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04-06-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 21
Post ID: 7132
Reply to: 5129
Something I should have done early on
It took me a while to figure out an effective grounding scheme for the system, and it has taken me until today to finally get around to lifting the K&K's chassis ground at the wall.

The unit is still grounded to the whole system dedicated ground rod via the lug onthe back of the unit, and the "neutral" is - of course - the mains neutral/ground.

Configured this way there is no hum at all now, just a little tube rush at an absurd vollume level.

Noise in general is reduced and clarity and bass are improved, with no penalty.

I have for some time had all the materials to make another of my "usual" cords, which have all 3 wires wired to the wall, but the ground wire does not connect to the female IEC jack at the equipment end.  That should be "better" than the way I have it now because right now the ground wire is presently an "antenna" that is connected to the K&K system ground.  I will report again when I finally get around to making the special cord.

Paul S
04-06-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 22
Post ID: 7134
Reply to: 7132
Bass improved? Are you sure?
 Paul S wrote:
Noise in general is reduced and clarity and bass are improved, with no penalty.
Paul, are you sure? I have seen people told it before but I never believe them and it never happen in my experience. The common mode noises rejection changes bass but not the grounding scheme. Better grounding scheme would certainly reduce noise but I NEVER saw grounding to IMPROVE bass.

The caT


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
04-06-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 23
Post ID: 7135
Reply to: 7134
The "Theory" and the Hedge

Yes, the bass was better immediately after making the swap and, being OCD, I swapped again to confirm.

The "Theory" is that 60 Hz and sub-set LF noises are cleared out of the circuit when all hum is banished ,so pre-amp can send better bass music.

The "Hedge" is that AC was generally better than it's been for quite a while today, but there were the usual sudden lapses throughout the session.  So maybe the AC just happened to get worse during the 2X when I had the 3-prong plug in the outlet.

I'm also guessing ML2s appreciate any help with my bass bins, including less LF noise at inputs.

Don't worry, though, I'm not claiming "World Class Bass", anyway.

However, improvement does include more "downward-developing" harmonics for better wieight, which I like and would take even more of.

Nothing earth-shaking, but certainly worth doing.

Best regards,
Paul S

06-15-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 24
Post ID: 7585
Reply to: 7135
Settling in; settling down

As a weekend-only listener, it can take me eons to break in some of my most stubborn components.  In the case of the K&K, things seem to have reached +/- tonic equalibrium.

I may have have mentioned it in passing, but at some point a while back I changed IC, putting shielded Placette cables from the tranny to the K&K, and I put a DIY "twisted pair" of cotton wrapped 26 ga. soild OCC silver from the K&K to the TAP.  I didn't discuss it in this context because I thought I had this stuff aurally sorted out, at least with respect to the K&K.  But, maybe it was more of a factor than I'd thought...

The last few listening sessions have been notable in that I have had a substantial increase in downward-developing harmonics, along with far less in the way of HF noise passing itself off as as upwardly-mobile harmonics and up-tilted balance.  The net effect of this "downward" trend in balance has been that I find myself more and more comfortable listening to music that "should" be loud at previously-for-me absurdly loud volumes, well up into the 90s.  No, this is not really loud, but remember what I'm using for speakers and amps.  The amazing thing here is that with the cleaner, better balanced signal, the music is still MUSIC at these much higher volumes, and (oddly?) the quietest passages and pauses are actually musically enhanced with the increase in volume.

Another great thing is that I have found a lot more life in my "fading" cartridge since I discovered it (and its arm) had mysteriously sprung all loose (see A Cautionary Tale).  I am also pleased to report that although VTA is as audible as ever, it has become less of an "issue", per se since "The Settling", at least when the AC is OK

One great "test" of a cartridge/system is the best recordings of the best operatic tenors.  If you ever socialize with opera singers, you know that it takes very little in the way of wine and encouragement to get them going.  And you also know how astoundingly LOUD they can sing, with the top tenors 1/2 again as loud as the rest.  Anyway, I am pleased indeed to report that my present system tracks Jussi Bjoerling at close to full tilt.

Once again, I do not use the stock 6N1P tubes in my unit, so I cannot say how the stock unit might develop with respect to pitch and/or harmonics, etc.  I am not recommending the 6DJ8s, especially since the good ones are getting so scarce, and it has taken a lot of work to put to good use their typically over-analytical rendering.  I am pleased to say, however, that the MOSFET/JFET "tails" seem to have quieted the usual-for-these-tubes lower treble noise and sonic "implosion" with loud signals, meaning there is none that I can tie to this source.

Paul S

06-15-2008 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 25
Post ID: 7586
Reply to: 7585
Piano vs. operatic test
 Paul S wrote:
One great "test" of a cartridge/system is the best recordings of the best operatic tenors.
Not necessary only tenors – just good operatic singers would do. Some properly arranged and performed operatic moments are incredibly difficult to handle by audio methods. I for instance have one LP recording of the Onegin’s last few munities with older Galina Vishnevskaya and George Otts crashing through the final duet and I have a lot of crossover intelligence of my Macondo/Melquiades built up around the proper accents of that scene. Big and complex choruses are also a VERY difficult to handle by audio methods… I still would not feel that operatic moments are good test for cartridge/arm configuration. The problem in mechanics of cartridge/tonearm I better hear listening piano music…

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
06-15-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 26
Post ID: 7589
Reply to: 7586
Tuning and trouble shooting with "difficult" music

When the AC and the recording are good, the K&K tracks big choruses and piano fortisimos cleanly, as well, the first time in my hi-fi experience I have had a phono stage that can do this. 

The trouble with the really big stuff is that it's often the recording/pressing itself that gets swamped.

I can usually hear the engineers twiddling knobs to compensate.

Before I installed and adapted the ML2s, I had pretty much given up on a wide range of recorded classical music; especially the big stuff.  But even though I am primarily concerned with previously-off-limits classical now, I still don't have nearly the system headroom to do full-tilt orchestra/chorus, cannons, pipe organs, etc.

However, FWIW, my present limits with classical music repro are not imposed by the K&K.

Best regards,
Paul S

06-28-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 27
Post ID: 7683
Reply to: 7589
Err... The "house" cord is better...
Sneaking up on the AC cord for the K&K, I recently added a close approximation of the power cords I made for the ML2s.  These cords use 3X 12 ga. copper magnet wires tightly sleeved with poly tubing and braided, with Onyx pure copper plugs.  I connected all three wires to the 3-prong wall plug, but I left the ground wire disconnected at the component/IEC end.  This way, according to my shaky reasoning, the mains ground wire "draws off" stray EMI/RFI better than it does when this crap is allowed to "ride" the ground wire into the chassis/circuit and then needs to be drawn off by the dedicated chassis ground.

Who knows if I am on the right track in terms of electronics/physics?  All I can say is, it works better this way in terms of sonics, including less noise/more music.  Residual hum was barely audible at "24" with the ground lifted at the wall.  The number is "28" with the ground wire cut at the IEC end.  Is it odd that I have been listening as loud as 24 for the first time, since I installed the first (ground-cut-at-wall) power cord?  I can't even imagine listening at 28...

Paul S
09-12-2008 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 28
Post ID: 8235
Reply to: 7683
Bass, Overload and Tesla's Ghost

This post is the phono-relevant part of info carried over from my recent "better tubes" post in the ML2 thread.

Subsequent listening has established that the electricity during that session was better than I'd thought at the time (dammit!).  Be that as it may, the combination of decent electricity and  better input tubes for the ML2s yielded bass and apparently-unlimited tracking and wide-band power like I've not gotten to date, and frankly I had not thought my system capable of this level of performance.  No noise, no fade and no "quit" from the K&K during any of this.  I mentioned in the ML2 post that harmonics were not fully developed yet, but since I have gotten better in the past it means that the K&K can do it/is not the culprit now.

So, I take this to mean that the K&K is still more than holding its own in my system.  In fact it has helped me to get considerably more from my system by "improving" right along with other impovements, and it has helped the ML2's new input tubes with redeeming my "fading" cartridge.

Now, if the effing power would only stay good...

Paul S

03-08-2009 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 29
Post ID: 9972
Reply to: 8235
Fancy Cardas Caps: Good, to Better, to Worse in 1 Year?
fiogf49gjkf0d
I have reason to suspect that my beloved large Cardas couplers have continued to loose HF past the point I described as "settling".  HF is no longer correct but rather attenuated relative to LF, and clarity has begun to suffer, too.

I will ask K&K's Kevin Carter if he knows more about this problem.  I will also try Cardas...

Remember, these Cardas caps are not oilers, but they are +/- regular, modern film caps, so I admit I did not give a lot of thought to reliability, apart from using them well within spec'd voltage, etc.  Of course, audio signal path use is a special case; but as near as I can tell, Cardas touts these for just this purpose.

I hope Cardas has not already circled the wagons, as manufacturers are wont to do in response to defects.


Paul S
03-08-2009 Post does not mapped to Knowledge Tree
drdna
San Francisco, California
Posts 488
Joined on 10-29-2005

Post #: 30
Post ID: 9974
Reply to: 9972
Need new capacitors?
fiogf49gjkf0d
 Paul S wrote:
I have reason to suspect that my beloved large Cardas couplers have continued to loose HF past the point I described as "settling".
Well, it might just be the electricity, but if you need to replace them, maybe it is time to try the World's Best Capacitors!!!

Adrian

03-08-2009 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 31
Post ID: 9975
Reply to: 9974
I Suppose If I Say I'm Curious,
fiogf49gjkf0d
then everyone here will just read, "gullible".  However I admit to being totally hypnotized by the Duelund spiel, which I find oddly compelling despite no real, "serious" information apart from the sort mystical, quasi-reverential rhetoric that attends Feastrex, Shindo, Audio Note, etc. "literature".

Oh, well...  too bad 4.7 uF only comes as 200V!  Otherwise, I would be obliged to pony up almost $1k... for 2 CAPS!  Hell, that would put a pretty good dent in a PP2000 (which I hope you will say more about soon)!

Meanwhile, I'm putting grease on all my contact points instead of dealing with any of this stuff...

Best regards,
Paul S
03-09-2009 Post does not mapped to Knowledge Tree
drdna
San Francisco, California
Posts 488
Joined on 10-29-2005

Post #: 32
Post ID: 9977
Reply to: 9975
Dueland capacitors
fiogf49gjkf0d
 Paul S wrote:
then everyone here will just read, "gullible". However I admit to being totally hypnotized by the Duelund spiel, which I find oddly compelling despite no real, "serious" information apart from the sort mystical, quasi-reverential rhetoric that attends Feastrex, Shindo, Audio Note, etc. "literature". Oh, well... too bad 4.7 uF only comes as 200V! Otherwise, I would be obliged to pony up almost $1k... for 2 CAPS!
Actually, I believe they can be tailor made to your exact specifications, which at that price they should be. I thought they came as a 630V version also. It is a very intriguing company, because they address many of the issues of mechanical resonance and electromagnetic field asymmetry that I feel are very important to good sound. I view the circuit like a series of channels for water to flow through, and we want the water to flow effortlessly. If you think about the plumbing in any big building, you know the trouble you can run into, even when all the pipes are hooked up "properly." There is more to it that that.

As to the PP2000, more on that later this week.

Adrian
03-09-2009 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 33
Post ID: 9978
Reply to: 9977
Duelund caps: sanity check.
fiogf49gjkf0d

 drdna wrote:
Actually, I believe they can be tailor made to your exact specifications, which at that price they should be.

It is not a thread about cup but I still….

This is always an interesting question to me – where is the threshold between rational and irrational when I think about capacitors.  The expensive caps made to exact specifications sound like rational but there are no expensive caps that need to hit exact specification. The small caps on some cases need to be very exact but slam caps are not expensive. The large and expensive caps do not need to be exact, nether in uF number, nor in leakage, nor in impedance, nor in any other specification. It is not to mention that capacitance almost always is very flexible parameter and precision of value is necessary only in case of caps use for filtration. However, capacitance doe not filter itself but only along with impedance, so it always possible to play with impedance to moderate the required value of capacitors. Therefore I do not mind the caps to be cheaper and only at fixed values.

Now about the threshold between rational and irrational. Duelund makes huge 300uF caps, 25 kilograms with 1 kilometer of metal in each.  I am sure it is insanely expensive but I question if it is justifiable. It is imposable to control tension and properly damp 1 kilometer of foil in those caps. I never heard them of course but I would very much would like to see those 300uF Duelund caps compete with regular commercial grade electrolytic that would be 1000 times smaller and 1000 less expensive.  I have a feeling that Duelund will not be effective, particularly if electrolytic is used with active basing.

Duelund_Caps.jpg

OK, let to look from a different perspective – my favorite perspective – cost bur solution. The 300uF, low voltage Duelund caps probably meant for speakers crossovers. Those values in speakers crossovers are useful only for low-passing of bass (the area where active based electrolytic destroy any competition) . So, what Duelund offers for low-passing of bass? A $2000 capacitor? Does anybody feel that the Duelund’s solution price-wise very much competes with idea of multi-amping? Do anybody understand that using a dedicated amp for bass and a few nF capacitor in amp’s input is order of magnitude more interesting solution then to use a “magic caps”?

Well, I am not against of what Duelund offers but I would call to some sanity in this subject. Their small, up to 5uf caps might be good but why shell they be expensive?

The caT


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
03-11-2009 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 34
Post ID: 9990
Reply to: 9977
Since I Brought It Up
fiogf49gjkf0d
Well, Kevin Carter says he's had no trouble with his own Big Cardas parafeed caps, and his caps have been in service for 3 years.  He did not say anything about anyone else, but he did suggest there are plenty of other likely suspects where HF issues (etc.) are concerned.

We'll see.

Meanwhile, I recently learned that the big Cardas caps use the same 2-in-1, double-value-caps-in-series (as an anti-induction strategy) that the big Mundorf caps use.  I gather that the 2-in-1 Cardas caps are physically inter-leaved, so I now suppose that the "co-mingled di-electric" I mentioned (that Cardas mentions) earlier is not a Teflon/poly composite material but rather it describes one cap made of each  material, rolled to inter-leave and connect to the other in series.

Gee, that's great...  Now, the hair-shirt-ist in me is thinking that a less-complicated cap would "have to be better"...

In other words, my own brain would overload and self-destruct from audio-neuroses if I did not break the feedback loop with regular applications of pure skepticism, cynicism and self-abnigation.

Paul S
04-05-2009 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 35
Post ID: 10162
Reply to: 9990
False Alarm...
fiogf49gjkf0d

"Cap problem"?  Naturally, it was the BEP, again.  @#*&%!!!

This afternoon the electricity was as good as it's ever been, and things sounded even better than I ever planned (ie, almost as good as I could imagine...).

IOW, the Cardas cap is NOT a problem, in and of itself.

IOW, it looks like my "phono problems" will be solved as soon as I figure out the BEP.

Paul S

10-04-2009 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 36
Post ID: 11911
Reply to: 10162
New MOSFETS and New Adjustments
fiogf49gjkf0d
Another K&K user contacted me recently, and he subsequently sent me new MOSFETS to swap with those I had in my unit.  Original MOSFETs were Supertex DN2540.  New MOSFETs are IXSYS 1N100D.

The only reason I swapped these was out of curiosity.  The other guy said it was "magic", and I wanted to hear for myself what that meant.

The swap required that I remove two of the three boards in my older unit, along with the big Cardas caps and one ground wire, in order to get the MOSFETs out and in without doing a lot of colateral damage.  Another thing I had t do was re-trim the 6922 filament current that was raised too high by the MOSFET swap.  I put shrink tubing on a small, plastic-handled screwdriver in order to avoid shorts while working in the crowded space while the K&K was energized.

The other guy said he'd settled on 1.68V for the new value.  I found this value made my own upper midrange too prominent, so I backed it off to 1.6V.  After an hour of listening (with the unit settling down) I dialed it back up to 1.62V, for an increase in sonic "benefits".

Overall, I like the change.  There is greater clarity and better articulation, with no penalties.  There is also a greatly increased sense of "height" in the soundfield, and the entire soundfield is larger.

This is the first time I have messed with any of the operating values in this unit.  In fact, I never really thought about it much until the new MOSFETS arrived.  Now, I am very interested to continue experimenting with this variable.

These changes do not seriously affect the K&K's character, but they are significant.  I will add to this when I have had more time with the altered unit.

Yes, it has occurred to me that the change in operating values might have more to the changes in sound than the new MOSFETS do.

FYI, this is a K&K "approved" change.

Paul S

10-09-2009 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 37
Post ID: 11930
Reply to: 11911
Tubes (etc.) vs Phono Curves
fiogf49gjkf0d

Rooting around for manufacturers' operating curve/info on 6922s I came across a short paper I got years ago from electronics genius Roger A. Modjeski.  In a nutshell, RM talked about internal variables in tubes that affect their electrical characteristics, and hence their sound.  He specifically mentioned the effects of ESR and other electrical paramenters on circuits, along with inevitable EQ shifts resulting from the individual tube's effect on loop gain due to its simple and in-circuit gain characteristics in RIAA circuits.  Cold water in one's face, to say the least.

To think of tubes like this certainly puts a new twist on old observations about new vs NOS tubes, or one brand vs another in a given circuit.  And since no "circuit" is complete until the fat lady sings, this is effectively causing me to re-think my approach to tube selection and use.

I actually prefer to use SS wherever I think I ccan get away with it.  Since I have been unable to get around tubes for certain applications, perhaps I will go back to where I was with the AI M3A, which is to say, open to experimenting with operating points.

Regarding RAM's own "products", it may have been about 1988, or thereabouts, that I "heard" Modjeski's original RM-9 amp and RM-5 phono-preamp.  I bought the amp because it was dead neutral; and I actually passed on the phono-preamp for the same reason...

I put this post in with the K&K because of my previously-stated idea that changing operating points might be the biggest difference between the MOSFETS in that unit, and RAM's ideas seem to build on those thoughts.

Paul S

02-06-2010 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 38
Post ID: 12870
Reply to: 11930
Caps du Jour
fiogf49gjkf0d
Remember the death and "re-birth" (via good electricity) of the big Cardas caps?  Well, it finally got to where things were not made good enough anymore by good electricity, so I went on the hunt again.  This time I settled on Sonicaps from Sonic Craft, namely the 5.1 uF 200V film and foil Gen. I, "bypassed" by .033 uF 450V Platinum (teflon).  Notice I did not go down in value from the Cardas, what with the R in this case being 10.5k Ohms.

To my knowledge, these caps are single-wound, nothing "special" except high-zoot electrical specs, and someone actually did targeted listening listening to them through development.  Right out of the gate, they were quieter than what the big Cardas had become, but withal the new caps obviously needed breaking in, so I hunkered down and endured them for 50 hrs or so before listening seriously.  At this point, my ambience is back, and song lyrics are easier to make out than ever, without "listening in" to hear them, and without vocal "highlighting", other than what the mix provides.

Interlude:
I suppose it's funny that I have never tried the TRT Dynamicaps, since what they say at their website while talking about them is pretty close to exactly what I think about caps, what they do wrong and how they should be made to sound.  Maybe I should have tried the Dymanicaps, but I have heard TRT's other cap models, each of which were preceded by similar spiels, and I was not impressed with them.  Still, I refer readers to the TRT site/Dynamicap spiel, for educational reasons, if nothing else. And, who knows, maybe they are OK.

Meanwhile, Back at the Ranch:
Likewise, I am not impressed with the Sonicaps; but I am pleased, if you know what I mean.  After only 60 -70 hrs, they are pitched considerably better than the Cardas were, apart from a brief period when the Cardas "settled" through to the right spot; but then they kept on going down, as HF went AWOL.  Also, bass with the Sonicaps is already as good as the Cardas ever were.

I admit that I actually like some of the classic "audiophile" stuff, like spatial ambience and extended frequency response, and the Sonicaps are starting to do a nice job with these things.  However, I first have to have adequate tonal variation that comes from saturation, FR harmonics, timbral balance, texture and intent, or I just don't care about the other stuff.  And the Sonicaps are moving in the right direction with these things, too, already plenty more than where the Cardas had slid to before I replaced them.

Being as greedy as I am hopeful, it seems like these caps are good enough now and they seem to be getting better.  I can't say whether they are fairly priced, but I can say I've paid considerably more for what ultimately turned out to be less.

Of course I'll cry like a spoiled child if these go bad, too...

Paul S
02-14-2010 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,104
Joined on 10-12-2006

Post #: 39
Post ID: 12931
Reply to: 12870
Good --- with a Twist
fiogf49gjkf0d
OK, this turns out not to be a no-brainer. These caps are definitely quieter than anything I've used to date.  At times, there is a sense that "something is missing", but then the "missing" frequency pops up loud and clear, apropos the music (as opposed to the "sound effects").  This has actually been disconcerting, and it is causing me to re-think (again) the "detail" I expect from my system, since it appears in this situation that much of the "detail" has been ubiquitous errant noise (A sort of "over saturation") centered around the lower treble. In this case, HF and LF are appropriate, as transients bear out, including the "missing" frequencies, but the "ambient" "HF" "background" (noise) is just not there.  I think this will turn out to be a very good thing, but it is also kind of weird, as the caps continue to break in and as the inevitable bad electricity inevitably confuses the issues.

For some time I have wanted to start a thread (or expand an old thread) on Ambience; but right now it is enough to say that there have been flashes of truly "spectacular" ambience with these caps, where the music comes from the instruments and the "sound field" includes "sound from the instruments" and recorded reverberations (real or added in) but no (or very little) errant noise "in the air" that typically "designates" "ambience".  By this I mean to say that one does not actually "hear" the HF and LF that define the ambience, but one merely "perceives" a sense of "place" that is distinct even from the usual "recorded ambience".  When it's right, it gives the uncanny sense that the sound in the "soundfield" is "real", which can be quite startling, really.

I well remember how confused I felt when I first listened to the ML2s; they are that different.  And so it is with these caps, I think.  I will keep listening and I will update this report as the caps continue to break in and I get a better handle on them.  Right now, I'm thinking I will put some in the ML2s, as well, if I can mtch the voltages.

Paul S
02-19-2010 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,486
Joined on 05-28-2004

Post #: 40
Post ID: 12977
Reply to: 9978
Twogoodears on the Duelund caps.
fiogf49gjkf0d

Here is the link, though I have no idea whose words he is quoting:

http://twogoodears.blogspot.com/2010/02/again-about-duelunds-coherent-audio-pio.html

The caps are $1000 per 630V/1uF. So, I wonder what those super expensive caps might be used. The 630V suggest it to be used in powers supply. However 1uF in nothing in PS. I know that there are many fools out there who make 300B/2A3/45/10 amps with 4-8uF B+ filtration but those amps sound like shit and “better” caps would not help to them.

To use Duelund in speaker level crossovers would , make more sense but it needed 100V AC in there and the huge 630V would  be hardly usable, not to mention that 100V cap would be 3 times less expensive.

The use of the Duelund in line-level filtration would make more sense. However at the line-level 630V hardly needed and RL filter would kill any, even the best C filter.

So, the only use of Duelund I see for bypass of PS. If so then why people talk about good sound of Duelund but do not mention what were the main filtering cap? The bypass kike only at HF, so commenting about the Duelund sound I think people need to inform at what frequency the Duelund cap is kick in.

The Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
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