| Franz |
Hi everybody!
I have been following this forum for a while now and I am about to build Aleph 5 Monoblocks for the mid/treble range in a biamped system.
One of my main concerns is about PSU design. I just read Nelson Passīes article about the XA series. It struck me that he uses high speed /soft recovery rectifiers here in contrast to what he says in the older articles about amp psu design, where he favours slow diodes aka standard bridges bypassed by caps.
There must be some sonic benefit otherwise Pass labs wouldnī t spend the extra dollars for those components.
Does anybody have an idea why Mr. Pass changed his mind about this issue?
Anybody ever tried both and did a comparison?
Maybe the Maestro could himself give some comments.
:confused:
Thanks for your replies
Franz |
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| till |
Somewhere, i think in the alephx thread is a statement of Nelson, they use the "fancy diodes" because Wayne wants them. If you search a little bit in the board, you will find also the comment, best choice would be schottky diodes.
And you will find comments, there are much much more important things than which kind of diode, capacitors, resistor you will use. |
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| protos |
| My recent experience in replacing normal diodes for FREDs in my DAC psu was quite positive. I perceived a tighter bass and more dynamics. I haven't tried it yet on the Alephs but I am thinking about it after the Dac mod. I think Nelson has said he doesn't like fast recovery types but I am not sure if that includes soft recovery types. |
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| JDeV |
| quote: | Originally posted by till
Somewhere, i think in the alephx thread is a statement of Nelson, they use the "fancy diodes" because Wayne wants them. If you search a little bit in the board, you will find also the comment, best choice would be schottky diodes.
And you will find comments, there are much much more important things than which kind of diode, capacitors, resistor you will use. |
Here is some more comments and Mr. Pass's comment on Wayne's choice.
http://diyaudio.com/forums/showthre...ne&pagenumber=1 |
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| Klaus |
Hi,
step by step I replaced over the last years diodes in my consumer devices by soft-recovery ones. In DIY projects I used them right from the start on. In all devices the benefits were the same. I think they are not standard due to there higher price.
It is not the most importent thing - without a One and Only design no start could be made - but to achieve 100% performance this tricky tweaking stuff is absolutely necessary. As well as best Caps with bypasses, inductance-free power resistors and so on, and so on. When I e.g. compare my DIY-Aleph with a Pass-production one a clear difference can be heared. My budget for material was allowed to be higher, thatīs the difference. Lucky DIY-guys...
Klaus |
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| JDeV |
Hi Klaus,
Can you specify the data of the diodes you used eg: make, model number - please. |
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| Klaus |
Hi Baz,
I used and tested various Diodes, e g
http://www.schuro.de/Daten/IR/31dq10.pdf
http://www.schuro.de/Daten/IR/hfa08tb60.pdf
http://www.schuro.de/Daten/IR/hfa25pb60.pdf
I think all simular diodes are pretty good. The inner resistance could be helpfull with small value = good damping. But the main thing is to my understanding the much lower reverse switch off charge energy. The best should be the Schottkies, see type 1 - but "just" 3,3A nom current. And this all has nothing to do with "ultra/hyper-FAST"... We rectify 50/60Hz - but with hard class A current peaks.
Whatīs better: to have a Schottky or to reduce inner resistance? I donīt know yet, with my Aleph P in Progress Iīll test and report.
Regards to the Summer-half
Klaus |
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| hifiZen |
Have a peek at MBR3045WT and kin from IR. These are what I used for my prototype Aleph-X. Can't comment yet on how they compare sonically to anything else, but these Shottky's have two nice characteristics:
1. low price (for a high performace diode)
2. very low forward voltage drop (roughly 0.55 to 0.6V), which translates directly to greater efficiency and reduced heatsinking requirements. Quite possibly this also means greater reliability. You'll have a hard time finding another diode type with such a low forward voltage drop. |
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| Circlotron |
| I have never heard of anyone using fets as synchronous rectifiers in a 50 / 60 Hz power supply. They are the ultimate in low forward voltage drop. The idea is to put the current in the reverse direction to normal through the fet, and turn the gate on (positive as normal) when you are doing this. When the voltage is in the "normal" direction (source negative, drain positive) you keep the gate off so the thing doesn't conduct. This makes an almost ideal diode. Watch out though - the body diode of the fet while quite ok for rectifying low frequency ac, can have a very sudden, hard turnoff so it would be quite noisy. When the gate is turned on, any current that would flow through the body diode flows instead through the normal drain to source path. Only if the voltage drop (amps x rds_on) is greater than ~0.6v will current then flow through the body diode as well. |
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| jackinnj |
| this is where it's helpful to have a good oscilloscope -- you can see the problems of some fast diodes -- more of a problem for switchers in which every millimeter of lead length means extra inductance. |
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| wayne |
We have switched to high speed soft recovery diodes for two reasons. They are quieter when used properly (CE EMI TESTING)
and they do sound better.
I ran extensive tests for CE approval with a CISPR 15 network feeding our spectrum analyzer. Diodes generate noise from 120 Hz up to MHz that is very hard to see on a scope but shows up on the spectrum via the AC line. Caps snubbers etc didn't help and often made it worse. |
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| Bobken |
| quote: | Originally posted by wayne
We have switched to high speed soft recovery diodes for two reasons. They are quieter when used properly (CE EMI TESTING)
and they do sound better.
I ran extensive tests for CE approval with a CISPR 15 network feeding our spectrum analyzer. Diodes generate noise from 120 Hz up to MHz that is very hard to see on a scope but shows up on the spectrum via the AC line. Caps snubbers etc didn't help and often made it worse. |
This is my first ever post, so please forgive me if I get anything wrong or offend against any board protocol, or whtaever, with which I am not familiar.
Some eight years ago I carried out many extended listening tests (I had no appropriate test equipment) on all of the diodes I could lay my hands on at that time. I used the diodes in 'discrete' bridge rectifier configurations in several different pieces of audio gear.
To my ears, there were quite obvious differences in the 'sound' of these diodes, and the best I tried were schottkys by a noticeable margin.
Interestingly, I also tried many combinations of snubber caps, using various makes and types of caps of differing values, and came to the conclusion that they all did something to the overall sound which I didn't care for.
Since then, I have used schottkys exclusively in all of my projects and have used them both in parallel and in series to cope with higher currents and voltages (without any balancing resistors) and have not experienced any problems due to unequal power sharing, to this date. Perhaps I have just been lucky with this, but schottky diodes taken from the same batch do appear to be sufficiently well matched in specs to be OK.
Initially, I did 'blow' a couple of somewhat underrated diodes, which puzzled me, but they were being fed into a huge bank of caps which I soon realised would seem almost like a direct short to ground at switch on, so their 'surge' ratings do need to be watched.
I was heartened to see Nelson's earlier recommendation in this thread in favour of schottkys, and in particular, Wayne's remarks in this post about the 'proper' objective tests they have carried out, especially regarding snubbers, which I continually see recommended in DIY articles, but which my ears told me were (universally) not a good move.
I would very much like to know if Wayne's tests showed any possible superiority with schottkys over fast/soft recovery diodes (these were not available when I did my listening tests) which gave rise to Nelson's overall recommendation, and if it is purely on grounds of cost and restricted power handling etc. that Pass Labs don't use schottkys rather than fast/soft diodes in their production.
If anyone else has made some direct comparisons between schottkys and the latest very fast, soft recovery diodes, I would be very grateful for their comments and opinions.
Finally, although I have only just joined the Forum as a member, I have been looking at the board off and on for some months, and I am simply amazed at the generous sharing of information which occurs, and the help shown by the more knowledgeable members to those who are less experienced.
In this day and age, it is simply wonderful to see so many like-minded people, who are not only out to do everyone else down, freely sharing their knowledge and experiences.
Long may it continue, and whilst it was very sad to see some animosity creeping in a while ago in a few areas, hopefully with a slightly more enlightened approach from the current Moderators, the Forum will go from strengtb to strength.
I almost hesitate to mention this in my virgin post (as subjective opinions seem to really excite and agitate some people to an extraordinary extent), but I have spent over 30 years patiently 'listening' to active and passive components in all manner of audio circuits, and during that time I have reached some quite positive conclusions.
I sincerely hope that I will be able to add something worthwhile to the discussions, where appropriate, at some times in the future, out of grattitude for what I have picked up as a guest onlooker during the past few months.
A very Happy New Year to you all. |
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| hifiZen |
Welcome to the forum, Bob!
If your first post is any indication, I know that I and other members will be looking forward to hearing more from you! Controversial or not, opinions are always welcome here, since not everyone has the time and means to do things like head-to-head rectifier comparisons... there are just so many variables in any audio design, one could spend a lifetime doing comparisons of this and that. That's what makes this forum so special - the sharing of information, experiences, and ideas! :up:
As far as the negativity which creeps in every now and then, I've found that simply ignoring it altogether is a great way to deal with it! :) I've not felt offended or invaded in any way since I just started ignoring all the "noise" content, and i think, by ignoring it and removing myself from the pool of contributors, I'm doing the rest of the forum a favour too. I encourage everyone else to ignore the noise too, and soon enough, I think we'll find the content here improving further, while the loudmouths discover that there is no one left to preach to. Building on that, I think it will help if the moderators continue moving the noise posts to their own lonely little corner, where they can fester without affecting the rest of the forum. Anyway, I'm almost contributing to the noise myself now, so I'll leave it at that. ;)
Once again, welcome to the forum, and thanks for sharing your experiences. I'm that much more confident that my choice of rectifiers was a good one, and I'll stick with that, since I really have no intention of swapping and comparing them myself.
Regards, |
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| jcarr |
Here in Japan, the sonic changes due to different rectifiers have been noted and utilized for more than 20 years. If anything, it was the manufacturers like Fidelix, Pioneer, Yamaha etc that led the way, with the DIY community following, in many cases by using parts that were developed for or first featured in commercial amplifiers. (This is a similar situation to what has happened with audio-grade capacitors and resistors.)
In my experience, sonic differences are caused not only by the category of rectifier diode, but the manufacturer as well. Undoubtedly, HERs, FRDs, Schottkys etc. sound different, but a Schottky from IRF will also sound different from one by GI, Fuji, et al. In fact, I find that an FRD and a Schottky by IRF may sound sonically closer to each other than a Schottky by IRF and another Schottky by Fuji will.
My personal opinion is that this has something to do with the individual semiconductor processes used.
regards, jonathan carr |
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| Bobken |
Hi Jonathan,
Thanks for your comments which don't surprise me at all.
It has become quite obvious to me that (similar type) passive components from the same manufacturer all seem to exhibit 'family' sonic resemblances, and with transistors I have noticed that some maker's products are definitely different sounding from others, despite their being nominally an identical part no.
Have you reached any conclusions that you are happy to share regarding any general preferences over diodes, and who makes the most desirable ones?
During the past few months when I have been looking at the Forum as a guest, I have picked up some very useful information and ideas from your posts.
It is the generosity exhibited by members like yourself which prompted me to join up on Xmas day, and I hope I may in turn be able to help a few others through sharing some of my own experiences where appropriate.
At the very least, it may encourage others to try out some of the listening tests which I have found rewarding, and I am always interested in hearing about other peoples' conclusions, provided, of course, they are not merely based on hearsay or guesswork, and even if their perceived results do not agree with my own. |
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| lll |
Hi, it is my first post in this forum, sorry if i am not following all the rules.
I tried two times to replace my old "fashion" diodes but my teacher
in university says when use this "new" (ultra fast soft recovery) diodes as a rectifier, he notice saturation.
:bigeyes:
Giannis |
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| Bobken |
| quote: | Originally posted by lll
Hi, it is my first post in this forum, sorry if i am not following all the rules.
I tried two times to replace my old "fashion" diodes but my teacher
in university says when use this "new" (ultra fast soft recovery) diodes as a rectifier, he notice saturation.
:bigeyes:
Giannis |
Hi Giannis, I am also new to the forum, so you are in good company!
Whilst I don't consider myself to be the definitive expert on these matters, I don't fully understand your reference to the term "saturation" in connection with diodes. This suggests some kind of overload distortion to me, but I have not come accross this in relation to diodes used in bridge rectifiers.
Perhaps in translation to english the meaning has become distorted somehow, but if you could explain exactly what the problem is that you are concerned about, either I, or someone more knowledgeable than me, may be able to allay your concerns.
What is the practical or observed bad effect, or the result of this "saturation" that your teacher has mentioned to you?
Regards, |
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| Borc |
Chad!
Maybe stupid question
Is it any specific scheme to use the common cathode shottky for rectifier or can be used just one half of it? |
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| Bobken |
| quote: | Originally posted by Borc
Chad!
Maybe stupid question
Is it any specific scheme to use the common cathode shottky for rectifier or can be used just one half of it? |
Yes, you can use merely one half of a common cathode schottky, if you wish to.
Just don't connect the third (unwanted) lead.
Should that particular diode ever 'blow', you could still use the other half of the diode in its place.
It does seem to be a little wasteful though in cost, but it shouldn't normally be necessary to use all four (separate) dual diodes to make up a full wave bridge, if this is what you are trying to do.
It should be possible to arrange the layout so that you could use one dual diode for one 'side' of the bridge, and then use one half of each of two other dual diodes for the remaining 'side'.
This way, you will be using three (rather than four) dual diodes in total, and you will in effect have two 'spares' to cover for any mishaps.
Regards, |
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| jcarr |
Bob:
Thank you for your comments. It is always nice to hear words of appreciation :).
>I am always interested in hearing other peoples' conclusions, provided they are not merely based on hearsay or guesswork.<
In audio I believe that there is a place for theory and measurements as well as subjective experience. But I want to think for myself, do things for myself, and experience things for myself. And I prefer people who likewise have a willingness to think, act, and experience for themselves. Because without this, how is it possible to contribute anything unique?
I find that careful observation combined with a certain amount of educated guesswork can often be beneficial, but more frequently than not (especially on the Internet, it would seem), hearsay merely spreads mis-information around.
>And even if their perceived results do not agree with my own.<
Yes. And I don't think that agree vs. disagree is even all that different, as long as the reasons are based on direct personal experience. And in many cases, disagree is more important, because you are more likely to learn something new, as a result of receiving input that lies outside of your own experiences.
In my own audio work, I believe in combining theory, measurements and subjective listening in a mutually interactive feedback loop.
>Have you reached any conclusions that you are happy to share regarding any general preferences over diodes, and who makes the most desirable ones?<
Different types of topologies measure differently and have their distinct sound. Likewise with circuit and chassis constructions, and active and passive components. There are many variables that the individual audio designer is free to choose from, dictacted only by personal believe and preference. And the interactions arising from all of these variables can be complex, and at times, somewhat unpredictable.
Hence, questions like "who makes the most desirable parts" are not useful UNLESS you are building the same types of circuits that I do. And even among my own circuits, each circuit has a "sound of its own", and therefore has unique requirements for what should be done to it to bring it range of something that "sounds good" or is "sonically neutral" - both of which are again subjective judgements.
I think that a more useful question is not "what is best", but "what does this sound like", and "when and how is it appropriate to use this".
When we listen to different passive or active components that may happen to measure similarly, it isn't like we are trying to establish what the best-tasting flavor is. The feeling is closer to trying to establish whether what we have is tarragon, coriander, rosemary, dill, ginger, or wasabi. You would use ginger because you tasted a dish and felt that the use of ginger would benefit the flavor and make it taste good to you, but you wouldn't use ginger mindlessly on any and all dishes (at least I hope you wouldn't). On top of that, ginger may taste some differently depending on their place of origin. Ginger root from China tastes rather stronger than the stuff that is grown in Japan, and the smell is different, too.
Perhaps I will build a circuit with some types of rectifiers, listen to it, and establish if it lacks anything or has too much of something. Based on that experience, I may leave the original rectifier in place, or choose a completely different one. If I change the type, I will listen again and see if my analysis and guess were right. I am very rarely off when it comes to the basic direction that I want the sound to go in, but sometimes I may decide that I didn't go too far, or perhaps overshot my target. You get better with practice...
I suppose that I end up choosing Nippon Inter http://www.niec.co.jp/ diodes more frequently than other makes, but I also use IRF, GI, Fuji, Toshiba, Hitachi, Unison, Sanken Shinden, and others. And I may further choose Schottkys, FRDs, HERs, GaAs, and whatnot. As I indicated earlier, I may start out with something arbitrary, but I really don't know what I will end up until I go through a complete listening cycle.
Sorry that I cannot provide an answer that is succinct and neatly packaged, but that's life for you...
regards, jonathan carr |
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| lll |
Hi Bob
As far i understand he says when the diode is "on and off"
produce some oscillation (like ringing).
In my job we have spectrum analyzer up to 26.5 Ghz if you want
tell me how can i check this.
Giannis |
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| Bobken |
| quote: | Originally posted by lll
Hi Bob
As far i understand he says when the diode is "on and off"
produce some oscillation (like ringing).
In my job we have spectrum analyzer up to 26.5 Ghz if you want
tell me how can i check this.
Giannis |
Hi Giannis,
I haven't come across the term "saturation" in this context before, but I think I now understand what you are getting at, although I don't know what, if any, sonic effect this would have.
I don't have access to any such sophisticated analyzers as you do, so similarly I have not seen the effect you now describe.
My (perhaps over simplistic) view is that if the diode's current and voltage ratings are adequate (also allowing for the normally recommended tolerance margin to ensure safety and handle the surge at switch-on), there should not be any 'electronic' problem.
If any member who *knows* better in this regard is reading this and I have overlooked something here, I should be grateful if he would correct me, for all of our sakes.
As far as the sonic results are concerned, as I have said in several posts during the past few days on this Forum (and as Jonathan Carr has just reminded me!), the only way to be sure is to arrange a realistic test of the devices, loaded in a similar way to how you would use them in a bridge, and listen to the results.
Being new to the Forum, I don't yet know how to make a reference here to my other posts, but you should be able to find them by searching. I'm doing my best, but there aren't that many yet to look through as I only joined on Xmas day!
In at least one of them I have explained how I carry out some of the listening tests, together with the importance of avoiding having any unwanted influences which will spoil the results, and you may find this of some help.
All it needs is a sensible methodology and a little patience and determination, and if you cannot hear any differences (or anything wrong with the chosen diodes), then I wouldn't worry about them, whatever your teacher says, as you are unlikely to hear any ill-effects in their use.
You will probably find it much easier to make a judgement if you compare these diodes with some others you know to be acceptable, by instantaneous switching between them, rather than merely listening to a setup where they are used throughout.
Hopefully they will either sound distinctly better, or worse, but if there is no difference, go for the cheapest ones!
Fortunately, with diodes (although I guess they will change a fraction during 'burning in' as all other SS devices seem to) I have never noticed any real change to their 'sound' when used over a period of time, unlike many other components. Therefore any conclusions you reach based on immediate direct comparisons, are likely to be reasonably fair and true over the long term.
Schottky devices should theoretically work well at high frequencies, although if the problem is only at say 26.5 GHz, I guess anything could happen here, but whether any abberations at these stratospheric frequencies will cause you any 'sonic' problems, I just don't know!
Normally, "ringing" is dealt with by using snubbers, which I said elsewhere I personally don't like the sound of, but with no reverse recovery transients to worry about (again, theoretically) with schottkys, I don't know what else to suggest.
Regards, |
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| till |
| quote: | | the only way to be sure is to arrange a realistic test of the devices, loaded in a similar way to how you would use them in a bridge, and listen to the results. |
If we talk about tests, why not go on with this thread? :
http://www.diyaudio.com/forums/show...15&pagenumber=1
Would be fine if somebody could make comments.
also crown posted a link to a document with related information in the thread. |
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| jcarr |
Giannis:
While regular diodes are conducting, the junction builds up and stores a substantial charge. When the AC waveform and voltage reverse direction, the current also reverses, but until the junction charge is depleted, the diodes continue to conduct (now in the reverse direction). When the charge finally clears, the diodes turn off abruptly, creating a sharp wavefront with high-frequency content that can reach into the RF region, and the lead wires and transformer windings act as antennas to radiate this crud all over.
OTOH, Schottkys don't have any stored charge, and therefore should not cause this type of problem. However, Schottkys can also cause ringing, not in themselves, but in the power transformer. As long as the rectifiers are conducting, the transformer windings are loaded, but when the rectifiers stop conducting, the windings "lose" their termination and will ring. The solution is to add some sort of network (like a bleeder) across the secondaries so that the windings are always terminated, regardless of whether the rectifiers are conducting or not.
So much for the theory... When I actually do this I frequently end up deciding that I prefer the sound without the network in place. Ultimately, it is best to try it for yourself and make up your own mind.
hth, jonathan carr |
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| Bobken |
| quote: | Originally posted by till
If we talk about tests, why not go on with this thread? :
http://www.diyaudio.com/forums/show...15&pagenumber=1
Would be fine if somebody could make comments.
also crown posted a link to a document with related information in the thread. |
Hi,
Actually, I was already aware of this thread, and the only comments I would make are that nowhere in the entire thread (that I could see) does it tell you anything very practical or positive about how these devices actually sound. i.e. does a particular type of diode sound good in use, or not, or better or worse than another?
Also (and I am not criticising him in any way, as I would be in exactly the same position) when questioned, Icceman, who kindly put up the original rather nice 'scope pictures, admitted that he didn't really know what they meant!
The earlier post I made was to share the results of many extended and carefully carried out 'listening' tests, and my conclusion that schottkys were universally the best I had tried was readily shared with everyone who might be interested.
Similarly, I admitted that I didn't care for the sonic results I had obtained from *any* of the snubber circuits I had also tried, which appear to agree with Wayne's recent objective test on snubbers. Regrettably, Wayne didn't comment on schottkys, which Nelson said (somewhere in the Forum) he also favoured.
Presently, I don't find it very convenient to replicate my earlier tests all over again, but soon I will do so to compare schottkys (my current favourites) with the newest diodes, and I will expose the findings to anyone who might be interested.
Unfortunately, my own diode 'listening' tests were done some years ago, and the latest fast/soft diodes were not then available, so I haven't tested them A/B yet, although I have just obtained some of them to try.
I still hope that someone may have done some of these listening tests and comparisons on the modern diodes and will be prepared to share the results with the rest of us.
Perhaps if Giannis adopts my suggestion, he will be kind enough to publish his findings, especially over the concerns his teacher has expressed. i.e. does the 'ringing', or whatever has been observed, have any bad affect on the sound?
Also, maybe if I am patient, Wayne might comment on whether or not he carried out any objective tests on schottkys with their sophisticated equipment, and if so what his findings were, which will be useful to compare with my subjective trials, to see if we are also in general greement here as well.
Regards, |
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| till |
| OK, i try to find the difference in an objective way, but i donīt know if the difference in the scope pics is what we search for. I recived a lot of samples / super fast / soft etc. recovery and schottky diode samples from different companys and will use them in the alephx. I have to admit iīm not able to hear the differnce between diodes. This may be because my speakers are not good enough or because iīm simply pysicaly not able to. Iīm bale to hear differnces between door open or colsed in listening room but not between caps or diodes. Maybe this will change with other speakers or not. What i understand is there is an aestethical reason for usage of schottkys. This is my main reason to do so. From my experience, and thats subjective and not much, i have to build another listening room when the new speakers are ready, far more important than diodes, caps, induction free resistors and what ever. |
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| Bobken |
Sorry that I cannot provide an answer that is succinct and neatly packaged, but that's life for you...
Hi Jonathan,
Thanks a lot for such a comprehensive reply.
I fully understand what you say, and I should have known better than to have asked such a direct question about these diodes, or at least to have expected an all-encompassing answer, as I know full well that few things in life are that easy.
Reading what you have written, it seems that we must have trodden many similar paths over the years, although, in my case, I am some way behind you as my interest in electronics and audio is entirely non-commercial.
I don't have the advantages of doing these kinds of tests (amongst other things) full-time like I guess you do, but I don't need to make a living out of it like yourself, the pressures of which I imagine must take much of the fun out of it.
I hoped perhaps in a similar way to what I have found with say MIT Multicaps, which all seem to me to have a family semblance (although I only happen to like the rather limited [and pricey!] RTX series myself), that you may have reached a similar conclusion with regard to different makes of diodes etc.
I noticed the same kind of situation with each of the many generations of TRT's Wondercaps, Ultracaps, and Infinicaps etc, to use another example, and most other passive components I have tried do appear to exibit many similarities.
In general with active devices, I have not seen the same well-defined situation, and I maybe wrongly thought from your other post, that your findings were rather different from mine in this area and that you had your favourites as far as semi-conductors go.
From what I now understand, this is not the case, and (like me) you have found some which are favourite in some locations, and some which are better used elsewhere.
Probably the greatest benefit to me from your carefully worded reply, is that you don't appear to have reached many conclusions which differ greatly from my own, and I am encouraged by that.
As you say, it is always far better to know if someone has (genuinely) come to a different conclusion, since that way you can think afresh or carry out some tests again, and by so doing learn something valuable and new from the exercise.
I don't wish to go through life with a blinkered approach, nor in thinking that I know everything (because I don't), but I have always had an insatiable curiosity about mechanical, electrical, and electronic devices of all kinds, and have tinkered about with many of them.
At sixty years of age, I have by now gained a fair amount of confidence through experience and will therefore try anything (legal!), and never a day goes by without my learning something new and worthwhile, which is a very enriching experience in life.
What I find aggravating (and, not unexpectedly, I have already seen a little of this in only a couple of days of posting at this Forum) are those armchair experts who spout off about all and sundry when it is clear they have done absolutely nothing on their own by way of any trials or tests in the areas I have 'dared' to make some comments on, and they really don't have anything worthwhile to comment upon, themselves.
I don't mind the irritation from a personal point of view, but such juvenile acts do unfortunately inevitably tend to cast some overall doubts upon what has been said in good faith, and this may discourage some inexperienced DIYers from having a go for themselves.
This is sad, I think, as very few of us are one hundred per cent 'original thinkers', and it is frequently the spark of an idea or a comment from someone else which has set me on a new path to try something out which might not be intuitively sensible to do.
No-one likes to waste time (or money!) unnecessarily, and, as you know, some of these comparisons can take up an inordinate amount of time to do thoroughly which many cannot readily spare, but if an experimenter thinks he stands at least a fair chance of success, if he is anything like me, he will have go for himself and see what the results are.
However, if some misguided idiot has slagged the suggestion off in an apparently authoritative manner, with the support of some bogus or irrelevant facts, I guess many hopefuls will simply not bother and they will miss out on the potential benefits.
I personally don't care if anyone else's system doesn't sound as good as it might, after all there is nothing in it for me, but having discovered a few good things as a result of my efforts, I will willingly share them with anyone who is interested and who has an open mind.
When I first discovered (quite by chance) some 35 years ago that not all similar components sound the same in use, I simply couldn't believe it, and neither could the few people I spoke to about it who clearly thought I had a screw loose!
However, I couldn't deny it (since it was so blatantly obvious to me, once noticed) in spite of what the conventional wisdom said at that time, so I thought it might just be sensible to take advantage of the fact and improve the overall sound of my equipment.
I have therefore spent the last 35 years doing just that, with the first ten or so of those years in virtually complete isolation, because no-one wanted to listen to what I had to say about such apparently ridiculous beliefs.
Fortunately, in more recent times, the 'rags' began to run articles which made it obvious that, however misguided people thought I was, I was clearly not alone in my discoveries, and the rest is history, as they say!
One of the most exciting times I have had for many years, was when, relatively recently I built a computer, and then soon discovered the Internet and DIY audio forums etc.
I could hardly believe it and the generous exchange of information, especially from professionals such as yourself and Nelson, who must be a little concerned not to dilute your livelihoods too much, and I applaud you all for what you have done.
Thank you, again, for your kind response, and a very happy and prosperous New Year to you.
Regards, |
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| ALW |
| quote: | | So much for the theory... When I actually do this I frequently end up deciding that I prefer the sound without the network in place. |
Interesting, can I assume this is a properly designed snubber network designed to damp the self-resonance of the mains transformer secondaries?
I've not played with this in depth, but do know that, to my ears at least, the common (and incorrect) approach of putting caps across the rectifiers does sound worse.
Just curious, as I have every intent of trying a proper snubbing network, after I've played with rectifiers a bit.
Andy. |
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| lll |
Hi,
Thanks to all of you for the information.
When i found the time i try to figure out what really happen
with this diodes ( I work the most of the time out of Athens).
I d'ont now if the "ringing" create problems but i think the
real test is as Bob says.
Any way just i want to share any information i have in order to help if i can and to get information of course.
I d'ont now if can check sonically the diodes with super twetter.
Giannis |
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| Bobken |
| quote: | Originally posted by lll
Hi,
Thanks to all of you for the information.
When i found the time i try to figure out what really happen
with this diodes ( I work the most of the time out of Athens).
I d'ont now if the "ringing" create problems but i think the
real test is as Bob says.
Any way just i want to share any information i have in order to help if i can and to get information of course.
I d'ont now if can check sonically the diodes with super twetter.
Giannis |
Hi Giannis,
You are quite right in that 'listening' is the only definitve way to be sure in a case like this.
Since I started posting here on Xmas day, I have been amazed at the number of others who have related similar experiences to those I have experienced when 'listening' to components, and in some cases, measurements, which also seem to be generally in accordance.
Many of these observations don't seem to agree very well with theory, or what some other people have described, or what seems to be currently fashionable, but I cannot help that.
I will 'go with my ears', since these are what I use to enjoy music with, and I recommend you to do the same!
Please share any results with us in due course, as other people's views (based on *their* experiences, not hearsay) are always valuable to me.
You have a lovely Country, by the way, and I have enjoyed many wonderful holidays there.
Regards, |
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| Smithers |
Hi,
i built such a bridge using 3 doublediodes. But then i noticed that the two diodes in one housing got much warmer than the others. Therefore they had a higher forward voltage drop and the ripple wasnt symmetric at all. By the way, with heatsinks you can keep their temperature equal..
Regards,
Smithers |
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| jcarr |
In reply to ALW, I now do use snubber networks on the transformer secondaries for every amplification product that I make, and prefer the sound in this configuration.
It took some time to get the listening results to gel with the measurements, but now they do.
hth, jonathan carr |
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