[Build Thread] Jasper, an EDP Wasp Clone

From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive!

Moderators: Joe., lisa, luketeaford, Kent

Post Reply
theboytheycalljonny
Learning to Wiggle
Posts: 2
Joined: Mon Dec 17, 2018 6:56 pm
Location: Derry

Jasper Case Option

Post by theboytheycalljonny » Mon Dec 17, 2018 7:08 pm

Hey folks

Just finished a Jasper build and thought I'd share what i used for a case.

It's literally an old readers digest 'Learn Italian' cassette series box and it fits perfectly! It cost me £3 in a charity shop. They're on eBay for about £15.

All i had to do is drill a load of holes for the power, ins and outs etc. I used standoffs to raise the PCB up a little.

Here's a picture


Here's a link to eBay for the same type of case

https://www.ebay.co.uk/itm/Readers-Dige ... :rk:5:pf:0
You do not have the required permissions to view the files attached to this post.

User avatar
Bamboombaps
Wiggling with Experience
Posts: 386
Joined: Wed Sep 16, 2015 7:14 am
Location: Glasgow

Post by Bamboombaps » Tue Dec 18, 2018 3:40 pm

Hey all trying to resurrect a sickly build.

Here's some issues-
When turning on it starts off silent and sound gradually build over about 4mins
When the vca env is switched it goes very quiet . I can still hear the ticking if the control env. Section and the other sections way in the background
Constant sound. It thinks a key is constantly depressed.
Keyboard erratic. No amount of messing with the sensitivity seems to get the lower quarter of the keyboard to function at all.

:help:

User avatar
balbibou
Common Wiggler
Posts: 104
Joined: Wed Sep 17, 2014 2:35 am
Location: France, Lyon

Post by balbibou » Wed Dec 26, 2018 9:02 am

During the calibration process of 'VCO separation trimmer' (page 40/41) it is asked to 'Turn the Bend control fully clockwise. If the oscillators start to beat more quickly or more slowly, then adjust the trimmer to get the slow beating again.'
Well for me just by touching or brushing the rotary part/case of the osc 2 pitch pot it changes this beating effect. Is it a ground issue ? What should I look for ?
Last edited by balbibou on Wed Jan 16, 2019 6:58 am, edited 3 times in total.

johnnym
Learning to Wiggle
Posts: 12
Joined: Thu Nov 16, 2017 2:10 pm
Location: Northants, England

Post by johnnym » Wed Dec 26, 2018 5:55 pm

I’ve just started my build on this and looking at the v2 construction guide it clearly shows a space for a cap between R128 and IC33 unpopulated at the bottom of page 10 which assumed would be for a 0.1uf cap. Then on the bottom 11 it shows it populated with something. I’ve already got all 38 0.1uf caps in place so what goes here? :despair:

User avatar
duff
Veteran Wiggler
Posts: 748
Joined: Sun Mar 10, 2013 2:21 pm
Location: UK

Post by duff » Thu Dec 27, 2018 3:01 am

johnnym wrote:I’ve just started my build on this and looking at the v2 construction guide it clearly shows a space for a cap between R128 and IC33 unpopulated at the bottom of page 10 which assumed would be for a 0.1uf cap. Then on the bottom 11 it shows it populated with something. I’ve already got all 38 0.1uf caps in place so what goes here? :despair:
That is a 0.1uf decoupling cap.

johnnym
Learning to Wiggle
Posts: 12
Joined: Thu Nov 16, 2017 2:10 pm
Location: Northants, England

Post by johnnym » Thu Dec 27, 2018 5:14 am

duff wrote:
That is a 0.1uf decoupling cap.
Thanks, so the BOM should say 39 caps for this then? I’ve double checked I’ve not got any of the other ceramic caps in the wrong place and all looks OK there.

User avatar
duff
Veteran Wiggler
Posts: 748
Joined: Sun Mar 10, 2013 2:21 pm
Location: UK

Post by duff » Thu Dec 27, 2018 5:41 am

johnnym wrote:
duff wrote:
That is a 0.1uf decoupling cap.
Thanks, so the BOM should say 39 caps for this then? I’ve double checked I’ve not got any of the other ceramic caps in the wrong place and all looks OK there.
Yeah, pretty sure you need 39 0.1 uf caps and the BOM was one short orignally - although it has been a lot time since I built mine and there have been a few PCB revisions since then. I thought Jason had updated the BOM, but perhaps not.

johnnym
Learning to Wiggle
Posts: 12
Joined: Thu Nov 16, 2017 2:10 pm
Location: Northants, England

Post by johnnym » Thu Dec 27, 2018 6:32 am

duff wrote: Yeah, pretty sure you need 39 0.1 uf caps and the BOM was one short orignally - although it has been a lot time since I built mine and there have been a few PCB revisions since then. I thought Jason had updated the BOM, but perhaps not.
Great, thanks for your help

User avatar
duff
Veteran Wiggler
Posts: 748
Joined: Sun Mar 10, 2013 2:21 pm
Location: UK

Post by duff » Thu Dec 27, 2018 8:28 am

balbibou wrote:During the calibration process of 'VCO separation trimmer' (page 40/41) it is asked to 'Turn the Bend control fully clockwise. If the oscillators start to beat more quickly or more slowly, then adjust the trimmer to get the slow beating again.'
Well for me just by touching or brushing the rotary part/case of the osc 2 pitch pot it changes this beating effect. Is it a ground issue ? What should I look for ?
The case/bodyof the pot should be isolated from the pins so touching or brushing it should have no effect. Could you have a defective pot?

User avatar
balbibou
Common Wiggler
Posts: 104
Joined: Wed Sep 17, 2014 2:35 am
Location: France, Lyon

Post by balbibou » Thu Dec 27, 2018 9:00 am

The case/bodyof the pot should be isolated from the pins so touching or brushing it should have no effect. Could you have a defective pot?
Ordered one yesterday. This is the only thing that comes to my mind as I don't have electronic knowledge.
Last edited by balbibou on Wed Jan 16, 2019 6:58 am, edited 2 times in total.

adrien-19
1-Post Wiggler
Posts: 1
Joined: Thu Dec 27, 2018 8:45 am
Location: Swiss

control env. problem :(

Post by adrien-19 » Thu Dec 27, 2018 9:17 am

Hello everyone,

I write on this forum because I just finished my jasper, and I have a problem with the control env. , here are videos of my problem:



https://www.youtube.com/watch?v=vvqxhwO ... YE3wStWPHw

and the second with a MIDI input (which confirms that the problem of not coming from the keyboard)



https://www.youtube.com/watch?v=uuB38il ... Hw&index=1

Randomly the envelope activates twice in succession. There is surely a problem in the detection of the note, maybe it is an IC that does not work well.

Maybe it's normal, but I have doubts. I wanted to know if any of you can tell me which parts I should resoldering or which IC I should change.

 Thank you in advance !

User avatar
sixbyseven
Common Wiggler
Posts: 61
Joined: Tue Sep 20, 2016 2:43 pm
Location: Hamilton Ontario
Contact:

Rack Mounted Wasp

Post by sixbyseven » Fri Jan 04, 2019 8:09 am

I built a wooden box with one end open, then used 19" rack drawer slides to install the Jasper into one of my synth racks. The midi, power and audio outs are all wired off the back.

It is actually very useable in the configuration, and makes it easier to orchestrate with other synths manually or through midi.

Image

Callockard
Learning to Wiggle
Posts: 4
Joined: Tue Dec 18, 2018 9:25 pm
Location: USA

Post by Callockard » Sat Jan 05, 2019 8:18 pm

Hi, Anyone else notice the resonance seems (sounds) like it has a higher value when set to zero? In other words, filter has some resonance when Q is set to zero...

paddodust
1-Post Wiggler
Posts: 1
Joined: Wed Feb 20, 2019 12:33 pm
Location: Uk

Partial function of keyboard

Post by paddodust » Wed Feb 20, 2019 1:35 pm

Hi..everyone

First post so be Kind :hihi:

Ok so I built myself a jasper and powered it on... everything works as it should, but the keyboard is giving off wierd vibes!!
I seem to get the 3 octaves on the board to be correct audiowise but the semitones in between do nothing.. That is to say.. only a few notes play and the rest are dead.
I figure it must be something to do with the note decoding, but I can't figure it out from the drawings
:bang:
Checked my sockets and soldering and all looks ok.. I did run over all of them with a magnifying glass to determine if I missed a pin or there was a bridge.. but nada..

Much Love to anyone who's got any insight...

Patrick

User avatar
Bodo1967
Veteran Wiggler
Posts: 559
Joined: Wed Aug 10, 2016 2:27 pm
Location: Germany

Post by Bodo1967 » Thu Feb 21, 2019 5:01 am

It's been a while since I built mine, but I do remember there are quite a few test points where you're supposed to check voltages. Iirc, those can be found in the original WASP service manual, which can be used for the Jasper as well.

Are these voltages alright in yours?

If not, or if you haven't checked them yet, that might be a goood point to start.

I also had a problem at first - mine only played one octave but did so twice (as in, jumped from middle B to low C instead of middle C when playing the notes in an upward order, then repeated the lower octave). Turned out to be a small solder blob on the bottom side of the PCB where the ribbon cable is connected.
... why buy it for $100 when you can build it yourself for $150?

mightymike1978
1-Post Wiggler
Posts: 1
Joined: Tue Mar 20, 2018 10:27 am
Location: Koenigswinter, Germany

Re: Jasper Case Option

Post by mightymike1978 » Tue Feb 26, 2019 11:10 am

Thanx, great idea!!!

Please show us a picture of it, if you got any! ;-)

Best regards
Mighty
theboytheycalljonny wrote:Hey folks

Just finished a Jasper build and thought I'd share what i used for a case.

It's literally an old readers digest 'Learn Italian' cassette series box and it fits perfectly! It cost me £3 in a charity shop. They're on eBay for about £15.

All i had to do is drill a load of holes for the power, ins and outs etc. I used standoffs to raise the PCB up a little.

Here's a picture


Here's a link to eBay for the same type of case

https://www.ebay.co.uk/itm/Readers-Dige ... :rk:5:pf:0

User avatar
hox3d
Common Wiggler
Posts: 108
Joined: Fri Feb 02, 2018 6:30 am
Location: Grenoble, Alps

Post by hox3d » Tue Feb 26, 2019 1:18 pm

Hey team.

I wanted to build a Jasper just to make a wooden case.
Since I don't really trust my skill to make such a thing, I decided to reduce the risk by modeling it prior to do it.

So, here is the thing:
Image

I must say I just learned Blender just for that one.
That's a little bit overkill but yeah, I could learn something.
It's not perfect, it's missing switches and screws... But that's enough for my purposes.

Let me know what you think of it!
Matte-fueled habits

User avatar
jersupereq
Common Wiggler
Posts: 223
Joined: Sat Aug 16, 2008 9:24 pm
Location: SF

Post by jersupereq » Tue Feb 26, 2019 1:20 pm

Beautiful! :hail:

User avatar
devinw1
Super Deluxe Wiggler
Posts: 1202
Joined: Tue Aug 07, 2018 11:20 am
Location: Portland, OR
Contact:

Post by devinw1 » Tue Feb 26, 2019 5:08 pm

hox3d looks good, but maybe my eyes deceive me but the front lip is protruding beyond the plane of the key suface? If so, I would make it flush or even down maybe .03"-05" so it's not a hindrance to play.

User avatar
hox3d
Common Wiggler
Posts: 108
Joined: Fri Feb 02, 2018 6:30 am
Location: Grenoble, Alps

Post by hox3d » Tue Feb 26, 2019 5:58 pm

It's supposed to be right at the same level, the picture is not that clear indeed... The two models are so close that you can't see any gap in-between.
But yeah, maybe a small angle to add "access" to the keys?

It's not a perfect model ahah. I tried my best but at some point it was like "well, I can't see it, let's forget about this detail".
For instance, I wanted to make all corners a little bit more "roundish".
Matte-fueled habits

User avatar
makhho
Common Wiggler
Posts: 158
Joined: Mon Feb 05, 2018 11:53 am

Post by makhho » Tue Feb 26, 2019 10:59 pm

Looks good indeed, hox3d. IF you do happen to do a run of these, then I'd be interested in one.

How thick would the back of the case be? Curious because I'd likely drill holes to accommodate Jason's MIDI board design.

User avatar
kragg
Wiggling with Experience
Posts: 455
Joined: Thu Dec 15, 2011 2:42 pm
Location: Nemo Point

Post by kragg » Thu Apr 11, 2019 4:50 pm

makhho wrote:It is strange because everything functionally seems to be working, only problem is that I must have the volume on the JASPER and mixer/monitors jacked really high.

Noise, different oscillator shapes, FT", Q / FILTER, LFO waveform, etc. all seem to be working, I just have to boost the hell out of the signal to hear anything.

Looked over caps and resistor values near the line out and phones, and nothing looks wrong... :despair:

EDIT -- FIXED. Wow -- completely spaced out on the external trigger mod.

I wasn't getting line out from the minijack socket because I didn't have a header bridging the T to S on the external mod. Ugh. Okay.
If anyone runs into this issue hopefully this helps.
Thank you , this helped me indeed :tu:

bujbot1
Learning to Wiggle
Posts: 14
Joined: Mon Jul 06, 2015 2:27 pm
Location: Canada

Post by bujbot1 » Tue Apr 30, 2019 12:05 am

Hey,

Just finished my build. Went really well and I love the sound of this thing!

Like others here I noticed more noise than I wanted out of the "phones" jack. Here's what I did to fix it:

Regulated the power supply in. I had a slight hum that I didn't like on the phones jack. I didn't want to touch the Jasper internally so I made a 9v regulator with filter caps as a dongle. That cleaned the hum and some of the other noise.

I turned the LM386 amplifier down a bit. It sounded like it was picking up some high freq logic noise and was excessively loud. So I solder 6k resistor from input to ground on the chip itself (didn't want to touch the jasper internals again).

Now the phones jack is clean and hotter than the line out (though only by about 50-75%). The speaker is probably a touch quieter than I would like. If I did it again I would likely use 10-15kohms instead which would make the amp a bit louder.

Maybe this will help someone, I dunno! Either way, thank you jasonl, this is incredible all around!

User avatar
grizzle
Common Wiggler
Posts: 119
Joined: Sat Feb 26, 2011 4:35 pm

Post by grizzle » Fri May 03, 2019 1:16 pm

Hey all,

The build guide says to solder in TR1 and TR2 bent over flush against the PCB to avoid any shorts but I noticed both transistors have been moved on the latest PCB. Do they still need to be installed bent flush or can they be soldered in without bending the legs now?

Cheers,
Alex
Tunes-----> apartmentfox.bandcamp.com

User avatar
gslug
Common Wiggler
Posts: 182
Joined: Tue May 07, 2013 10:30 pm
Location: Surrey, UK

Post by gslug » Thu May 09, 2019 4:10 pm

Got mine built and it all seemed so easy.... but I have filter problems. I only get an output on Notch or High Pass. Low and Band Pass are (almost) silent. I've had a look at the Wasp service manual and seen that this can be symptomatic of oscillator 1 not working as it provides the keyboard voltage, but oscillator 1 is working in my case and I'm getting around 0.6V on pin 13 of IC 12. Any ideas?

Scratch that. After much poking around with a scope it turns out I've got a duff rotary switch. That's going to be fun to desolder....
One day I'll get an avatar!

Post Reply

Return to “Music Tech DIY”