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FYI! Last read at 04:18 on 2024/11/24.

Keyboard fix

I said in the last post that the foamy stuff around the speakers was falling apart. Indeed it was, given that it was foam, it was as brittle as gold leaf; and in some places had already fallen apart.

This would not do.

Problem is, what to fix it with? My first inclination was to whack a piece of fabric in there, but I rejected all of those ideas on account of the risk of fabric muffling the sound.

I needed something black, very thin but not transparent, easy to cut up and use, and inexpensive.

After some thinking while I was at work, I hit upon an idea of what I needed. Tights.

I must say, it is nice to be able to pass through a checkout at a supermarket with super glue, a screwdriver, and a pair of tights and not have the checkout girl bat an eyelid or say "what the hell?".

I'm not a girl so I don't know the thickness of these, I just picked the thickest/cheapest pair on the display, and left it at that.

As it turns out, it was a perfectly reasonable choice. I decided to use my hot-melt-glue-gun because of the likelihood of things going badly wrong with superglue. So here I am with a square cut out to put into place:

Making a new speaker cover

Here is the finished object:

Making a new speaker cover

And finally, the end result:

Making a new speaker cover

 

Keyboard analysis

Given the age of the keyboard, and the fact that it is mostly digital and not analogue (so less useful for "circuit bending"), there is not a lot of information on the internet. I did find a scan of the user guide, which was extremely useful.

The sounds are generated by synthesis; so the timbre isn't as good as the Yamaha - however for its age it offers pretty good sounds. Some are better than others, obviously. Strings don't tend to sound so good, while the piano and variations such as the harpsichord are pretty decent, for a synthesiser.

Good in its day (1994), it offers 24 note polyphony, 223 different sounds (though how to get at some of them?), and 32 internal styles.

Keyboard control panel

The MIDI support is, strictly speaking, non-conformant. It would appear to offer around five channels which are fixed to certain functions (General MIDI (1991) specifies 16 melodic and flexible assignment). It would appear as if the E-16 is set up as such:

ChannelPurpose
1Accompaniment #2 (main part, such as piano etc)
3Lower (left of keyboard split)
4Upper (right of keyboard split)
5Accompaniment #1, Accompaniment #3 (?)
8Accompaniment bass
10Manual/accompaniment drums (dedicated channel)
16Note to arranger (control, event trigger, etc)
It would be a little bit inconvenient if the MIDI is too "eccentric" to play a four/five instrument composition, but it isn't the end of the world.
I can see myself writing some code for RISC OS to strip a MIDI file and direct the melody to my Yamaha and the bass to the Roland. The contrabass is a bit synthy and silly sounding until you crank up the volume, then it's like "whoa!". This is something the Roland does well - powerful output and capable bass.
However... That'll need to wait until I have picked up a USB-MIDI dongle.

Roland E-16 back

In terms of cost - assuming you can find one - the price is all over the place. Amazon.com is selling one for under $30 (and that includes postage) while here in France PriceMinister is listing one for €99 with nearly €25 on top postage. The next offer is €199 with a stand. No postage, you have to pick it up from a place near Nice (well, that explains the unrealistic price). Nothing on eBay except parts. Somebody is selling the main board for €22(+8P&P). Mine...cost a Happy Meal. <giggle>

Still, it isn't about cost, it is about usefulness. The true usefulness will be determined by the exact MIDI capabilities; however otherwise it is a pretty solid regular size keyboard that offers touch sensitivity and accepts a sustain pedal. The only downside is the lack of battery support meaning, at the moment, it needs to be tethered to a power supply.

 

Roland E-16 Mainboard

Following on from my cursory look in the previous entry, I have had a deeper look at the main board of the E-16. I have no service manual, so take this with discretion.

First, the main board:


[larger image, 2104×1286, 1.37MiB]

The two sockets upper left are MIDI. Below that, by the ribbon cable, is a buffer chip (IC13) - more specifically a Bipolar digital NPN transistor array (TD6250). It would appear that this is output to the LEDs. There is nowhere near enough wires for the LEDs present, so I would guess that there are some data lines and some address lines and the LEDs are either updated cyclically, or state-latched.
To the right of this, the 32KiB SRAM (IC15). It appears to be tracked into the synth chip. Purpose unknown.
The giant upside-down chip is the TC6116 tone generator / synthesis chip (IC17). It has been used in all sorts of places, such as PC sound cards.
To the upper right of the synth is an MB838000 (IC18). This would appear to be a 128KiB mask programmed ROM. Contents unknown.
The circuitry on the upper right appears to be audio filtering and such.

Back to the lower left, a custom gate array (IC9) for interfacing the keyboard and the front panel buttons.
The big red plug is a connection to the front panel. Again, many more keys than wires so it'll be 'plexed somehow. Underneath the ribbon cable are two similar cables connecting the instrument keyboard.
To the right of the lower ribbon cable is the MB84256 (IC8) which is another 32KiB SRAM. Purpose unknown; suspect CPU stack and such.
To the right of that, an HN62334 512KiB mask programmable ROM (IC11). Contents unknown; suspect "operating system" and data tables for the synthesis.
Finally, the square chip (IC12) which is a microprocessor. Part HD6435328 - it is a H8/532 processor. This is a composite chip that contains a custom Hitachi processor core, I/O handling, timers, ADC, serial ports, and such. It is sort of a precursor the the sorts of microcontrollers popularised by the PIC family. It is pretty flexible, with an instruction set that seems part RISC and part PDP/11.

 

Your comments:

Michelle Hellemons, 17th November 2013, 11:01
Hi, 
 
Firstly, a great blog. I love your speaker fix and the fact that you open the back to have a look.  
 
My daughter has a Roland E-16 which works perfectly except for two false notes. Have you any idea how to fix these? Thanks 
 
Michelle
Adrian Alexander, 3rd December 2013, 11:55
Hi. Great blog. Do you perhaps have a picture of the Roland E-09 motherboard? Or do you know the audio output IC (IC300)? Thank you.
Joel dC, 8th December 2013, 10:30
thanks for this blog...now i can see what's inside. 
i had my e-16 since 1996 and still working perfectly today 2013...all still in perfect tune... wow.. 
i have never dismantled mine and now i am planning to due to failed volume control..common in analogue potentiometer type that the carbon might have been used up already. strange that the only affected is the left channel. if you have the parts number i appreciate if you could email me. 
again thanks for this blog 
Rick, 8th December 2013, 10:56
Michelle - was answered to ask for clarification on what was meant by the two false notes. I don't understand how a microprocessor can detect the key press yet get the note wrong, so I asked for more information. No response. 
 
Adrian - sorry, no. I am still trying to find a schematic/details of my E-16, never mind other models! The information I have here was assembled by putting the ID numbers written on each chip in to Google and reading a lot of stuff. Does your IC300 have anything printed on it? 
 
Joel - as above, I have no schematic so no part number. It is quite common for only one channel to be affected because the two audio channels are tracked separately and one wears out before the other. Happened to me numerous times with cassette tape Walkmans (Walkmen?) through the '80s. ;-) Good luck on finding a suitable part.
gid, 9th June 2014, 01:56
I have upgraded my keyboard as the original is only 61 notes and the keys lose the touch sensitivity after a time and even go dead. 
So the k-b has been removed and the rest made into a kind of midi box- with speaker output. 
e-16 works well as acceptor of midi signal from a (better 88 note weighted dummy keyboard) but on the e-16 I can't alter the notes from midi in- to split the k-b or adjust the voice or synch with the drum- there is no jumper to force it to adjust midi in? 
Direct ribbon cable from the controller keyboard would work but its 20 pin micro match on the tatar k-b to 16 pin micro match cable on the roland.
Toni Nohant, 16th August 2014, 02:21
About the losing of touch sensivity seems pretty comon in those kb's and I solved with a cleaning/touching the keybord switch, below the key, so you have to take off the key to get to the switch.
John, 31st December 2014, 17:46
I have an E16 with few dead notes at regular intervals. Checked for broken tracks on the pc board (keys), followed ribbons to mainboard, just after ribbon connector(what are the 3 blue components).I suspect these are something to do with my problem. Could anyone on the forum assist me in this regard. John, Cape town, South Africa
John, 10th January 2015, 00:17
Dear Rick, the 3 blue components on the main board of E16 are Resistor Arrays directly linked to the gate array IC9.just under the IC9 there are 8 holes connected from the KB contact board to pins 8,9,10,11,13,14,15,16 give you 8 notes per zone, the left side from pin56 to 80 determine the zones on the contact board. I found no activity at pin 16 and that explains the dead notes on each eighth key. Can the IC be replaced and where can one purchase it? I followed each track on the pcb from the KB connectors to IC 9 and made a rough drawing of it. It's easy to see what pins to short to give certain notes. Will try and upload it as soon as I have it drawn neatly. Please also recommend IC's similar to this that can be used. Regards, John
, 28th January 2015, 19:33
Hello dear, I've bem looking for a one main board o this keyboard e16 if know how I can find one of this please tell me by my e-mail, thanks.
Revelation, 18th May 2015, 09:04
My Roland E-09 does not switch on at all what could be the problem
Rod Lloyd, 23rd May 2015, 04:50
Hi. Thank you for your page. I have a Roland E16 I am seeking to repair but am having difficulty removing the cover. I have removed the peripheral screws and the three inner one (not sure if that's needed. But I am unable to lift it off still I don't want to force anything and little around about this older model now. Most appreciative if you have any suggestions? 
Thank you.
Trev, 28th November 2015, 14:53
Same dilemma as Rod. 
Was going to import two contact strips from Syntaur USA (marginally below VAT threshold) but pointless if cannot remove cover. Can slide screwdriver around rim but it does seem something might snap.
Rick, 28th November 2015, 19:36
Hi Rod and Trev, Unfortunately my Roland is packed up in the attic at the moment (I use my Yamaha, better MIDI support) but nothing unusual comes to mind regarding dismantling.
eliezer, 19th April 2016, 20:07
herma buenos dias se ra que tiene la posibilidad de indicarme el modelo y numero de salida de audio de roland e16 lo q pasa es q seme daņo y lo mande a reparar y me estafaron le sacaron las salidas y no me las dieron
Sies, 29th April 2016, 17:05
Thanks for your tutorial! I changed it exactly the same way now :-)
Lucky, 25th July 2018, 14:09
how do you Replace the Sound IC on a roland e09
Lin, 4th January 2019, 12:27
Hello Rick  
If you are still responding to messages  
I have just bought an old Roland e16 and the foam is torn on one side and wondered how you got into that part to fix it with the tights? 
Did you have to open the whole Synthesizer?  
Thanks if you can respond
Bryan Keane, 16th July 2020, 14:59
Can you please help find a schematic diagram for my Roland E-16 Power/Amplifier Board  
I have spent some time on the web trying to get one with no success. 
The WRONG power supply was plugged in and poof. 
+/- wrong way around! 
Any help at all would appreciated 
Thank you
Bryan Keane, 16th July 2020, 15:02
Can you please help find a schematic diagram for my Roland E-16 Power/Amplifier Board  
I have spent some time on the web trying to get one with no success. 
The WRONG power supply was plugged in and poof. 
+/- wrong way around! 
Any help at all would appreciated 
Thank you

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