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Well, we have the final talley.Over the last several days, I have clip-lead orientated TEN cap positions in my two stage DC stereo SET 45 amp, six power supply film cap positions and four Rk Bypass film cap positions. I listened very intently, and triple checked it all.
Out of 10 positions in this stereo amp, the film caps were wired OUT of optimal 180 degree orientation, in 8 positions!! 80% were " backwards".
That is quite a number. Imagine what happens when you install backwards the Rk film bypass cap of BOTH of the amp's main ( only ) mu of 100 driver tubes !! BOTH of mine were originally installed backwards.
I need a day of so to finalize-solder inplace the last-tested caps, and give a listen and report..
As of last night, with 9 of the 10 film cap positions optimized, the amp played "clearer" to me. NEED to properly solder all and give an audition with 10 out of 10 film caps positioned 180 degrees correctly.
How is the amp you are using now film-cap-positioned? You likely don't know, do you ? There is WORK to be done - by all of us !! The fruit of your time and labor will be sweet !! Have fun.
I'll try to take some underside photos when done. I added two DynamiCap 4.0 uF Es to the front end supply, ( LIKE them !!! ) and did additional wire optimizations, also using clip leads to assist me in amounts of wire determinations - between spans, by ear. Cute.
Jeff Medwin
Edits: 08/22/16 08/22/16 08/22/16Follow Ups:
jeff - was the 4uf dynamicap change done at the same time as the cap polarity business?
if yes - wouldn't that possibly color your subjective evaluation?
as well isn't it possible that everything interacts and that as you change the polarity of some capacitors then others might behave differently?
is it possible that now you have arrived with everything in the "correct orientation" that you could repeat the experiment and find that things have changed and that you may need to change the orientation on some capacitors?
in other words - if the 10 uf caps polarity changes is it not possible that the best possible orientation for the .68uf capacitor could have changed - since you don't necessarily use the foil orientation?
maybe they should be done in a certain order - IE large capacitors first?
a lot of variables here to manage - it'd take a genius to do it all in their head.
while jumping the shark - is it not possible that the cap orientation could have an effect on the correct amount of wire to use and vice versa?
Rage, I suggest you go and listen to your amps with components attached by clip leads. I am going to do exactly that; beats cutting grass.
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
for the record douglas, I could not hear the 4uf dynamicap implemented the way Jeff suggests... so I traded them to jeff for some chokes.I'm trying to eliminate caps... and parallel runs of wire.
I want 80% return on 20% effort.. all this polarity, wire leads, bypass caps is too much tweaking for me.. I just want to listen to my stereo and watch movies.
sounds pretty good right now without tweeters if that is any indication of my hearing.
I'm also hooked on L-critical choke input now... I can even rationalize choke input being better based on DFs guidelines... (although he wouldn't agree!)
I just need heyboer to make me a 5H choke at 20 ohms that doesn't weigh a ton.
Edits: 09/02/16
Good luck wid your project, they are quite nice to listen to I bet. You know what the circuit needs ideally. Less resistance/more resistance, or perhaps less capacitance stray to ground or what ever. If there does not look like a reasonable change in any of the desired parameters, and I don't hear any reason to do it except, 'it makes the amp sound ssooooooo much better' I tend to leave things alone. There are also sources I tend to ignore unless I see some underlying benefit to a tweak they 'discover'...as the usual state of affairs with such discoveries is that they don't understand what they have done.
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
Rage,
Everything interacts.
I did the Dynami 4.0 Es next to the last, as the plate supply of the Driver tubes, to more easily hear what is right and wrong on the Driver tube's Rk bypass caps. The Drivers' tubes Rk caps were the only ones evaluated with Dynami Cap 4.0 uF Es in place.
Yes, wire is a BIG thing, and it IS mind boggling to attack, throughout the amp. This morning I was listening to one versus two strands of 14 AWG Mil Spec wire, connecting to the Finals tubes' Rk resistors. I am about to go from clip lead to optimized soldering in, and hear that next ( two 14 AWG instead of the existing one run ). Lotsa work, glad the Pioneer Elite Blu Ray player has a great remote controller.
Jeff
One further comment Rage, ALL of the MANY small bypass caps were ripped out of the amp, and ALL orientating was done with the "larger" main caps ONLY.Yes, it does take a genius to figure this out AND / OR, someone who is average yet simply dedicated, highly motivated, and focused .
Finally, I would guess its repeatable.
Jeff
Edits: 08/26/16 08/26/16
Thank you for sharing your experience.
If you're suspicious of the correlation between the capacitor markings and its "polarity" between each batch, I can suggest you to measure each for the outer foil using an oscilloscope. Later, you can listen to this particular capacitor model how it suits you better sonically - with the inner or the outer foil towards the input.
I believe it's a faster method if you have to manage a large batch of capacitors.
Best regards,
Alexander.
Don't you THINK I have thought of that?? I have. Just because we can measure for the outer foil, that does NOT mean you have answered the question of " What orientation sounds BEST, in any particular circuit !!"So, since I plan to keep this amp, and my VOTTS for personal use, I took the time to listen to each film cap both-ways IN CIRCUIT, and KNOW for SURE.... what is best sounding.
There was a lot more CLARITY to the presentation, listening last night for the FIRST TIME, with all 10 or 12 in place correctly !! I use Brendel playing solo piano, Beethoven Waldstein Sonata, VERY good to A-B, 20 second (or less) snippets. Its amazing how many notes can get played and heard in a SHORT time by a great pianist !! AND, with solo piano, there are MANY things to listen for !!! Once all is aligned - enjoy the whole piece !!
If I were to build duplicate amps, same design ( why of course, what else but a two stage DC SET ?? ) I could disconnect wires connecting caps on THIS amp, and test for outer foil and denote it. That, I may do, but now, I just want to "perfect" this amp for my own use on my ALTECS. Amps, not speakers, are the turkeys, the real weak link in audio.
Thanks for thinking and sharing up here. I would like for you to please send me your email address, so I can send you a document on amp-designing I authored. Thanks.
Jeff Medwin
Edits: 08/23/16 08/23/16 08/23/16
for a 10uF capacitor, it's damned difficult to determine which lead is connected to the outer foil for capacitors of this value, and above, in theory because impedance to typical test frequencies is low, either way. I tried all the well known methods, and I never felt that I got a definitive result that distinguished one orientation from the other. I don't know where the cut-off point might be for getting a reproducible unequivocal result, but it's below 10uF for sure. That said, I did not try very very low frequencies, where Z might be high enough to make a determination, like 20Hz and down.
Hi Lew,Tell me this please : Did you ever try using a scope?
Dennis suggested tonight I do it that way with film caps' outer winding determinations, and not a DMM as Percy suggested.
---------------------------------------------------
Dennis Fraker uses a simple single trace scope for multiple transformer alignment ( Ef XFRS to B+ transformers on AC fed DHT filaments, and one power transformer to another power transformer on his monoblocks ) all the time.
Let me know please.
I keep thinking, in my mind's eye, of how pretty the cam covers used to look on a vintage Alpha engine. Send us a photo please if easy to do. Old times.
Jeff
Edits: 08/23/16
The experience caused me to do some internet surfing, and I did find that I am not crazy. Others have also found that the usual audiophile methods for determining polarity of a film cap do not work so well for high value capacitance. The one qualification I would make as regards my finding is that I am not immersed in this business every day of my life. So when I encounter a new problem in electronics, I often have to re-educate myself with respect to the relevant science that I may have forgotten due to not using it. I cited one example of where I may have erred in not subjecting the capacitor to very low frequencies, where impedance might have enabled me to see a difference. I think I went down to 50Hz with my audio signal generator. I actually short-circuited the problem by deciding to use some 10uF Auricap XOs, which come from the factory with color-coding, denoting the lead connected to the outer foil. That decision was made based on the idea that the Auricaps would sound better than what I had (Cornell-Dubillier), not just because of the lead markings on the former brand.
Now you've got me thinking that it would be interesting to try lower frequencies on the 10uF CDE capacitors, which went back into my stash after I decided not to use them in this application. Just to see if that works.
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