Question: What to know before recapping

[lo.fi.love]

Hello folks!

I recently became the new owner of a 1992-era Soundcraft Spirit Studio console. I'll probably hold onto it for a long time, I got it for a bargain and it's great for what it is.

In shipping, though, it was dropped on its side and it suffered damage to the chassis. The electronics are fine but I need to take out all the boards so I can repair the sheet metal. Since I have to remove all the electronics, I started thinking about whether I should recap anything.

I'm very handy at repairing analog electronics and I have a comprehensive toolkit including a Fluke multimeter. I can also read schematics. But I'm wondering, what precautions / steps should one consider before deciding to recap a mixer?

For example, I've heard many people say it's best to recap the PSU and then see how much that improves audio quality. And if you want go further from there, to recap the master section, and then the individual channel strips, each time stopping to see what's changed or improved. But I'm wondering what else there may be, any general rules of thumb or considerations to think about.

Any input is appreciated! Thanks!!

 

[The Ghost of FM]

I will offer the following time honored adage: don't fix it if it ain't broke.

A mixer made in 1992 is probably not at the point where recapping is nesasary as Soundcraft made some pretty robust products back in the day and for the most part, still do.

Perhaps if you've come across model specific DIY threads that claim a design flaw and specific recap to fix that issue, I would only then say to go ahead with that and make sure you're using components that are at least as good as what your replacing if not superior to actually realize a true improvement versus the possible placebo effect of doing 60 hours of bench work and telling yourself it sounds better regardless of the reality.

Cheers!

 

[mdainsd]

Your approach seems about right. One thing you did not mention is your de-soldering tools and skills. They will be tested, LOL.
I think people start in the P/S as in here a replacement of dead or dying capacitors will make a global improvement in the board. A scope in the P/S will give you a good idea of whats up with the caps. The master section is a good follow up as you state.

Since you can read schematics, once you get to the strips concentrate on electrolytic capacitors in the signal path. Depending on the number of strips in your board the electrolytic capacitor count can get really big! As in the thousands!

I find it oddly relaxing, going through something like this. Im just finishing up re-capping my stack of 1960's Mcintosh equipment.

 

[lo.fi.love]

Thanks for the input! I'm inclined to leave it alone. I was wondering if there'd be any reason to just go ahead with a recapping job - I haven't even had time to set it up properly and run signals through it. Plus I have a masochistic fascination with long, boring DIY electronics projects

 

[lo.fi.love]

Your approach seems about right. One thing you did not mention is your de-soldering tools and skills. They will be tested, LOL.

(...)
I find it oddly relaxing, going through something like this. Im just finishing up re-capping my stack of 1960's Mcintosh equipment.

Oh, sure, I have desoldering tools, etc. I've done smaller recapping jobs before, just not a 24 channel mixer. And I enjoy this kind of project too, recapping and making snakes are oddly meditative.

 

[altruistica]

Hey lo-fi,

The Spirit Studio desks are so cheap in the UK at the moment, you'd be hard pressed to give one away.
I wouldn't bother re-capping any channels.....I'd just look out for a donor machine as swopping out the boards is really easy to do.

Al

 

[miroslav]

Hey lo-fi,

The Spirit Studio desks are so cheap in the UK at the moment, you'd be hard pressed to give one away.
I wouldn't bother re-capping any channels.....I'd just look out for a donor machine as swopping out the boards is really easy to do.

Al

Yeah....I would say the same thing.
If you are going to take the time, effort and cost to recap a console, save it for a console that is worth it, and that will actually benefit from it.
I'm at the same point with my 25-year old TASCAM M-3500. I thought about recapping a few times, but then came to the conclusion that there would be nothing much gained from it.

As long as you are not hearing any issues....just use it for what it is, and when it kicks, move on.

 

[Muckelroy]

As Ghost said, if it ain't broke, don't fix it. I'd add that if it is broke, you most likely only need to replace electrolytic capacitors. Ceramic, poly, mica, tantalum, and other types of caps almost never need to be replaced and basically last forever. Until they don't. Defective caps of all varieties do exist, but they are much less likely to fail than electrolytics.