Roland JX-8P Upgrade mit Vecoven PWM & Retroaktiv MPG-8

If you are into that special 80s Roland analog sound like I am, this video will show you why you really don't have to ruin yourself for a Juno 60 or even a Jupiter-8!

Because there's also the JX-8P: A real underdog that the common synth snob will gladly ignore with a grimace to prove his ultimate sublimity over the mob!

Why you'd better not believe these vintage better-guessers and also why for me the JX-8P is the vintage Roland Poly with the best price-fun ratio? I’ll tell you! Stay tuned!

And because you've landed here at Wine&Synths, the synth channel where practical experience counts most, I'll tell you the following on top of it all: namely, how you can raise this, extremely iconic vintage synthesizer to the technical level of the 21st century! After a short sound intro, we'll go straight on!

The JX-8P and its time.

Hey, friends of sophisticated synthesized sound! Good to see you again! Even the JX-3P, the in many details clearly weaker predecessor model, is meanwhile often declared to be the better choice over the 8P, for reasons I don't really understand. And this makes even a bit more expensive. A very good video about the 3P, another controller from Retroaktiv and the Kiwi modification was recently posted by my colleague Starsky! Cool entertaining video!

Starsky Carr and the Roland JX-3P with the Retraktiv PG2K Controller.

And just like the 3P, the JX-8P, fortunately for us, just has to deal with a simple misperception problem:

Because, if you ask the interested synth amateur, he is guaranteed to answer that this can only be a digital synth. Which is already the biggest error. And what's behind it is actually a pretty clever marketing move by Roland to go with the tooth of the time! And that leads us directly to the first fascinating point that unites the Rolands of this era:

The design concept and its historical context:

We remember: 1983: Yamaha DX-7, away with the faders and pots and the few remaining buttons disappeared under foiled surfaces.
This was not a big deal from the point of view of the time, because the average keyboard player was more interested in whether the pianosound really sounded like a piano, and whether the bellsounds belled.

The combination of this user mindset and the new, now cheaper technology, paved the way for devices that could now be offered at much lower prices, thanks to the reduced number of components. Alpha dials and displays with menus now found their way into studios. And not only Roland followed this trend: Korg (Poly 61/DW8000), Akai (AX73) Sequential (Prophet VS), Oberheim (Matrix6), even Moog 8Source) did not stop here!

My first Juno-60 was given to me by a friend who was a "Neue Deutsche Welle" Keyboardist, who had just bought a brandnew Roland JV-80 Rompler with over 1000 fantastic sounds! “Here you can have the old piece of junk! The pianos and the organs sound far better in the new one!“ R. I. P.!

I swear! This must have been around 1991… In contrast to the other manufacturers, who seemed to rely completely on this keyboard mainstream and made the programming of their devices more and more invisible, Roland had not lost sight of the professional sound wizards!

Pseudo-Digital

And so the, at that time still highly innovative, Team Kakehashi came up with a brilliant idea: “Let's just, as long as we don't have anything "really" digital, put our old analog synthesis into a new box with a modern washable "digital" surface and loads of patch memory with great piano and String presets!” “Sounds just as awesome as the old Jupiter and only costs a third to make! And of course we make a cool entry level model of the Junos as well. Do you already know these new Alpha-Dials? It's going to be a big seller!"

“And for those incorrigible DIY programmers who don't like presets, we'll simply release the familiar analog user interface as an additional programmer! It's ingenious, isn't it?
Kampai Guys!"

Roland only goes digital in 1985 with the D-50!

Then in 87 finally the first real digital synthesizer from Roland, the D50, was released, which was based on Rom samples and had even more presets! And even for this one, as well as for its small offshoot D-10, there were also dedicated programmers.

The highlight of this concept was probably the JD-800, which was more of a programmer with an inbuilt synthesizer and could even be used as a programmer for the JD-990 19" version. With the JP-8000 Roland finally brought the analog user interface back onto a device.

The strongest points on the JX-8P-Series:

But back to the early models of the JX-XP series whose strongest point is the next one:

1. Analogue Sound
Much has been written and said about the sound of the JX-8P. And of course there are already different sound demos here on YouTube!

Therefore, in addition to our handmade synth demos according to the #onesynthchallenge principle, which have been playing in the foreground and background all the time, I'll give you a short overview of the structure of the JX-8P and what makes it different from its Roland relatives:

The Roland JX-8P is a 6-voice analog polyphonic synthesizer with 2 oscillators per voice. Like the Junos and the JX-3P, it uses the digitally clocked DCOs instead of the purely analog VCOs of the Jupiter series, which was already obsolete at that time. The result is simply a more accurate analog wave. And at that time they did this for 2 reasons:

2. Tuning stability The main advantage of DCOs over VCOs. Their frequency is clocked digitally, instead of being clocked by an analog circuit. Compare it to a quartz driven watch with an analog display as opposed to a watch with a mechanical spring based movement. Both can have the same analog display. For a long time, this lack of precision was the main problem for most manufacturers when it came to build a polyphonic analog synthesizer with reliable tuning stability. With the DCOs, polyphonic synthesizers became affordable for the masses for the first time. Korg was already on this path in 1982 with the Poly 61, while Oberheim was only ready to use DCOs in the Matrix6 in 1986.

B. It simply looked so much better in the catalog, since you could now also throw in the buzzword "digital"! I love this Japanese efficiency! Have I mentioned that already?

Concept and structure of the Roland JX-8P

Unlike the Juno models, the JX series has two DCOs per voice, which again makes it seem more like a successor to the Jupiter series in Roland's portfolio context from that time. Also, the rest of the synthesizer is solid Japanese home cooking that doesn't raise any big questions. The DCOs can each be modulated by a pitch envelope and an LFO. Unfortunately, the JX only has one of these. But in addition, the DCOs allow to be synced. There are two sync stages for this, as well as cross modulation. With this, metallic sounds reminiscent of FM synthesis already went quite well, as these wonderful bell presets prove: (Sopndbeispiele). Unfortunately, just like the JX3, the JX8 lacks pulse width modulation. There are some workarounds to achieve something similar to PWM.

However, this is not necessarily the same. In comparison to the Jupiters, this would be the biggest point of criticism, which you hear again and again. Apart from the DCOs and the reportedly slow envelopes.

Both oscillator signals then enter the mixer. The mixer also features the JX-8P-typical dynamic envelope modulation, which we already found in the oscillator section and which can also be found in the filter section and the VCA. This allows very sensitive control of the selectable envelopes via velocity.

Filter

The filter section is based on the classic Roland IR3109 design, which was already used in the Jupiter and Juno models. The JX-8P uses the IR-3R05 filter IC, which has the advantage over the 80017A used in the Juno-106 that it does not disintegrate. Unfortunately, Roland limited itself to the configuration as 24dB low pass with a preceding 3-stage high pass. Theoretically, this device would have offered significantly more filter configurations.
Therefore it just sounds extremely good. Also the resonance always stays in moderate sweetspot areas and never shocks with uncontrolled self-oscillation. But it can also squeak and scratch: (Example sounds! Filter!)

Envelopes

Oscillators and filters are modulated by their respective ADSR envelopes. The envelopes of the JX-8P have the reputation of being a bit slow. Well, they are not the crispest, but are the sounds in our demos so far lacking in attack and transients? (Sample sounds - Possibly sample waveform from the envelopes).

Chorus Effect

Finally, the cream on the sound cake is the chorus, which is offered in good old Juno style with two different speeds. Unfortunately, you can't select both modes at the same time here like with the Juno 60, which resulted in a third effect. But considering that the chorus was actually just a cheat solution to fatten up the Juno 60's single DCO a bit, the chorus in the JX-8P is a welcome option to really over-fatten sounds. By the way, the noise of the chorus is always quietly audible and visible even in the JX-8P... (picture mixer channel).

Hands on:

Overall, the synth feels quite massive and weighs just an acceptable 11.5 kilos. Without flightcase...

The first surprising thing is the keyboard, which is very easy to play and also
has aftertouch in addition to velocity. The 3P did not have that yet! The keyboard of my unit is a bit worn out and needs to be refurbished soon. You need gentle force to trigger the higher velocity values. And the aftertouch is rather an afterpress. This is unfortunately the case with many JXes, just like with many other synthesizers of this age. That's why I prefer to play it via an external keyboard.

Other than that, the JX-8P is a vintage device that gives fairly little trouble. As with all vintage units, sooner or later elkos on the power supply can break and the faders on the control panel on the left, especially EDIT tend to give up sometimes and are probably a bit harder to find by now.

The buttons under the plastic surface foil are also relatively easy to replace if needed. I had this 8P overhauled and modded by Kai at X-Tended in Berlin. And those were essentially the weak points, which he listed to me on that occasion and from which this specimen also partly suffered.

Modding

Which brings us to modding:

Vecoven-Mods:

Fred Vecoven from Belgium is an electronics engineer by passion and luckily also an uncompromising synthesizer freak with extraordinary good taste! Many years ago, he thought that his Super JX10 would sound much better with PWM after all. This culminated in him rewriting the entire firmware code. For the PWM he then developed an additional hardware board that replaces some old chips of the soundboard.
And since some time there is the mod also for the JX-8P. This consists of 2 components:

1. The firmware upgrade comes on a small flash module that is inserted to replace the original EPROM. This can be done by non-experts, as soldering is normally not required. The new OS does not yet affect the sound, but finally lifts the Roland JX-8P into the 21st century on the MIDI side. Here is an overview of the most important features:

Parameter changes on the device or on the PG-800 are now transmitted either as SysEx or MIDI-CC. And of course also received, which makes remote control of the JX via a DAW or external controller now much easier and much smoother. For this, Vecoven has given the JX an additional MIDI implementation, which offers a variety of filter and dump settings.
32 additional internal sound banks with 32 sounds each. So there are now a total of 1024 sound memory locations available, which by the way are already filled with hundreds of interesting sounds!
Patch parameters like (key assign mode, aftertouch mode, portamento time, etc..) are now stored with the patch.
An arpeggiator and a chord memory function are now also available and are accessed as follows.

(Arpeggiator und Chords Soundbeispiele)

In any case, this is quite a benefit if you intend to use your JX-8P seriously in a modern MIDI setup.

2. The PWM kit is the second part of the MOD:
For this, however, 6 ICs have to be desoldered and new ones have to be soldered in. And there it was clear for me that this will be done by Kai from X-Tended here in Berlin, who then charged me almost 4 hours of work for it. And if you look at the perfectly illustrated installation instructions, that's fair.

The core of the board consists of a small FPGA chip (see UDO Super6!), which replaces the original CPU and other components of the oscillator section.
If you want to know it in detail, you can read all about it on Vecoven's site which is of course linked in the description.

After the hardware setup is completed a special firmware version has to be installed (currently 6.06, which works flawlessly) and the JX-8P with PWM is now ready with a new MIDI shine! (Sound examples + video of display with PWM parameter).

The new parameters are the following, and this is how it sounds: (examples for PWM sounds)

Pffff. Quite fat! Let's have a nightcap on that! And tell me one thing? Have you already subscribed to our channel and given us a fat filter sweep by booping the like button? It’s the right moment now! Yeah!

Yesss, Thank you! And if you've made it up to this point in your life, you'll definitely want a controller for your JX-8P! Which brings us to the next point!

The right Controller for the Roland JX-8P

Original controller PG-800 vs MPG-8 vs the others.
As I described earlier, the concept of Roland synthesizers back then was to offer the analog programming interface as an additional device. And as nice as the presets are, you quickly want some variety. With the basic digital interface of the JX, however, you have to know pretty much which parameter to press to get the appropriate results. And that is really no fun!

To unlock and understand the full sonic potential of these devices, a controller is a must. Because already the smallest changes to the presets show impressively on what thin ice these sounds were programmed at that time to sound as much as possible like a DX-7.

(Sound Examples)

Original Roland PG-800 Controller

From the beginning, the original PG-800 was not on the shortlist for me, because it is very difficult to get and then usually much more expensive than the synthesizer itself. And because I intended to use the Vecoven PWM mod, I wanted a solution that also takes the PWM parameters into account. But hold on: The Vecoven firmware has a workaround for that, too:
(FYI, this setting allows to set the PWM WIDTH with the DCO tune button. When you set the DCO waveform to PULS (on the PG800), the DCO TUNE becomes PWM WIDTH. To exit this mode, you can switch to another DCO waveform or simply modify the fine tune value (just do +1 -1 to get change and restore). This is a little trick to allow the PG800 to control the new PWM parameters.)

DTronics DT-800

The really fancy D-Tronics DT-800 from the Netherlands didn't give any details about this, so I quickly ended up with Retroaktiv from Colorado.

Retroaktiv MPG-8 vs Retroaktiv MPG-70mkII

They offer two controllers that are designed to work with the Vecoven mods. The massive MPG-70 mkIII is a bit over-engineered though, as it is specifically designed for modified JX10 and MKS-70s. The Vecoven mod for these synths has additional envelopes and LFOs which are all physically in place here as well. And according to Fred Vecoven, these features can unfortunately not be implemented in the JX-8P. Therefore, the MPG-8 came to me in the end!
The delivery from the USA was problem-free and fast and Rob from Retroaktiv is very kind and helpful!

So here it is: A small box with pots. A bit fiddly, but I might get new the MOOG-KNOB kit for it! (LAUGH!) Then it would sound even fatter!

The special thing here, is a PAGE2, on which you can address the PWM parameters. On the front panel this is unfortunately a bit confusing and hard to decipher for old farsighted men like me, because all the labels for the JX10/MKS-70 parameters are there as well. That's why I made those overlays. I'll link the PDF for self-printing in the description. I admit that my handicraft looks funny, but this is my way to understand and to learn. (EYEROLL).

To make this video even more practical for those who might have just bought such a controller for the Vecoven mod, here are the most important MIDI parameter settings to use the JX-8P as a master keyboard and at the same time the MPG-8 to send MIDI CC to the DAW without latencies and data mishmash. Thanks at this point to Fred for his patience with me! Once more, the bug sat in front of the device! :-)

Notes from the script:

Problem solved!
In the MIDI MIDI Menu I set SYSEX, APR and IPR to OFF. REALTIME = OFF. They are all useless for me when playing.

And then 28 CC to SEND instead of ON. Of course, that makes the whole difference!

Just a bit confusing!

So now I can record the CC from the programmer and use the JX as an additional master keyboard! And even though I had it set to LOCAL OFF the whole time, I had some latency when playing from another keyboard. Now that's no longer a problem either! Perfect!

This was also a little insight into the Vecoven MIDI menu.

And of course you can control the Vecoven-JX-8P with any other MIDI hardware controller now!

Price-Fun Ratio:

And now that everything is working properly, I guess only one question remains: how much is the fish, and for whom is it worth it?

Here are the facts:

The Vecoven Upgrade for both Firmware and PWM Modules is around 200 Euros. (Please consider that its not a company and Fred is doing it as a hobby!)

If you already have a JX-8P and don't want to butcher it with a soldering iron yourself you will need a tech. Here in Berlin my choice is Xtended. Kai is a real specialist and started to repair modify 303s and 909s back in the days. But be warned he is not the fastest! I paid around 390 Euros for a basic overhaul of the JX and the install of the two mods.

The MPG-8 is now at 350$. Plus shipping to Europe which was 55$. Plus 20% German Taxes! Einfuhrumsatzsteuer! Which was 80 Euros in my case!

So in total you will end up roundabout 1000 Euro/Dollars. Of course depending on your soldering skills and the choice of your controller.

And of course you need a JX-8P. If you are lucky, you can pick up usable ones for around 500 quid. But the trend for mint condition units in a flight case is more towards 1000. I would currently not pay more than 750 for a top condition unit in a case. Mine here, for example, has cost 550 euros in 2021 in its nifty self-built wooden case!

The same calculation can be made roughly for a JX-3P, for which there are also various mods to make it run smoother. JX10 and MKS-70 play in another league, are accordingly rare and do not necessarily sound better

All in all, you will definitely end up below the current vintage price of a Juno-106, let alone a Juno 60, MKS-80 or even a Jupiter.

In fact, there is currently no more affordable way to get the original polyphonic Roland analog sound of the 80s than with such a pimped JX. And here it doesn't matter if it's a 3 or an 8P. Get one while you can, especially if you are as fascinated by the sound as I am!

Another interesting video about this subject!

Alternatives to the Roland JX-8P

Because with alternatives it doesn't look so good on the current market, especially when the price is the crucial factor. And did I mention that in the first place the channel with these gear tests was born out of the search for a new polyphonic analog for my little revival home studio?

Analogues

The only synthesizers that have picked me up in a similar intense way so far have been the UDO Super6 and the Black Corporation's Xerxes. The latter even has DCOs just like its role model Elka Synthex. I got along with both of them immediately and started producing right away.

The Polybrute left me with a somewhat unfinished feeling due to its excessive complexity. In addition, the test unit always went out of tune when it was cold here and thus ruined a whole demo for me! So much for VCOs vs DCOs! Sorry Arturia! I like you anyway! And the new Jupiter from the V-Collection sounds quite useful as a replacement for on the road. Especially since some JX-8P presets are included, like 8P Soundtrack.

Deckard's Dream also had no chance in the analog segment! And without the ring modulator and Poly AT it's a total deception!

Digitals

The small polyphonic wavetable synths from my comparison video were of a different breed. If I had not such a fat disability pension, the Hydrasynth Explorer would have been my first choice in terms of a Polysynth. The Modwave and the Argonaut could not really delight in terms of sonic richness and are rather my tip for LOFI freaks. And slower envelopes than in the Argon8 have to be achieved first!

The biggest laugh, however, was the JX-08 Boutique version from Roland, which I honored with several blind-tasting videos and for which, if I'm honest, I also spontaneously bought this JX here in the first place.
Anyway, what Roland delivers there is nothing more than a tired knock-off. Watch it, too! A funny rant also came up, in which I built a whole minimal track out of the USB noise of the JX-08.

Conclusion

Well. Synthesizers are just like wine and many other good things in life: Quality either has its price and a special taste (which you can't always choose!) or an ambitious goal, often requires additional effort and research. Cheap alternatives are often more appearance than reality and rarely keep their promises. And if you buy cheap, you often buy twice. But you already know this whole Youtuber after-work philosophy!

And I could tell you for hours about these synths and how it was back in the 80s when these teenage dreams were still everywhere in the music stores and the radio played "Big in Japan" by Alphaville. But I don't know if I'm really ready for that.

Ouch! This video has become way too long! But if you still want to see more, check out my JX-8P playlist with the comparison videos, the rant and the demos! Enjoy!

See you in the next one! Peace!