Can I replace a 24uF capacitor with 22uF?


I am planning on replacing the Bennic caps on my Tannoy Turnberry SE low frequency crossovers with either Mundorf Supreme or ClarityCap MR, depending on how many caps I need to buy. Currently there are two 12uF caps in parallel. Can I just replace these with one 22uF cap without hearing any significant shift in frequency balance?
eugene81
Probably - question why would you want to ?

Good listening

Peter
24uf of Clarity MR is quite expensive. I'd suggest using a 20uf Clarity ESA 630v and parallel a 4uf Clarity MR for the final value. That'll give you 95% of the benefit of using the MR for full value.
Can I just replace these with one 22uF cap without hearing any significant shift in frequency balance?
Possibly not "significant" but it depends on the type of xover.
Tannoy usually voice their products very carefully and I would urge you to just replace the caps with the exact same values.
Vapor1, I am intrigued by this idea. Can the 4uF cap really have that much influence even though it is only roughly 16% of the total capacitance?
Clarity can make whatever value you need, they are very very good caps.
The Clarity MR are large caps btw.. I would be inclined to parallel 2x12uf, as the circuit was designed with that esr in mind i would have thought.
Vapor1, I am intrigued by this idea. Can the 4uF cap really have that much influence even though it is only roughly 16% of the total capacitance?

Yes, with some caveats. The Clarity ESA and MR are very similar in character, so this approach works well. If for instance you put a 4uf MR on top of a 20uf oil/paper cap, the results would be more unpredictable. I have used combination of Clarity ESA and Jensen copper foil/oil caps for the smaller value and it worked well, the Jensen character is most prevalent in that case.

For large values like this my go-to is ESA for the big part and whatever flavor on top of them. Since the ESA's are very neutral it's proven to be a solid approach.

Pretty much whatever you do though is going to be better than the Bennic electrolytics.
You can make electrolytics work but they have to be biased correctly! I don't know why, but for some reason most speaker manufacturers don't do this. The problem is that electrolytics can't be reverse-biased. This is supposed to be why you use non-polars. But non-polar caps are merely two electrolytics assembled back-to-back. The problem is not solved- now you have distortion of the waveform in both directions!

The solution is simple. Get two caps of the right value (in this case 47uf). Put them back to back but keep the connection where they meet available. Attach a 100Kohm resistor to that connection, and connect a couple of 9V batteries in series to that resistor and the minus connection of the speaker. If the back to back connection is the negative side of each cap, attach the negative side of your battery power supply to that as well.

What you will find is that the distortion associated with electrolytics is gone! You will also find that they can keep up with expensive film caps for an embarrassingly low price :)

The batteries will last for their shelf life. You could of course replace them with a small power supply. As long as the caps are biased at a voltage greater than that of the incoming signal, its all good.
I've decided to go with 22uF Mundorf M-Cap Supreme + 2.2uF ClarityCap MR. Also replacing 100uF/100V Elytone non-polar electrolytics with 100uF/250V Mundorf MKP + 0.01uF Vishay MKP-1837 -- that should work, right? Thanks!
Atma, your post is most interesting to me. First I have heard of this idea. Thanks.

Eugene, if that large 100 uf cap is for the bass and I am sure it is, then do this. Use 4-6 smaller value Mundorf mkp's in parallel to reach your 100 uf value. This will indeed provide better bass.
Also, use Clarity SA caps instead ........ I just did this replacing the same large value Mundorf with great results.
ClarityCap can wind 630V or 250V ESA to any custom value <200uf or do new compact 400V MR range to 35uf.

ClarityCap North America Sales
Grannyring, which Mundorf caps did you replace, and what do you like better about the Clarity SA? I don't think I have the space to replace a 100uF electrolytic with 3+ large value film caps. But I do see that ClarityCap makes a 100uF/250V ESA so I will go with that instead of the Mundorf MKP and maybe add an MR or even V-Cap CuTF bypass later. I think I will stick with Mundorf Supreme for the 22uF.
I replaced the white MKP Mundorf electrolytics. Bass was improved because it sounds better with the Clarity SA caps and replacing one large 100uf cap with several smaller ones in parallel provides for better sound. I would not bypass at all on this. Just use all SA caps to total 100uf if you have the room.
Grannyring, you should give it a shot.

Electrolytics got a bad name because so many designers don't know how to use them. If they are set up properly they can rival film caps quite easily. If not- then they suck.