Archives for : jd800

Roland JD-800 keys not working? Let’s fix it!

Suddenly several keys stopped working. It was too suspicious, especially since they were 8 semitones apart. I did install the new rubber contacts, but the problem was still there, as I’ve expected. Turns out the problem is the ribbon cable connection. It eventually wears off. But that’s just half of the problem.

The main problem: Those plastic “screws” holding two ribbons together do not provide enough pressure. But even if they did, that plastic plate which is supposed to hold one ribbon on top of the other – it will bend and not make a solid connection between two ribbons and hence the keys will not work.

Solution: rebuild the connections. Replace plastic “screws” with metal ones. Place a metal plate on top of that plastic plate and tighten with those real screws and nuts!

I forgot to say, contacts wear off even faster if someone tries to clean them with alcohol. The contacts are almost gone. Seems like no repair can be possible as you can’t solder anything to the flex PCB. But there is a solution in a form of a contact repair kit. It is a silver based solution for flex type PCBs. Check your local Mouser / RS/ Farnell store for details. Anyway here is the state of the ribbon contacts:

First thing to do is we have to create a mask. Distance between connectors is around 1mm, so you will cut 1mm wide strips. I helped myself by printing the raster so the cutting was much easier:

The mask is ready:

First couple of contacts are ready. Please ignore the mask on the top. You won’t need it. It was my attempt of soldering onto the flex PCB. So I had to rebuild two extra contacts:

Adding more strips:


Before applying the solution, clean the contacts first. I would recommend q-tips and some non alcohol based liquid, something as simple as window cleaning solution and distilled water. DO NOT USE ALCOHOL, it will melt the contacts entirely and you won’t have anything left to restore. There is no replacement part from Roland. Once done you can apply the sliver based solution. I used three coatings total:

24 hours later. Gently peeling off the strips:

And now we have entirely restored ribbon contacts:

Cutting the metal plate to the same dimensions as the plastic plate which was used to hold the ribbons together. Do not throw away that plastic! You will need it. You can throw away those two fake plastic screws though:

Drilling two holes on exact location they are present on the stock plastic plate:

Now place that original plastic and the new metal plate on top. The reason for this is – the original plastic will bend, while those plastic screws do not provide enough pressure. As a result the ribbon will not make a solid connection and the keys will not work:

Tighten those screws properly. And now finally you have a solid connection! Make sure to align two ribbons precisely before inserting the metal plate as it is obviously opaque, so you can’t see thru it to align. Use some masking tape temporarily if needed:

Now you have real screws and a real metal plate to hold two ribbon cables together:

No more bad key contacts:

Roland JD emulation on Super JV and XV synthesizers


Starting with model JV-1080, some waveforms from the JD-800 were transferred into JV-1080. Which meant back then that some of the patches could technically be transferred from JD into Super JV synthesizers. Unfortunately what Super JV series missed was the effects section from the JD, and thus most of the patches were a total miss. (Notice: Well this is just half of the truth, the other half is a different gain structure, filter dynamic range and 44kHz waveforms vs 32 kHz ROM, but let’s pretend for a moment we have no idea about this. If you’re curious about details, go to our Ultimate Roland JD JV FAQ article). Anyway, the process of JD “migration” continued with XV series, to the point that many of the 108 JD waveforms seem to be available in the XV synths – seems like 7 are missing – but they could be different name. This part is unfortunately unconfirmed and requires someone doing more in depth waveform tests.

Of course what would be a JD without it’s special multi effect processor. That’s why Roland implemented JD’s “Effect processor A” into XV. In other words, you got a JD synth hidden inside your XV synth, and you can finally start converting favorite JD patches. There are some differences in the filter, but more on that later. I should just state that the 44.1k referenced samples points to models XV-5080 and XV-5050. I can not guarantee that model 3080 contains 44.1k playback engine at all, neither the samples in that format – it has been reported the machine is 32k. I can however guarantee than in 5080/5050 waveforms from the JD-800 are in original 44.1k format.


Table below shows us internal memory content (waveforms) of the JD-800. Starting with ‘’001 Syn Saw 1′’, ending with ‘’108 Wind Chime’’. Position of these same waves inside XV synthesizer are marked with orange color. For example if you want to load Syn Pulse 4 that on JD is waveform number 008, on XV you will find it on number 557.


JD-800 multi effect group A
With the XV synthesizer, Roland also brought us back the famous JD-800 multi effect from its section A block (note: the JD has two effect sections). On XV series it is available as MFX number “75: JD MULTI”. Just like on the JD-800, it allows distortion, phaser, spectrum and enhancer effects to be connected in series in any desired order. It features exactly the same settings as available on JD-800. Here is a brief explanation for each one of them.

1. Distortion
The first effect in the chain is obvious – a standard distortion. This effect is useful in situations when you wish to add some drive to solos or do some nasty clipping effects depending on the sound design application. There are seven types of distortion available:

  1. MELLOW DRIVE: A soft, mellow distortion; somewhat darksounding.
  2. OVERDRIVE: The classic sound of an overdriven tube amp.
  3. CRY DRIVE: Distortion with a high-frequency boost.
  4. MELLOW DIST: Sounds like the distortion you’d get from a really big amp.
  5. LIGHT DIST: A distortion with an intense, brilliant feel.
  6. FAT DIST: Boosted lows and highs gives this one a thick, fat sound.
  7. FUZZ DIST: Like FAT DIST, but with even more distortion.

2. Phaser
In typical phaser, modulation effect is created by mixing original sound with a phase shifted one. Result is a swirling effect and is best suited for backing sounds such as strings or electric pianos. Phaser will be most effective on sounds rich with harmonics, such as saw or pulse waves. Therefore it would be better to insert the phaser after the distortion or spectrum. For the best results, you should use center frequency at around 1 kHz.

3. Spectrum
Spectrum is an effect that modifies sound by boosting or cutting specified frequency areas, resulting in different tone colors. This effect might look similar to an equalizer. However, the frequency of each band has been set at the optimal location for adding a distinctive character to the sound. Rather than correcting the sound, spectrum allows you to aggressively modify the tonal character.

Spectrum will be best heard on spectral rich sounds such as white noise. There, the change will be most evident. For most expressive result use narrow bandwidth (set it to 5) and try setting all bands to max gain (positive or negative). When using wide bandwidth settings (set to 1) sound becomes less distinctive, and it starts to sound like an ordinary EQ.

4. Enhancer
Enhancer is a sort of aural exciter type of effect. Can be effective for sharpening up the vocal types of patches, flutes, guitars, etc. It will really help the instrument (patch) stand out in the mix. Its function is to generate new overtones out of the fundamental ones. With sensitivity you can set the depth of enhancer effect. While with the mix parameter you are specifying the mixture of original sound and the newly created sound overtones.

Effects setup on XV
Image below shows us the real JD-800 effect processor routing. As you can see, effects group A is connected in both series and parallel to group B. Same thing can be done in XV. The only difference is that on XV there is no effects group B, but instead there is separate chorus and reverb/delay. Since they can be configured in series or parallel, you can think of them as “group B” with only difference that you can have either delay or reverb, but not both like on the JD.


Image below shows us typical JD-800 effects setup emulated on XV. Chorus and reverb simulate JD’s “effect group B” while MFX: 75 JD Mlt provides “group A”. In this example, group A is connected in series to group B. Inside group B we connected chorus and reverb in parallel (M+R), so that we get chorused signal out followed by reverb/delay (in this example i used Reverb 1, type: Delay).


It is possible to have delay and reverb at the same time, but you will lose chorus. If this setup is required, just set chorus to type 2: delay (200-1000ms). Now you will have both delay and reverb. Please note this emulation will sound nothing like JD Effects Block B since they contain very different algorithms while some cult ones like Flying reverbs are missing completely.

Conversion table
Before starting to build or convert you first JD patches, keep in mind that JD and XV have different filter numerating system. For example, max resonance on JD is 100 while on XV is 127. Same is with the cutoff. And exactly the same thing applies for other parameters that on JD go in range from 0-99, while on XV and Super JV they go from 0-127. For better conversion of your JD patches you will need this JD/XV conversion table.


Roland Super JV?
Ok why giving hope to Roland Super JV users by placing it in the same title? Let’s say it is for those who are constantly sending me messages “how do i get this JD pad converted into my Super JV”. Well, to be frank, you can’t! You can try it. But you will never get there. Ok? These two machines have different gain structure and dynamic range which makes JD sound a little bit “harder”. For example you can not make soft sounding bass line on a JD, it will always have this hard character to it (not soft in a way you can make it on Super JV). The reason is higher gain and most likely smaller dynamic range of the JD filter section. But on the other hand you will never achieve those legendary high frequency shimmering pads on a Super JV, simply because i can’t go that high, neither it’s filter, neither its waveforms (which are 32kHz, compared to 44k on JD). And as already mentioned these two devices have different numeration. So if you still INSIST, here i am providing the above table for those of you who want to convert their patches. And for the second time, even if you convert all the parameters correctly, you won’t achieve JD’s sound on a Super JV machine, just like JD will never achieve the sound of a Super JV (which is darker, but also a much softer sounding – hint: analog style bass patches on Super JV are simply stunning). Ideally is to have both machines. So, there you go…