Articles, Reviews and Measurements of Audio Products

So I keep running into companies who send me products with best intentions but miss key aspects that cause me to not recommend. And example is a very nice dongle I recently received that had balanced output but was limited to just 2 volts out. If you don't know, I like to see minimum of 4 volts out from such a port as otherwise, you can find unbalanced dongles at lower cost that do that.

Another example is channel balance issue with had with an AIYIMA amp where there was almost 1 dB differential.

Yet another is expected SINAD for an amplifier. Yes, we don't rate amps on that one number but if SINAD is say, 60 dB, the rest are going to follow.

In many cases decision makers are not knowledgeable in these companies so proudly show me the gear, only then realizing they could have built something better, but didn't.

Note that my focus here is for electronics only. And I am thinking about the fewest key criteria that passes the "acceptable" mark from me, and by implication, from...

This is a review and detailed measurements of the Henry Engineering The Matchbox HD unbalanced to/from balanced active converter. It was kindly drop shipped to me by a member and costs US $250.

While stamped steel, the box is heavy and sturdy which fits the purpose. Trims are provided to adjust levels and internally there is a high-gain mode. Nice to see power supply built-in although the cord is darn thick and heavy for little power this box needs:


For testing I focused on RCA to XLR since many want to hook up amplifiers with unbalanced out to an amplifier with only balanced input.

EDIT: added the reverse conversion measurements as well.

The Matchbox HD Performance Measurement
I hooked up RCA out at 0.83 volts to get...

This is a review and detailed measurements of the NEOHIPO ET30 VU meter and 2 in, 2 out speaker selector. It was sent to me by the company and costs US $160 but is on sale for 20% less on Amazon.

Let me tell you: you are not a hifi nerd if your heart did not melt as mine did the moment I saw the gorgeous, large VU meters!!! What's more, they are lit via very uniform lighting RGB LEDs. Above is set to yellow-green but you can change them to almost any color with the middle knob. Each color was stunning in how intense and beautiful the shades were.

The good story doesn't end there. There is acceleration with damped return. You set the range for the VU meters with the left knob. The right knob programs how fast they act, from very slow on far left to quite nimble (for their size).

The case is made out of solid metal giving the unit a nice feel and...

This is a complementary review of Sound Devices MixPre-3 II digital audio recorder and mixer.



@amirm has done a first review (you may find it here), but it appears he measured the device in "Basic" mode only.
This mode has some strong limitations.
One of those being that the limiters (there are several layers of them) are always active.

I will now have a look at the Advanced mode.

I rented the device for the week-end (45€) to measure it.

Ergonomy

One thing you may not realize immediately when looking at a photo of the device is how tiny it actually is.
Look at it on top of the RME UCX II.
The UCX II is half 19" rack width.

The device itself feels solid and quite heavy for its size.
A rubber-like coating prevents it to slip from any surface...

This is a review and detailed measurements of the Weiss DAC205. It was kindly sent to me and appears to be recently discontinued. Original price (I think) was around $2,600.

While the case looks pretty basic, it is fine with me. Sure, for that kind of money, you would want it to have an OLED display with every feature imaginable but you are not going to get that. Nor will you be able to connect using USB as the only inputs are Toslink and Coax. Back side shows the typical connections:

Again, for this price I expect to see built-in power supply but an external switcher is provided.

The two switches provide different levels of output although none are compliant with our standard as you see below in measurements.

Weiss DAC205 XLR Measurements
The closest I could get to 4 volt was 2.4 volts:


This is quite competent performance although very shy of state of the art...

This is a review and detailed measurements of the Marantz Cinema 70s home theater Audio/Video Receiver (AVR). It was kindly drop shipped by a member and costs US $1,200.

The 70s sports the new industrial design of Marantz AV products which I very much like. It looks even more attractive in this slim package. The display is not very informative but I can see it fitting the style now better than it ever did. Back panel shows a simpler layout which again, I prefer:


Many of us want a compact setup to go with our flat panel TVs or alternatively serve as our main music and TV/video sound and this is all we need really.

I updated the 70s to latest firmware which took about 10 minutes but otherwise was effortless...

Measurement Conditions Explanation And Chart Interpretation Of Cuckoo Studio Review​

Welcome to Cuckoo Studio Review. I'm Anzol，this is a program dedicated to reviewing audio products from the perspective of a mixing engineer.
We've received the STAX SR-5 from Sandaimao. I'd like to thank him for his support of the channel.Let's take a look at how these headphones perform.



The STAX SR-5 was released in 1975, nearly half a century ago. Those familiar with the brand might know that the SR-1 was their inaugural model in 1960, and while the subsequent SR-2 and SR-3 had detail changes, They retained the vintage "big scissor" headband design. The most significant change in the SR-5, based on the SR-3, is here: the...

This is a review and detailed measurements of the 3e Audio 480-1-29A, TPA3255 based class D amplifier module. It was sent to me by the company in a reference design for ease of testing:

The module is the PCB to the right and costs US 89.99 from company Aliexpress store. This is the mono version (I reviewed the stereo version earlier). The differentiation is pulling the required class D filter into the amplifier feedback loop (PFFB) and with it, essentially eliminate the effect of speaker load on frequency response. Low cost implementations lack this which can make the tonality somewhat variable. Other optimizations are done to extract better performance out of the TI TPA3255 class D amplifier module.

When swapping the stereo module for mono above, I was...

As some of you know, I presented a paper at this years Audio Engineering Society on measuring over 450 DACs. All the tests were detailed in the paper together with motivations and learnings from the multi-year project. The paper is only available for a fee (link below). AES asked for a short presentation at the conference itself. In this video, I go through that presentation with more detail than I intended to cover at the conference. This way, you get a bit more flavor of what I had written in the paper.


Here is the link to the paper and where you can download it: https://www.aes.org/e-lib/browse.cfm?elib=22278

It is free for members and costs $33 otherwise.

This is a review and detailed measurements of the WiiM Pro Plus streamer, DAC and preamplifier with Bluetooth support. It was sent to me by the company and costs US $219.

While the case is plastic, it still "looks the part" as the Brits would say relative to other more famous brands of streamers. I was pleasantly surprised to see support for analog input:


There is both Toslink in and out and even trigger support (for automation/turning on downstream devices). As usual, you need to download an App to get access to full set of functionality. Upon running said app, I was once again pleasantly surprised in it instantly finding the streamer. It asked me if I wanted to upgrade and I said yes. It took about 6 minutes which was rather long...