It's a fact, as I said. Easily obvious type thing, I have no doubt you could hear it yourself if you were there. Too bad you weren't, we would be very happy for you to see for yourself.
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A good example on how to **** up an otherwise perfectly good engineered DAC-3. What a shameful scam, painting the board all over with some goop and claiming it shields EMI better than a clever designed PCB. And protecting chips with EMI absorbent, how the hell are the space technologies not adopted these “methods” yet. I’m about to bet both the goop and the absorbent have some special quantum properties and both are derived from top secret military research.
But nothing is more shameful than two individuals, driven by a gross lack of knowledge and understanding of the EMI basics, and/or a vested interest, praising this BS squared. If you have any diplomas in EE, you should burn them before somebody finds out and exposes you.
Needless to say, I am beyond disgusted. And yes, I am rude, and purposefully so. Promoting this crap is an insult to everybody’s intelligence, common sense, education and experience.
Conformal coating, tin foil. Of course, all the jumpers are still untouched and so is the 20 pin JTAG connector among the others that have been pointed out. What a joke.
I was trying to be kind, of course, this is actually what is happening. Still, putting your phone on top of another 2.4GHz intentional radiator operating at higher power levels isn't likely to improve your Bluetooth experience in terms of distance and dropouts.
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Just curious, how did you listen yo the amps without the speakers and vice versa? Did Richard have some alternative amps as well?
Unfortunately, no other amp tried at this time.
So how do we know?
Partly, we know because amp distortion sounds different from speaker distortion, as Earl Geddes pointed out long before I did. Easy to hear the difference, its just a matter of learning what to listen for. Vocal and instrumental harmonies make plain IMD consequent to HD. Amp IMD is normally more likely associated with higher order HD and the associated IMD, especially so for switching amps. Speakers tend to exhibit lower order HD and IMD effects. Its not hard to tell by listening in some cases, and in other cases where the amps have less high order distortion it can be more difficult.
Partly, also because I am privy to some design information from former JBL engineer friend of Jam's who is very familiar with the M2 drivers and Crown amps used for M2. He kindly provided some information about how to make the speakers perform at their best, and he said to the effect that getting rid of the Crown switch-mode amps would give the biggest step up in sound quality. I think he may be been involved in the design of Revel speakers while still at JBL. Anyway, there is no question the Crown amps are designed and marketed as PA amps, not home hi-fi amps. They have features that are good for the PA sound market, and are not a very good match for near field critical listening, IMHO. Don't know how JBL came to pair the amps with the M2 speakers. Maybe it had to do with impending breakup of JBL engineering by the present owners, i.e. no money for developing a well matched amp solution. That part of the story remains somewhat of a mystery.
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Right. There were multiple requests for pictures and descriptions. I agreed to do it knowing how some tend to respond. Obviously, it was done for those that wanted to see the information they requested. Now that they have a picture and a description, if they feel dissatisfied, not something I can control. All I can do is refuse to accede to such requests should similar occur in the future.
Recently saw a 24" by 36" by 4" surface plate (kinda beat and not pink) for sale locally for $100US, complete with stand. If I had a forklift I'd have been more tempted. Have always used the old Discwasher brand corian-ish turntable base, inevitable warps and all. Just a sucker for brute force solutions I guess.
Today my Jico Ruby stylus arrived, for Shure type V-15 V and Ultra 500. Stylus alignment looks as perfect as I can tell with stylus microscope and eyeballs, with an elegant looking geometry. Mounted nude with a clear glue on the ruby cantilever, which has four flats ground along its length, but no drilling down the axis, so solid. Not a beryllium tube like the originals (RIP), but available and affordable-sorta. Tomorrow's the big day! Will report results if interesting.
All good fortune,
Chris
I agree with Mark... and, we did not have to strain to detect any changes. Both heard the same things, the same way. Each of us agreed with one another as to what this and that sounded like on certain music being played.
I try to avoid the use of the word 'better', but sometimes it iS better. Better to me is either more details revealed or more accurate sound... more like real musical instruments.
The most accurate sound for the day was with digital out of CD Mastering player to the DAC-3. The analog outs just didnt do as well in any regards.
So, in conclusion, emi/rfi shielding/absorption helps when in tight quarters.
THx-RNMarsh
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Needless to say, I am beyond disgusted
Agree. And thanks to Mark and Richard to show what has been done to the DAC3 and to review the sound differences. But I also want to express some opinion:
I have found some 'solutions' to prevent EMI/RFI are actually detrimental to sound quality. So in this case, the solution is analogical to medicines. It is detrimental and not wanted unless there exist bigger problem that it will remove.
By that logic, the disgusting solution here might have benefit if we expose the device to strong EMI/RFI. Regarding to this, my solution has been to pay great attention to pcb and wiring so the prevention effort can be left out. But Indiglo has shown that Benchmark (it seemed) didn't do that at the same level of attention as I would have.
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Without measurements it is entirely useless conjecture. What if his mods actually made it worse and you like the sound of worse? How would you know it actually reduced EMI? You don't even have a theory as far as where it is important to mitigate this so-called problem?
Anyone that isn't a hack would have had to do measurements to confirm the mods did anything. So this guy that performed your mods should have before and after measurements with at the very least a nearfield probe, spectrum analyzer, and fixture? Or by measuring the analog outputs.
How come cell phones dont have any of this goop? They require good shielding and PCB layout in incredibly tight quarters to not cause receiver desense, self-interference, or fail emissions.
Anyone that isn't a hack would have had to do measurements to confirm the mods did anything. So this guy that performed your mods should have before and after measurements with at the very least a nearfield probe, spectrum analyzer, and fixture? Or by measuring the analog outputs.
How come cell phones dont have any of this goop? They require good shielding and PCB layout in incredibly tight quarters to not cause receiver desense, self-interference, or fail emissions.
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You are deliberately misquoting what I said and I didn't assume anything other than Benchmark engineers would be aware of rfi/emc design methodologies and would have incorporated those into the pcb layout and what would be most likely is a 4 layer pcb. If you have engineered any high speed digital or rf pcb you would be aware the rfi/emc is integral to the design.
Consumer and industrial electronics need to meet mandatory emc/emi compliance standards all over the world and the Benchmark DAC3 would have been tested against those standards to ensure the product complies and can be sold into those markets.
Is DAC3 four layers? What for is the ferrite beds at the RCA input?
What I am/was saying is: If we know how detrimental a 'remedy' usually is, we would pay more attention to the basics, such as pcb routing and wiring, such that we don't need to add external detrimental solutions. You mentioned how the molex cable could have been shielded too (I know what you meant). I prefer different kind of connector. The one used in RF is expensive, so what? In my own DIY implementation I chose to direct solder.
I was trying to say that, as ridiculous as it is, the solution is not 100% wrong. If I were Richard I would remove the solution if possible. But we don't know how good the device is in term of protecting itself from emi/rfi (is it 4 layers? I don't think so) and in Bangkok the situation can be different.
Back in the bad old days it was not unknown for some of the screening cans to have a blob of RAM inside the case. however there were extreme bollockings dolled out for needing to do that. In Phones the biggest EMC improvement of the last 30 years was giving up on the RF connector for a car kit (remember when your cellphone holster had an external ariel?) . Since then they've got a lot better at this stuff.
Exactly. It's the same argument that someone has to repeat and is then shot down for. Richard has a vast array of measuring equipment I believe?
with the lid down I cannot hear groove chatter even next to the turntable. I consider it low next to all the other issues that give vinyl its 'character'. It's not accurate, but it's fun!
I was trying to explain what 'transparent' amp is (which I'm sure most people have never heard). The issues that can brutally exposed is not the kind of clanging aluminium sound, or lower resolution due to compression. One common issue is too much reverberation information. This also unlike clanging aluminium, can sound 'nice' to some, but not to me. Here is a recording which has too much room reverberation (if your amp cannot produce it, just see the room condition in the video). Natalie Merchant's Motherland:
YouTube
It is at least 4 layers, if not 6 or 8 I would guess based on component density and little use of the top layer for routing. 4 layer boards are dirt cheap now.
From pics, it looks like the ferrites are on the center conductors of both the inputs and outputs and I think the RCA common is directly tied to chassis via the connector. Seems like this is already a good setup considering emissions and susceptibility.
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Insulting all our equipment is a good way of winning friends and getting credibility.
So the DAC in your DAC-3 is better than the DAC in the CD player? Not sure that is unexpected.
And to clarify this is still using the AD-DA chain in the crown ampliers?
Oh and happy kicking the Brits out day to all our left pondians.
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