Should I re-cap my 105.3's

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Hi all
I have a pair of 105.3 ,have had them for around 5 years I did the bass driver refoams when I first got them which went well ,
I then got through around 4 sets of tweeters which I think was from driving them with a Denon A1 av multichannel amp (quite loudly).
I now have a pair of bryston 7bsst monoblocs and they sound great (and dont blow tweeters) .
I am toying with the idea of replacing the caps (falcon acoustics now do a kit)
So is it a good idea to replace them all due to age ? I am also thinking if there not broke don't fix!,,
Hmmmm :confused:
 
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I have a pair of 105.2's which I recapped some years ago and it made them much clearer.
I am not sure how familiar you are with electronics and if you do recap the crossover you may feel happier using a ready made kit. However if you do want to DIY you will be able to buy the individual capacitors from Rapid Electronics, Farnell, RS or Wimslow Audio. The latter company specialise in speakers and you will find them knowledgeable of your particular speaker.
I would replace all plastic capacitors ( especially in the mid and treble filters ) with polypropylene ones and replace bipolar electrolytic ones with new bipolar electrolytics.
The spec for the 105.3 does not show any weakness at the low end and I would suspect a piece of equipment earlier in the chain if you lack base.
Don
 
Hi
If you do decide to change some capacitors from electrolytics to plastic then you need to compensate for the reduced equiuvalent resistence of the plastic capacitor as compared to the electrolytic capacitor by adding additional resistors in series with each new plastic cap that replaces an electrolytic. That is why I recomended sticking with electrolytic capacitors where already used.
when I recapped my 105 speakers I spoke to KEF about the possibility of changing from electrolytic to plastic. The reply was that their crossover design did take account of the characteristics of each capacitor used in the crossover. KEF recomended reusing the same type of capacitor and NOT changing from electrolytic to plastic. If a change from electrolytic to plastic is made KEF recomended adding a resistor in series with the replacement plastic capacitor with a value of 1 ohm for each 10uf of electrolytic capacitor replaced. In KEF's view this was as close as a replacement plastic capacitor could get to the original design.
Also I do think that electrolytic capcitors have a worse reputation that is really deserved.
My crossover does contain electrolytics as in the original design except in the treble crossover where I changed to all plastic with added resistence as recomended by KEF.
I hope this explains the rational behind my original comments.
Don
 
Is it the percieved wisdom that i.r.o the bass section of the 105/3, the crossover is "as good as it needs to be ?"

I'm curious.

Some say:- "chokes mst be air cored" but the inductor(s) in the bass section on my 105/3's are the size of a house ! - I think they are ferrite dust cored and look very expensive.

What would be the up / downsides of going "air" ?

Supplementary question:-

Imagine I wanted the bass to reach a few hz deeper, where would you start ? If you are not familiar with the 105/3 crossover, please see piccies below:-

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Thanks
 
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Changing the crossover is not going to give you more bass. LF extension is a function of the drivers and the box. If you want a tad more bass, build a pair of subs.

Air coils may have a tad less distortion, but need more wire, so to the the same resistance, thicker and a lot more money, let along they will be physically very big. I only use air up to 1mH. The caps will be causing far more distortion. Nothing much you can do about that except maybe bypass them with 1u films.
 
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