CAD USB Ground Control

[sbnx]

Hello,

A lot of equipment has spare USB ports these days that manufactures use for software updates etc. Pretty much all of my front end gear has these spare ports. I spoke with Scott from CAD at AXPONA about his new USB ground devices. I thought the idea was intriguing. Then I read Roy Gregory's review over on GY8 a few months ago. (https://gy8.eu/review/the-cad-usb-control/) He spoke pretty highly of what these things do. So how could I resist.

I recently purchased several of the CAD USB Ground control devices. These are similar in function to many of the ground noise reduction boxes that have proliforated the market in the past few years. The main difference is that it is simply a dongle that plugs into an open USB port on a piece of equipment. So there is no wire to fuss with and the connection is very direct which should facilitate the noise reducition ability of the device. All I can say is that they work as advertised. Each time I plugged another one in the noise floor of the system dropped farther allowing more and more music to emerge. Let's say you buy one for the current retail of $750 and try it in a few different pieces to decide where you like it best. Then you come along and buy a second, third or forth one. When you plug the second one in the impact is not A+B. The sonic benefit is greater then A+B.

If you try one or two or more I would bet you will like it. But standard disclaimers apply -- YMMV.

 

[PYP]

Hello,

A lot of equipment has spare USB ports these days that manufactures use for software updates etc. Pretty much all of my front end gear has these spare ports. I spoke with Scott from CAD at AXPONA about his new USB ground devices. I thought the idea was intriguing. Then I read Roy Gregory's review over on GY8 a few months ago. (https://gy8.eu/review/the-cad-usb-control/) He spoke pretty highly of what these things do. So how could I resist.

I recently purchased several of the CAD USB Ground control devices. These are similar in function to many of the ground noise reduction boxes that have proliforated the market in the past few years. The main difference is that it is simply a dongle that plugs into an open USB port on a piece of equipment. So there is no wire to fuss with and the connection is very direct which should facilitate the noise reducition ability of the device. All I can say is that they work as advertised. Each time I plugged another one in the noise floor of the system dropped farther allowing more and more music to emerge. Let's say you buy one for the current retail of $750 and try it in a few different pieces to decide where you like it best. Then you come along and buy a second, third or forth one. When you plug the second one in the impact is not A+B. The sonic benefit is greater then A+B.

If you try one or two or more I would bet you will like it. But standard disclaimers apply -- YMMV.

any plans to compare these to the GC1.1?

 

[sbnx]

I have 2 GC1’s, a GCR and a couple Qkores. I like what the usb dongles do.

 

[PYP]

I have 2 GC1’s, a GCR and a couple Qkores. I like what the usb dongles do.

Interesting. Is your DAC connected to the GC1 and also use a USB dongle? Asking because the whole external grounding technology is new to me (have read a few reviews of the GC1 but have no practical experience). Thanks.

 

[sbnx]

Yes. The dac, preamp and server are all plugged into the GCR. There are also usb dongles in the devices as well. Just separate points to remove ground noise.

 

[keithc]

@sbnx thanks for your post. Very interesting device, I normally am a sucker for tweaks but even after speaking w/ Scott (true gentleman), I'm still a healthy skeptic wondering how this thing can work from a EE/physics standpoint. But alas I admit I can't explain for a lot of hi-fi.

Just curious -- since you use an Everest + Typhon, have you tried a direct USB grounding cable into your Shunyata grounding system? If so, was that effective, and how did it compare w/ CAD products?

Thanks.

 

[sbnx]

I can’t fully explain why these types of things work. I have a rough idea but definitely not complete.

i just listen and Judge if whatever makes an improvement ir not. The CAD devices lower the noise floor in a significant way that is obvious for me to hear. This leads to more transparency and dynamics.

i would encourage people to find a dealer who can either demonstrate what it does or sell you one with a 30 day refund period.

 

[PYP]

Yes. The dac, preamp and server are all plugged into the GCR. There are also usb dongles in the devices as well. Just separate points to remove ground noise.

my audio dealer didn't think the dongle would help the Grimm MU1 which has a USB connector for external drives. He did send me a GC1 to try. Have connected to the Grimm via a AES. Will connect SPDIF to the Tambaqui DAC tomorrow.

 

[sbnx]

my audio dealer didn't think the dongle would help the Grimm MU1 which has a USB connector for external drives. He did send me a GC1 to try. Have connected to the Grimm via a AES. Will connect SPDIF to the Tambaqui DAC tomorrow.

"grounding" is a funny thing. Sometimes things improve and sometimes not depending on which connection is used. Did you think the sound improved when the Grimm was plugged into the GC1? Not sure why your dealer thinks the USB dongle won't help the Grimm. Has he actually tried it? You can also get a CAD cable with a USB termination to try going into the CG1. That would tell you if applying "ground" to the USB input will help or not.

 

[PYP]

"grounding" is a funny thing. Sometimes things improve and sometimes not depending on which connection is used. Did you think the sound improved when the Grimm was plugged into the GC1? Not sure why your dealer thinks the USB dongle won't help the Grimm. Has he actually tried it? You can also get a CAD cable with a USB termination to try going into the CG1. That would tell you if applying "ground" to the USB input will help or not.

The GC1 has been connected for only 1 hour to the Grimm. I'll listen tonight to determine any changes. I also have an SPDIF cable to try with the Grimm. Good idea about trying the USB connector. The dealer mentioned all the processing the MU1 does on the USB input as his reason for doubting any improvement. No, I don't think he has tried the dongle. Meanwhile, there is a GC1.1 model too.

The grounding topic is indeed interesting. Shunyata makes two different units. One is a chassis hub (which can also be connected to unused outputs if there is no grounding lug) and a signal hub. It gets rather complicated in complicated setups. For simple setups like mine, they suggest a chassis hub is appropriate. Their hubs have six connections plus one to connect to their power distributors.

 

[sbnx]

PYP, in my experience the effect of plugging in a GC1 (or any grounding thing) is pretty instantaneous. It doesn't have to "burn-in".

Hopefully you have a nice improvement in your sound when you get home.

 

[PYP]

PYP, in my experience the effect of plugging in a GC1 (or any grounding thing) is pretty instantaneous. It doesn't have to "burn-in".

Hopefully you have a nice improvement in your sound when you get home.

I've tried a few combinations of MU1 alone, DAC alone and both. Tried the AES output on the MU1 and the SPDIF input on the MU1. None of the combinations yield a positive difference in my setup. There might have been a slight difference in some frequencies but the band seemed very narrow and I had really listen for it, which isn't the way I listen to music (vs. listening to sounds). Again, in my setup, to my ears and using the connections I used.

 

[luca.pelliccioli]

Yes. The dac, preamp and server are all plugged into the GCR. There are also usb dongles in the devices as well. Just separate points to remove ground noise.

Just installed a USB Control, it immediately lowered the noise floor, making music flowing more relaxed and clear. It works. I also have 2 GC1s.
How have you connected the MSB DAC to the GCR? I’m using on my Premiere the USB Pro module, it means that the only unused input is the BNC (on the same AES/EBU XLR module).

Received also the CAD USB II-R cable to try.

 

[sbnx]

Hello, yes, connect to the ground posts on the power supply.

 

[luca.pelliccioli]

Hello, yes, connect to the ground posts on the power supply.

Thanks, to be sure: the CAD wire spade terminated connected to the Chassis Ground lug of the PowerBase of the DAC. Keeping the metal jumper between the two lugs.

Having the GC1 with only 2 connections available, I‘d use it exclusively for the above described DAC “Earth Ground“ connection, (am I wrong? This is a Earth Ground?). I’m asking so because CAD manual recommends not connecting at the same GC1 unit both “Signal Ground” and “Earth Ground”.

I’d use another GC1 for “Signal Ground“ connection with components like sever or switch, using USB, SPDIF, BNC, RCA unused ports.

 

[sbnx]

You are correct. It is generally not a good idea to connect the signal ground to the earth ground. These grounding devices are funny things. You really just need to experiment and see what sounds best.

Each component is different. Some components have an isolated signal ground. Some do not. If you want to know if this is the case for any given component then take a ohm meter (digital volt meter or other) and touch one lead to the chassis ground (post) and the other lead to the outer ring of an RCA input/output. (You can use some other signal input/output as well. just touch the lead to the ground leg). If you read close to zero ohms then the chassis (earth) and signal grounds are tied together. Probably better than using the chassis lug is to use the ground terminal on the IEC power cord input. More information on this can be found in the Shunyata manual for their Altaira ground box.

 

[luca.pelliccioli]

You are correct. It is generally not a good idea to connect the signal ground to the earth ground. These grounding devices are funny things. You really just need to experiment and see what sounds best.

Each component is different. Some components have an isolated signal ground. Some do not. If you want to know if this is the case for any given component then take a ohm meter (digital volt meter or other) and touch one lead to the chassis ground (post) and the other lead to the outer ring of an RCA input/output. (You can use some other signal input/output as well. just touch the lead to the ground leg). If you read close to zero ohms then the chassis (earth) and signal grounds are tied together. Probably better than using the chassis lug is to use the ground terminal on the IEC power cord input. More information on this can be found in the Shunyata manual for their Altaira ground box.

Thank you I'll give it a try as described above, with the Chassis Ground of the MSB DAC.

Eventually I could connect the second available wire of the GC1 to another component, always using a Earth Ground lug, for instance:
> a conditioner like the Puritan 156 that is feeding the MSB DAC itself (if it makes sense)
or
> a PSU custom made by Sean Jacobs that is feeding the router.

Actually I'm already using 1 of mine GC.1 connected with 1 only wire spade terminated with the Puritan conditioner, and it sounds pretty good.
The real improvement I'm noticing though is thanks to the new USB Ground Control dongle, really really effective lowering the noise floor once inserted into the Statement server.

 

[Backpacker]

I just added the USB control to my system. It’s connected to my streamer and I was surprised how much it improved the sound. Lower noise floor and a more natural, pleasing tone. Scott is definitely on to something here….Great upgrade for the price.

I also have a GC1 connected to signal ground on my streamer and a GC3 connected to chassis ground / shared AC ground.