DIY JPTR 8 clone *** New VCO Core Picture ***

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Boogie
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DIY JPTR 8 clone *** New VCO Core Picture ***

Post by Boogie » Sat Nov 10, 2018 11:15 am

2019-05-01 New VCO Core Picture
2019-04-28 New VCO Core Flatness
2019-04-27 VCO core Power Update
2019-04-14 Status Update
2019-03-10 Preference list updated
2019-03-08 MIDI IF assembled
2019-03-07 Audio PCB assembled
2019-03-07 some PCBs arrived
2019-03-07 2 VB Soundscape, List updated
2019-03-02 2 Voice Boards SOUNDSCAPE
2019-03-02 2 Voice Boards Audio File
2019-02-26 MIDI IF
2019-02-24 Audio Output IF Board
2019-02-17 Voice Board soldering update
2019-02-17 Updated List & Voice Board detail
2019-02-15 Updated Interest List
2019-01-28 Moving to the next step
2019-01-26 Band in the rain
2019-01-13 Interest List Updated
2019-01-12 Intermediate Test Board
2019-01-06 Updated
2019-01-02 V/Oct Tracking
2019-01-02 Interest list updated
2018-12-24 Merry Christmas
2018-12-18 About 320 components on the User IF
2018-12-18 Updated FP
2018-12-17 Updated list
2018-12-16 Preliminary User InterFace
2018-12-15 Updated interest list
2018-12-10 Free running Oscillators
2018-12-09 Some single voice pads
2018-12-08 Full voice module sounds
2018-12-08 First sound compare
2018-12-04 First Voice Board Populated
2018-12-01 Focus back on HW
2018-11-25 Approaching Final Format
2018-11-23 Enclosure outline
2018-11-21 Thank you for your feedback
2018-11-19 COntrol Panel help request
2018-11-18 Yes, it's a Jupiter 8 clone
2018-11-18 TH Voice Board Poll
2018-11-17 Voice PCBs Ordered
2018-11-16 New Audio
2018-11-12 The enclosure which it's not going to be
2018-11-11 New Sounds
2018-11-11 First Sounds
2018-11-11 Routed Voice Board V00.01
2018-11-10 Project launch



Hello all,

I've been rather silent during the last months as I've been working on some new project.

I will appologise up front, as I will not be offering all PCB's in kit form, but rather, as many of you already know, SMD populated.

Now, .... that is only for the voice boards and the processor board.

The controll board, or so to say, the User Interface, will be a mainly Through Hole Board with some SMD and will be measuring about 490 x 280 mm or some 19.3" x 11.0"

The pictures below may already give an indication where this is leading to.

All reactions welcome.

B rgds,
Boogie

Image

Image
Last edited by Boogie on Wed May 01, 2019 9:47 am, edited 67 times in total.
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

djs
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Post by djs » Sat Nov 10, 2018 11:20 am

Two things that I don't like about an ambika (and why I haven't gotten one) is that each voice board has it's own cpu, and that the front panel doesn't have enough knobs. What are your thoughts on this?
"Noise is what the Earth is made of" - David Bowie

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Post by Boogie » Sat Nov 10, 2018 11:33 am

Hello djs
Two things that I don't like about an ambika (and why I haven't gotten one) is that each voice board has it's own cpu, and that the front panel doesn't have enough knobs. What are your thoughts on this?
I'm sure I have at least good news for one of the topics and even maybe twice.
I can assure that the voice boards are fully analog no digital stuff except some select line for the analog switches.:bananaguitar:
I can also assure that the on board VCO's are not DCO's. :bananaguitar:

As the layout of the User Interface is not completed yet (though all functionality is known) I prefer not to publish the lay out yet, but here's a brief summary.
Synthesizer part
- 24 sliders
- 9 rotary knobs
- 13 push buttons

Patch Bay plus something I will disclose later
- 34 push buttons

Something else I will disclose later
- 19 push buttons
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

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StillNotWorking
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Post by StillNotWorking » Sat Nov 10, 2018 11:46 am

Let me guess. is it J8 inspired VCO? 8-)

Patch memory?

Number of user selectable modulation slots?

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Boogie
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Post by Boogie » Sat Nov 10, 2018 11:53 am

StillNotWorking wrote:Let me guess. is it J8 inspired VCO? 8-)
So true, yes. :tu:
Patch memory?
Yes, but with an extra.
Number of user selectable modulation slots?
This might be possible.
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

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Revok
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Post by Revok » Sat Nov 10, 2018 11:55 am

Really looking forward to this one :nana:

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Fitchie
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Post by Fitchie » Sat Nov 10, 2018 1:02 pm

This will be cool !
Following this thread from now on...
:grin:

v8pete
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Post by v8pete » Sat Nov 10, 2018 5:13 pm

Cool project, good luck!

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masterofstuff124
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Post by masterofstuff124 » Sat Nov 10, 2018 6:16 pm

Sounds very interesting. looking forward to it!

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Eric the Red
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Post by Eric the Red » Sun Nov 11, 2018 1:48 am

Looks intriguing. Following this to see where it goes.
Abandon all hope, ye who wiggle.

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Boogie
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Post by Boogie » Sun Nov 11, 2018 8:04 am

Hello all,

thanks for the motivation.

Here's a screendump of the routed Voice Board Proto.
The green plane in approx the middle of the board is a low impedance plane to couple a split power plane in one of the inner layers.
One another of course to avoid voltage drops in the power distribution vs. using thin traces.

Image
Last edited by Boogie on Sun Nov 11, 2018 11:34 am, edited 1 time in total.
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

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Post by Boogie » Sun Nov 11, 2018 10:23 am

And here's a first sound file.

It's the original Jupiter 8 LPF with a IR3109
and
a Home Brewn filter.
One of them is on the left channel, the other on the right channel.

Single voice, two oscillators (one can hear them fade) (fading by intentional detune)
Only effect is Q_Base Reverb, no additional processing.
Only playing with cut-off frequency, no Resonance feedback, thus pure 4th order LPF.

Have fun figuring out which channel is the original. I hope it's a chalenge and not too easy. :roll:
All feedback welcome.

https://soundcloud.com/boo-gie-879149310/filter-compare
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

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New Sounds

Post by Boogie » Sun Nov 11, 2018 1:28 pm

Here's another one.

Single Voice Multi Track Recording
Drums are my TR808 clone.
Only post processing some QBase reverb

Opening chords of Jump (Van Halen)

https://soundcloud.com/boo-gie-879149310/jump
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

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Post by Fitchie » Sun Nov 11, 2018 2:11 pm

Ohhh yeah, back to the 80's !
Fat sounds, cross-modulation and velocity controlled resonance. 8-)

I like !

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grenert
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Post by grenert » Sun Nov 11, 2018 3:03 pm

Very cool, Boogie! It sounds great! Nice plug for your TR clone, too :hihi:

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tobb
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Post by tobb » Sun Nov 11, 2018 3:22 pm

Boogie wrote:
Have fun figuring out which channel is the original. I hope it's a chalenge and not too easy. :roll:
The distinct Roland filter sound lays in the sounds with resonance and this is very enhanced when played poly.

And zero reverb.

Its impossible to compare w/o these elements.

PS: With all the skills you have i would do the vco's Tzero then a whole new and large sound palette is added to your clone and suddenly your synth becomes not a clone but the first one analog TZ poly- synth on the planet.

Add a multimode vcf and another vco = bey bey Moog One

Add filter fm (vco-to cutoff) (MUST HAVE) = bey bey P5

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Post by Boogie » Sun Nov 11, 2018 4:51 pm

Hey Revok
Good to see you here too!

also to grenert
Nice to see you again !
Thanks for the feedback :chug:
I hope the MiniP7 is bringing lots of fun to you.

For all new supporters, thanks for being here !

Hey tobb
nice to see you again too !

Same as last time,
your analysis is very to the point and much appreciated ! :tu:

The polyphonic sound is going to take a while, as in at least 6-8 weeks. And then probably just some 2-3 voices not 8 yet. PCBs to be ordered debugged etc... (schematics to be updated with your newly provided info ;-) )

I must admit, the reverb is nasty.
I'll post another sound file, say in a about a couple days to a week, without the reverb and with resonance but still single voice.
Let's hope differentiating will still be tough.

The Tzero would also mean linear FM which I didn't foresee yet.

You've introduced a good idea I wasn't thinking of, thank you. :chug:
Fortunately, it's not too late to make it happen.
I'll play a bit with one another and will find out how it goes. If fine, I'll post in time.
Add filter fm (vco-to cutoff) (MUST HAVE) = bey bey P5
Is already foreseen, (VCO or LFO) but not used in the sound files above.
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

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Post by tobb » Mon Nov 12, 2018 5:26 am

Boogie wrote:
Add filter fm (vco-to cutoff) (MUST HAVE) = bey bey P5
Is already foreseen, (VCO or LFO) but not used in the sound files above.
Excellent but you have to have both at same time,lfo is to make movements to the sound,filter fm is to obtain another VCF sound/grain: with closed cutoff and the reso a bit boosted you get organic sounds.

And i just would route fixed a sine or triangle to the filter fm independent of the selected vco wave.

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Post by Boogie » Mon Nov 12, 2018 5:40 am

And i just would route fixed a sine or triangle to the filter fm independent of the selected vco wave.
OK,
if I understand correct, you would use a seperate VCO to be the TZ modulation source. That's a good idea and simplifies one another.

Is my interpretation correct ?

[/quote]
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

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Post by aabbcc » Mon Nov 12, 2018 8:04 am

YES :guinness:

This sounds very interesting

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tobb
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Post by tobb » Mon Nov 12, 2018 8:10 am

Boogie wrote:
And i just would route fixed a sine or triangle to the filter fm independent of the selected vco wave.
OK,
if I understand correct, you would use a seperate VCO to be the TZ modulation source. That's a good idea and simplifies one another.

Is my interpretation correct ?
[/quote]

No,i mean for the FM routing from a vco to the filter cutoff the best effect is obtained with a sine or triangle,the other waves mess up to much and it getting crunchy,with a sine or triangle the effect is subtle and just enough to simulate a light overblown effect or making sounding your filter ARP-ish. make sure the fm signal depth is large enough,so still extreme mod is posibel (i have a Schmidt synth that also have FM mod from the vco's to vcf's but the mod amount is not deep enough)

So let say if you have two vco's in the synth chain each with x waveforms,just route the sine or triangle from one of them to the filter cutoff mod matrix,that way you can use let say saw or square from that vco to the fvc audio in,but the triangle or sine of the same vco will always be the modulation waveform to the filter.

You have to test but i think its best to use as mod source vco 1,because if you do also fm between osc, OSC2 -> 1, pitch of vco 2 will in most cases (other then doing flipperbox sounds) higher then pitch of vco 1

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tobb
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Post by tobb » Mon Nov 12, 2018 8:31 am

Also, i would design the front panel with rotating knobs rather then a combi with faders,because if its a rack enclosure vertical fader controls is less pleasing to tweak VS knobs,faders are great if its desktop or flat/horizontal synth enclosure.

Also it better not to promote the synth as a Jupiter-8 clone but as a new synth with more features that can emulate JP-8 type sounds.

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Post by StillNotWorking » Mon Nov 12, 2018 8:46 am

tobb wrote:Also, i would design the front panel with rotating knobs rather then a combi with faders,because if its a rack enclosure vertical fader controls is less pleasing to tweak VS knobs,faders are great if its desktop or flat/horizontal synth enclosure.

Also it better not to promote the synth as a Jupiter-8 clone but as a new synth with more features that can emulate JP-8 type sounds.
Fully agree on this. But often feel we are a minority saying this. Maybe people forget synths might have a life outside the premium ergometric work space when they calls for faders.

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Post by Boogie » Mon Nov 12, 2018 8:47 am

Hello tobb
better not to promote the synth as a Jupiter-8 clone but as a new synth with more features that can emulate JP-8 type sounds
Exactly my idea as well. I was thinking on Nabla Instruments ... (to be disclosed later)
As one of the initial questions in this thread was ifthe VCOs would be JPTR 8 derivatives, I had to say yes, as they are.
But for final product, it will be an expanded version of the JPTR 8, so another name with a 'blink of the eye' towards JPTR 8 came across my mind.

About the frontpanel,
I will disclose more later, but I can already inform that the first version is not really going in the direction of Eurorack but rather stand alone.

When moving to Eurorack, yes I absolutely agree,
keep the knobs well accessable and then rotary is easier to work with if indicators are 'clean' visible.
-------------------------------------------------------
“Digital generated ‘analog’, is missing its analog soul and therefore isn’t analog any more.”
Jupiter 8 clone: https://www.muffwiggler.com/forum/viewt ... p?t=209322
Minipops 7 clone: https://www.muffwiggler.com/forum/viewt ... p?t=199360
ClapTrap clone: https://www.muffwiggler.com/forum/viewt ... p?t=202248
www.nabla-instruments.com

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Post by m.o » Mon Nov 12, 2018 10:39 am

How is your signal routing done, on the voice board or on processor board?

Which waveforms are available from the vcos (square, saw, triangle?, sine?), and how are you switching them (external to voice board or externally)?

Are the levels from each oscillator controllable by a vca for each vco, or simpler full-half-none scheme (like Oberheim OBx)?

It looks like there are 3 tempco resistors, third one if for the filter?

Are there any provisions for some auto-calibration?

How many CVs do you end up with per voice?

(Sorry if some questions are a bit nosey ) :hihi:

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