Showing 1 of 330 conversations about:
coolerking
156
Jun 7, 2018
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WHY THE MICRO USB INTERFACE?
I am not implying that you are trying to save money with the connector. I am saying that you have apparently "selected" an interface that is what specified by USB-IF consortium for essentially small light cell phones, not 2 or 3 pounds immobile desktop units. The very small and somewhat sensitive female connector is going to be worked, stressed and fatigued, it is not robust.
What concerns me is 2 things: 1. Your ODM ( manufacturer ) is doing your layout design and probably the passive and active component selection. Which means you are ignoring these signal integrity issues that will present themselves when you meet production (I do not mean the hand pick and probably hand built eval boards given out to INDIVIDUALS to be reviewed.) 2. For a $350 product you have eliminated the entire market of higher grade USB (non micro, non mini) cables that is available. Before you go off on "Those are expensive and unnecessary" I am using a very robust nice PYST USB cable from Schitt available at $20.
3. It is a crappy interface. Plain and simple. Where ever there is a physical interface it becomes an analog issue. Meaning a signal making contact at the interface, but poorly, is going to wreak more havoc in the signal path. It is not a simple digital issue, it works or it does not.
BTW, using individuals to review your products sickens me. For one thing they are not accountable and make comments like this: Worth noting: the USB connection is a microUSB rather than the standard full-size connection we normally see on desktop DACs. This has to do with size (the RDAC is not very tall) but also longevity... microUSB supposedly has a greater operation lifetime than its full-size counterparts, and USB C is not ubiquitous enough to be a good fit here. I thought this was weird and sort of annoying when I first encountered it. Now I'm used to it and don't think it's a big deal.
Nothing against the individual, it sounds like he has been misled. You want us to believe you cannot fit a USB 2.0 male B connector in your design, gee the Schitt Bitfrost is 6.75" to your 8.1" and they seem to manage it. And where the hell did the "greater operation lifetime" idea come from? Good god anyone even without back-end QA experience can look at a USB B interface vs a USB micro interface and see where you are going to have problems. Unfortunately, some of your customers have a lot of experience in these matters. Manufacturing, design, sales, marketing, Hardware consortium (USB-IF) and committees (IEEE), semi-conductor, FPGA's, ODMs, and the nefarious dealings of Shenzen and the like.....
I am smelling a lot of BS and snake oil. You are not containing your marketing, its too aggressive and short sited. You are going to piss off those in the "know" first, and others later. MD will become "New audiophile hobbyist beware" I had higher hopes with you all. MD could have really stretched out the point of diminishing returns on the cost vs performance curve.
Jun 7, 2018
Mp29k
65
Jun 7, 2018
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Let’s not jump to conclusions on the component selection etc. Massdrop has a good reputation for build quality. I however won’t be buying this because of the micro USB. Ive had too many fail. It was a phenomenally bad decision on their part. If it isn’t too late to change to a robust USB-B, i‘d recommend it. Audiophile products, except for tiny slim phone DACs and amps don’t use micro usb for a reason. It sucks!
Jun 7, 2018
Frogmeat
347
Jun 7, 2018
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The USB input on my FiiO X5ii that I got from MD 2 years ago just quit working on me, and it is a micro input, and had problems with others, but never with a standard USB-B.
Jun 7, 2018
JDWarner
323
Jun 7, 2018
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Micro USB is specced for greater insertion cycles than full size USB. Bigger is not better, lessons have been learned along the way. C would be even better, but micro is an excellent port.
https://electronics.stackexchange.com/questions/18552/why-was-mini-usb-deprecated-in-favor-of-micro-usb
Jun 7, 2018
zbells
187
Jun 7, 2018
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You might be able to insert it more times, but that's not super relevant. I don't think micro USB holds up as well to the stress associated with moving wires around and having them at weird angles while it's plugged in (in my experience at least).
Jun 7, 2018
Fayne
1364
Jun 7, 2018
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I'm sorry, do you unplug/plug your DAC many times in a day? I sure as heck don't. That is just bloody crazy talk. It gets plugged in and left there.
I very much do do not want a unit that relies on a port that WILL break or detach from board when taking lateral stress. USB-B connectors typically have larger (more solid) connection points to the board and enclosure.
Jun 7, 2018
coolerking
156
Jun 7, 2018
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There is an entire eco-system built around USB , primarily cables. If you say cables are not important, then you are saying that $350 is too much for a DAC. Get it?
What experience are you basing your comment on bigger is not better comment? Not the article you point us to, that is evaluation between mini and micro. Not straight USB.
Once again, what experience are you basing your comment on? Plain old USB is a solid interface. The reason it was changed was because the desire to move to smaller platforms. I was at Intel in the mid 90's, Andy Grove and co. saw the future back then, and knew uP's where moving to smaller platforms, and subsequent changes needed to be made to all their interfaces. RJ-45 has never been changed because there has not been a reason in Ethernet.
Once again, what experience are you basing your comment on?
I am really tired of folks like yourself misleading people. The folks on this board are mostly non Audiophiles maybe becoming Audiophiles. They are going to give up, it is upsetting. Maybe your intentions are good. Please explain yourself.
Jun 7, 2018
coolerking
156
Jun 7, 2018
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I do not mean to jump to conclusions, I just understand this business. I really hope MD will respond, and be honest. There are real electronic veterans out here on this board that will not comment and just walk away. I just bought there o2 headphone amp. It is solid, I like it. I am a fan.
Jun 7, 2018
Mp29k
65
Jun 8, 2018
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Exactly. Even cable weight (assuming you could get an audiophile micro usb cable (no snake oil, just robust strain relief and great shielding) can mess them up.
Jun 8, 2018
JDWarner
323
Jun 8, 2018
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I'm an audiophile who happens to also be a physicist and engineer with doctoral level DSP experience as well as experimental high energy physics experience where we chase noise with more advanced tools than we have time to get into here. Hopefully that satisfies your attacks on my credibility.
Suffice it to say that there are times to consider an aftermarket cable and others where you should not. And yes, I'm well versed in the difference between them. And yes, I am unapologetic when it comes to the difference; there is an entire industry around selling gullible people snake oil here. Believe me or not, your call, but I speak from a position of empirical knowledge and confidence in what I am saying few can match.
Analog audio is one place where a studio quality cable is justified. Notice that I take care in my choice of words: studio quality means Blue Jeans Cables. Not hundreds of dollars. The difference this makes is by far the highest for the lowest level signals, so in decreasing order of importance: phono, source to pre, pre to amp, and speaker cables. This is only for analog signals.
In contrast, USB cables for DACs do not require esoteric or upgraded cabling, full stop. If you feel better when your USB cables have stiff Techflex around them, maybe with some upgraded weights stuffed in or fancy colors, maybe with a magic black box in the middle, I've got bad news for you: what you're hearing is the placebo effect. The sound of that money leaving your wallet made more noise than any difference you'll ever hear. A USB ground isolator or -with some scepticism- a reclocker is the only thing that might have any relevance. Not the cable at all, unless it's a horribly out of spec knockoff.
So cables can be relevant, but not anywhere near as much as as a good R2R DAC. This thing can and should be connected with any solid, standards compliant version of a micro USB cable. Hopefully I made this clear, and honestly busting some of the cable snake oil makes this a much more accessible hobby than those who say you should invest anywhere near as much into cabling as the rest of the system. My cabling is probably under 1/25 the value of my system, and I do not suffer because of it - audibly or in terms of measurements.
Jun 8, 2018
Mp29k
65
Jun 8, 2018
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I’ve got a darkvoice on the way. Who knows if I made the right call, but I like tubes and they are fun to mess with. If the AAA 789 amp ever drops again, I’ll probably get that for an objectively “perfect“ amp.
Jun 8, 2018
killerwingnut
24
Jun 8, 2018
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Well that touches the aftermarket cables, but what about the micro usb vs full size that most of Coolerking's last post was all about?
Jun 8, 2018
JDWarner
323
Jun 8, 2018
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First, while that link doesn't cover it standard USB is only specced for ~1500 insertion cycles. Mini ended up being pretty bad, while micro is an order of magnitude better at 10,000+. You can find anecdotal evidence of micro-USB issues people have had, but understand there is a massive bias here: you aren't plugging in and unplugging your printer 10,000 times, and the mobile devices everyone has used continually with micro-USB put way more strain on that jack routinely than your typical USB-B interface. Thus it's disingenuous to say "I've never had a problem with USB-B" because you're basing that on low double digit interactions with that jack... while on the other hand your phone from a couple years ago likely used micro-USB for years, daily or more frequently, with no problems.
Robustness is in fact built into the micro-USB jack spec, taking into effect a lot of past lessons learned - including from USB-B. It is not out of place on a desktop product; it's the best jack widely available save USB-C, and they didn't go with that one for reasons clearly stated. I've actually resoldered USB jacks (very fine work to do by hand), and these things have big ground lugs which also serve as structural support for the jack, never mind anything else.
It boggles my mind that anyone would be doing stuff which would repeatedly put severe orthogonal strain on the input jack of a valuable DAC, but even if you're one of those people, this jack is in the middle and would functionally be protected by the adjacent power and RCA jacks - not to mention the fact that the DAC should be relatively lightweight. I would venture that you could pick it up by the micro-USB.
My turn: Armchair experts opining without evidence about the supposed fragility of micro-USB should pony up actual evidence. I'll wait. Keep in mind lots of people said similar stuff without any evidence when Apple's Lightning connector was released, not to mention mini-DisplayPort, not to mention USB-C, and have been completely embarrassed since.
Jun 8, 2018
Mp29k
65
Jun 8, 2018
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I just know the first failure point in all my kids tablets is the micro usb. And nearly ALL high end cables are USB A TO USB B.
Jun 8, 2018
JDWarner
323
Jun 8, 2018
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I'm going to need a citation for that unproven assertion about lateral stress when it comes to micro-USB. I'll wait.
Also, realize the adjacent RCA, DC barrel, and possible additional digital inputs will all serve to protect this port even in the unlikely case you want to regularly abuse the back of your DAC.
This is honestly ridiculous.
Jun 8, 2018
JDWarner
323
Jun 8, 2018
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"nearly ALL high end cables are USB A TO USB B"
There's your problem. Don't buy those.
Jun 8, 2018
Mp29k
65
Jun 8, 2018
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Wait all you want, guy. I’ve had at least 5 fail on tablets and other devices well before I expected it. for the ones that havent failed outright, they get loose and lose connection requiring us to hold the cable “just so” to charge it. I’ve had exactly ZERO failures with USB B with multiples more devices that have used them for 10’s of years longer. Mini and micro usb simply do not make sense on anything other than small portable devices where nothing else will fit. (You’re not going to change my mind).
Jun 8, 2018
Mp29k
65
Jun 8, 2018
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Are you one of those guys that believes the cheapest, unshielded USB cable works as well as a well shielded, gold plated usb? I’m not talking hubdreds of dollars “Audiophile“ cables. I’m talking heavier cables with true gold plating and several levels of shielding. Not to mention cables that separate the power from the signal.
Jun 8, 2018
Fayne
1364
Jun 8, 2018
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Have you looked at the board pictures? While the RCA and DC barrel will protect it some, that there micro-USB looks like a basic surface mount. Maybe with a tiny through hole post or two. I nope the heck out on that. Drop something on the cable or snag it with something else and you're liable to pop that bugger out of place.
One of the most common failure points on modern gear. You can dig that up yourself, or not. I'm just tired of having to dissect gear and re-flow crappy connectors into place. Use the right connector for the job.
Jun 8, 2018
Mp29k
65
Jun 8, 2018
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A-friggin-men
Jun 8, 2018
JDWarner
323
Jun 8, 2018
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Gold has no significant effect for USB, but go ahead and go for some bling if it makes you feel better.
Every USB cable that meets spec is going to be shielded. Some have wasted metal or sand (for real) in there to make you feel like it must be better - and this is depressingly effective. As you say yourself, 'heavier cables ... with several levels of shielding' - these are not at all better when it comes to USB. Sorry, intuition has led you astray.
Take apart the standard in physics and engineering labs sometime - a 75-ohm BNC cable. It's got a single thin layer of shielding, and the actual cable is going to look and feel very diminutive. These power our understanding of the universe, in labs that - if significant improvements could be made at ANY cost - they would have been long since. What I'm saying here, is weight has very little to no bearing on digital signal transmission.
Now if we're talking a 5 horsepower electric motor, you'd better look up the gauge of your wiring and spring for enough copper to handle that current. It'll be heavy by necessity. But for high frequency signal transmission, more copper is actually often not better.
Jun 8, 2018
coolerking
156
Jun 8, 2018
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JD. I do not have the time for this. You are contradicting yourself. 1. You reference an article about mini vs. micro when i was speaking to USB, which the majority of cables, and desktop DACs use. You have no evidence to back up your claims. You say you have empirical evidence, what? 2. The digital input on the DAC carries the digital signals, and it carries noise that infects the clocking and power sensitivities . It is a multi-variable situation. It cannot possibly be explained in this forum.
I have done design, marketing and to this argument, product support and sales at semiconductor companies that sell into customers in the Computing and Network Equipment Manufacturer, also an FPGA company, probably the one this DAC is using. My customers buy in high volume, on the magnitude of tens of thousands units sold. At this volume you come across Everything, and I mean Everything. FPGAs and IC's have extreme sensitivities to power and ground noise, no matter what their literature indicates. When a problem hits a fortune 500 customer of your customer, and you come together to determine root cause, all pre-conceived notions such as:
In contrast, USB cables for DACs do not require esoteric or upgraded cabling, full stop.
GET THROWN OUT THE WINDOW. FULL STOP. Because noise can come from anywhere, and effect unknown sensitivities and can cause esoteric happenings.
These kind of all knowing statements are normally made by designers during the pre-meetings before meeting with the customer, or the customers customer. Then I along with senior management have to tell the designers to keep their mouth closed, and only answer what they are asked. They just do not have the experience. It takes years.
I have seen so many problems coming from so many different places. Remember, this is the input. Any disruption to the signal integrity at the beginning of the conversion amplification chain gets propagate through, and almost always in the signal integrity worsening. You can understand that theoretically.
So I have learned something thru all this experience:
The more I know, the more I realize how much I do not know. This is mature concept, I understand.
I have spent a lot of time researching Digital cables from empirical evidence volunteered by many many folks offered on Audiophile boards such as Audio Asylum. I also took an album I can listen to repeatedly, Astral Weeks by Van Morrison, and listened to it with a PYST, with a much more expensive borrowed one, and an Amazon one. Meaning listening to the album repeatedly, over a period of three months (it can be done probably only with the mysticism of Astral Weeks), PYST works for me. I go purely on enjoyment, and lack of listener fatigue.
But this is useless argument, that has been played out before. I am responding to your generalization of myself as:
If you feel better when your USB cables have stiff Techflex around them, maybe with some upgraded weights stuffed in or fancy colors, maybe with a magic black box in the middle, I've got bad news for you: what you're hearing is the placebo effect . The sound of that money leaving your wallet made more noise than any difference you'll ever hear .
No, I can handle $20. (Remember, I mentioned Schitt's PYST in my original post).
Respect that i am speaking from real experience in the trenches, sitting on IEEE 802.3 physical layer committees in addition to working on PCI (et. all), Infiniband and appropriately USB-IF consortiums. Also, from 10 years of working in semiconductor ATE testing where one of my jobs was to optimize "the contacters" on the test head that grabs the chip while it is fully tested within a second or less. Here small highly inductive power and signal paths are anathema to eliminating false positives and negatives (rejects).
Here is another mature concept that I learned from my customers who freak out when you introduce a change that is not required, even though through all types of proof you can guarantee it will not cause problems. If is not broken do not fix it.
But this DAC has decided to fix an interface that is not broken, I have not ever heard one audio enthusiast complain about the USB interface, and say we got to go micro. Not one. Show me one, please.
And good lord, you still have not given us a reason to make the change then some obscure reference that is meaningless.
Finally a piece of advice, making comments like: I've actually resoldered USB jacks (very fine work to do by hand), and these things have big ground lugs which also serve as structural support for the jack, never mind anything else. Tells people that you are a hobbyist who dabbles in Hardware. Anyone working in the hardware industry that can garnish the type of experience you seem to have, would have technicians available to them. Now if your a technician, then I can respect that. -
Jun 8, 2018
JDWarner
323
Jun 8, 2018
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And yet, despite not having time for it, you manage to write a small essay revealing what you do not know. This is just full of ad hominem attacks and isn't a good look for you. Reported. I'll let my previous comments stand; hopefully you can move toward engaging in actual discussion.
Please note that I did already say there is at least a theoretical place for a USB isolator, but in that case you're defending yourself from the source rather than extraneous noise. I absolutely stand by my statements that on either side of the isolator, any standards-complaint USB cable is entirely sufficient. I have nothing against Schiit, and the PYST is a good cable. I do have something against a $600 USB cable with special magic fairy dust applied. You seem to think this was an attack, and lash out in response, where it would appear we agree.
If you really have experience in the trenches as you say, you'd know that high energy physicists and engineers absolutely do their own work. It's not farmed out, go grab the oscilloscope and get to work chasing down problems. Again, attacking based on pure speculation is insulting. Please refrain.
I will only engage you further if you stop this behavior.
Jun 8, 2018
Brosefstalin42
255
Jun 8, 2018
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Oh boy. Investigate the crapstorm that was the Nook Color USB cable. The input jack on the tablet was, typically, fine. The actual connector on the cable that went into the tablet, oh boy. Those things broke like no tomorrow.
Now, if you want a poor female port, look up the Nexus 6. My old 6 has a very loose connection, and many others have had the port fail so they have to rely on the Qi wireless charging to get their phone charged.
Now, I did also have a Blue Snowball where the USB-B port was loose, but that was because I adjusted its position and the angle is just terrible with it (45 degree between ground and parallel to ground) so it wouldn't stay plugged in. I found the Usb-mini connection on the Blue Yeti better because of both positioning and lighter cable from positioning again (moved several times and always trying to find a good position to minimize PC case noise pickup).
Lightning seems to be a bad connector if you aren't using Apple cables, so I'd never want to go that way (knockoffs not powering properly at all times).
USB-C has been amazing. All they have to do is throw in a USB-C to USB-A cable and they solve their worry about people not having that cable. In fact it would be better than their RCA cable thrown in, since most of us have an unbalanced DAC with those cables already.
I've seen all but A and C (and mini to a lesser extent but all that have those are PS3 controllers, Blue Yeti, and cheap SD card MP3 players) fail so far or have issues with connectors one way or another, and have provided consumer examples for USB-micro in two different ways. USB-micro needs to die when we have C. There is no excuse anymore.
Jun 8, 2018
CEE_TEE
3434
Jun 8, 2018
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Hello coolerking and others! The micro-USB seems to really be an issue on this DAC. We are actually using a special jack that is longer and reaches all the way into the metal back panel. This way, the rear panel acts like a strain relief and helps mitigate stress up and down or side to side. The connector itself is rated to higher operational cycles per lifetime.
I will check to see if we can switch to USB-B without affecting the timeline.
Jun 8, 2018
vkennedy61
14
Jun 8, 2018
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At a minimum it should be a USB C connection. It's what all the cool kids are doing. My phone is C and it's a rock solid connection. It's been almost a year with countless connections for power, headphones, IEM, and as a source to a DAC. It hasn't weakened or loosened. Frankly I've had very few problems with Micro, but the industry seems to be shifting to C, I don't see a reason not to adopt it here.
Jun 8, 2018
zbells
187
Jun 8, 2018
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Awesome reply @CEE_TEE. It's great to know you took special precautions to reduce the strain on the jack. However, does that mean the cable that is included is not quite the same as a standard USB C cable?
Jun 8, 2018
CEE_TEE
3434
Jun 8, 2018
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It was slated to come with a regular USB-micro cable. (Can I just say that I have so many cables and adapters but I hate looking around for USB-B cables?) But we are using a jack that reaches into the rear panel, Will wondered on his sample RDAC why his USB cable stuck out more than usual and the cable is average.
OK: I have seen all the comments here and there is a pretty clear community mandate to revise the USB-micro to B. Things have already set in motion to change to USB-B. (USB-C would be a change in cost and timing.)
Jun 8, 2018
jsmiller58
648
Jun 8, 2018
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WAIT, hold the presses... are you saying the design is going to change? All due respect to JDWarner’s spirited defense of the micro interface (and no doubts about your expertise in any matters), if it is going to be redesigned to USB B, I am going back in on this drop... please confirm...
Jun 8, 2018
CEE_TEE
3434
Jun 8, 2018
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Confirming that the new plan is to switch to USB-B. China has been asleep but everyone who has been awake has agreed to make the switch.
Jun 8, 2018
jsmiller58
648
Jun 8, 2018
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And as quick as that I have rejoined the drop!!!
Thank you!!!!
Jun 8, 2018
MarcSpence
179
Jun 9, 2018
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Great! Smart move
Jun 9, 2018
null24
23
Jun 9, 2018
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Awesome! My preference would be USB-C of course, but anything is better than micro USB.
Jun 9, 2018
coolerking
156
Jun 9, 2018
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I was looking for an explanation as to why, and you provided. I thank you.
If I was in a financial position to be an early adopter, I would join the drop. I am excited about what you are trying to do. If the initial feedback is positive (the pieces all came together), than I will be buying one.
I let my emotion get away on my last post, but re-reading it, I think the damage I did was mostly to myself by almost providing my resume ~ a very silly thing to do.
Despite that the quality of audio has been reduced in the last 40 years in favor of accessibility, cost and ease of use, the time is now for it to swing back. The culture/community around "vinyl" is doing their part, always have. Dre and Jimmy Iovine did theirs with Beats (many people ditched their apple earbuds). The challenge though is that analog electronics is damn near impossible to fully understand, even for folks that are "technical." With my breadth of experience, as I have said, the more I learn, the more I realize how much I do not know. But, places like MD can pull the technologists already on here into this daunting world. Audio is highly subjective and a multi-variable mess (not black and white, not digital, not zero-sum gain). Your audience is going to strive for objective, quantitative and "digital" reasons to make the jump into Audiophile world. I just hope you provide killer products at a digestible price that these folks will take the leap of faith an buy. And some day they will realize that they have just sat around with their friends, having an adult cocktail, at then end of the day in the sun, listening to a HiDef drop (perhaps of 'Astral Weeks' ;~) ) a couple times in a row, and have all enjoyed themselves, even though only a few sentences have been spoken. I think that fits into MD over all vision, people can trust that MD has figured out for them what Audiophile product works at the right price? I think that would benefit the whole damn industry, and it is why I get so damn pissed when I believe I see it going the other way.
Peace
Jun 9, 2018
coolerking
156
Jun 9, 2018
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JD, my intention was not to attack. Mostly ;~)I was trying to make a point, that some of us are drawing on experience, not just blindly sucking down snake oil. (BTW, I can drive a scope). In an environment where you will see the insidious nature of noise because of the reach and volume of your products in the field .......soldering has become specialized to technicians, It is just too time-consuming and difficult for anyone else. They are surgeons, have all my respect and are always available for help.
Be well
Jun 9, 2018
jsmiller58
648
Jun 9, 2018
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Hopefully you and JDWarner will have a long and creative future discussing and debating product and feature merits!
I for one enjoyed your and JDWarner’s exchange. While the “popcorn” factor was maybe a little higher than necessary the reality is that the rest of us learned a lot from the exchange - and hey, look at it this way, your discussion influenced the design in a positive way!
Jun 9, 2018
Huxleigh
83
Jun 9, 2018
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I'm always pleased to see such responsiveness on Massdrop's part to customer requests. Nicely done.
On a standalone desktop component, substituting a full-size receptacle for the micro-B input is a change that I suspect many will find preferable. And it is easier to find well built USB A-B cables that reliably meet the parameters of the USB 2.0 specification in audio applications than alternatives.
Jun 9, 2018
CEE_TEE
3434
Jun 9, 2018
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Thank you for participating in the discussion JDWarner. Sorry we landed with USB-B.
Jun 9, 2018
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