As my acoustic preferences have evolved with a few years in this hobby, I have come to realize that your average PC makes for a pretty lousy source component. It’s full of electrical noise and (for many) only has 1 output option. The noise laden USB port.
I have been a USB “denier” for a long time. I firmly believed that “bits are bits” and that it did not matter how the bits and bytes got where they needed to go. It was the job of the DAC to deal with whatever crappy signal it was fed and convert the stream of ones and zeros into analog sweetness.
The Intona USB isolator changed my perception about USB “decrapifiers”.
(Thank you Schiit Audio for creating a lasting moniker for an entire range of products) I have a DAC that just didn’t seem to live up to its potential using a “straight USB” connection. Thanks to Tim @
Kitsune HiFi, I had a chance to evaluate an Intona. It made a significant difference in my system. I was impressed with the improvements in soundstage and clarity. The veil that covered some recordings felt lifted.
I was reminded of that famous quote, “
The proof of the pudding is in the eating”.
A USB gadget that really makes an audible difference!
What is it?
The Intona high-speed Isolator is nifty USB powered circuit board stuffed into an oversized butt ugly plastic box.
The isolator is connected to your PC via a standard USB A-to-B cable and sits between your computer and your DAC. (or whatever USB device needs “decrapification”) It provides galvanic isolation to the USB bus, repacketizes and provides clean power to your USB device. It blocks the noise coming out of your computer by isolating the both the data and power. The Isolator can operate at full USB bandwidth of 480MBit/s and works perfectly with 192kHz PCM and DSD content.
There are two versions of the Intona USB Isolator – both do the exact same thing. The “base” model retails for around $230. The difference is that the ~$320 Industrial version is built to tighter tolerances with a “bill of materials” where component substitution is not permitted.
The Intona was not designed for audio use, but quickly gained acceptance among audiophiles. It was designed for industrial and laboratory applications requiring a low noise floor and low jitter.
I was particularly intrigued by the photo below. You can see how the two PCB boards (input and output) are completely separate. They are only joined by the digital isolator chips.
Feature List
According to the
manufacturers website, the Intona provides the following features:
- Provides galvanic isolation to the USB bus
- Compliant to USB 2.0 Hi-Speed (480 MBit/s)
- Isolation withstands up to 2.5kVRMS
- Works out of the box, no drivers needed
- Transparent to host and device
- No additional round-trip latency
- Powered by USB bus, no separate power supply
- Ultra-quiet power rail isolation, linear regulation
While browsing the Intona frequently asked questions; I found two interesting graphs that compare a 1k signal with and without the Intona isolator. You can see that the noise floor is reduced dramatically.
Of particular interest is how the 8kHz spike commonly associated with packet noise is suppressed. That makes an audible difference and is one of the metrics for audiophiles.
Installation
Since the Intona does not require an external power supply and does not require a device driver on your PC - installation is about as easy as it gets. It is truly plug-and-play.
The Intona will require two USB cables; a standard A-to-B cable from your computer to the Intona and another cable from the Intona to your USB device. The “dirty side” cable from your computer to the input of the Intona can be any generic USB cable of an appropriate length. I am currently using a 6” Belkin USB “daisy chain” cable to from my laptop to the Intona. It was less than
$5 from Amazon.
On the “clean side” of the Intona, I use a quality AudioQuest Carbon
http://audioquest.com/usb-digital-audio/carbon USB cable from the Intona’s output to the input of my DAC. Many Intona users keep the “clean side” cable as short as possible to minimize the chances of stray RF noise getting picked up enroute to their USB device.
How Does It Sound?
To test the benefits of the Intona I queued up a couple of familiar tracks. I plugged my DAC into the computer with nothing else in the signal path. Then I compared the same track played through the Intona.
First up was Alison Krauss’s “
Forget About It”. Without the Intona the delicate opening guitar work is present, but felt a little distant. The sound of the shaker was the same from one beat to the next. Alison’s vocals were warm, but weren’t particularly separate from the rest of the band.
Plugging the Intona into the signal path made a significant difference. There was a little more air in Alison’s vocals. The soundstage widened and I got a better mental image of the placement of guitars, piano and percussion. Detail was certainly improved. The sound of the shaker was distinct – not monotonous. Cymbals started to shimmer and decay into the ether correctly.
I think this is a good point in the review to remind readers that these changes aren’t huge night/day differences. One can certainly enjoy the music without an Intona. However, as my musical preferences have evolved, my ears are keen to notice the improvements in timbre and soundstage that the Intona brought out of my system. To me, it’s the difference between a good sounding system and a great sounding system.
Rebecca Pidgeon’s performance of “
You Got Me” is one of my favorite test tracks; not just for Rebecca’s amazing voice, but for the two acoustic guitars and simple percussion. I feel that Dr. Chesky’s recordings are among some of the best mastered albums and sound amazing on a quality HeadFi system. Without the Intona I found the acoustic guitar on the left to lack a little detail. With the Intona plugged in, the detail that I felt was missing emerged. The background vocals now stood apart from Rebecca’s voice – a great example of detail and separation.
One of the most common USB complaints is “packet noise” which is centered around the 8kHz frequency. I hear this anomaly in the reproduction of cymbals. I’ve characterized this as hearing cymbals that “crash” instead of “shimmer” – where roll-off and decay sound unnatural. I have used the Queen/David Bowie hit “
Under Pressure” to test reproduction of cymbals. I have four different versions of this song. To me; the best sounding version comes from the
2011 remastered Greatest Hits album. I found the Intona to really shine on this track as the decay of the cymbals felt much more realistic.
Your Mileage May Vary
So will the Intona work wonders on your system? That depends on the quality of your USB source and the capabilities of your USB device.
I recently reviewed two DACs. The Benchmark DAC3 and the Holo Spring DAC. Both DAC’s were connected to my 4 year old Windoze 10 laptop. The Benchmark DAC3 sounded amazing right out of the box. The Holo Spring sounded “good”, but it was pretty clear to me that something was missing. The Intona provided the extra clarity that helped me get the most out of the Holo. I was left with the impression that the USB implementation in the Benchmark did a better job handling a poor quality, noisy USB signal from my laptop. The Intona helped up the Holo’s game.
Will an Intona make a good DAC sound better? Maybe.
Will an Intona make a bad DAC sound better? Doubtful.
Will make up on an ugly girl make her beautiful? No
In my experience with the Intona, I found that it improved the soundstage on most recordings. It improved separation between instruments and vocals. The timbre
(not timber) of acoustic guitars came through where it had been lost. Cymbals shimmered and decayed correctly instead of just crashing.
Overall, I was very happy with the improvements that the Intona brought to my system.
Will you get the same benefits with an Intona in your system? Maybe. Maybe Not. That will depend a lot on the quality of your source and the quality of the downstream components. Some components will exhibit more noticeable improvements than others. YMMV.
That said, I would recommend that you try one out for yourself.
I think the Intona can be an important tweak to help wring additional performance from your USB system.
