capacitor question?

[the_doc735]

I think the only way to fit bigger caps would be to use long leadouts and sit the big caps on top of the other components?
Would that be a bad idea?


Jensen-Paper-Tube.jpg

[the_doc735]

is there any reason why I can't chassis mount large caps in brackets, like the attached example picture?

P1070252a.jpg

[RothwellAudio]

Capacitors - and any other component - should be held in place securely. Having big/heavy capacitors in brackets is a lot better than having them just shoved in somewhere and hoping for the best, but I wouldn't be particularly happy about having them located remotely from their place in the circuit and then long leads making the connections. I don't like the idea of the large loop area and the possibility of instability arising from inductive coupling or some other mysterious mechanism.
What is it you're trying to achieve?
BTW, are you aware of Cyril Bateman's research on capacitors?

[the_doc735]

Capacitors - and any other component - should be held in place securely. Having big/heavy capacitors in brackets is a lot better than having them just shoved in somewhere and hoping for the best, but I wouldn't be particularly happy about having them located remotely from their place in the circuit and then long leads making the connections. I don't like the idea of the large loop area and the possibility of instability arising from inductive coupling or some other mysterious mechanism.
What is it you're trying to achieve?
BTW, are you aware of Cyril Bateman's research on capacitors?

thanx for the advice. What is it I'm trying to achieve? ...someone has put very cheap Monacor caps in the Cary 100t DAC (a dollar each! $) and I want to replace them with high quality caps because 'the cary' is a quality piece of kit; the only trouble is, all the quality caps seem massive and double the size of what is in there at the moment! The monacors are: Ø 17 mm x L 31 mm. Previous to this someone else had fitted Dynamicaps that were: Ø 25 mm x L 39 mm, but I'm uncertain how these fitted in the available space? It seems it may have been originally supplied with OEM/trade Panasonc caps that were replaced with some kind of ModWright caps (early on!)?

I have found these 'budget' caps that would fit the space allocated:


JEL-075 - 4.7uF 100V Jensen Axial Electrolytic Capacitor
https://www.hificollective.co.uk/cat...or-p-9208.html


001-0431: 3.9uF 400Vdc Jantzen Standard Z-Cap
https://www.hificollective.co.uk/cat...ard-z-cap.html


(MKP-060) - 3.9uF 250V Mundorf MCap MKP Capacitor
https://www.hificollective.co.uk/cat...or-p-8503.html


(KPQS/3.9/250) - AUDYN CAP MKP QS 3.90 MF / 400 VDC / 250 VAC 5% AXIAL capacitor
https://www.intertechnik.com/Shop/Cr...,en,7476,46758

...indeed there doesn't seem to be any high end quality caps that are small enough to fit in that space! Non of these are reviewed as being anything other than 'ordinary' (not extraordinary!). Do you know of any small very high quality caps?

Dan wemmer of 'CARY' said:
"sure! ...any of these should be OK as long as they fit the allocated space, there's no real voltage issue there (20 volts max.) that needs that high a voltage cap to be installed, it's just what those caps come as in manufacture, 100volt caps would easily suffice the purpose in this case!"

So that's it: I would like to fit very high quality caps.

[RothwellAudio]

Higher voltage caps will usually be bigger than lower voltage ones. A 400V cap where only 20V is required is bound to take up more space than a 20V cap.
Polypropylene caps are probably best, or polystyrene. Polystyrene only come in small values, so they won't be much use. That means looking for polypropylenes at a high enough voltage for the job.
You could use these:
https://www.rapidonline.com/jb-capac...acitor-08-1312
but they're higher voltage than you need and may still be too big.
This is the full range with size info:
https://www.rapidonline.com/pdf/552455_v1.pdf

An alternative approach would be to use smaller caps of a lower voltage and parallel up enough to give you the capacitance you require.
A third option would be use an electrolytic. This would horrify most audiophiles, but the trick is to use a lot more capacitance than you think you need - and I mean a lot. Instead of 4.7uF use more like 470uF, or more if the cap will fit in the space. Also, use a non-polarised (or maybe called a bipolar) electrolytic if you can find one.

[Firebottle]

+1 for the JB capacitors for good performance at the price.

For a quality capacitor try Mundorf ZN, such as https://www.hificollective.co.uk/cat...or-p-1144.html

The size chart is here, though may be too big still :https://hfc-fs.s3-eu-west-1.amazonaw...11_zn_ps_0.pdf

[the_doc735]

Capacitors - and any other component - should be held in place securely. Having big/heavy capacitors in brackets is a lot better than having them just shoved in somewhere and hoping for the best, but I wouldn't be particularly happy about having them located remotely from their place in the circuit and then long leads making the connections. I don't like the idea of the large loop area and the possibility of instability arising from inductive coupling or some other mysterious mechanism.
What is it you're trying to achieve?
BTW, are you aware of Cyril Bateman's research on capacitors?

I hear what you all say! i.e. 'loops', noise etc.

So, how about a bracket running above the output board? Roughly 20-25mm above the existing circuit board; then 'perch' the bigger caps on top of the bracket (bar) over the original cap locations on the output board?

This could conceivably mean that the flying leads WOULD NOT NEED TO BE EXTENDED, they may be long enough in stock form to reach the output board without any extensions at all!! In addition, the flying leads could also be INSULATED/shielded from EMI/RFI!

see illustration: please forgive inadequate photo editing - LOL!

P1070252B.jpgBRACKET.jpg

[the_doc735]

An alternative approach would be to use smaller caps of a lower voltage and parallel up enough to give you the capacitance you require.
A third option would be use an electrolytic. This would horrify most audiophiles, but the trick is to use a lot more capacitance than you think you need - and I mean a lot. Instead of 4.7uF use more like 470uF, or more if the cap will fit in the space.

so this is wrong then:

https://www.hificollective.co.uk/cat...or-p-9208.html

[the_doc735]

+1 for the JB capacitors for good performance at the price.

For a quality capacitor try Mundorf ZN, such as https://www.hificollective.co.uk/cat...or-p-1144.html

The size chart is here, though may be too big still :https://hfc-fs.s3-eu-west-1.amazonaw...11_zn_ps_0.pdf

many thanks for your suggestions which I shall certainly consider

[the_doc735]

Just to make things a bit clearer:

1) I bought a secondhand Cary 100t DAC
2) Someone had downgraded the Output Buffer Caps. (monacor)
3) Cary told me to return the DAC to original spec OR ABOVE!
4) I decided to upgrade to a higher level than original spec.
5) I would like cap. suggestions from A.O.S. members?
6) Cary said I should keep the Uf to around 4.
7) Cary said the voltage should be above 20, 100 being ample.
8) the current cap size is: Ø 17 mm x L 31 mm.
9) A past cap fitment had been as large as: Ø 25 mm x L 39 mm (very tight).