Bare Knuckle Pickups Forum
Forum Ringside => Tech => Topic started by: Dmoney on August 12, 2011, 01:57:15 AM
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Anyone used the 100uf 500V axials made by TAD or JJ?
I see them on tubetown and the TAD website. I usually use F&T's but I kind of want 500V rated caps and I can't find 100uf@500V axial F&T's. The the JJ's or TAD's are better I might use them this time round.
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Ive heard great things about the JJ caps.
Especially the big electrolytics
Why cant you find the F&T? is it still the supply problem or are there just no exact values?
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Anyone used the 100uf 500V axials made by TAD or JJ?
In fact I used both (on different amps) and they work well.
Cheers Stephan
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diezels come with ruby caps, which are probably the same as TAD
I'd take a sprague over them, anyway
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I find the sprague are hard to find and expensive
It seems hard enough to get hold of a range of values in F&T's, JJ, TAD, Evox Rifa... let alone sprague or mallory.
I could nosey at mouser and farnell, but I don't want to pay £15 postage for 4 capacitors.
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I find the sprague are hard to find and expensive
It seems hard enough to get hold of a range of values in F&T's, JJ, TAD, Evox Rifa... let alone sprague or mallory.
I could nosey at mouser and farnell, but I don't want to pay £15 postage for 4 capacitors.
I agree whilst the sprague stuff is great it can be awkward to find.
Have you checked bluebell audio? if i remember correctly they stock a large amount of spraque stuff
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actually scratch that they dont seem to have any caps at all now.
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yeah! no caps. pretty odd.
hoffman appears to be down too but I wouldn't buy from him unless i really had to. Just cos he's in the US.
I'm sure there are better rated caps out there than the sprague and mallory stuff too.
I'm gonna use the TAD i think. The temperature rating on the JJ's is for 70degrees while the TAD is 85 on the 100uf/500V and 105 on the 47uf/500V. For longevity it looks better to use the TAD.
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Hotrox have a few of the sprague etc
but theyre values like
100uf/350v 100uf/385v
good luck with the erm i guess jcm800?
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Never tried the TAD or JJ caps but have heard from people I trust that they didn't fare well when compared against the F&Ts.
You can get 100uF/450v axial F&Ts from Audiocap here in the UK... http://www.audiocap.co.uk/high-voltage-axials-electrolytics-over-300v-ft-17-c.asp
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I'd trust the F&T more.
I know about audiocap.
I'm using a 350-0-350 hammond. I'm going to use a diode rectifier. I've gutted out the GZ34 from my old build in this chassis. is 450V not cutting it close or should I be thinking of a slightly larger margin?
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I'd trust the F&T more.
I know about audiocap.
I'm using a 350-0-350 hammond. I'm going to use a diode rectifier. I've gutted out the GZ34 from my old build in this chassis. is 450V not cutting it close or should I be thinking of a slightly larger margin?
with that PT, I'd say even a single 500v doesn't have much margin in there - I'd be looking at running two caps in series to increase the voltage handling, like these... http://www.audiocap.co.uk/ft-a22135025049-220uf-350v-electrolytic-25x49mm-51-p.asp
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Have you checked out hificollective.co.uk for high end electrical components?
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I think it depends on the amp and context it is in circuitry. But overall F&T are better regarded than JJs or TADs.
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I know they're better regarded. I prefer F&T, the problem is just choice of capacitance and voltage ratings. Getting hold of certain caps just seems like hard work at the moment.
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I prefer F&T over other brands of cap used in valve amps, as they have the best specifications in therms of lifetime.
One feature of electrolytic caps not often discussed is temperature rating.
Your capacitor datasheet will (well should) give a life expectancy at maximum temperature rating and maximum ripple current, with curves to show the effects of running the caps below both these parameters.
For every 10degC you below its rated temperature you run a cap, you double its life. So a 105degC/1000h cap will last four times as long as an 85deg/1000h rated cap).
Most caps are rated at 85deg.
I don't use JJ caps. JJ caps are rated for 1000h at 70degC, which seems on the low side to me. Furthermore their can caps are slightly bigger than the standard 32mm can found in vintage amps, so are harder to retro fit when repairing older amps.
I don't Sprague Atoms. Some Sprague Atoms are only rated at 65degC. Indeed I saw some of these today in an amp. After much badgering I managed to extract a (fairly derisory to say the least) datasheet from Vishay for the Sprague Atoms, and I was not impressed. They are also expensive
Ask Jan First stock most of the F&T range.
http://www.askjanfirst.de/eindex.htm
If you don't mind using radial caps, there is an excellent selection of inexpensive 105degC rated caps up to 450 VDC, eg the Panasonic EE series, rated for 10,000 hours at 105degC
http://uk.farnell.com/panasonic/eeuee2w470/capacitor-47uf-450v-16x31-5mm/dp/1673505