Schiit Audio Magnius back panel photo courtesy of Schiit Audio. The larger 3 pin sockets are the AES balanced input and output connectors.
As with other topics in audio, balanced audio connections are shrouded in myth and mystery. This article introduces some of the basics in a non-technical way. Reference [6] from Benchmark Media takes a more detailed look at pro verses home differential connections and some of the myths surrounding differential mode connections and amplifiers. Reference [8] also from Benchmark Media talks about differential headphone amplifiers.
Read Carefully and Be Careful What You Read
This is engineering, not politics. Alternative facts don’t exist, but fried equipment does. Miss-wiring an amplifier’s output stages can activate the protection or destroy the output stages. Transistors have a disconcerting ability to protect the output fuses of classic amplifiers. Modern amplifiers like Schiit Audio’s Vidar use electronic protection of the output stages. Be sure to follow amplifier user guide wiring instructions.
I’ve listed all of the references I used to create this article. I encourage you to at least read the Benchmark Media articles from their knowledge base. Benchmark’s audience is pro recording and mastering studios and the creatives who own and run them. Benchmark is all about getting its clients to put their money where it matters to build a high value mastering system that is clear and transparent until it needs to be colored to make judgements about how a mix will sound over typical audience playback systems.
Featured image courtesy of Schiit Audio for use in this commentary.
Some weeks ago, I wrote about the addition of Modius to the Dismal Manor’s Dismal HiFi. Modius is a digital to analog converter. In my system his primary duties are to make YouTube audio from the TV listenable and to play WHRV-FM streamed audio from a HiFiBerry Digi+ stream receiver. Modius does those jobs brilliantly. Neither is a high definition source so don’t merit a Gugnir channel. Multibit Gugnir (Gumby) is my primary music reproduction converter used for CD, Qobuz, and TIDAL playback.
Modius provides a significant improvement in TV sound and WHRV-FM sound over using the premap’s internal converter. American Public Media Live from Here rebroadcasts via Modius match Gumby in sound quality. Modius is consistently beating the WHRV-FM on air sound in spite of the low 128 kbps MP3 used.
Schiit Audio has done it again with a new $200 amplifier called Magnius that continues the value proposition in headphone amplifiers. This is an ideal amp for an office system or armchair listening position in the lounge. Modius and Magnius are intended to be a high value personal audio system. Magnius provides outputs for both balanced and single ended headphones at this price and has both balanced and single ended inputs. Modius can send a single ended signal to the HiFi and a balanced signal to a Magnius at chair side for individual listening in a shared listening space.
Featured image courtesy of Apple, Inc. for use in this commentary.
In the summer of 2019, Apple launched the Apple Card in partnership with Wall Street bank Goldman Sachs and transaction interchange network MasterCharge. Apple made a fuss over its titanium substrate and elegant looks. Others give their attention to its interest rates, limits, fees, and cash back features. Truth be known, the Apple Card is a better than median deal for most but not a fee leader or interest rate leader. But it is the first 21st century credit card. After the break, I’ll explain why.
15 August 2020, correct inaccuracy regarding magnetic stripe.
15 August 2020, how do I pay my Apple Card bill?
15 August 2020, Added shimming reference
15 August 2020, Added glossary and cleaned up terminology to make it consistent with the world.
15 August 2020, Added compromised card procedures
18 August 2020, Apple Card does not work with Quicken, Banktivity, etc.
Glossary
EMV Europay, MasterCard, Visa consortium specifying the chip and pin interchange network protocol and chip to reader protocol
NFC Near field contactless protocol used on air between a payment terminal and a account holder token or mobile device.
EMV and NFC transaction use the physical card number. The physical card number takes its name from the fact that it is baked into the chip embedded in the card.
Card Not PresentNumber my shorthand for the full card number you can read in Apple Wallet. An easily replaced virtual card number.
Physical Card Number Apple Wallet name for the card number used for NFC and EMV transactions. Last 4 shown. It is encoded in your titanium card hence physical card number.
Device Account Number Apple Wallet name for the card number used by Apple Pay transactions. Last 4 shown.
21st Century ???
So why is the Apple Card the first 21st century credit card? Because it is the first designed exclusively for use with modern payment interchange infrastructure. The minimal design is striking. Nowhere on the card is there a card number, an expiration date, or a magic number for use in manual transactions.
The card itself can be used in chip-and-pin readers that support the EMV protocol described in reference [3]. It also has a magnetic stripe allowing it to be used with the deprecated stripe reading terminals.
Second, it is designed for near field radio contactless payment devices in partnership with Apple iPhone and Apple Watch.
NFC reader image courtesy of Google and NFC Times trade paper.
Apple iPhone is designed for use with near field contactless readers like the one shown above conducting a transaction with Google Wallet on an early Android device. Any transaction point showing the radio waves and card symbol is able to conduct near field contact-less transactions. In the Apple ecosystem, Apple Wallet lets you select a card and carry out the transaction. Note that Apple Card itself does not have the radio parts imbedded, just the EMV card present parts.
Apple Pay and Apple Card are integrated. Any transaction point supporting Apple Pay works with iPhone Apple Wallet and with Apple Card EMV transactions. NFC transactions require that the transaction point have the proper radio parts included.
Note that Apple Pay is an optional protocol with most merchant services providers. Some include it as a free configuration option. Others bleed the merchant for a bit more vigorish to support Apple Pay. Apple Pay is offered to merchant services folk and the interchange carriers without cost. As merchants replace readers, they are adopting EMV/NFC protocols and Apple Pay as checkout is quicker and more secure.
Apple Card is about Security
Goldman, MasterCard, and Apple designed Apple Card to be identity theft resistant. It can only be used for EMV transactions. No numbers on the card to be photographed. Yes, servers photo cards for later exploitation.
The card has multiple card numbers, one for each payment channel. There is a virtual account number card not present transactions. There is a physical card number for EMV and NFC transactions initiated by the card. There is a device card number for Apple Pay transactions. You can change the virtual account number after each use if you wish.
The Apple Wallet App shows all “completed” transactions, here completed means that the EMV, NFC or Apple pAy protocol has run from start to finish without error and an accepted status was received. You’ll also see failed transactions.
Fraudulent Transactions
Fraudulent transactions become a lot more difficult as the card must be present for most transactions. The card may be present directly, or the transaction can be Apple Pay or Apple Cash Pay if you have set it up. The EMV protocol works via hashes and transaction IDs. There is no point in the transaction where your card number is exposed to be stolen. There is no strip to copy during the swipe. There is a name on the card so you can retrieve it from your server but no other PII on the outside of the card. What there is on the card is encrypted in the EMV secure enclave on the card.
Use the last 4 of the account number to identify which of the three numbers was compromised. Report the compromise to Goldman. Goldman will carry out its fraudulent transaction procedures to reimburse you.
Activating Apple Card
Order Apple Card using Apple Wallet on your iPhone. Apple creates a card matched to that iPhone and Apple ID. Only the ordering iPhone is able to activate and use the card. Its a cryptography thing (public key and private key). To activate the card, open Apple Wallet and place the NFC antenna over the marked spot on the card’s shipping wallet. The two talk to deliver the phone’s half of the cryptographic key pair. Apple has the other half. The phone saves off its key in the secure enclave (that pesky trusted computing stuff). This cryptographic trickery complies with the EMV protocol allowing any EMV NFC reader to conduct an Apple Card transaction.
Apple Card is a Credit Card
It does not have a PIN. Some European points of sale may require a PIN for all cards. If so, you’ll need to use another card at these.
It is not a debit card. You accumulate a bill that closes at the end of the month (28th?) and is carried interest free until the end of the following month. I opened my card in mid-August. It will generate a statement on 30 August. I must pay by 30 September to avoid interest charges.
Credit Line Sizing
Apple set my credit limit at about 10% of my yearly income based on the number I gave them (about twice my Social Security). It appears to be all about Goldman’s opinion about your income statement accuracy and what they can learn about you from the credit bureaus. Spousal income is not considered.
Apple Touch or Face ID controls access
To use Apple Wallet and Apple Card, you must have an unlocked iPhone with you. Apple Touch, Face ID, and iCloud credentials control access to the Apple Card credentials used for transactions. The secure enclave in the T2 chip stores the Apple Card credentials.
Old School Transactions
On Friday, I ordered some music from Qobuz. I payed for it with my Apple Card by using the card number, expiration date, and CCV obtained from Apple Wallet. These are generated uniquely for each card. At any time, you can request a replacement trio, well just because. Or if you don’t trust the Russian Internet merchant. Those numbers are good until you say they are not and replace them.
Wallet is Really Useful
Image courtesy of Apple, Inc for use in this commentary.
Apple Wallet App gives you access to your transaction history as it is built up, your balance, payment date, and payment process. Click the Pay thing and run through the dialog. You will also receive transaction alerts.
Paying your Apple Card Bill
You pay your Apple Card bill using Apple Wallet to manually initiate an ACH transaction to transfer money from your bank account to your Apple Card account. This requires having your ACH credentials stored in Wallet which keeps them in the secure enclave on the T2 chip.
Apple Card Doesn’t Play Nicely with Personal Finance Programs
Apple Card is not designed to be used with personal finance programs such as Quicken, Mint, and Banktivity. Basically, Goldman Sachs does not offer a net portal for the purpose. Also, the card has multiple account numbers, one for each transaction environment. Only the least used card not present number is exposed for your use. The physical card number and device card number are hidden.
Apple Wallet provides a mechanism for exporting the transactions listed n a statement (they’re in your wallet) to an external computer for transfer to a personal finance manager. Reference [11] gives the export procedures. The import procedure is destination specific.
Fraudulent Transactions
Apple Card is still vulnerable to fraudulent transactions. So far, most have happened when the online card not present numbers were used and leaked by a compromised website.
Other fraudulent transactions have occurred when the EMV chip and pin interface was shimmed in a terminal and the transaction copied and used to construct a fraudulent magnetic stripe card.
Apple Card wisely uses three credit card numbers, one for card not present transactions, one for EMV transactions, and one for NFC transactions. Apple Wallet allows you to lock the apple card physical card disabling EMV and stripe transactions. You can continue to make NFC transactions using Apple Wallet and Apple Watch.
Card Not Present Number Compromised
If your card not present virtual card number has been compromised, you can kill it immediately from within Wallet by requesting a new one.
Physical Card Number Compromised
If the physical card number has been compromised, immediately lock the physical card using the lock procedure in Apple Wallet. Order a replacement card by card by running the lost or stolen procedure within Apple Wallet. You will still be able to use Apple Pay which uses the device card number.
Device Card Number Compromised
This should never happen. Apple Pay uses transaction tokenization and stores transactions locally on the secure element (T2 Chip). Report this to Apple Support! Yell really loudly. I can find no mention of a compromised Apple Pay device number.
Transaction Costs
In the US, most merchants absorb the merchant services costs. Vending machines selling candy and soda are the notable exception. Each transaction has three components, the fixed transaction charge, typically $0.25 for US providers, an interchange fee of 2% to 3% of ticket that has an interchange component and a merchant service component.
Some merchant services providers use tranches for transaction pricing with A, B, and C originators. The pricing bins are for card present, card not present, and risky business transactions. For some reason, lodging charges are risky (reservation deposits and cancellations gum up the works). Restaurants are also risky. Risky is risky in regard to the merchant services provider getting paid. Restaurants are risky because they have a short half-life. Non-profits are typically given preferred rates as little goes wrong for their merchant services provider.
More enlightened merchant services providers offer interchange plus pricing. They pass through the Authorize.net or other interchange network charge adding a surcharge proportional to the ticket face value. For a small non-profit, many merchant services providers will offer interchange plus pricing that averages out about 2.9% of ticket. If interchange plus pricing is available, that is the preferred pricing.
Shimming
Shimming is the new skimming. You can protect yourself from shimming attacks by using the terminals NFC payment interface where ever possible. Shimming has the ability to compromise your Apple Card physical card number.
Crooks sandwich a shim between the card and the terminal. The terminal and card chat for the EMV transaction. The shim snoops on the exchange and stores the messages in flash. The shim can be inserted in the terminal and concealed. If you feel any unusual resistance inserting your card into the reader there may be a shim present.
From what the shim overhears, an unscrupulous person can recreate the contents of an old-fashioned card stripe and make a fraudulent card. This is a risk when your card disappears during the transaction and is then returned. A reputable establishment will perform the card transaction in your presence using a regular chip and pin reader.
It is possible to tamer with chip and pin readers but this is becoming increasingly hard as equipment becomes more tamper resistant to fraudulent setup alteration.
The featured image shows the status of my Virginia 2020 fall election ballot request. The elections office has received and approved my request and it is queued for the mail. As always, there is more. After the break, I’ll show you how to track your absentee ballot through the process using the Virginia Elections Office Citizen Portal.
Former racing greyhounds come with adult size if not with adult brains. They come knowing what they need to make it through work day life. Freedom is a new thing for them. After the initial few days that it takes to realize that this is not Florida and that there is a whole lot of opportunity and a slew of stuff to learn, you can begin teaching them what they need to know.
The first lesson is to look to you for guidance. As they absorb that one, you can begin to teach them the other things they need to know. Like when it is meal time, that your meal is not theirs, that they remain calm while meals are prepared and served, that other dog’s meal is not theirs, to take treats calmly and that other dog’s treats are not to be intercepted. We don’t quite have meal time down but, the remaining meal time and treat time house manners are coming nicely.
Rocky is continuing to mellow and settle in. As he becomes secure in the Dismal Manor Way, he is becoming gentler and more patient but he remains an early riser and won’t settle until his belly has been filled.
The first thing I tried was to divide his meals to feed him more frequently, and to give him a bedtime snack. That didn’t work. He got shouty more often rather than less often. So we went back to the recommended 2 meals per day, morning and evening.
I’ve never raised a puppy before but in some ways Rocky is a big overgrown puppy. I have to teach him things he would have learned gradually while growing up in a home environment. Things he did not need to learn to live in a racing kennel.
I’ve used Retired-Moocher-Dave.org for the blog since I retired. After using the Dismal Manor story on Twitter for a couple of years, I decided to rebrand the blog to be consistent with the dog’s Twitter presence. So I registered DismalManorDispatches.blog and changed from the 2014 theme to the 2020 theme which works better with the new WordPress block editor and has a cleaner layout on phones, tablets, and large and small home displays.
The blog remains under the management of Retired Moocher Dave, alias, The Dismal Wizard. We call our corner of the 757 the Dismal Regions and our residence is variously Camp Dismal in the summer or Dismal Manor in the winter and during hurricanes and thunderstorms.
The 2020 legislature changed Virginia voting laws to permit general voting by mail and to remove the ballot witnessing requirement. These changes allow anyone to vote by mail in any Virginia election without a note from their mother.
Exercising your franchise is important to the vitality of US, Virginia, and Norfolk City polity. I have attempted to summarize Virginia policy and procedures for voter registration and absentee balloting. Please read the linked pages and use the links for all voting-related activities. The display text and link text are identical. Please confirm this by looking at the link target display in your browser, typically appearing in the window footer.
Reference [5], the citizen portal, is where you register and verify that your ballot was received and accepted. The other links give background information.
Reference [7] shows a typical locality Elections Office website. There, your general registrar will give information unique to the locale, especially local ballot questions and office citizen procedures and hours.
As of this writing (8 August 2020) I am unable to verify if the witness signature is still required on the outer envelope. It is the last bit of Jim Crow remaining in Virginia election procedures. I believe the legislature was to remove it in the emergency budget session scheduled for 18 August 2020.
MacOS kernel panic announcement asking if you want to forward the kernel panic dump to Apple.
Image is a screen capture of a screen capture from a blog article linked as Reference 2. Jim thought to catch this standard Apple alert box.
As Apple updates MacOS Catalina, stability appears to be on the decline. Here at Camp Dismal, we are experiencing a number of issues that the Dismal Wizard believed were related to USB disks. This 27 inch Retina iMac has 2, a USB Blue Ray drive from MacSales and a LaCie external disk that had been used for disk backup on our FreeNAS file server.
I’ve been sending crash reports to Apple. I can visualize some summer intern at home up to his armpits in panic reports and hang reports. What is going on? I have no effing idea. After the break, what I have tinkered with to no avail to remove the issue.
A new camper arrived at Camp Dismal (our summer name) a few weeks ago. As you may suspect, Dismal Wizard has some more audio stuff. This time it is a Schiit Audio Modius DAC. Modius is a new “low end” DAC conceived after Jason and Mike had made yet another visit to The Highway 51 Crossroads to find a new DAC and some new output parts. After the break, some impressions of Modius.
Rocky gets powerful hungry over night. When Rocky wants fed, Rocky gets shouty. Painfully shouty if he’s within a foot or two of your ear. So what can we do to get Mr. Fancy Pants to sleep through the night?
Greyhounds for Dummies has plenty about proper feeding but not what to do about a colicky baby wanting fed in the middle of the night at age 4. At least he doesn’t want nursed!
So, brilliant idea, divid his ration in 3 and give 1/3 right before bed. The bedtime feeding prompts a bedtime loo visit. This works pretty well as I have to wait for sinuses to settle after brushing teeth. So I brush up, then feed Rocky. Missy was offered food but it ended up in Rocky so Rocky gets three squares and Missy gets two.
So far, so good. Mixed wakeup times. He’ll ambush me returning from the loo some mornings. Today, he slept in until first light and then some. So we’re calling this change in husbandry a partial success.
Dismal Manor Dispatches 
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