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General => Dodgy Technology => Topic started by: JonHendry on August 31, 2018, 02:56:43 pm

Title: Sketchy claim from audiophoole brand Audioquest
Post by: JonHendry on August 31, 2018, 02:56:43 pm
So Audioquest, of the overpriced magic ethernet and HDMI cables, has a USB DAC called the Dragonfly https://www.audioquest.com/dacs/dragonfly/dragonfly-red (https://www.audioquest.com/dacs/dragonfly/dragonfly-red)

Among the marketing spiel for it is this bit, which I find hard to believe:

Quote
AudioQuest and DragonFly designer Gordon Rankin worked alongside Microchip Technology to develop a new high-performance, full-speed USB microcontroller solution that delivers improved signal-to-noise ratio and significantly lower power consumption. Drawing 77% less current than the previous microcontroller, the new Microchip PIC32MX microcontroller enables true compatibility with Apple and Android smartphones and tablets. Further, we simply cannot overstate the significance of Gordon Rankin’s contributions to AudioQuest. The new DragonFly models embody many of Gordon’s most innovative, creative, and elegant digital-audio solutions to date.

Is it just me, or does anyone else think Microchip probably didn't need to collaborate with an outfit like Audioquest to design a new microcontroller?

Also, they have a $50 USB noise filter called the "jitterbug":
Quote
DUAL DISCRETE NOISE-DISSIPATION CIRCUITS
Reduces the noise and ringing that plague both the data and power lines of USB ports.
Measurably reduces jitter, unwanted noise currents, and parasitic resonances.
Packet errors are sometimes eliminated completely.
Improves dynamic contrast, warmth, and resolution.

And there's this gem: "Use an additional JitterBug in parallel for improved playback performance."

As in, "plug a second one into the empty USB socket next to the socket you're using for your DAC, which is connected through a Jitterbug."

(https://i.imgur.com/LWQS2R6.png)
And: "Use JitterBug with other locally connected USB devices, such as hard drives, printers, and cameras, to effectively reduce audio interference."

And: "Use JitterBug with USB-enabled network devices, such as routers, NAS devices, and streamers."

Very important to filter that USB port on the router that you're not using.

It's small enough that I wonder if there's anything in it at all.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: glarsson on August 31, 2018, 06:02:33 pm
It could be a capacitor between +5V and ground. Then it would "make sense" to add more devices in other USB ports nearby. :-)
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: gedong on September 01, 2018, 02:57:44 pm
or maybe galvanic isolation ? it's usefull for reducing any EMI / RF.

don't know about jitter though.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: Bud on September 01, 2018, 03:09:27 pm
PIC32MX is a general purpose type microcontroller family and was introduced quite a few years ago.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: NiHaoMike on September 01, 2018, 10:58:34 pm
I'm surprised they didn't use a PIC32MZ for USB 2.0 and 192kHz support.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: Cyberdragon on September 01, 2018, 11:45:58 pm
I'm surprised they didn't use a PIC32MZ for USB 2.0 and 192kHz support.

No, it has to be USB 1.0 because 2.0 is too fast and stresses your audio electrons. It has to be super slow to properly escort the electons to their destination without discombobulating them. Otherwise , you must have the 10K cable and filter to align and orient the electrons in the right direction so they can be quantum reencabulated. ;D Don't even ask what it takes to reencabulate 3.0...
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: amyk on September 03, 2018, 08:13:48 am
It could be a capacitor between +5V and ground. Then it would "make sense" to add more devices in other USB ports nearby. :-)
Yes, I suspect they're just bulk decoupling caps. Not true snake-oil but probably not much benefit either. Weird "power filtering" products have been around for many years:

https://www.ixbt.com/news/hard/index.shtml?10/66/54 (https://www.ixbt.com/news/hard/index.shtml?10/66/54)

I suspect they will show an effect only if your existing filter caps are already too dried-out to be of much use.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: ebastler on September 03, 2018, 08:53:42 pm
Among the marketing spiel for it is this bit, which I find hard to believe:

Quote
AudioQuest and DragonFly designer Gordon Rankin worked alongside Microchip Technology to develop a new high-performance, full-speed USB microcontroller solution that delivers improved signal-to-noise ratio and significantly lower power consumption. Drawing 77% less current than the previous microcontroller, the new Microchip PIC32MX microcontroller enables true compatibility with Apple and Android smartphones and tablets. Further, we simply cannot overstate the significance of Gordon Rankin’s contributions to AudioQuest. The new DragonFly models embody many of Gordon’s most innovative, creative, and elegant digital-audio solutions to date.

Is it just me, or does anyone else think Microchip probably didn't need to collaborate with an outfit like Audioquest to design a new microcontroller?

If you read carefully, the quote does not say that Microchip got any input from Gordon Rankin and Audioquest. Gordon worked "alongside Microchip", which seems to mean that he used their new chip in his circuit design. The new PIC draws 77% less current (but Gordon presumably had nothing to do with that), and Gordon made "significant contributions to AudioQuest" (but probably none to Microchip).

A nice example of marketing weasels at work...
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: newbrain on September 03, 2018, 10:31:05 pm
It could be a capacitor between +5V and ground. Then it would "make sense" to add more devices in other USB ports nearby. :-)
Yes, I suspect they're just bulk decoupling caps. Not true snake-oil but probably not much benefit either. Weird "power filtering" products have been around for many years:

https://www.ixbt.com/news/hard/index.shtml?10/66/54 (https://www.ixbt.com/news/hard/index.shtml?10/66/54)

I suspect they will show an effect only if your existing filter caps are already too dried-out to be of much use.
L(?)C decoupling on the power lines and a common mode choke on the data lines (https://www.stereophile.com/images/915aqjit.2.jpg).

As the product is not new, there's discussion aplenty on it online.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: Domagoj T on September 04, 2018, 04:23:58 pm
Among the marketing spiel for it is this bit, which I find hard to believe:

Quote
AudioQuest and DragonFly designer Gordon Rankin worked alongside Microchip Technology to develop a new high-performance, full-speed USB microcontroller solution that delivers improved signal-to-noise ratio and significantly lower power consumption. Drawing 77% less current than the previous microcontroller, the new Microchip PIC32MX microcontroller enables true compatibility with Apple and Android smartphones and tablets. Further, we simply cannot overstate the significance of Gordon Rankin’s contributions to AudioQuest. The new DragonFly models embody many of Gordon’s most innovative, creative, and elegant digital-audio solutions to date.

Is it just me, or does anyone else think Microchip probably didn't need to collaborate with an outfit like Audioquest to design a new microcontroller?

If you read carefully, the quote does not say that Microchip got any input from Gordon Rankin and Audioquest. Gordon worked "alongside Microchip", which seems to mean that he used their new chip in his circuit design. The new PIC draws 77% less current (but Gordon presumably had nothing to do with that), and Gordon made "significant contributions to AudioQuest" (but probably none to Microchip).

A nice example of marketing weasels at work...

I wonder if Microchip appreciates being mentioned in this context at all.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: schmitt trigger on September 04, 2018, 05:18:54 pm
It may be a flux capacitor
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: RobK_NL on September 06, 2018, 09:38:32 pm
Quote
Gordon Rankin worked alongside Microchip Technology
I.e. he was so out of his depth that he had to continually pester Microchip's FAE's to get a working product.  :-DD
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: bob225 on September 06, 2018, 09:46:51 pm
Quote
Gordon Rankin worked alongside Microchip Technology to develop a new high-performance, full-speed USB microcontroller solution

Oh yes he printed out the pdf datasheet and had it on his desk  :) ;)
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: Ice-Tea on September 07, 2018, 06:46:51 am
AudioQuest and DragonFly designer Gordon Rankin worked alongside Microchip Technology...

Translation: he posted a question on their forum once.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: Halcyon on September 14, 2018, 01:45:25 pm
AudioQuest and DragonFly designer Gordon Rankin worked alongside Microchip Technology...

Translation: he posted a question on their forum once.

Or he parked his car outside their building, drew a doodle and called it "work".
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: mc172 on September 20, 2018, 08:50:31 am
or maybe galvanic isolation ? it's usefull for reducing any EMI / RF.

don't know about jitter though.

Galvanic isolation is absolutely not useful for reducing EMI!
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: langwadt on September 20, 2018, 09:08:51 am
It could be a capacitor between +5V and ground. Then it would "make sense" to add more devices in other USB ports nearby. :-)

USB 2.0 specification limits capacitance on Vbus to 10uF to limit inrush current
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: glarsson on September 20, 2018, 05:28:06 pm
USB 2.0 specification limits capacitance on Vbus to 10uF to limit inrush current
Facts and specifications will not stop an audiofool company.
Title: Re: Sketchy claim from audiophoole brand Audioquest
Post by: MrMobodies on November 06, 2018, 05:43:19 am
I hear all sorts of noises from different sound cards but they don't seem to bother me that much.
Sometimes it can be quite soothing.