Erica Synths DIY Bassline

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

Moderators: lisa, luketeaford, Kent, Joe.

Post Reply
User avatar
Girts23
Wiggling with Experience
Posts: 377
Joined: Mon May 20, 2013 2:22 am

Erica Synths DIY Bassline

Post by Girts23 » Mon Jul 23, 2018 6:48 am

Dear colleagues, inspired by super-positive response to our upcoming Bassline module in the Techno System, we decided to develop a lite version for DIYers! Erica Synths Bassline is full analogue synth voice module for ultimate acid basslines. It features highly stable AS3340-based VCO with three waveforms, a filter inspired by Erica Synths Acidbox, distinct overdrive circuit and unique feature – transistor-based suboscillator. Accent provides more expression to the bassline, by adding volume and opening the VCF slightly.

Image

FEATURES:
Full analogue circuit
Great 1V/oct tracking
Simultaneous Triangle, Square and Master outputs
Accent
Overdrive
Transistor-based suboscillator
VCF and VCA decay envelopes
LP/BP VCF
External VCO FM and VCF cutoff CV inputs

DIY kits starting from 50EUR are available in three versions:
1) Set of 2 PCBs + rare ICs + mechanical parts (PCB connectors and spacer),
2) Set of 2 PCBs + rare ICs + mechanical parts (PCB connectors and spacer)+ panel,
3) Full kit.

Check out the Erica Synths webshop! Also you'll find assembly instructions there.

And here's a great demo from Synth DIY Guy!

[video][/video]

Enjoy!

User avatar
TheMentat
Common Wiggler
Posts: 183
Joined: Thu Nov 30, 2017 1:48 am
Location: Ocean Park

Post by TheMentat » Thu Jul 26, 2018 2:06 am

That thing sounds fantastic!

sekm
Learning to Wiggle
Posts: 6
Joined: Tue May 15, 2018 11:48 pm
Location: San Francisco

Post by sekm » Sat Jul 28, 2018 11:41 pm

Looks great, I just ordered a couple other kits from you guys, might have to grab this one too when I'm done!

User avatar
sicpaul
Wiggling with Experience
Posts: 342
Joined: Thu Dec 22, 2011 9:28 am
Location: Berlin

Post by sicpaul » Wed Aug 08, 2018 2:51 pm

Hi Girts,

as i did order a PCB-set (and some other stuff) i took a look at the BOM leaving one question: What is the difference between the two 250k Pots?
I usually order the 9mm pots at TAYDA, so RD901/2 packages don't tell me too much. Are you able to give me a hint?
Best regards
(sic)paul

User avatar
Girts23
Wiggling with Experience
Posts: 377
Joined: Mon May 20, 2013 2:22 am

Post by Girts23 » Mon Aug 13, 2018 3:50 pm

sicpaul wrote:Hi Girts,

as i did order a PCB-set (and some other stuff) i took a look at the BOM leaving one question: What is the difference between the two 250k Pots?
I usually order the 9mm pots at TAYDA, so RD901/2 packages don't tell me too much. Are you able to give me a hint?
Best regards
(sic)paul
One of them is stereo - dual gang

User avatar
pod
Learning to Wiggle
Posts: 2
Joined: Sun Jun 03, 2018 2:38 pm

Doesn't work! What have I done wrong?

Post by pod » Wed Dec 12, 2018 8:55 am

Hey guys,

I just finished my build and I am getting a weird output from main out. On my scope it kinda looks like a very small and weird square, and no noise comes out!

I have triangle and square on the direct outputs, but they seem very high pitched. Adjusting the tuning screw doesn't seem to make a whole heap of difference.

I was super careful when placing, but obviously I have placed something wrong..any pointers? I have DMM and oscilloscope, but don't really know where to start!

Sorry!

jake :bang:

aleszylder
Learning to Wiggle
Posts: 9
Joined: Wed May 23, 2012 6:54 am

Re: Doesn't work! What have I done wrong?

Post by aleszylder » Fri Dec 28, 2018 2:37 am

pod wrote:Hey guys,

I just finished my build and I am getting a weird output from main out. On my scope it kinda looks like a very small and weird square, and no noise comes out!

I have triangle and square on the direct outputs, but they seem very high pitched. Adjusting the tuning screw doesn't seem to make a whole heap of difference.

I was super careful when placing, but obviously I have placed something wrong..any pointers? I have DMM and oscilloscope, but don't really know where to start!
I am having the same problem: only a very high pitched tone coming out of all outputs...

Landsphere
Learning to Wiggle
Posts: 11
Joined: Fri May 05, 2017 4:06 pm
Location: united kingdom

Bassline DIY build problem.

Post by Landsphere » Mon Jun 10, 2019 6:08 am

Hey people..

I finished my build a couple of days ago and have since spent the time trying to problem solve it. Upon powering it up, I get the VCA Env LED flashing (as well as flashing on some of my other modules)..

Given the amount of resisitors, I double checked to make sure they were all located properly (I found one wrong which I have since corrected).
All diodes are in the correct way.
All electrolytic caps are in the correct way round.
I have continuity checked all the IC sockets for good connection to the board.
I have continuity checked the headers to check connection between both boards.

If I have just the control board plugged in, the rest of my system doesn't flash, so Im inclined to think the issue is on the main board, would you agree?
Any ideas for other things I could check?

Thanks.. Rob
You do not have the required permissions to view the files attached to this post.

User avatar
Girts23
Wiggling with Experience
Posts: 377
Joined: Mon May 20, 2013 2:22 am

Re: Bassline DIY build problem.

Post by Girts23 » Mon Jun 10, 2019 10:51 am

hi, Rob!
Drop an email to our support - info@ericasynths.lv. We’ll try figure out what’s wrong.

Girts

User avatar
cathmart
Common Wiggler
Posts: 84
Joined: Thu Nov 30, 2017 6:13 pm
Location: Sydney

Post by cathmart » Sun Jun 30, 2019 9:16 pm

quick question...for some reson I don't have a single gang B250 k Pot, I do have a B 500k pot, will that work in the R8..VCF envelope?

PrinceHal9000
Learning to Wiggle
Posts: 2
Joined: Thu Jun 13, 2019 10:40 am
Location: Brooklyn

1V/Oct Tracking Troubleshooting

Post by PrinceHal9000 » Fri Aug 23, 2019 3:51 pm

I sent this to the good people at Erica, but wanted to post here to see if anyone had any insight:

I'm having a bit of trouble with 1V/Oct tracking on the Bassline:

No matter how much I adjust the "scale" trimpot, I can't seem to get a full octave per Volt during calibration.

While adjusting the R10 Scale Trimpot:
AT FULL CW:
C4 = 261 Hz
C5 = 478 Hz

AT FULL CCW:
C4 = 261 Hz
C5 = 492 Hz

I can't quite get a full octave.
Any idea what could be wrong?

Dokolasa
1-Post Wiggler
Posts: 1
Joined: Fri Jun 15, 2018 5:38 pm
Location: Denver

Re: 1V/Oct Tracking Troubleshooting

Post by Dokolasa » Mon Sep 23, 2019 5:02 pm

*UPDATE* talked to the poster above, who had already contacted Erica & got it sorted out. Apparently (at least in two cases) the kit included an incorrect trimpot for R10 (the brass screw by the Tune knob), a Bourns 3296W-1-102, with only 1k resistance. I took mine apart & sure enough, it was built with a 102... It should be replaced with a 3296W-1-103, which has 10k resistance. Hope this helps anybody else who can't get to a full octave upon calibration!

I'm having the same problem with a DIY build I picked up already assembled... did you ever get it figured out?
PrinceHal9000 wrote:I sent this to the good people at Erica, but wanted to post here to see if anyone had any insight:

I'm having a bit of trouble with 1V/Oct tracking on the Bassline:

No matter how much I adjust the "scale" trimpot, I can't seem to get a full octave per Volt during calibration.

While adjusting the R10 Scale Trimpot:
AT FULL CW:
C4 = 261 Hz
C5 = 478 Hz

AT FULL CCW:
C4 = 261 Hz
C5 = 492 Hz

I can't quite get a full octave.
Any idea what could be wrong?

Bankside
1-Post Wiggler
Posts: 1
Joined: Thu Jan 30, 2020 3:57 pm

Re: Erica Synths DIY Bassline

Post by Bankside » Thu Jan 30, 2020 4:30 pm

Hi People
I'm also having trouble with the VCA output, there's a very low and noisy sound from the main output .
i've contact the so called "support team" but they're pretty much inefficient....they asked me 25€/h to check out the problem :foul:

scottdanesi
Learning to Wiggle
Posts: 3
Joined: Tue Jul 10, 2018 9:44 am
Location: Chicago

Re: Erica Synths DIY Bassline

Post by scottdanesi » Fri Feb 07, 2020 9:47 pm

Hey Everyone!

Just got my Bassline all assembled. I am having an issue though as I am getting no sound out of the module at all. The LEDs are doing what they are supposed to though when opening and closing the VCA. I even sent it a gate just to see if it would react to that and it does seem to flash the LEDs properly, just no sound or voltage out. I also checked the output with an oscilloscope, and nothing. Any ideas what I should check? Thank you!
--Scott

User avatar
ntrm
Learning to Wiggle
Posts: 19
Joined: Fri Jan 30, 2015 4:58 am
Location: Estonia

Re: Erica Synths DIY Bassline

Post by ntrm » Mon Feb 10, 2020 3:42 am

scottdanesi wrote:
Fri Feb 07, 2020 9:47 pm
Hey Everyone!

Just got my Bassline all assembled. I am having an issue though as I am getting no sound out of the module at all. The LEDs are doing what they are supposed to though when opening and closing the VCA. I even sent it a gate just to see if it would react to that and it does seem to flash the LEDs properly, just no sound or voltage out. I also checked the output with an oscilloscope, and nothing. Any ideas what I should check? Thank you!
--Scott
No output from triangle or square outs also? Are all IC inserted in correct way? Probe CEM3340 (DA10) pins 4, 8 and 10 to see if it is working and outputting the correct waveforms. Then probe DA4 and DA11 (LM13700).


Just finished building the module. All seemed fine and working but after playing with it for some time, discovered that square and triangle waveform sound similar?! And also DA4 was getting vary warm and when probing the tri and sqr outs, they were the same. After some debugging found that there was a short somewhere on the controller pcb, between sqr and tri traces on the way from XS11/XS9 pin headers to the waveform selection switch :hmm: :mad: So I cut the sqr trace near the switch and also near the pin header and ran a mod wire between them. After this everything worked correctly.

marcusgho
Learning to Wiggle
Posts: 3
Joined: Mon Apr 08, 2019 10:36 am
Location: Singapore

Re: Erica Synths DIY Bassline

Post by marcusgho » Fri Mar 20, 2020 10:09 pm

I just purchased and completed a build of the DIY Bassline. Mine is the DIYBASS2 Version

I am having some issues with the Filter Section of the Module

I initially left Trimpot R140 around 12 o'clock and the jumper set to bottom pins (Cutoff CV Potentiometer set to simple attenuator). The entire filter section does not work. Cutoff and Resonance Knob has no effect on the sound, However I can see the VCF Envelope and the VCF LED is responding to the gate

Next, I started adjusting Trimpot R140 and it sort of works only when i turned it fully clockwise. In this scenario, everything sorta works but i get limited range on the Cutoff. Can you please tell me if this is normal behavior? is there anything else i should be looking out for?


Thanks

BarneyRubble
Learning to Wiggle
Posts: 29
Joined: Sun Jul 31, 2016 11:32 am
Location: Scotland

Mainboard Short to Ground: DIY Baseline v2.0 - FIXED

Post by BarneyRubble » Fri Jun 12, 2020 6:51 am

I have just finished building my second DIYBASS2 - The second build main board negative rail is shorting to ground and I think it may be a fault on the track. Looked at the board under a microscope and tested as far as possible with meter. After three days of checking I'm all out of ideas.

Does anyone have high res pictures of an unpopulated DIY Bassline v2.0 Main board front and back that they could share. I could then visually trace the negative lines to try to isolate the problem.

I've ordered a second board from Erica Synths direct in case I can't fix the short.
I verified that the control board is ok by swapping control boards with the known good main board.

Any help or advice welcome

Thanks

See post below

BarneyRubble
Learning to Wiggle
Posts: 29
Joined: Sun Jul 31, 2016 11:32 am
Location: Scotland

Re:Mainboard Short to Ground:DIY Baseline v2.0 - FIXED

Post by BarneyRubble » Sat Jun 13, 2020 8:08 am

Typical, after spending days looking at the board with no joy and posting here for help. I had another go this morning and here is what I found. Pictures are pretty self explanatory. Not sure whether to be happy or not seems I just spent money needlessly on a spare third mainboard. I'll ping off an email to support and see what they say.

At least the Baseline is working now!

This is my known good Mainboard that I used for comparison.
Screenshot 2020-06-13 at 11.52.59.png
This is my Mainboard with the faulty trace.
Screenshot 2020-06-13 at 11.51.35.png
This is the bodge - scraped off the trace joining minus volts to ground.
Screenshot 2020-06-13 at 12.23.37.png
You do not have the required permissions to view the files attached to this post.

ixtern
Common Wiggler
Posts: 213
Joined: Mon Jan 22, 2018 4:34 am

Re: Erica Synths DIY Bassline

Post by ixtern » Sat Jun 13, 2020 8:17 am

DIY Bassline is not produced anymore and is offered on sale only. I had bought 3 pcb/panel/ICs sets for a steal price, but sadly all of pcbs was 2nd quality - many soldering holes partially flooded with solder.
BTW. It has not stable VCO design and useless envelopes for VCA and VCF. Needs more rework that it's worth.

BarneyRubble
Learning to Wiggle
Posts: 29
Joined: Sun Jul 31, 2016 11:32 am
Location: Scotland

Re: Erica Synths DIY Bassline

Post by BarneyRubble » Sat Jun 13, 2020 8:23 am

ixtern wrote:
Sat Jun 13, 2020 8:17 am
DIY Bassline is not produced anymore and is offered on sale only. I had bought 3 pcb/panel/ICs sets for a steal price, but sadly all of pcbs was 2nd quality - many soldering holes partially flooded with solder.
BTW. It has not stable VCO design and useless envelopes for VCA and VCF. Needs more rework that it's worth.
Interesting I bought both full DIY kits from Thonk very recently. Boards + ICs partial kits can be bought from Ericsynths - no mention of it being discontinued.

qidev.rich@gmail.com
1-Post Wiggler
Posts: 1
Joined: Fri Jun 26, 2020 9:31 am

Re: Erica Synths DIY Bassline

Post by qidev.rich@gmail.com » Fri Jun 26, 2020 11:25 am

scottdanesi wrote:
Fri Feb 07, 2020 9:47 pm
Hey Everyone!

Just got my Bassline all assembled. I am having an issue though as I am getting no sound out of the module at all. The LEDs are doing what they are supposed to though when opening and closing the VCA. I even sent it a gate just to see if it would react to that and it does seem to flash the LEDs properly, just no sound or voltage out. I also checked the output with an oscilloscope, and nothing. Any ideas what I should check? Thank you!
--Scott
Hi, I'm having the same problem. did you ever get it resolved? The module is responding to gate signals as I can hear the gate opening/closing and the LEDs are flashing in time, and I can get the filter to self-oscillate, but nothing from the AS3340 - no signal on any of the wave output pins.

I've checked continuity across anything I can, and voltages where I can - I can't find any obvious shorts. I've checked every solder joint for cold joints, nothing.

Any help at all much appreciated.

Thanks

Post Reply

Return to “Music Tech DIY”