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Updates: Many topics are permanent, so may be updated to any material, for add or correct info.
Get more info: Since the beginning this site tryes to be a compilation center of the best sources for the JD800. Not a copy.
So please, visit the sites at the Links section for lots of much more very good information.

quinta-feira, 14 de novembro de 2013

60 very nice users presets

Great user presets done from scratch using only the internal waveforms and the beast sound generator and effects of the JD800.

User:  Default Corporation - Piemonte, Italy

Volume up and enjoy!





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sexta-feira, 16 de agosto de 2013

White Keys Again



This is from "The Retr0bright Project".

By Merlin, of AmiBay, English Amiga Board and Vintage Computer Forums (among others)

How to deal with the “not-so-mellow yellow” of old computers and consoles

“The problem was finally cracked in late July 2008 with a mixture of hydrogen peroxide, a small amount of an “Oxy” laundry booster as a catalyst and a UV lamp; we believed that this could do the job in hours instead of days. Proof of this concept was demonstrated on EAB by Tonyyeb from Hull, UK, Chiark from Leeds, UK and myself. The original test I did as proof of concept took two hours, as opposed to up to the five days it took for the original tests at CBM and a1k.org. We were on to something!!

See the complete article at: retr0bright.wikispaces.com



Portuguese text: 

Coloque as teclas em água oxigenada + bicarbonato de sódio e deixe algumas horas no sol. De preferência cubra o recipiente com um plástico.


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sexta-feira, 8 de março de 2013

One Fix for the Red Glue Problem

JD800 by Marcos Carrera from Taiwan.


This was posted by Shupac800 at the JD-800 Tech Group:



My Fix for the Red Glue Problem
Posted By: shupac800  Sat Aug 4, 2012 8:10 pm 
I posted this tutorial to Gearslutz.com last year and thought it might be
helpful to republish it here.

* * *

There are two kinds of JD-800 owners: those who have already experienced the
red glue of death, and those who are going to...

As we all know, the red glue that holds the key weights to the keys did not prove to be stable over a period of decades. When it gets old, and especially if the synth is kept someplace warm, the red glue softens and seeps out, making a God-awful mess.

The best way to fix this problem is to remove all the red glue, under the mildest conditions possible (NOT boiling water, as some have tried), and re-glue the weights into the keys. The keybed comes out better than new. Here's my technique.

Sodium hydroxide (NaOH, lye) solution works great to dissolve the red glue without harming the plastic. It is caustic, so WEAR SAFETY GOGGLES. Even dilute NaOH can permanently damage your eyes, and it's very likely your lye solution will be splashing about. If you get any of the solution on yourself, wash it off promptly with a lot of water.

The sodium hydroxide I like to use is granular NaOH, which I've bought on eBay. If you can get Red Devil lye or some other pelletized NaOH at your hardware store, that will work too, but the granular NaOH dissolves faster.

In a plastic bucket, mix 80 grams NaOH with 2 liters of water until all the NaOH is dissolved. (The bucket will get warm.) For you chemistry types, this recipe makes a 1-molar (1 mole/L) solution of sodium hydroxide.

Immerse the keys in the lye solution. You only need to soak the part with the glue on it, so don't worry if keys aren't completely bathed in the solution.

Leave the keys soaking in the solution for 18-24 hours. After this time, no traces of the red glue should remain, and the weights will simply fall out of the keys into the bucket.

Carefully pour the NaOH solution down the drain. Don't let the weights get poured down the drain too.

Rinse everything with a lot of water. Dry the weights as best you can. It's normal for a bit of rust-colored oxidation to form on them; don't worry about it.

At this point I soak the keys for another 24 hours in a bucket of soapy water. This bath helps eliminate the fishy odor left on the plastic by the reaction of the lye solution with the red glue.

When everything is dry and clean, re-glue the weights into the keys. I have had great results using a popsicle stick to apply a dab of 5-minute epoxy to each key. Make sure the weights are properly centered.

To remove any red goop that has seeped onto your chassis, I have found the best method is to blast the goo with freeze spray (available from Radio Shack or Fry's). Then, while the stuff is frozen hard and brittle, chip it off with a single-edged razor blade.

And that's it. Have fun.




Another fix by Daniel Forro at the same forum: 
(observe his comments about how reglue the key's weights)



My problems with red glue started few years ago after my moving from middle Europe to Japan - I think also because of high temperatures in the summer.

It's necessary to disassemble the instrument and keyboard, and leave the keys soaked in solution with NaOH (natrium hydroxide). I used a liquid for
cleaning sanitary pipes with 2% of NaOH, it's enough, but it was necessary to leave keys in it for about 2 or three days. I have used transparent plastic
cover from 50 pieces CD or DVD box, lot of keys can be inside in the same time soaked (and after finishing the job and washing box in water it can be
again used). Red glue is dissolved with it perfectly, dissappears, and metal weights still keep glued (mostly, just few fell out).

Then I cleaned the keys with water, and with isopropylalcohol from the rest of dissolved glue film and all dirtiness, and put standard universal common
liquid "white glue" (which changes color to transparent after drying, and is soluble and washable with water - I'm sure it can be purchased everywhere in the
world under different names) to fill and cover all holes around the weight, and weight itself - to avoid any possible future leakage of red glue which is
still under the weight. After drying this glue I had apply more of it on some spots where some air bubble made again holes. In the end I got perfect plastic cover
of metal weight. If I remember well, for black keys it was necessary to use more glue.

There's no problem since the repair.



.'.


Here is another topic about the Red Glue problem: Sorting Out Flats JD800 Sticky Key - Red Glue


sexta-feira, 31 de agosto de 2012

Playing the Gandalf

I don´t know if there is another Gandalf - The Roland JD-800 Custom White Synth.
It is really a nice white custom mod.
So, just see this:



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segunda-feira, 6 de agosto de 2012

Memory Card Battery Replacement / cartridge

It is important to remember you cards / cartridge have an internal battery.

This is the former process for replacement.


All rights: @Roland Co.


Download the original PDF file from Roland US:  Roland_Memory_Card_Battery_Replacement.pdf





Memory Card Battery Replacement Instructions

The Roland M-512, M-256 and M-128 memory cards each have an internal battery.

If you need to replace the internal battery, please use the following images as a guide.


Be sure to use the specified battery (CR-2016) - This is a very popular type usually easy to find.




1)  Locate the battery tray and use your thumbnail or the blade of a small flat-head screwdriver to gently loosen the battery tray.



 2) Gently pull the battery tray completely out of the memory card.


 3) Make a note of which side of the battery is facing up so you can position the new battery correctly.


4) Take care not to touch the new battery with your bare fingers as this can shorten battery life.
 




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quinta-feira, 24 de maio de 2012

Rick Wakeman with a JD-800 at stage


I´m looking to find some pictures/videos of Master Rick with his JD-800.

Here, Rick Wakeman in 2009, playing live in Lugano.

The Roland JD-800 is in the center on top of image. The Moog is just at left.

Image from the DVD 'CLASSICAL WAKEMAN'
Vol. 1- Live in Lugano

And here in another moment:

Master Rick Wakeman is an English keyboard player, composer, and songwriter
best known as the keyboardist for progressive rock group Yes.
Foto: StarCards


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terça-feira, 8 de maio de 2012

JD-800 Aftertouch Modification


Use the full range of aftertouch without straining your fingers.


DISCLAIMER:
This is a Mod to the JD-800 circuit. Do it at your own risk.



Photo:
All JD-800 users knows we need to put a lot of pressure to use the aftertouch.

As someone sayd: one needs to stand on the keyboard to get an effect.



I took here the work of two great guys from the JD-800 Tech group. As I know, they had many messages about this work and here is the result with comments from both.

Preben Friis, synth lover an expert in electronics who explain how to do a simple mod to make the aftertouch become better, really light to play.

, a guy who have great merits and a lovely work and story.

From now, I merge material from both and something more, including one or two words of mine.




The Idea:

Preben:

In basic, just change how the circuit "feel" the input value.
A 270 kOhm resistor across R27 will make it possible to use full range of aftertouch without straining your fingers.

R27 position.
Photo:



Please read all the comments before doing anything you will repent! (LOL)




Researching:
I poked around with a multimeter on the aftertouch circuit today. The pressure
ribbon starts out at 150 kOhm and by full pressure it is around 1 kOhm...

Shunting the ribbon will make it possible to move the threshold to make it start

earlier but will not make it more sensitive.
Preben


CAUTION:

This is a modification you can do inside the JD if you are comfortable with a soldering iron that makes the aftertouch much more responsive.


This mod might require to unsolder a SMD resistor ... not something for people with ten thumbs.
For sure you can ask an electronics technician to perform this modification.


About opening the JD-800:

Removing all screws may do your internal components fall.
You must remove only the screws AROUND the bottom and two screws in the center line, they are at 1/4 from side, and may be you can see a few bigger hole where thy fit to.
Sometimes the bottom have some "dust" acting like glue to.
Photo:




How to remove the panel.
JD-800 Manual. (click to enlarge)
Source: Roland Co.



The Solution:

Preben:

Thanks to Gwydion Elderwyn I received exactly what I needed to calculate and test a better modification of the aftertouch circuit in the JD-800.
The short version: 
Change resistor R27 to 120 kOhm instead of 220 kOhm. Done.
The long version:
Since SMD components are very difficult to remove, and I did not have any SMD components at hand, I chose to solder a 270 kOhm resistor parallel with R27. 
R27 is located on the mainboard in the left corner right by the ribbon cable to the keyboard.
The picture shows my "huge" resistor piggyback on R27. It is not very pretty, but it works! 

Image by: Preben Friis

 
Actually the picture shows a 100k resistor, which was the first one I tried, but that made the aftertouch sensitivity too light. I could easily press the aftertouch from 0 to 127 with my pinkie finger. The 270k resistor is in my opinion the best value. If I use my pinkie with this value it allmost hurts to press it to max. Feel free to experiment - Reasonable values are in the range from 100k to about 1M
Find a soldering iron with a very thin tip and add a little solder to the two pads on R27 first. Then cut and bend the legs of the new resistor to fit across it and add a little solder blob to the legs of it. Hold the new resistor in position with a set of pliers and touch the iron to the legs of the resistor. This should melt both solder blobs to one and the connection is made. Repeat for the other side.
The smaller the better: 
A 1/8W resistor would be preferred over a 1/4W. 
Smaller resistors have thinner legs and that makes them easier to solder to the SMD resistor.
(Acutally I'm currently using a 1/2W resistor and it is BIG!).


The tolerance does not matter much. You can use 220k or 180k if you really want to use the full aftertouch range when playing monofonic lines.
 
An alternate idea:
Marc (also suggest using a trimmer instead of a fixed resistor:
What I'd like to do instead on this mod is replace the resistor by a lower value, cut the trace next to it and connect a 500Kohm trimmer pot with modding wire (26-28Awg) and have it adjustable. 
I imagine not every aftertouch ribbon has exactly the same value, so this would make it tweekable. Nice thing is if the value of the ribbon changes in time, all you have to do it open it up and adjust it a little. The fixed resistor is there as safeguard so the value doesnt go below a safe value and draws too much current.
Also, I would not connect a pot in parallel with the current value. The response of the pot would not be linear at all, and hard to adjust. 

Another mod using the same idea:

See that was placed a wire connecting the potentiometer (at left) to position R27 in the circuit board.
Foto: Yuri Alfons Peeters Charlotte

Remember to power off before you solder anything... 
If you connect the resistor properly without shorting anything there is no risk involved in this modification. The current in the pressure ribbon will be double from around 40 uA to 80 uA, but those currents are still very far from anything that can destroy any components.

I can tell you, that a well adjusted aftertouch is almost like getting a new synth. Many of the factory sounds is way more fun to play around with, when you can change the sound by a light pressure. 
For example, try for instance patch I-22, Classic Sweeper .. 
Thanks again Gwydion Elderwyn, I couldn't have done this without your help :-)
Have fun.

Preben Friis






The Circuit and the mods
























As we say here in Georgia, WEEEEEE HAAAAAA!

Thanks Preben!  This mod was easy and it works great!  I used the 270k and find the aftertouch to now be similar to my K2000.

Most excellent.  Kinda makes you wonder why Roland didn’t get it right in the first place.

Jim Combs
www.touchxtone.com


 

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