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Old 21st January 2008, 03:21 AM   #511
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I am using 22R for R3 now, but trial period is far from finished.
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Old 21st January 2008, 03:42 AM   #512
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Quote:
Originally posted by yggdrasil
...trial period is far from finished.

As any self-respecting DIYer knows, off course not.
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Old 21st January 2008, 05:30 AM   #513
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Default "Really"

Yeah Carpenter,

Works like magic, nearly everytime, with very different ccts, too!

- 0.1 ohm (+,-) in series with 0.1uF cap (propylene, or better)as a bipass to any electro for example, is a good starting point.

- simple to try - maybe easier to get low ohm SMD resistors

- try it on your 2246 driver Xover cap.

See also "Capacitor bipass" thread - interesting.
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Old 21st January 2008, 07:24 AM   #514
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Default Re: "Really"

Quote:
Originally posted by jameshillj
Yeah Carpenter,

Works like magic, nearly everytime, with very different ccts, too!

- 0.1 ohm (+,-) in series with 0.1uF cap (propylene, or better)as a bipass to any electro for example, is a good starting point.

- simple to try - maybe easier to get low ohm SMD resistors

- try it on your 2246 driver Xover cap.

See also "Capacitor bipass" thread - interesting.

Thanks for the tip--I'll give it a whirl.
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Old 21st January 2008, 11:28 AM   #515
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A practical adventure of capacitor bipassing -

I'm optomising an F3 amp (Peter Daniel pcbs) and the o/p cap started off as a Rifa 15,000 (C1), Pana FC 220 (C10), plus 4.7uF Solen (C8). Well, the Rifa's are excellent for power caps but lousy for signal - replaced by 4 x 2200 Pans FC (excellent) + 1000 Nicki Gold (Curiosly - maybe slightly heavier sound, maybe b.s. too) C10 became 220 B/Gate (much better everything) and C8 became 4.7uF ICW Clarity cap (better small signal, brighter, etc but a noticable mid/treble smearing).
Adding the series R (0.25R) removed all "smearing" but rolled off some tops, so added another parallel "string of [0.15R + 100nF] styrene (like Rel caps) = incredibly treble increase, and so on, and on, ...

This particular one ended up with both the film caps in parallel [4.7uF//87nF + 0.1R] as a bipass across the group of 5 electros which suits my perception of a reasonable balanced sound, for the present system setup and my no doubt, imperfect hearing.

Unfortunately the p/supply is still growing up and this is causing different bipass adventures, particularly with the smaller values of final p/s cap. That "Carlos" snubber is useful here, too!

- Multibit NOS Dac + D1 O/P stage into X2.5 preamp (original) driving A.A Domestic Monitors - nowhere to hide here!

[The reference is Slee, etc into AKG 701's, 880's and the Stax.]

Ran 15" base + 4 way trax horns awhile ago - big room, too!

Hope this is of some relevance and brightens up your week!

Cheers
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Old 21st January 2008, 04:30 PM   #516
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jh, would you mind posting a drawing? The various combos sound interesting. I want to be certain that I have the correct mental picture.

In gain stage coupling with caps, do you use the same procedure, or is this reserved for output caps only?
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Old 22nd January 2008, 12:27 PM   #517
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Woody (if I may be so bold!)
Will send you an email with scanned attachment later and perhaps you can get it posted here for me - lacking a certain computer "moxy"!

The bipass approach is one solution to some of the shortcomings of electros, particularly good quality ones, for both high & low signal and in power supplies.

In gain stage coupling, I use v. good quality film caps and just parallel different ones "to taste", as it were - easy to sort out - nothing really scientific about it at all, I'm afraid, apart from the usual sig gen, CRO, etc.

I hadn't thought about "R loading coupling filmcaps" for sound, though - thank you - must try this - pretty sure someone has tried this before, yes?

For some people and systems, good electros sound better if you leave them alone, thus "end of story"! No probrem!

For now -
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Old 22nd January 2008, 04:31 PM   #518
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Quote:
Originally posted by jameshillj
Woody (if I may be so bold!)
Will send you an email with scanned attachment later and perhaps you can get it posted here for me...

I'm actually getting to like my nickname, seems fitting--also describes my true talent. If only electronics and engineering came as naturally.

I'll be happy to post your email graphic. It's interesting to learn other techniques.
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Old 23rd January 2008, 09:43 AM   #519
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Did I see somewhere that you have a R.Cuff injury? Sorry to hear about it - had similar (squash injury) and b. painful - took ages to come good even with physio and work.

Cranking up the scanner - page soon.
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Old 23rd January 2008, 04:19 PM   #520
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Quote:
Originally posted by jameshillj
Did I see somewhere that you have a R.Cuff injury? Sorry to hear about it - had similar (squash injury) and b. painful - took ages to come good even with physio and work.

Cranking up the scanner - page soon.

Yeah, that's the problem: Severe R. Cuff strain. MRI makes my shoulder look like a battlefield. Of course, everyone over 50 looks that way, according to the specialist.

Thanks for the scan. No hurry, though...
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