Film Caps - Burn-in

[Lostcause]

Hi guy's a quick question....
What's the quickest way to burn these things in?
I've heard of people plugging them in to the mains!?
How would you do that?

The one's I'm looking at are these:
Obbs

Cheers

Lee

[AndrewT]

Hi,
you should not need to "burn them in".

Caps should work straight out the box.

Electrolytics may be an exception if the leakage has gone up during storage and they need a little time, at VERY low current, to re-establish the oxide film.

Plugging them into the mains!! Give me some notice and I'll make sure I'm not passing by in the car.

[peranders]

Lostcause, you can burn in everything according to rumours but when you can come up with a good explanation why you should do it I'll believe you. Eventually all parts will get burned-in, only if you'll wait. You won't have to do anything, just sit down and enjoy.

As Andrew says, electrolytics may be the target for such things but normally leakage isn't very often important, that important so it needs special treatment.

[Lostcause]

Hi Guy's, thanks for the replies but I must admit that after trying several caps there does seem to be a burn-in period.

Electrolitics seem to be the worst case as you said, but I have first hand experience of these film caps changing as they age.

I've been fiddling around with all sorts on my system, cables, caps and speaker position but the one thing that puzzled me was when the same caps seemed to develop more base as they got more hours on them!?...nothing else changed.

The thing is, I'm really listening out for the base extension as I try and remove the BSC of my MLTL's.

They do change...I can vouch for that.

The "plugging-in" comment was meant to stir up the debate but there seems to be little interest....never mind.

Is it 'Snake-oil' or not?

[lndm]

My system sounds a little different every time I listen to it. I suspect my ears are a little sensitive to how I feel, the weather etc.

When I fit new components, I feel I need to trust my first impressions as after a while I think I grow accustomed to them, warts and all.

[mazurek]

Are you sure your woofers weren't breaking in, woofers parameters can slightly change after some hours of use.

[Lostcause]

Originally posted by mazurek
Are you sure your woofers weren't breaking in, woofers parameters can slightly change after some hours of use.

No woofers...just fullrangers.
That's the thing, I'm trying to do without a BSC circuit and therefore listening to the base response in particular.

[Bobken]

Hi Lee,

I was reluctant to comment earlier, because this topic has unfortunately caused some ill-feeling on this Forum before.

However, I have been diligently 'listening' to these effects since I first noticed them over 30 yrs. ago. In my experience, all caps will change 'sonically' to some degree or other when used from new.
Whether some people listening to certain equipment can or do hear these changes or not is another matter, though, and it would appear that a lot of listeners don't.

Some of the most obvious caps to display this effect are Black Gate electrolytics which can still change for up to several months in use. Film caps are just the same, and for example, Rel-Cap who make caps for all applications including military, aerospace, nuclear, telecoms, etc., say in their catalogue for 'film-construction' type of audio caps "Please allow 48 hours break-in before judging sonic performance."

Personally, I have not made much effort to speed up any such break-in process, but simply allow them to change in due course, used in the circuits which they are located in.

In my experience, what happens is that the higher frequencies smooth out with time, and become less aggressive and prominent, and this gives rise to the subjectively increased bass which you have noticed.

In other words, the earlier HF 'prominence' is slightly lessened compared with the lower frequencies, so the lower frequencies appear stronger in comparison.

Regards,

[Jules]

I'm with Bobken on this one, to my ears there isn't much that doesn't sound better after some running in.
I've just replaced the power supply caps in my dac with Rubycon zlh and these sounded awful for the first day or so, all midband , no bass, not much hf either, after a couple of weeks, they're getting there, slight edginess to upper mids all that's left to grumble about.
I've also used teflon V-caps in my stereo 20 and they take a good while to run in 200-400 hrs seems the consensus.
Recently I've been tweaking a Pioneer pds904 for use as a transport (thanks Mikael) using Audiocom superclock 2 and Invensys regs, these also improve greatly over a week or so
Jules

[Lostcause]

Thanks guys, hmmmmm maybe there is something in this after all and it's not just me.
Good point on the calming down of the mf>hf Bobken, hadn't thought of it that way.