The Headcase Stax thread

[Dusty Chalk]

28 minutes ago, swt61 said:

Why are you still here ...

I can actually answer that -- he doesn't read as well as he writes.  The analogy I draw is Trump's tweets.  There has been great backlash at his tweets, but does he change his ways?  Nope.

[Craig Sawyers]

17 hours ago, kevin gilmore said:

I was referring to audio transformers in the audio path. And i'm sure you know this. I have tested a number of lundahl input transformers, and besides being very sensitive to even the slightest amounts of dc, they have 2nd harmonic greater than the .05% you state

There are ways around that problem, and also the tendency for distortion to increase significantly as you go down in frequency. Lundahl don't tend to mention this too loudly, but distortion of 0.1% at 50Hz and >0.5% distortion at 20Hz are not uncommon at higher drive levels (~5dBu).

The way around this is to use the technique that Audio Precision do with their galvanically isolated inputs. This uses a very carefully designed transformer with auxiliary windings driven by an active circuit with negative output impedance. Patent is here  http://www.google.co.uk/patents/US4614914 . It needs very careful design, because if anything is out of kilter it can of course make a very nice oscillator.

[wink]

3 hours ago, astrostar59 said:

Wow, a lot of time to write that. Impressed. Hmm, I post about stuff I have either owned, or heard. I don't say anything is garbage unless I hear it first. I understand there are others more knowledgable in technical matters who can do that. Respect. But I post as an audiophile who likes decent sounding gear. Simple. I don't join in the bully club. Now if you enjoy that sort of thing, maybe you need help.

It is with great melancholy that I put fingers to keyboard after perusing your answer to my previous missive, as it is very evident that the vital information contained therein has either been disregarded in a most cavalier manner or disregarded due to the lack of sufficient education or desire to glean the freely provided data and so it behoves me to correct some of the most blatantly obvious mistakes and inconsistencies contained therein as well as your previous postings which are quite evident to those with even a smattering of technical and experiential knowledgeability especially when you deride a most well known designer and builder of enormous repute as well as deign to question his obvious expertise in these matters whereas you, it seems, do not even understand the rudimentary differences between an amplifier and preamplifier as well as the most desirable specificational requirements required to occasion their performance at the most elevated level in that which is known as high fidelity and can be found in this forum in copious quantites in a plethora of pertinent threads, and yet the most flagrant of disregard for truth in performance is evidenced in your complete misunderstanding as to what constitutes real hi-fi which terminology seems to be highly misunderstood by the great unwashed who sadly equate this term with "sounds good" whatever that means whereas even the least careful thinker who would care to apply the logical extension of the terminology used would realise that if the source material sounds rotten then anything that would make that sad situation more tolerable is of necessity not even close to high fidelity and, as the sad situation is propagated on this as well as other forums to misinform and demean those gullible newbies who take this situation at face value in the severely mistaken belief that their new-found knowledge which they are avidly imbibing in has not even a skerrick of fact in reality and it falls on myself to inform you that you appear to be one of these poor benighted souls who have drunk from the polluted pond of misinformation, scuttlebutt, hype and popular myth and then you severely add to the odious problem by regurgitating this technical and practical diarrhoea as if it is twenty four carat certified truth to be consumed and digested as well as regurgitated to the next generation of poor susceptible victims of all this snake oil, unicorn tears, pixie dust, hens teeth and lastly but not least of all downright dishonesty to the cause of better reproduction of the individual's selected choice in the reproduction of sound in the most felicitous manner.

Edited November 27, 2016 by wink

[spritzer]

The funny thing about astrolube is utter lack of understanding of anything.  So tubes must the be the same as all other tubes, "cuz toobz be magical!!"  As it happens and I've heard two of the top end Lapazitor dacs and what utter turds.  Seriously, this stuff is so bad that you have to question the sanity of the people to claim this is high end or they just don't grasp the concept of high fidelity.  You know, the annoying bit about the end result being as close as source as is possible... 

Let's not go into how Lapazitor is built or designed.  One of the Carbon owners was adamant that this was the true solution to all DAC's and even sent me some of the correspondence with the owners.  Yeah...their idea of a power supply design is to listen to two equally sucky versions and then pick the winner.  Who needs to measure noise and shit like that? 

As for the MSB dac...well that is my dac in the pictures and I can safely say that everything he stated is utter bullshit.  This unit was bought directly from a dealer and the only upgrade done to it was replacing the USB input as there was something wrong with the original one.  The rest of it left the factory like that. 

[nopants]

I still appreciate that he came out to say something, even if it didn't amount to much. Certainly a lot more level-headed than when cavalli stopped by to grace everyone with his presence. Maybe I've also been desensitized but I didn't even think people were being too "flame"-y about things either haha

Also Lampizator is some sort of sick joke, all it takes is a quick peek under the hood. But it's magic, has to sound good right? To this day I wonder what the wood is for

Edited November 27, 2016 by nopants
fixed picture

[Craig Sawyers]

A few years ago I managed to persuade my lady wife to accompany me to a high end audio show. This particular one was to showcase British Hi-Fi, and was in a hotel near Heathrow. We walked into one room, and a track that we knew particularly well by Marc Cohn was playing. Carole actually burst out laughing. I hustled her out with a hissed "Bear in mind that these guys have tried really really hard to design something that sounds that awful". Effort in designing a product is absolutely no guarantee that it will sound decent, and may actually sound acutely awful. One of the reasons that the infant (and not so infant) mortality rates in audio start-ups is to high.

[Dusty Chalk]

I don't think he understood the nature of Kevin's response when he called him a wimp and then went off on a tangent about why exactly it was sensible to stoke a healthy respect for high voltages.  Some people just want to watch other people get weeded out of our gene pool.

I know I do.

[JimL]

6 hours ago, wink said:

Astro, perhaps, if you took the time to know somewhat of the topic you were posting about, and before you took it upon yourself to sarcastically call out those far more knowledgeable posters contributing in the various threads in this forum, you may not be the continual equivalent of soylent green and comic relief that seems to be your undeniable forte whilst you attempt to add to the tenor of this forum and this thread in particular, but sadly, it is my melancholy duty to inform you that your postings are comical at best, and asinine in general thus resulting in the many negatory replies to your posts, and, adding to the status quo, your total inability to, or perhaps complete disregard for the rebuttals your posts receive, you continue to chronically suffer from the proverbial foot-in-mouth disease, and contrary to popular belief, this post is not a diatribe against you but a rather belated attempt by myself to attempt, perhaps, not futilely, to educate and admonish you with the intention of rescuing you from further displays by yourself of your penchant to display your ignorance of the subject matter and it's context which is so necessary to the understanding of the postings herein contained, plus it also has the added benefit of ameliorating the comical content of the ever present contrarians who just love to point out your fallacious understandings which are so frequently proffered in your posts for their amusement and delectation but to the detraction of your personal prestige within these hallowed portals of knowledge and dissemination thereof, which has contributed massively to those here with the right attitude and resulting in their elevation of worth, knowledge and skills in DIY as well as other areas of social interaction as can be readily seen and recognized within this forum, and so I hope that this slight rebuke is taken in it's proper context as an educational expose which will no doubt be seen as negatively impacting on the fun factor by those who are awaiting every post of yours to ascertain what mileage may be derived from your ignorance which is overtly expressed in you posts and to be butt of ridicule and demeaning jesting from the more astute and enlightened denizens with a greater than modicum of humour and irony.

I must admit I really admire your patience, perspicacity and erudition in crafting such a sagacious response to a relatively brief comment.  You must have a lot of time on your hands.

[Craig Sawyers]

Back in the day, we got involved in building high field resistive magnets. The idea was that you would discharge a very large number of capacitors through a thyristor bank into a magnet. This was shrink fit into a thick stainless steel tyre to stop it from exploding as a result of hoop stress. Now that was a beast you did not want to share a room with; testing them was a bit of a game so as not to incinerate the test engineer

600V? Chicken feed.

Here's a shot in a concrete bunker that this kit was installed. The blue things heading off into the distance were the capacitors.

 

Edited November 27, 2016 by Craig Sawyers

[JimL]

5 hours ago, kevin gilmore said:

pabbi1 at canjam2010 drove my T2 into clipping. you could hear it across the room. He was very happy. Everyone else was scared

there were others that stopped by my office and roughly the same thing.

Double WOW!  Per OSHA, recommended time of exposure to 110 db dBA is 30 minutes.

[Sechtdamon]

I have 3 things to say:

1st: I really do not understand why people listen that loud. Even with my 252s I couldnt go further than 10-11 o'clock. I mean shit. Driving T2 into clipping...

2nd: I was admiring you guys, Today I admire you more. I couldn't stand against astro or his bs after 2-3 posts, I stop posting against his posts yesterday, He is really tiring. You are really good. So:

 

3rd: I feel guilty/ashamed now for I own a dac with tube (2c51 variants) buffer; MHDT Lab Atlantis. IMHO, It sounds good to my ears but. If you want to see inside of it:

 

It uses one Ad1862 per channel as i know, Dr. Gilmore. It sounds pretty analog, but tad bit forward sounding. I paid 860 Dollars for it, including shipping. I bought it cuz of curiosity, as always. It turned out good sounding one.

Here is a closer look to the dac chips:

 

PS: This post has no sarcasm.

Edited November 27, 2016 by Sechtdamon

[kevin gilmore]

the big yellow caps are the output caps, the 2 analog devices chips are likely the dac chips (can't read the numbers) then discrete solid state buffer then tube output stage with what seems to be a current source for the plate. 2c51 a better choice than most tubes. only one resistor mod in the lower right corner. depending on how much it costs, possibly a decent deal.

[Sechtdamon]

Deleted and merged into another post.

Edited November 27, 2016 by Sechtdamon

[astrostar59]

3 hours ago, wink said:

It is with great melancholy that I put fingers to keyboard after perusing your answer to my previous missive, as it is very evident that the vital information contained therein has either been disregarded in a most cavalier manner or disregarded due to the lack of sufficient education or desire to glean the freely provided data and so it behoves me to correct some of the most blatantly obvious mistakes and inconsistencies contained therein as well as your previous postings which are quite evident to those with even a smattering of technical and experiential knowledgeability especially when you deride a most well known designer and builder of enormous repute as well as deign to question his obvious expertise in these matters whereas you, it seems, do not even understand the rudimentary differences between an amplifier and preamplifier as well as the most desirable specificational requirements required to occasion their performance at the most elevated level in that which is known as high fidelity and can be found in this forum in copious quantites in a plethora of pertinent threads, and yet the most flagrant of disregard for truth in performance is evidenced in your complete misunderstanding as to what constitutes real hi-fi which terminology seems to be highly misunderstood by the great unwashed who sadly equate this term with "sounds good" whatever that means whereas even the least careful thinker who would care to apply the logical extension of the terminology used would realise that if the source material sounds rotten then anything that would make that sad situation more tolerable is of necessity not even close to high fidelity and, as the sad situation is propagated on this as well as other forums to misinform and demean those gullible newbies who take this situation at face value in the severely mistaken belief that their new-found knowledge which they are avidly imbibing in has not even a skerrick of fact in reality and it falls on myself to inform you that you appear to be one of these poor benighted souls who have drunk from the polluted pond of misinformation, scuttlebutt, hype and popular myth and then you severely add to the odious problem by regurgitating this technical and practical diarrhoea as if it is twenty four carat certified truth to be consumed and digested as well as regurgitated to the next generation of poor susceptible victims of all this snake oil, unicorn tears, pixie dust, hens teeth and lastly but not least of all downright dishonesty to the cause of better reproduction of the individual's selected choice in the reproduction of sound in the most felicitous manner.

I don't join the bullshit club either. You however seem to be putting yourself up for top technical bod, the one who decides who is a looser, who knows how much about equipment, indeed who gets the personal attacks and assignations. It is termed 'cyber bullying' I believe if it is taken out of context of the subject (hifi discussions).

As I said, I put emphasis on comparison by contrast. I use my ears. Many here know the technicalities of good design as well, that is why I like to read here. I don't say I have such knowledge, but I know what I hear, and Kevin's KGSShv and Carbon designs are superb sounding amplifiers. I have had the delight to have owned such amplifiers for 4 years, and before that 20 years of Stax amps and various headphones. So I don't see myself as a newbie as such. Rather an oldie with IMO decent ears. I haven't built an Electrostatic amp but I have built a tubed pre-amplifier, and 3 x tubed DACs. I enjoyed that experience immensely. 

[Torpedo]

Astro.. you may use your ears, but you're not using them for the purpose they were designed for. Please save us from further crap

[johnwmclean]

Calling Dan and his permanent shovel....

[guzziguy]

You can do this yourself.  Just add him to your ignore list and, voila, you've banned him.  There is a caveat here.  Tapatalk doesn't seem to know about ignore lists.

Mostly, just don't feed the troll and he'll go away.

[swt61]

59 minutes ago, astrostar59 said:

You however seem to be putting yourself up for top technical bod, the one who decides who is a looser

I'm imagining some guy with a wrench, running around loosening bolts. If I found some asshole doing that I'd call him a loser.

[mypasswordis]

Sechtdamon, have you been to a headphone meet? First thing I always do is crank the volume knob way down before I listen to any gear. It's pretty eye opening how loudly people listen... pabbi1 is on a completely different level from most, but there's no doubt he has some level of hearing loss.

[Sechtdamon]

21 minutes ago, mypasswordis said:

Sechtdamon, have you been to a headphone meet? First thing I always do is crank the volume knob way down before I listen to any gear. It's pretty eye opening how loudly people listen... pabbi1 is on a completely different level from most, but there's no doubt he has some level of hearing loss.

Yes my good sir, I'm also an active member of a Turkish Forum; Techno-fi. I went couple of meetings and also hosted couple of mini mettings. I cannot listen to gear as loud as most people, not even 1 song. I'm listening to My egmont at 9-10 o'clock with my sr-207 (Dac's output is 2,8V). Once I entertain a guy, who listened srs-2170 system at 3-4 o'clock. I've never been WTFed that hard before.

When I'm about to experience new gear, I put amp's pot to minimum, then I roll it to a comfortable level. Yes, I go loud for a one passage of a song for reviewing (to see how the gear reacts)  but listening to them at more than 80-90ish dB, naah.

 

Well if he has hearing problems, then that situation may be normal(?), I guess. But isn't listening that loud worsen the problem?

Edited November 27, 2016 by Sechtdamon

[Dusty Chalk]

I don't see the problem with a tubed DAC, just don't claim it has more fidelity than one without a tube.  Tubes add a very pleasant distortion that nicely ...uh...counteracts? ...digititis.  <-- See that word, 'distortion'?  That's the opposite of fidelity.  However, in small amounts, it can add euphony to a system, and that's certainly why I listen -- for the almost euphoria.

Wink -- run on sentence much?  There were multiple thoughts there, so maybe ... stream of consciousness much?

[dsavitsk]

3 minutes ago, Dusty Chalk said:

I don't see the problem with a tubed DAC, just don't claim it has more fidelity than one without a tube.  Tubes add a very pleasant distortion that nicely ...uh...counteracts? ...digititis.  <-- See that word, 'distortion'?  That's the opposite of fidelity.  However, in small amounts, it can add euphony to a system, and that's certainly why I listen -- for the almost euphoria.

None of this is actually true. The problem with tubes in a DAC is that they are high impedance devices with low transconductance. That makes them less effective as buffers, and less effective as low input impedance devices for IV duty. They also tend to be a little noisier. 

Moreover they are lower distortion devices than transistors. They sound good in spite of any distortion they might add - not because of it. As a cure for digititis, whatever that might be, tubes will do precious little.

Arguably they are useful to add some gain (perhaps in a DAC with a simple resistor IV) where they may be superior to transistors.

[Dusty Chalk]

Interesting.  Thanks for the correction.

[Dusty Chalk]

Well, except for the part about why I listen to music, that was correct.

And I definitely find tube distortion pleasant.  When I first got that unpronouncable chinese amp, it distorted like crazy, but I couldn't tell, because it made everything more pleasant.  It also removed any detail -- any detail -- but definitely added euphony.

Also, I read a theory somewhere (Bound for Sound?) that said that the way tubes distorted -- fewer higher order harmonics? -- was less offensive to the ear than the way transistors distorted, and therefore transistors needed lower distortion numbers, otherwise the distortion was more easily heard. 

Moreso, that the nature of the higher second order harmonics tended to mask the the spurious frequencies created by harsh digital filters.  

Debunk or confirm?

[dsavitsk]

Seems more or less correct to me. In general less distortion sounds better than more, and low order is less offensive than high. Most people can tolerate a bunch of 2nd harmonic distortion and very little 7th for example. Exactly how much is unclear, and how much 7th you might be willing to tolerate for no 2nd (or vice versa) is also unclear. Some of us are also willing to tolerate slightly more 3rd to eliminate the 2nd (and this seems to be a divider of preferences).

What is clear is that the brainstem amplifies dissonant sounds and diminishes concordant ones, and that how much your brain does this is dependent upon a lot of factors, including musical training. Additionally, if you take a distortion free signal and purposely add 2nd harmonics to it, it won't sound like a tube amp. It will just sound worse than it otherwise would have.