USB B/B - Keytar to Keyboard

[Kebbel]

I have a Yamaha Sonogenic 300 Keytar and a Yamaha DGX-670 keyboard. Both have USB MIDI ports, not 5-Pin MIDI ports. I bought a USB B/B cable (device plugs on both ends) from Amazon to connect the two devices. I was hoping I could access the keyboard voices from the keytar via the USB B/B cable. Nothing.
(1) Is there some trick I can do to get the cable to work?
(2) If not, what would people use a USB B/B cable for?

 

[Gourockian]

(2) If not, what would people use a USB B/B cable for?

I have two USB B/B cables with plugs at each end but they are both different. One is just a straight mirror image of each socket so that when I check it with a meter, each 'pin' connects to the same number on the opposite end. To be honest, I'm not sure how this would be used.
The second one is called a Patch cable and is labelled as such. Pin 2 connects to 3 at the opposite end and vice versa. They are used to connect two computers together for transferring data. Pins 1 & 4 are for the 5v power supply. You can also get B/B cables where one end is a B plug and the other is a B socket and is used as an extension.

 

[Kebbel]

I wrote the cable company that supplied the cable to Amazon to ask them what that cable is actually used for. I also asked if there was a variation of the device-to-device cable that might solve my problem.

 

[anotherscott]

I have a Yamaha Sonogenic 300 Keytar and a Yamaha DGX-670 keyboard. Both have USB MIDI ports, not 5-Pin MIDI ports. I bought a USB B/B cable (device plugs on both ends) from Amazon to connect the two devices. I was hoping I could access the keyboard voices from the keytar via the USB B/B cable. Nothing.
(1) Is there some trick I can do to get the cable to work?
(2) If not, what would people use a USB B/B cable for?

USB is not a peer-to-peer system like 5-pin MIDI. There are host or "master" devices (most often, computers of some sort), and peripheral or "slave" devices. Your keyboards can't connect to each other directly, but must be connected via a host.

In the early days of USB, it was simple... the USB-A connector was on the host and the USB-B connector was on the peripheral devices. And they didn't make the two connectors different to make things difficult... they did it to prevent people from doing things like you're trying to do, things that couldn't possibly work. Something with an A connector could connect only to something with a B connector, and vice versa. Things later got more complicated with USB OTG and USB-C, since something with a given connector could function as either host or slave device, but A and B remain pretty straightforward. The only way you can connect those two keyboards together is through a host device... e.g. computer, tablet, smartphone, or standalone host like this one.

There are a handful of keyboards that include USB host functions, so that you can indeed plug another USB controller into them, but even then, they would supply USB-A connectors for that purpose. You'll find that functionality on MODX/Montage, Kronos/Nautilus, and Kurzweil PC4/K2700, for example. (Your DGX-670 does have a USB-A connection on it as well, but as the manual says, its use is limited to flash drives and their wireless adapter.)

As for why a B-to-B cable exists... apparently there are some "non-standard" uses. I looked up one on Amazon, and the description said "The cable is good for those rare applications where Type-B connection on both end is needed. Like Automotive Sync Cable Replacement."

 

[TedS]

You probably need some kind of out-board USB-to-MIDI host. (Google "Kenton USB midi host".) I have a sinking feeling that you'll need to swap your keytar for one with 5-pin MIDI. If you get it to work, let us know.

 

[Kebbel]

USB is not a peer-to-peer system like 5-pin MIDI. There are host or "master" devices (most often, computers of some sort), and peripheral or "slave" devices. Your keyboards can't connect to each other directly, but must be connected via a host.

In the early days of USB, it was simple... the USB-A connector was on the host and the USB-B connector was on the peripheral devices. And they didn't make the two connectors different to make things difficult... they did it to prevent people from doing things like you're trying to do, things that couldn't possibly work. Something with an A connector could connect only to something with a B connector, and vice versa. Things later got more complicated with USB OTG and USB-C, since something with a given connector could function as either host or slave device, but A and B remain pretty straightforward. The only way you can connect those two keyboards together is through a host device... e.g. computer, tablet, smartphone, or standalone host like this one.

There are a handful of keyboards that include USB host functions, so that you can indeed plug another USB controller into them, but even then, they would supply USB-A connectors for that purpose. You'll find that functionality on MODX/Montage, Kronos/Nautilus, and Kurzweil PC4/K2700, for example. (Your DGX-670 does have a USB-A connection on it as well, but as the manual says, its use is limited to flash drives and their wireless adapter.)

As for why a B-to-B cable exists... apparently there are some "non-standard" uses. I looked up one on Amazon, and the description said "The cable is good for those rare applications where Type-B connection on both end is needed. Like Automotive Sync Cable Replacement."

I actually contacted the company that supplied Amazon with the USB B/B cable. They graciously explained— in different words – what you said about my connecting a keytar and keyboard and also explained the B/B cable usage: “It is primarily found in specialized, legacy, or proprietary setups (like some KVM switches, pass-through panels, or industrial gear).”

 

[Kebbel]

You probably need some kind of out-board USB-to-MIDI host. (Google "Kenton USB midi host".) I have a sinking feeling that you'll need to swap your keytar for one with 5-pin MIDI. If you get it to work, let us know.

 

[Kebbel]

The vendor— cablesonline.com – graciously took time to explain in detail why it would not work. I did buy a host a few weeks ago, but was hoping I could solve the problem with a single cable instead of dragging along other piece of hardware. I now have a much better understanding of why that Host is necessary and what it does now.

 

[Gourockian]

The vendor— cablesonline.com – graciously took time to explain in detail why it would not work.

I, for one, would be interested if you were able to share the detailed information you received as it may help with a small project. I've started to modify a couple of usb cables I had lying around, so that I'll have a B plug at each end. It will be wired up for data only - pins 1 & 4 will be disconnected as I don't want to power anything with it.

 

[Kebbel]

This is the email. I can’t tell you how much I appreciated a cablesonline.com representative taking his time to answer my question in such detail.

Hi John,
While a USB Type-B male-to-male cable might look like just another USB cable, its use cases are quite narrow. It is primarily found in specialized, legacy, or proprietary setups (like some KVM switches, pass-through panels, or industrial gear).
Both the SHS (Sonogenic) series keytar and the PSR‑E353 keyboard present themselves as “USB Device” ports, and USB Device-to-USB Device connections cannot talk to each other without a proper USB Host in between. For reference:

• USB Host: A USB host device (typically a computer) is responsible for controlling and managing communication on the USB bus. It initiates data transfers and provides power to connected devices.
• USB Device: A USB device (like a printer, keyboard, or MIDI instrument) responds to requests from the host and cannot initiate communication on its own.

If your goal is truly just one cable going directly from the Sonogenic to the PSR-E353, it is important to know that no such single direct cable can accomplish the task; the USB spec requires a host, which neither instrument provides.
You need a USB MIDI interface to act as the necessary intermediary. This interface provides the correct ports (5-pin DIN MIDI and USB) and the necessary circuitry to translate between the standard MIDI signals and the USB data format. It essentially acts as a USB host for the keytar and communicates with the keyboard using standard USB MIDI protocols.

 

[Gourockian]

I have two USB B/B cables with plugs at each end but they are both different. One is just a straight mirror image of each socket so that when I check it with a meter, each 'pin' connects to the same number on the opposite end. To be honest, I'm not sure how this would be used.
The second one is called a Patch cable and is labelled as such. Pin 2 connects to 3 at the opposite end and vice versa. They are used to connect two computers together for transferring data. Pins 1 & 4 are for the 5v power supply. You can also get B/B cables where one end is a B plug and the other is a B socket and is used as an extension.

Correction - I have just discovered that for many years what I have thought was a USB B plug is actually USB A (the flat one). So the above information is incorrect and refers to A - A cables and hopefully has not confused anyone else. It proves the wisdom of double-checking your source of information. This site gives further details: https://www.reference.com/science-technology/ultimate-guide-different-usb-connector-types-uses

 

[Gourockian]

This is the email. I can’t tell you how much I appreciated a cablesonline.com representative taking his time to answer my question in such detail.

Hi John,
While a USB Type-B male-to-male cable might look like just another USB cable, its use cases are quite narrow. It is primarily found in specialized, legacy, or proprietary setups (like some KVM switches, pass-through panels, or industrial gear).
Both the SHS (Sonogenic) series keytar and the PSR‑E353 keyboard present themselves as “USB Device” ports, and USB Device-to-USB Device connections cannot talk to each other without a proper USB Host in between. For reference:

• USB Host: A USB host device (typically a computer) is responsible for controlling and managing communication on the USB bus. It initiates data transfers and provides power to connected devices.
• USB Device: A USB device (like a printer, keyboard, or MIDI instrument) responds to requests from the host and cannot initiate communication on its own.

If your goal is truly just one cable going directly from the Sonogenic to the PSR-E353, it is important to know that no such single direct cable can accomplish the task; the USB spec requires a host, which neither instrument provides.
You need a USB MIDI interface to act as the necessary intermediary. This interface provides the correct ports (5-pin DIN MIDI and USB) and the necessary circuitry to translate between the standard MIDI signals and the USB data format. It essentially acts as a USB host for the keytar and communicates with the keyboard using standard USB MIDI protocols.

Thanks. That certainly is very useful and should help many of us on the forum. As you'll see from my last post, I didn't even have my A and B terminology right - duh!