Hehe I'm not trying to insult anyone. I'm aware that we are in this thread are in the top percentile of most advanced equipment users. Evenharmonics might ask where I did the survey to say 'most people' never heard it. I myself heard it after decades of building amps (more than a thousand may be) and only after using wide bandwidth transistors (this most transparent one is 90MHz).
BTW, this month I have built more than 10 amps in term of number of PCB. For one PCB, it can get upgraded and modified. A few blown up and one didn't work.
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Yeah, you might see occasional shielding over flex cables, but in general now you see sandwiched PCBs and/or canned ICs with all traces buried, no magic.
Google Pixel XL Teardown - iFixit
I've used various parts from this line of products by TDK for products with EMC issues where the problem needs to be addressed without a board spin:
Noise Suppression Sheet ”Flexield“ IFL Series | Noise Suppressing / Magnetic Sheet | TDK Product Center
Of course, the difference is we measured and identified the problem and then found an appropriate material that would be a solution, confirmed by measurements. Not every material works for every problem. Life must be simple when you're doing audio "mods" and can just dip every PCB you see, wrap cables like a burrito and call it a day 🙂.
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The Upgrade Company - Interview with David Schulte
Note the disclaimer at the bottom of the page
US10184349B2 - Apparatus having a vacuum chamber configured to convert electromagnetic waves to electricity for driving a steam generator system
- Google Patents
The same gentleman?
I particularly like the cobra snake structures (52)
Note the disclaimer at the bottom of the page
US10184349B2 - Apparatus having a vacuum chamber configured to convert electromagnetic waves to electricity for driving a steam generator system
- Google Patents
The same gentleman?
I particularly like the cobra snake structures (52)
A shame you didn't try and record it, if it was easy to hear?
Thanks for the photo - I agree with all the comments on what was done, but that doesn't reflect on you - in fact it's great that you "exposed" the internal mods!
I can see three design directives here:
a/ To comply with EMC/EMI standards.
b/ To achieve the best objective audio measurements which are deemed most important. This is subject to interpretation and budget. For example on the DAC3, they threw away around 3dB of DR to give more headroom and as such prevent digital filter generated 'overs'. Someone else might make different choices.
It may or may not be necessary to go past just achieving a/ to achieve your desired level of b/
c/ To achieve the best or preferred subjective results. It may or may not be necessary to go past what is necessary to achieve a/ *and b/ to meet your preferred c/.
I used to work for for a pretty large, technology oriented company that did their own EMC/EMI testing and had their own RF testing chamber. Despite having employed many very experienced, multi degree engineers, designs often failed the in house 'pre compliance' and required re working.
I'm looking at the cover of one the digital design bibles on my desk, The cover reads: 'High Speed Digital Design' by Johnson and Graham 'A Handbook of Black Magic'.... bit of Irony there 🙂
T
a/ Agree
b/ Agree
if you meet part A and Part B then part C is irrelevant. It seems that it's only the hi end audiophile industry that builds electronics based on subjectivity.
b/ Agree
if you meet part A and Part B then part C is irrelevant. It seems that it's only the hi end audiophile industry that builds electronics based on subjectivity.
I did say bad old days! There were a lot of issues with band changes for GSM in the mid to late 90s when mobiles were not going to suck the brains of our yoof. But when you have to make 40 million a year of something focusses the mind to get it right these days 🙂
Not forgetting the lack of EMC sealing strip added to the lid.
The issue is that you are claiming to have found some magic 'more transparent' amplifier based on your personal experience. You have no clue what most of us are listening to and throwing around concepts of 'too much reverb' to explain your magic sauce is muddying the waters. As you feel you are guarding a secret (note highly unlikely) you wont explain what you have done and people on here who have posted circuits with low ppm distortion that can double up as welding rigs are unlikely to concur that you have the golden ticket to transparency. Whatever your definition of transparency is!
riiiiight.
I explained what I have done, regarding the transparency. Use wide bandwidth video transistors! But I'm not gonna teach anyone how to make amps stable. 😀. My secrets are related with making a good amp which is related with making super stable amp. But that's not a secret right?
That's why I posted here. Not for anyone who didn't build amps. By only reading amp review etc I can usually relate if someone knows what I know. What people need to do is (1) Listen to the youtube video, then (if can hear and agree) relate with my experience (2) Design with wideband transistors and find out the benefit (3) Disagree.
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I'm not sure if we are referring to the same thing; I was referring to listening to the speakers with the TT running the lock leadout or stationary. In this mode it makes a dandy audio band seismometer. If you then crank the gain up enough in many systems you can induce feedback. If you hook the TT to a preamp and headphones while the speakers are playing, say a CD, you could listen into the room via the TT seismometer.
But agreed, I really love listening to a lot of vinyl, and until the Giles Martin remaster of SPLHCB and The Beatles (both fantastic!!), the best I have ever heard the Beatles is my MFSL vinyl set. If you hadn't heard the remastered SPLHCB, you will be shocked, Giles' remaster really brought out the true dynamics...it really has balls and shows the Beatles to be the great rock band they were.
When I put vinyl on to enjoy music, I just listen to the music, and and the obvious defects don't bother me at all.
Cheers!
Howie
This literal feedback contaminates the playback, but it is a subject seldom addressed. Given the magnitude of the feedback with many TTs in many homes, I believe it swamps many of the other distortion mechanisms associated with vinyl.
I was first forced into dealing with it in college living in a 100 year old house with wobbly floors (hung TT from ceiling). Since then (as I will not restate) it has reared it's ugly head many times, and I appreciate the LP-12 for it's isolation. There may be TTs with better suspensions these days, like the SME which I also would love to try, but for lack of bread, like the Grateful Dead....darlin....
Come to think of it I would settle for a head with hair after all...
Howie
p.s. youngun's won't get the reference and I apologize for sounding daft...again.
Howie,
In the Disco days I would use a bag of sand under the turntable. Some folks would try concrete or other solid slabs. That had mass damping but does not dissipate the energy the way sand does. Energy going into sand moves the particles and then they rub against each other dissipating the energy. That is not surprisingly why running on a dry sand beach is harder than on concrete.
BTY if you really want a head full of hair it is really quite illegal everywhere, but you can always dig one up! Very strongly not recommended. 😉
In the Disco days I would use a bag of sand under the turntable. Some folks would try concrete or other solid slabs. That had mass damping but does not dissipate the energy the way sand does. Energy going into sand moves the particles and then they rub against each other dissipating the energy. That is not surprisingly why running on a dry sand beach is harder than on concrete.
BTY if you really want a head full of hair it is really quite illegal everywhere, but you can always dig one up! Very strongly not recommended. 😉
The only problem I have with this is that the coating is black. Black. From carbon black, no doubt. And as Dan recently explained, carbon black dulls sound down. It should have been white, the coating. Titanium oxide white.
I addition, I recommend placing a pyramid over the DAC3.
More likely black from a ferrous compound.
Now placing a pyramid over audio gear should be reserved for dead gear to bring it back to life.
Years back Clair Brothers sold loudspeakers with the horn loading using a pyramid based on the Egyptian pyramid ratios.
Yes you can try to make fun of this banter, but the mass of it is really to great to make any impact.
Besides I suspect adding lots of rf absorption inside any digital audio will change something. Even if not EMI at least heat dissipation.
I think that is in large part what the folks at Oracle worked very hard to minimize with things like their soft mat and record clamp, as well controlling resonances all through the chassis. Of course there isn't much one can do about the tonearm/cart compliant system picking up vibrations from the air, though I suppose fluid damping can help with that.
I remember going to a house party back when I was in college. Lively floor and a LOT of people dancing enthusiastically, big speakers plaung very loud, and a Thorens turntable sitting on a wall-mounted shelf happily spinning away without a burble. The shelf was interesting, basically just a slab of plywood suspended by two loops of heavy twine, so not even rigidly coupled to the wall.
IMO the Thorens/Ariston/Linn suspended-subchassis tables were among the best if treated right (I don't care about perfect bounce, but wall mounting seems to make a huge difference). Linn has the advantage that they continued to develop that platform, but I think Oracle perfected the idea (literally turning it upside down).
This goes to the heart of the matter. No doubt, you are both most agreeable people, character wise. Nice to be with, fun to do some listening tests with, nice people.
However, the word 'agreeable' means something. Agreeable people tend to agree with each other, because agreeing ensures an agreeable atmosphere. The wish to remain agreeable has led people astray in sorely felt ways.
In general, the wish to remain agreeable is even stronger than the temptation to lie to oneself. At all levels of consciousness.
So in order to get reliable results from listening tests, the first step is to stamp out all others. Listening under peer influence is bound to result in shared, erroneous results. The second is to take one's self out of the equation as much as possible, by at least blinding the test so that your innate biases cannot impact on the results.
I have a bag of sand in my old Micro Seiki 🙂
The resonance of the wood chassis is it's weakest point.
regards, Gerhard
It is bloody stupid enough🙂. In the summary: the core is held at a vacuum and filled with at least one inert gas.
And furthermore: the invention consists of a magnetron or somesuch electromagnetic wave production apparatus, followed by doubtful means to derive ... electricity from these electromagnetic waves. Only with a conversion efficiency above 100% this would appear to make sense.
Same issue in my current hovel. Not only wobbly floors but not connected to the walls in certain places. I do need to see how much the shelves resonate with music though.
Until I went for the suspended shelf solution I used a bright star setup (which I could have DIY'd but too lazy at the time. This was an air bladder in a box with a sandbox on top. It didn't work that well, the turntable rocked back and forth as you raised the lid and it looked fugly. Probably explains why they didn't trade for long...
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