Kawai K1 & Roland PMA-5 MIDI jacks powered or not?

Discussions about anything analog, digital, MIDI, synth technology, techniques, theories and more.

Kawai K1 & Roland PMA-5 MIDI jacks powered or not?

Postby mmryspace » Tue Jan 23, 2018 6:38 pm

Hi folks,

My first post here regarding some newly acquired gear. I am trying to confirm whether or not the Kawai K1 and the Roland PMA-5 have MIDI jacks that are powered? For example, if I were to use the MIDI Solutions Quadra Thru BoxMIDI Solutions Quadra Thru Box with these two pieces of hardware, would either of them supply power needed to use the Quadra Thru or other attached devices that need power from the sending device's MIDI Bus/ Jacks? Any help is greatly appreciated. Thanks!
mmryspace
Newbie
Newbie
 
Posts: 3
Joined: Tue Jan 23, 2018 6:20 pm

Re: Kawai K1 & Roland PMA-5 MIDI jacks powered or not?

Postby ItsMeOnly » Tue Jan 23, 2018 11:05 pm

You are confusing things: this is basically a passive box using MIDI signals - usually between 3.3 and 5 volt (about 5mA). Unlike newer technologies, MIDI was not designed to provide power, as devices it was meant connect were already powered. In fact, most devices provide galvanic isolation of MIDI connectors (by optoelectric means - a diode with a photodiode - for example) for protection.

And to answer your question - if that box you got has bigger tolerance of current/voltage, it will work. <Otherwise invest in something like this, this or, if you're low on money, this
User avatar
ItsMeOnly
Active Member
Active Member
 
Posts: 301
Joined: Thu Dec 01, 2005 9:01 pm
Location: Warszawa, Poland
Gear: Wavestation, K3m, TG77, MOXF6, D-550, S2000, DeepMind 12;
Broken: DX100, 01R/W, U-220

Re: Kawai K1 & Roland PMA-5 MIDI jacks powered or not?

Postby mmryspace » Wed Jan 24, 2018 2:58 pm

ItsMeOnly wrote:You are confusing things: this is basically a passive box using MIDI signals - usually between 3.3 and 5 volt (about 5mA). Unlike newer technologies, MIDI was not designed to provide power, as devices it was meant connect were already powered. In fact, most devices provide galvanic isolation of MIDI connectors (by optoelectric means - a diode with a photodiode - for example) for protection.

And to answer your question - if that box you got has bigger tolerance of current/voltage, it will work. <Otherwise invest in something like this, this or, if you're low on money, this


Thank you for providing that information - very helpful.

I am not as concerned about the thru boxes as I am the sending MIDI devices themselves. Perhaps using that example was confusing - my apologies.

Since I posted, here is what I learned:
From Kawai Product Support:
"The original MIDI spec 1.0 specified a 5v power and the K1 as with most 80’s era synths supports that spec and it looks on the schematic like the K1 does supply that 5v power."

Also from the FAQ on MIDI solutions website:
http://www.midisolutions.com/faqs.htm has a list of devices that will NOT power the passive thru box but the K1 and PMA-5 are not listed there. I am sharing because it points to my initial question about the K1 and PMA-5 MIDI jacks. Powered or Not?

It also mentions (in much more detail, this is just a portion):
"If a device won't provide power to an original MIDI Solutions product because it is using the new 3.3V MIDI specification then no simple modification can be made to resolve the problem, inserting a Power Adapter or switching to a MIDI Solutions MultiVoltage product is the only solution. The device's MIDI output voltage can be measured between the center pin (ground) and the pin next to it in the counterclockwise direction.

In other cases the reason a device does not provide power is because pin 2 (the center pin) of the MIDI output has not been connected to ground as indicated in the MIDI specification."


I could try to measure the PMA-5 for voltage I suppose and I have also reached out to Roland for support as well...
mmryspace
Newbie
Newbie
 
Posts: 3
Joined: Tue Jan 23, 2018 6:20 pm


Return to General Synthesizers

Who is online

Users browsing this forum: No registered users and 18 guests