Articles, Reviews and Measurements of Audio Products

I was looking for a compact audio interface with one mic preamp with software-controlled gain and a balanced stereo output for live shows.
The ESI Maya22 seemed to match my needs pretty spot on, at least I couldn't find anything smaller that fit the bill, so I ordered it and sure enough it showed up at my doorstep today.
As you'll see further into the review, the interface has some fundamental flaws which made me return it. Sadly I had forgotten to take a picture of the unit, so the stock image from the ESI website will have to do:



For the measurements I used a Topping EX5 as signal generator and the Cosmos ADC as input device.
Let's kick things off with the DAC part:

80,5dB SINAD:

Ouch... That's a rough start. At 0dBFS it produced 3,6Vrms unloaded, which dropped to about 2,3V being connected to the low-impedance Cosmos ADC.
-1dBFS (the level of this...

POLL IS NOW CLOSED (thread remains open for analysis and comments)...

This is an updated follow-up poll to my September 2022 one. Was asked to see whether much has changed since then. Also deleted the active or passive options to simplify the poll.

As mentioned previously, the forum software limits the number of choices to 10. A final edit glitch also limited my ability to modify the responses without deleting the entire poll. So, the last couple of responses are out of order.

Thanks for your participation!

P.S.
Casting an intentionally inclusive net, wanted to include home theater and home theaters that are used for music listening. So, if you feel you are limiting your response, you likely should choose the Multiple systems option. For example, I have Amazon Echo speakers, a stereo system and a home theater. Which I listen to primarily is more a matter of convenience, so I fit the Multiple Systems case even though I barely use the home theater for video anymore...

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:

• 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...

This is a review and detailed measurements of the Human Speakers 81 dk. It is on kind loan from a member and costs US $1,270 (kit or finished?).

Everything from the grill to lacquer finish looks gorgeous. Like the hand written notes on the back (and very recent production date):


The grill was stiff and hard to remove so I left it in place. As usual, measurements are performed using Klippel Near-field scanner. I roughly identified center of tweeter through the grill and set it as the acoustic axis.

Company hand builds/modifies its own drivers.

If you are not familiar with my tests, I highly recommend that you watch my video on understanding speaker measurements.

Human Speakers 81 dk Measurements
Let's start with our frequency response measurements:

Ouch. We clearly have design issues around the...

This is a review, listening tests, EQ and detailed measurements of the Hifiman Ananda Stealth V2 open back headphone. It is on kind loan from a member and costs US $399.

It is typical Hifiman large cup configuration that seems to assume you ear are twice as long as they really are! If find the headphone attractive and comfortable to wear.

Let's measure its response using GRAS 45CA driving by Audio Precision APx555 analyzer. If you are new to my headphone measurements, I highly recommend that you watch my video tutorial on headphone measurements.

Hifiman Ananda Stealth V2 Measurements
Let's start with our headphone frequency response measurements in the context of most preferred target response:

It...

Back in 2019, I reviewed the Benchmark AHB2 Stereo Amplifier. I received a second sample from a kind member to update the measurements. Originally the AHB2 cost $3000 but now, $3,500.

As you see, it is a compact but very nice looking amplifier. I appreciate the clipping indicator which seemed accurate in testing. Back panel shows both SpeakOn and traditional binding posts:


In my original testing, I used the SpeakOn connectors as that gave better response than the binding posts. They are directly soldered to the PC Board as opposed to extra wiring. The amplifier is so low distortion and sensitive to load modulation that this...

This is a review and detailed measurements of the XDUOO XQ50 PRO 2 BT receiver and DAC. It was kindly donated by an overseas member and costs US $89.

As you can instantly see, XQ50 Pro 2 has this wonderfully informative display that shows the codec in use (LDAC), sample rate (missing a zero as it should be 41000), bit depth and even the file name of what is playing. Can't tell you how useful this information is. In the process of getting my Samsung to use LDAC, I would constantly see that another codec was being used until I found the right place to change it. For diagnostic purposes alone, this is worth having. Here is the back side:


You have a choice of internal DAC with RCA output or using either Coax or Toslink S/PDIF to an external DAC. Power...

This is a review, listening tests, EQ and detailed measurements of the Tanchjim One In-ear Monitor. It was sent to me by the company and costs US $27.

Unlike many of its competitors, the ONE doesn't attempt to look like fake jewelry and instead, conveys a modern and stylistic design. The diminutive structure likely fits better in many people's ears. The supplied box and tips also look much more proper than recent $20 IEMs I have tested. I like it!

Let's put it on our GRAS 45-CA professional measurement fixture and see how it does. If you are new to these tests, please watch my video to understand headphone measurements.

Tanchjim One IEM Measurements
Let's start with our usual frequency response for the ONE:

We see very good to excellent compliance with our target. I probably should have adjusted the level at a higher frequency to get even...

Marantz CINEMA 70s AVR has been recently reviewed by @amirm here and I had it purchased online a couple of hours prior to the above review to be published on ASR. Also, audio.com.pl had it reviewed earlier as well.


I bought it for improving movies listening experience in an audio surround environment, for its PRE-OUT outputs for all its 7 channels, but also because it was the only AVR with a low height I’ve seen on the market at a reasonable price. I paid for it 646 EUR on amazon.de with free shipping, so it’s an OK price I’d say. I had it...

This is a review, listening tests, EQ and detailed measurements of the HIFIMAN Susvara Planar Magnetic Headphone. It was kindly drop shipped by a member and costs US $6,000.

Owner was advised that the Benchmark AHB2 power amplifier would be the right device to power it so I tested it with that as well as my normal Topping A90 headphone amplifier.

Hifiman aces the design of the Susvara coming in a modern and elegant looking package. It is rather lightweight for its size as well, making it comfortable to wear. The only minor issue there was feeling the strap on my head but otherwise, it was excellent and I almost forgot I was wearing it. You can't see it but the metal strap is rectangular which I am not fond...