I don't know who The Great One is, but I was absent due to the very odd and most uncomfotrtable pain im both my legs. Saw the medical core, did my lab tests, took my X rays, the works. Lab people told me they could write a book based on my results, incredibly good, especially since I'll be 61 in two months, only my sugar level was at 7 rather than the usual 6-6.5. Actually, at sugar level 6, I have no idea which planet I'm on, my personal ideal level is 6.8-7.2, so 7 is literally my ideal state.
The toxicology report is now in its fith week (sic!) in coming. Criminal! A man could die before they did it Those !"#$%&/()=?*? idiots.
I'm a bit better now, but no thanks to the medical profession-at-large. I can walk, but I'm limited in distances. And this just ain't IT!
Glad to see you gentlemen are still around. I hope I find you in good health and better spirits.
On the electronics front, I've been playing around quite a bit, now that I'm limited to home more than before. It's been an exesperating experience, I just can't get Thorsten's suggested architecture to come to life, any kind of life. Obviously, I'm missing something, I shall have to consult with Papa Thorsten on this. It seems innovative to me, I've never seen anything like it before, and I have hopes for it.
Also, I got hold of the service manual for a Spectral preamp, so I assume I have seen Demian's work. I need to spend some time with it, but what I did like straight off was its ellegant simplicity.
I've also come up with an architecture of my own, which is really an evolution of an already well known topology, but it shows unusual promise. Perhaps with more work, I can get it to do even better before I make a live model. It's based on my Centurion project, but evolved.
Speaking of the Centurion, the heat sinks should be arriving any day now.
And I do have some questions I picked up along the way.
The toxicology report is now in its fith week (sic!) in coming. Criminal! A man could die before they did it Those !"#$%&/()=?*? idiots.
I'm a bit better now, but no thanks to the medical profession-at-large. I can walk, but I'm limited in distances. And this just ain't IT!
Glad to see you gentlemen are still around. I hope I find you in good health and better spirits.
On the electronics front, I've been playing around quite a bit, now that I'm limited to home more than before. It's been an exesperating experience, I just can't get Thorsten's suggested architecture to come to life, any kind of life. Obviously, I'm missing something, I shall have to consult with Papa Thorsten on this. It seems innovative to me, I've never seen anything like it before, and I have hopes for it.
Also, I got hold of the service manual for a Spectral preamp, so I assume I have seen Demian's work. I need to spend some time with it, but what I did like straight off was its ellegant simplicity.
I've also come up with an architecture of my own, which is really an evolution of an already well known topology, but it shows unusual promise. Perhaps with more work, I can get it to do even better before I make a live model. It's based on my Centurion project, but evolved.
Speaking of the Centurion, the heat sinks should be arriving any day now.
And I do have some questions I picked up along the way.
Gee, thanks Wayne, I think I'll just lay down queitly and die.
Maybe I'll get lucky and it ain't arthrtis, maybe it's just common cancer.
Perhaps I'll just go cyborg on you.
With shugar at 6, I am all dizzy and like stoned, that's simply too low for my organism, I don't dare go below 6.5. At 7, I feel great. At 8, I don't feel so good any more. No, that's not the source of my problems, trust me, it's something else. Not to worry, I will track it down.
Dave Wilson - anything to do with Beach Boys? Or is it just a coincidence?
I have not seen a copy of that document is 30+? years. The design evolved a bunch after the manual was created and Spectral has been very proprietary about service. I could probably mark up the changes after the document was created pretty easily. It may help others trying to fix one. Perhaps you can scan it and send the scan my way? I could also explain anything unusual about it.
If anyone else wants to see how they did it, I suggest you go to:
HiFi Engine | Download Free User/ Service Manuals, Amplifier, Receiver, CD, Tape, Tuner, Video
register for free and get a daily quota of 20 downloadable files.
Do look in their Library section, LOTS of choices there.
HiFi Engine | Download Free User/ Service Manuals, Amplifier, Receiver, CD, Tape, Tuner, Video
register for free and get a daily quota of 20 downloadable files.
Do look in their Library section, LOTS of choices there.
Why do you think so?
I find that some (not all, of course) designs from those days still sound better today than most new designs. Case in point - Marantz 170 DC power amp. I changed all of the capacitors and beefed up the main caps, up from single concentric 2x12.000uF/56V to 2 discrete 22.000 uF/63V. And my ears tell me it's still a damn good amp - not perfect of course, but it can stand next to most newer ones and walk away smiling.
Since I have not heard ANY Spectral products thus far, I cannot comment on them specifically, but I will always allow for the possibility that they are just as good, or better, today.
A good sounding device will always remain a good sounding device. It just may not be as good comparatively to its competiton, meaning that great then may be just very good today.
John Curl Vendetta phono preamp and many of Erno Borbely designs are of the same vintage as DMC 10 preamp, but are much more advanced even today. Dual complementary J-fet inputs are always better than differential.
DMC 10 is really well executed in conctruction details. But power supply is the most basic, we have learnt much in the meantime.
It reminds me of early Threshold units- simplest circuit executed with gold plated wide traced eye catching PCB-s, good enclosures etc.
Life is short, built the best you are capable to.
DMC 10 is really well executed in conctruction details. But power supply is the most basic, we have learnt much in the meantime.
It reminds me of early Threshold units- simplest circuit executed with gold plated wide traced eye catching PCB-s, good enclosures etc.
Life is short, built the best you are capable to.
There is no intrinsic reason a complementary Jfet input will work better. At high frequencies its no longer complementary anyway. The big benefit is the lower noise from paralleled parts but the linearity is not necessarily as good. As you point out execution is more important than circuit architecture. As for power supply perhaps the sophistication is not where you think to look. Isolation from the AC line is easily 10X more important than reduced ripple or low impedance, especially if the circuit is designed to deal with those issues.
The later versions of the DMC-10 added a number of small but significant enhancements.
Forgive me for being so direct, but I have to ask: since you speak of devices which are ultra rare even in the USA, have YOU actually heard them yourself, in order to comment on them?
I have many times heard devices which were technologically superior to other devices, yet did not manage to equal the other devices in terms of actual sound. Not too rarely, as Demian says, it's the actual building execution which carries the day.
Over the years, making and selling power line filters, I can only abolutely agree with Demian's view that keeping the junk out of your power lines is by far the single most important aspect of power supplies, although of course other aspects are also important - just not as important.
Only the approach varies. Some people take care of that inside the devices, while I believe it's best to get rid of that problem before it even enters the device. Also, my approach allows me to use the "Virtual battery" approach to regulating the input stage and VAS sections, I simply do not need complex circuits to deal with AC junk coming in through the grid. And I hope we'll all agree simpler is more reliable, assuming that simplicity is not paid for elsewhere.
Also, my appraoch offloads the power transformer(s) as well, a not an insignificant factor in itself, since the vast majority of the junk never even reaches the tranformer facilities. This makes the transformers approximately 10% more effcient.
Therefore, my appraoch might lead one to believe that I was heavily "saving" money on PSU regulation, when in reality my lines end up being cleaner than most. Not to even mention the current gain section, which has no other regulation than simple electrlytic capacitors.
Circuit diagrams are always good indicators of audio equipment performance.
I have never listened to DMC 10, but I compared my dual differential complementary devices to similar non complementary gain blocks with expected results. DMC 20 and 30 are probably more elaborated, but DMC 10 is a passe design. Complementary circuits have I would call it , natural reduction of distortion by inherent design.
Direct use of lm317/337 regulators are not allowed in modern high-end, especially with MC cartridges.
I have never listened to DMC 10, but I compared my dual differential complementary devices to similar non complementary gain blocks with expected results. DMC 20 and 30 are probably more elaborated, but DMC 10 is a passe design. Complementary circuits have I would call it , natural reduction of distortion by inherent design.
Direct use of lm317/337 regulators are not allowed in modern high-end, especially with MC cartridges.
Its virtually impossible to evaluate your own product. The biases are enormous to overcome.
Please send the High End Audio Police my way, because I won't bow to that kind of prejudice. Power supplies need to be designed for the specific application. Some places need particular supply requirements. I posted possibly the lowest noise power supply ever here, but its specific to crystal oscillators. Its not appropriate to this application.
I design for performance, not for fashion. I don't get lost tweaking something that won't make a big difference. The DMC 10 has a lot of supply isolation (three isolated sections per amp) and PSRR so it doesn't need the extreme power supply effort the typical complementary Jfet designs do. I'm getting as much as -110-120 dB distortion from that typical "non complimentary" differential design. That is not happening with the complimentary stuff. I have discussed this with John Curl and he agrees, and points out that those distortions are probably not significant in audio, something I agree on as well. We are both focusing on the higher order stuff, which can plague any design. The DMC 10 works great for moving coil applications (leaving me asking why you need a more exotic power supply). The typical example can get to less than about 3 nV/rtHz and with simple upgrades to below 1 nV/rtHz. Important is the low input C along with the low noise.
I think the layout of the DMC 10 is one of the most important aspects and its not visible on the schematic. Here is a teardown of a first gen DMC 10 (same gen as the schematic) All equipment shold be designed with such care/insight! - AudioKarma.org Home Audio Stereo Discussion Forums
If you like and are comfortable with complementary inputs that's fine, but its no indicator of the final performance.
Please send the High End Audio Police my way, because I won't bow to that kind of prejudice. Power supplies need to be designed for the specific application. Some places need particular supply requirements. I posted possibly the lowest noise power supply ever here, but its specific to crystal oscillators. Its not appropriate to this application.
I design for performance, not for fashion. I don't get lost tweaking something that won't make a big difference. The DMC 10 has a lot of supply isolation (three isolated sections per amp) and PSRR so it doesn't need the extreme power supply effort the typical complementary Jfet designs do. I'm getting as much as -110-120 dB distortion from that typical "non complimentary" differential design. That is not happening with the complimentary stuff. I have discussed this with John Curl and he agrees, and points out that those distortions are probably not significant in audio, something I agree on as well. We are both focusing on the higher order stuff, which can plague any design. The DMC 10 works great for moving coil applications (leaving me asking why you need a more exotic power supply). The typical example can get to less than about 3 nV/rtHz and with simple upgrades to below 1 nV/rtHz. Important is the low input C along with the low noise.
I think the layout of the DMC 10 is one of the most important aspects and its not visible on the schematic. Here is a teardown of a first gen DMC 10 (same gen as the schematic) All equipment shold be designed with such care/insight! - AudioKarma.org Home Audio Stereo Discussion Forums
If you like and are comfortable with complementary inputs that's fine, but its no indicator of the final performance.
dvv -- add 40mg of Zinc to your supplements. Sugar will drop immediately.
If you dont get enough zinc in your diet, you cant make enough insulin. Zinc is also needed to make Testosterone.... which will add strength to aging muscles.... largely diminished at old age.
This helps with the PS generated noise; View attachment How_Amorphous_Magentic_Noise_Suppressors_Work.pdf
THx-RNMarsh
If you dont get enough zinc in your diet, you cant make enough insulin. Zinc is also needed to make Testosterone.... which will add strength to aging muscles.... largely diminished at old age.
This helps with the PS generated noise; View attachment How_Amorphous_Magentic_Noise_Suppressors_Work.pdf
THx-RNMarsh
I agree in part. To some extent, a circuit can be some indication of what to expect assuming the one evaluatting the circuit has EXTENSIVE experience with circuit topologies, and tha one being evaluated in particuler. However, even so, it's only an indictation, far removed from a sure thing.
I have been surprised quite a few times.
I disagree. That is indeed so in theory, but I have also heard quite a few fully complementary designs which I managed to forget in 2 seconds flat, just as I have heard classic single ended input amps which defied theory and managed to sound wonderful.
Ditto for any topology you care to name. It's not so much the topology as it's how well one applies it.
Again, I have heard and seen a few designs which leaft me yawning, and others which did a great job. Just enough to make it impossile to tell in advance with any certainty.
I'm with Demian on this, the key factor for me is a power supply especially designed for that one particular job, even if it does follow some general rules. If any rule could be singled out, I think it would be that overall, I find simple regulation circuits to be better than very complex ones. Perhaps I am oversimplifying the point, but I think circuits with shorter propagation times usually sound better than very complex ones. Not a must, but high probability.
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Thank you for the advice, I will try it out. I've tried a lot out already, but other than calcium and potassium (which I am notoriously short on, inherited from my dad, I'm a tomato junkie), nothing else seemed to help.
LM317 is stable if the ESR of the output caps is high. No ceramics, film, polymer, etc allowed !... Plain-old electrolytic is fine.
Of course for phono preamp duty there are much lower noise / better options... but it has its uses.
I seem to recall having read somewhere that fully complementary circuits indeed do tend to reduce harmonic distortion, however of of even harmonics only.
Unfortunately, those are the ones our ears seem to like, while they object to odd harmonics
In my experience, a simuator can predict the quality of sound to a degree if one looks at the harmonic decay behavior of a circuit. If the decay rate is more or less as expected, up to 11th harmonic where applicable, with a more or less even decay rate, you can assume such a circuit will probably sound well.
I trust my ears. Spectral use brute force approach to filter regulator noise( 100R+120 mf). Now we have rely good regulator designs- hybrid or fully discrete. I am using Borbely all-fet fully discrete series regulators, and for me they are the best but simple enough to build.
Simple series feedback free follower regulators ( early Krell types) are too primitive for modern designs.
Simple series feedback free follower regulators ( early Krell types) are too primitive for modern designs.
Chicken Soup....
.
Selenium is another deficiency to watch out for and can be associated with Zinc deficiency.
Two Brazil nuts per day should ensure correct levels, gobble a few more daily in the short/medium term to get your levels up.
I read somewhere years ago that cancer patients are universally deficient in selenium.
Get well soon, Dan.
http://ods.od.nih.gov/factsheets/Selenium-HealthProfessional/
http://www.stopthethyroidmadness.com/selenium/
Oysters are the cure for testosterone problems
.Selenium is another deficiency to watch out for and can be associated with Zinc deficiency.
Two Brazil nuts per day should ensure correct levels, gobble a few more daily in the short/medium term to get your levels up.
I read somewhere years ago that cancer patients are universally deficient in selenium.
Get well soon, Dan.
http://ods.od.nih.gov/factsheets/Selenium-HealthProfessional/
http://www.stopthethyroidmadness.com/selenium/
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