of the listening session It would feel like 1 very long track.

5) Flat dimensionality. Clarity is high but transparency is low. Everything is upfront,

Compared it to my old Anedio D2 dac ($1,200) at the time. The Anedio is leaps better in every aspect, except vocal’s warmth. If I didn’t pay for the Topping myself I would’ve thought it was a $300 dac. All of these are subjectively bad traits in audio. Congrats to D90se for being a measurement beast and sounding the way it does.

I don’t see the purpose of ASR existing anymore. If you believe in ASR’s measurements, You should only buy Topping products. Get their dacs, amps, and preamps.

There is no point in measuring X products. Just get a Topping and be done. Which Toppings don’t matter either. 123 sinad is not going to make a difference vs 124 sinad.

Buy Toppings, Buy Benchmark, Buy anything that Bruno puts out. These 3 are going to put out SOTA measurement products.

@mdalton I was intrigued by your exerts from the PSM156 review in ASR so I read it. My suspicion was confirmed, Amir tested the device with one piece of hifi gear attached at a time. My understanding is that higher end power conditioners have several functions: to supply non limiting current to a number of devices simultaneously, to filter noise that may be in the AC supply line, either coming through the mains at the breaker or imparted to the line between the breaker and the outlet, reduce noise in AC lines emanating from the attached gear or power cables, and potentially surge protection. In Amir’s test, he looked at the performance of the Puratin device with respect to noise in the AC supply line and looked at the measured performance of one piece of attached gear.

Hifi systems in practice can be quite complicated, with multiple devices connected to a power distributor/conditioner. For example, my system is a hybrid 5.1/2.1 home theater and two channel system with four different sources, both digital and analog, a large receiver and a subwoofer. Power from the 20 amp breaker is supplied by a single run of 10 gauge romex to a medical grade outlet. I have a stacked rack arrangement with seven different power cables and fourteen different lower level digital and analog cables all in rather close proximity. Most of my power supply cables are upgraded except for an old Blu-ray player and a vintage turntable which have attached “lamp cord”. The receiver is plugged directly into the wall and everything else is plugged into a power conditioner/distributor. I suggest the opportunity for some electrical noise generated in digital devices or power supplies to affect other devices or cables nearby is significant.

My system definitely benefitted by replacing a sturdy but simple non-surge protected power strip with a more substantial power conditioner/distributor, and by again by replacing the supply cable from the wall to the conditioner/distributor with a better cable (the single biggest cable improvement I have made in over 20 years of tinkering). I do not know if this benefit of adding a new conditioner/distributor and supply cable had to do with less current limitation due to higher gauge internal and external wiring, cleaning up AC from the mains, or reducing the impact of noise generated in the attached equipment.

What I do find challenging is a review of a power conditioner designed in part to tame electrical noise in a system of attached components by connecting and assessing one device at a time. The review of the Puritan Audio PSM156, perhaps more than any other on ASR, points to the weakness of the reductionist approach for evaluating products that were designed to reduce noise and improve the sound of a complex system by looking at one variable in isolation. To strain the oft used audio-car analogy, this is like saying “I tested the Corvette on the skidpad and while it did what the manufacturer claims I cannot recommend it for driving in traffic”. This also reinforces the need to test equipment in your system in your room with your ears. No two circumstances are alike, and as always, YMMV.

kn