Avoid this MIDI to USB cable

[jimhenry]

A vast majority of the reports of problems connecting a keyboard can be traced to a MIDI to USB cable that looks like these:

adapters1.jpg (27.28 KiB) Viewed 3505 times

They work for some people and not for others. It appears to be either extremely poor quality control or an inability to handle MIDI with a lot of notes being played. If you insist on buying one these cables, count yourself lucky if it works. If it doesn't, trash it and spare us all the effort of figuring out that you have one of these cables and telling you it is junk that cannot be made to work. The E-MU Xmidi cable has proven to be a reliable MIDI to USB cable.

[Nicholas]

More to avoid as of Mar-2018: This new crop of generic adapters (stamped with any brand name you like) seems to be causing users the same kind of inconsistent trouble. I'm guessing they all suffer from the same out-of-spec circuit problems.

moreGenerics.jpg (35.26 KiB) Viewed 10674 times

---

More to avoid as of Dec-2018: Ha! This third batch even mentions "... we released an updated version since Oct-2018, this MIDI to USB cable is compatible with more instrument equipment and computer systems..." as a feature because the 2nd batch was getting such poor reviews. But the new ones still seem to get the same ~25% rate of 1-star reviews, so my guess is that very little was actually fixed.

adapters3.jpg (40.22 KiB) Viewed 3505 times

[jimhenry]

Now we have proof that the problem with the generic cheap MIDI to USB cable is poor quality control. One of my Miditzer users found this web page that shows what was going on inside one of these cables and what it took to make it work:
http://www.arvydas.co.uk/2013/07/cheap- ... -required/

The key point here is that the assembly and quality control of these things is poor. Some will work. Some won't. If you are prepared to trash it or spend time fixing it, then go for it.

Do you feel lucky punk? Well do you?

[Nicholas]

That's hilarious that the board layout actually has the space and pin-outs for the missing components, but that the manufacturer has just been leaving the parts off to cut costs.

It's nice that we can change our story from "sometimes it doesn't work" to "they don't actually follow the MIDI specification". Now that the X-MIDI adapter is back down to the ~$25 range, things are in a better place. For the year or so there when it was $60 for whatever reason, I actually started mulling over finding a circuit designer, board manufacturer, etc. to make some Synthesia-branded adapter that I knew I'd be able to count on.

That's actually analogous to the music store story: when it was hard to find consistently good content, it was time to set about having it made myself. That's easier than hardware though. Trying to make a MIDI adapter is a rabbit hole that goes a lot deeper than I'm comfortable with.

[jimhenry]

I don't think they leave the part out to save cost. I think their assembly and quality control is poor. The boards are probably assembled by automated equipment that doesn't consistently produce fully populated boards, among other errors, and there is no quality control to catch the bad products. That's why you get a lot of positive comments and a lot of negative comments. It's luck of the draw.

UPDATE

I was too hasty in my understanding of the post about fixing this adapter. The PCB provides for both a correct assembly that uses an opto-isolator as called for by the MIDI spec and a cheap assembly that bypasses the opto-isolator with two resistors. As one of the Miditzer users pointed out, the cheap version will work with some, but not all, keyboards. This actually makes matters worse. One can't tell from looking at the cable whether it has the cheap or the correct assembly of the PCB inside.

BOTTOM LINE: This is still a cable to be avoided because it is not a reliable MIDI to USB connection in all circumstances.

[jimhenry]

Now that the X-MIDI adapter is back down to the ~$25 range, things are in a better place. For the year or so there when it was $60 for whatever reason, I actually started mulling over finding a circuit designer, board manufacturer, etc. to make some Synthesia-branded adapter that I knew I'd be able to count on.

Now that we know the generic cable can be assembled to be a MIDI spec compliant cable, you could pursue importing and selling a Synthesia branded cable. It would be a matter of finding a Chinese supplier you trust. They probably will make them with or without the opto-isolator as you care to order them. The unreliable cables probably come from resellers who order the rock bottom cheapest cables without even understanding the difference in assemblies.
http://www.alibaba.com/showroom/usb-midi-cable.html

I think the bigger issue is do you want to get involved with having to handle orders for a physical product?

[Nicholas]

I think the bigger issue is do you want to get involved with having to handle orders for a physical product?

Absolutely not!

I understand that warehousing and fulfillment are not my core competencies, so the best way to handle something like that is to outsource it to someone whose are. Amazon's FBA program is amazing and surprisingly low-cost. To get all of their logistics, customer support, efficiency, convenience, and trust-by-association for a tiny extra fee is a very easy decision.

[jeanluc]

I'm using one of them. I got lucky it works, but the alternative was a 60-80€ converter with no better reviews.

[raynebc]

The MIDISPORT 1x1 has always worked for me and is available in the $30-$40 (US dollar) price range.

[winters]

I have one of these so called "useless" midi adaptors and it works perfectly on all my music apps except synthesia. Does anyone think that is strange?

[kiwi]

I had this one previously with my kurzweil = zero latency
Now i use same than the white picture at the top and i have a slighty delay :/
So the best was this cheap one bought on eBay (hong-kong vendor).

[Nicholas]

I have one of these so called "useless" midi adaptors and it works perfectly on all my music apps except synthesia. Does anyone think that is strange?

I do think that is strange. How is it misbehaving in Synthesia?

[jimhenry]

Here's another site with pictures of the internals of the cheap MIDI-USB cable. Very different board but still an unpopulated spot for the opto-isolator.

http://shiftmore.blogspot.de/2010/01/qu ... r-usb.html

EDIT by Nicholas: And another site with the same: http://www.frank-buss.de/midi/

[winters]

Nicholas, you were asking how my "useless" usb to midi adaptor is misbehaving in Synthesia. Well it just does not work at all. Synthesia does not recognise my korg midi keyboard. I have the "midi designer pro" app and I can control my keyboard parameters from my ipad with this cheap generic adaptor, I have the Magellan app and Nave and Galileo and Arturia iSEM and other apps and they all interact with my midi keyboard, but not Synthesia. Talking about cheap alternatives, I also use a cheap camera connection adaptor in place of the overpriced Apple camera connection kit. This works perfectly as well. the only thing is, every now and then, a notice comes up on the ipad which says "this accessory is not recognised." This notice has been deliberately placed there by Apple in order to persuade people to use only their products. Strictly speaking this sort of behaviour should be against the various competition laws but Apple seem to get away with it.

[Nicholas]

The reason I think it's strange is because Synthesia uses the exact same mechanism (Apple's CoreMIDI support) that all of those other apps do. Whatever devices they are seeing should be reported exactly the same by the OS to Synthesia.

Is there nothing at all listed in either (input or output) list in the Music Devices section of Synthesia's Settings screen besides the default "Synthesia Virtual Piano" and "iPad Synth powered by VoiceCrystal"?

[winters]

It looks as though I owe Synthesia an apology because I have just downloaded the free desktop version, and that is interacting correctly with my Korg keyboard, through a Focusrite saffire 6 usb midi interface. Then I tried my ipad Synthesia app through the cheapo generic usb to midi adaptor (ipad does not recognise my Focusrite because it uses drivers) once again to see if anything had changed since yesterday. Low and behold, Synthesia is now interacting with my keyboard in the normal way. I must have got the settings ass upwards, so, sorry Synthesia management, I stand corrected.

[KTinOhio]

Are you warning against any cable that looks like the one in the picture (I'd think any adapter cable would have to have two midi connectors and a USB) or a particular brand? If so, what brand? I have a Hosa Technology USM-422 version 2.1, which worked fine with my desktop but not my android. As far as I can tell there is no connection (input or p=output) between keyboard and android.

Unrelated question: What are those triangular symbols down the left side of the screen? Timing marks?

KT

[jimhenry]

Are you warning against any cable that looks like the one in the picture (I'd think any adapter cable would have to have two midi connectors and a USB) or a particular brand? If so, what brand?

A cable that looks like the one in the picture. Not just the connectors, which of course all cables of this type have, but the type of cable, the size shape and color of the electronics "lump" in the middle of the cable, etc. This is a generic cable that gets branded with many different names so I can't give you a particular brand. What's worse is that the electronics board is such that it can be built in at least two different ways, one better than the other. Even the bad form of the cable will work in some systems. But it doesn't meet the MIDI specs so there is no way to know if it will work for you. Or if it might stop working if you plug your keyboard into a different power outlet. If someone says they are having strange issues with the MIDI input I ask if their cable looks like this. If it does, my answer is that it isn't worth their time to try to figure it out. I don't recall anyone who wasn't able to solve the issues when they were using this cable by replacing it with a recognized brand name cable.

[Nicholas]

Unrelated question: What are those triangular symbols down the left side of the screen? Timing marks?

Those are notes (usually for the opposite hand) that are off the side of the screen. You can click and drag left/right in the falling note area to pan over and see the notes.

[KTinOhio]

Can you suggest a brand and/or model for a MIDI cable that will work well?