RIY: Recapping an Art Pro VLA 1

[AcdNrg]

So I decided to extend from DIY of Eurorack modules to 19" dynamics and my first project is not a complete build, but a repair. I bought a used Art Pro VLA (version 1), right meter not working and "sometimes loosing compression". I decided to give it a shot. As expected, I found leakage on many capacitors that partly spread out to the PCB itself. So I need to clean that up and recap the box. I think it´s a good start beforing spending real money on a bigger SSL clone DIY project. But since this is a first time for that kind of job:

- What are good replacement brands when recapping? I know it´s an el cheapo comp, so it doesn´t have to be exotic high end, but something solid. If the new caps are a tad bit better than originals, I don´t object. Which brands/series can you recommend?

- Take too many photos from too many angles, also noting down the old capacitor values for redundancy. Documentation, documentation.

- I doubt that ART has/will hand out a service manual or diagrams. Are there any other materials covering the VLA1?

- Given the age of the box it´s likely not ROHS, so I´ll pick my old Weller with the corresponding tips + selfmade fume extractor.

That´s my list so far, if you can add something or have worked on an VLA1 yourself, I´d be more than happy to learn from your experience.


Best regards,
Oli

 

[Script]

Try these links:

https://groupdiy.com/attachments/art_pro_vla-pdf.11813/
https://groupdiy.com/attachments/212schem-b-pdf.11836/
I worked on / modded one a long time ago using info from this forum, among other sources. Try search function.

 

[AcdNrg]

Modding you say? Please elaborate

 

[Script]

Modding you say? Please elaborate

OK, search function is on top right of page. Just kidding I'd have to dig very deep in the archives (memory).

Before any mod, need to get it running first. How bad is the cap leakage ?

Looking at the schematic, I am sure I swapped all 10uf elcos in signal path to something higher, like 22uf, for lower filter cutoff frequency. Not sure though what maker I used (some 'audio' grade like Panasonic FC or Nichicon -- if you do want to spend money.)

Also I most likely used better caps in PSU section, very likely low ESR Nichicon over here rated at higher voltage and for 105C (not 85C). 4007 diodes maybe.

Keep us updated how it goes.

 

[AcdNrg]

Just desoldered the bad ones (and their neighbours) , here are some impressions:

after scrubbing with isopropanol


before


there is one tricky spot



but overall I think it will work out.

 

[AcdNrg]

Oh, and search function: I had no idea there actually were threads on the topic. Silly me. Will go through these right now. Thanks for pointing that out. I just didn´t expect to find any and didn´t try.

 

[Script]

Looking good. All power caps should go.

I'd cut some of the glue near 'Lamp' and 'R64' off to make sure you don't have dreck remaining under the glue sitting on that trace.

 

[AcdNrg]

Makes sense. Now where did I put that scalpel

Still reading the other threads and thinking: Now that I got the box open and disassembeld, why not do all in one go. All the other caps, ok, not a big thing. The other I can´t really judge yet, but this will change in the next days. I have a bunch of 1% metal film resistors lying around anyway and started compiling a mouser BOM for the caps already. Let´s see what I do and what I skip.

Many thanks for your support!

 

[Ike Zimbel]

Just desoldered the bad ones (and their neighbours) , here are some impressions:

after scrubbing with isopropanol
View attachment 95264

before
View attachment 95265

there is one tricky spot
View attachment 95266
View attachment 95267

but overall I think it will work out.

The good news is that stuff is glue and not leaked electrolyte from the caps. The glue is mostly harmless (but good to remove as it can occasionally become conductive).

 

[AcdNrg]

Agree on the glue, with tricky I meant that tiny spot where the trace shows (the trace closest to where the cap was sitting. Knocking on wood it´s still conductive, but I will test tomorrow.

 

[tommia]

Glue can be a problem. A known one is in the spx 90.
Good brands are panasonic, nichicon, vishay.
Before you recap first measure, if powersupply is ok leave it.
Follow the signal path and see where the problem is.
Then you learn something and it will be cheaper. One meter not working has nothing to so with rhe powersupply.
Measure the voltage over the meter. Try to swap the meters and see what happens. ...

 

[scott2000]

Now that I got the box open and disassembeld, why not do all in one go.

Because you may not care to be faced with the possibility of making jumpers would be one reason. Could affect any future resale even if most here probably know the little noodle pieces are cool.

 

[AcdNrg]

I´m a hoarder so selling is not an option . But it´s a good thing to consider!

 

[craigmorris74]

While you’re in there, you can also try swapping the stock vactrol for a VTL5C1. These are faster than stock and made the attack and release much more usable for me. I ended up changing both channels in mine.