Help please ref Fostex FE (83, 88 or 103) SOL Break in period.

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Hello everyone.

I’m just about to start my first two OB builds this weekend (hurrah), and am hoping for some help on a couple of what should be quick and easy questions for you guys. Your advice would be much appreciated / and allow me to get a flying start!

I’ve bought some FE-88 SOLS to go with some JBL drivers (following an OB build already available on line).

Please has anyone any information as to if and how long the 88-SOLS may need for breaking in?
Or if no one has any info on these, how long did your 83-SOLS or 103-SOLS take to break in?

... and if they need breaking in, has anyone got a good solution / thread to follow to explain this?

Many thanks

PS. I’ll do the two questions in separate posts, as they are quite specific and different to each other.
No fixed answer.

a/ Very few people here will have them (they being limited edition units)

b/ While most accept that suspension etc. components require a short time to loosen up, not everyone accepts extended break-in periods exist. The truth as ever lies somewhere in between. And

c/ This varies from driver to driver depending on use, drive level, crossover frequency, slope &c. as relevant. Since, as potential issues go, it is unlikely to cause grown men to swoon, women to tear their hair and urchins to weep in the streets, it's a case of play it by ear. ;)
Basically no. ;) They'll run in, but they'll do it in their own time. You can speed it up a bit, but generally speaking, not a good idea. Think of it like a new car engine: you can hammer it straight out of the showroom, but even modern ones repay a bit of mechanical sympathy. Most of it is the moving components (suspension, especially the spider) but wideband cone units employ flex / resonance of the cone itself, and it will alter a little with some running time also. Not night & day usually, but often some, and it's typically this that takes longer.
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Curious how your build with FE83-Sol OB is going? I have a pair that keeps getting better after 200 hours now in a front ported box. Really shine mated to pair of bucket subs driven by Crown XLS amp. Took awhile to find the right combination to tame down the shouting/brightness. Now that I got my feet wet (sort of speak) with full range, I'm eager to try another bookshelf build that's significantly better.
Hi and many thanks, good to know.

The SOL build is going slow. Mainly because I was working on a J.E. Labs / Supravox 8" Bacon build first as it should have been quick and easy, give me something to listen to whilst doing the Fostex / JBL build and getting my head around crossovers.

Unfortunately, i've just fond out one of the Supravox drivers is damaged, so contemplating a DIY repair!

In the meantime, fostex cutouts done yesterday and not started breaking them in yet, so very early days (Pre / Power amp away being recapped).

Still early days, but will report back ...
I'm in the hammer camp. Mount them cone to cone, wire out of phase and drive close to Xmax with a sine wave at Fs over night. An hour at 1k and another hour at 5k with about 1W of power and done.
I think he's simply asking where you obtained yours, which doesn't seem an unreasonable question.

I would be very wary about beating seven shades of Shinola out of delicate 3in wideband drivers, especially with a signal of limited variation. You can hammer a woofer in that way to loosen its suspension, but freeing up the suspension components usually only takes minutes -a few hours at the most. However, wideband drivers produce most of their BW through resonant & bending action of the cone rather than piston behaviour, and constantly feeding them high levels signals with limited variation can end up overstressing one area while leaving others less affected. See what I typed on 2 February.

In all honesty, you don't need to make meal out of this subject: there really isn't much to say about it, it's just basic mechanical engineering.
Thanks Scott.

I searched for mine on ebay and bought them from a dealer called:
Good price, great reviews and arrived no problem at all.
That was / is for the Fe88-SOL's. Not sure if he has other models.

Thanks for the comments Scott ref burn in.
Now have the info I need to know :)
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