Wadia Digital 121Decoding Computer

Device Type: Digital to Analog Converter/Preamplifier/Headphone Amplifier
Input: AES/EBU with XLR type connector, Coax RCA, Coax BNC, Plastic Optical TOSLINK, USB 2.0
Dimensions: 2.7 x 8 x 8 in., 6.68 x 20.32 x 20.32 cm
Weight: 2.5 lbs. (1.13 kg)
Availability: online and through Authorized Dealers
Price: $1,299.00
Website: www.wadia.com

A Decoding Computer

The 121Decoding Computer is a DAC, preamplifier, and headphone amp. There are inputs for AES/EBU (XLR), S/PDIF (Coax, BNC, and Toslink), and Asynchronous USB all of which are capable of handling 24/192 files. Windows users who have been left behind by Microsoft's decision not to support USB Audio Class 2.0 are taken care of by the Wadia drivers that come on the included USB thumb drive. Mac users just plug in and play.

If we follow our digital signal from the USB output of our computer into the 121Decoding Computer, the first process of note that it hits is the USB Receiver [footnote 1] which is also responsible for the Asynchronous USB technology. This chip then hands off its signal but before it reaches the DAC [footnote 2] its gets to travel through Wadia's Field-Programmable Gate Array (FPGA), along with the non-USB data, which contains 8,256 logic cells (I counted, kidding) for a veritable DSP car wash performing a number of operations including buffering the incoming data into memory, upsampling using Wadia’s proprietary DigiMaster algorithm and filtering technology as well as applying Wadia's ClockLink jitter reduction technology for USB or Wadia's ClockLock jitter reduction for non-USB data. Once your de-jittered, scrubbed, upsampled, smoothed, re-clocked and locked data enters the "D" side of the DAC chip, its upsampled again this time to 32-bit/1.4MHz before the conversion to analog.

We've seen these kinds of heady heights heightened further in the Resonessence Labs Invicta DAC which upsamples all incoming data to the "50MHz domain". Since upsampling in general is still a sometimes controversial (aka misunderstood) subject, I asked John Paul Lizars, Director of Marketing for SUMIKO and my contact for this review, if he could talk about the sonic benefits of the 121's DigiMaster algorithm and filtering technology which preforms the first phase of upsampling. John Paul passed my question along to John Schaffer, Wadia's President, who was kind enough to provide the following answer:

Digital filtering systems are used in most DAC's. They increase the sample rate of the source data so that the analog filter can be implemented in a way so that the filter itself will not introduce audible distortion.

The DigiMaster system in the 121 is a software based solution that runs on a DSP block configured in the FPGA. DigiMaster uses a synchronous interpolation process to preserve the entire original signal and provide a higher data rate. What is unique about DigiMaster is that it is a predictive algorithm, it uses Spline math to calculate a curve that will fit between the known data points. Essentially it is attempting to rebuild the original wave form in a way consistent with how we understand wave propagation. With the 121 we are able to achieve 32 bit precision in the calculation used to derive the predictive sample points. That allows us to calculate the predicted sample without requiring intermediate rounding, or truncation, steps in the calculation of the new sample. The improved precision results in an audible sonic improvement. The DigiMaster system provides balanced performance, producing excellent results in a wide range of tests, including phase and impulse response, which are critical to accurate and realistic reproduction of music. The sound of our solution as implemented in the 121 we feel is very natural and provides a heightened sense of "Being There".

Sticky stickers (I tested) providing ocular isolation from revealing reviewers

Interestingly, Wadia offers up their preferred method of connectivity in the manual as follows (in descending order of performance): USB, AES/EBU using XLR connector, Coaxial cable using BNC connector, Coaxial cable using RCA connector, TOSLINK plastic-optical cable. Most of my listening, which we'll get to soon and see how close to "being there" I was able to get, is based on the USB output of my MacBook Pro running Pure Music and Audirvana Plus.

The 121Decoding Computer's volume is controlled in the digital domain in "(120) 0.5dB steps" for a 60dB range (I know you already figured that out but I thought I'd save you the trouble). There are six blue LEDs on the 121's front panel that give you a ballpark display of your volume level (you couldn't very well have 120 LEDs). Since I use an integrated amplifier, the Leben CS-300XS, I mostly kept the 121's volume pegged at its max level except when using the headphone output.

Owners can also adjust the output voltage level by choosing 4.0v, 2.0v, and 1.0v to match their system's sensitivity. Three of those same six LEDs used to show volume level also indicate output voltage level when you are making adjustments to it with the included remote. Those same LEDs also serve triple time as balance indicators when adjusting left-right balance with that same remote. Since the 121 does not include any controls on its chassis, you'll want to Velcro that puppy to something that you never lose. Our dog Heidi volunteered but that seemed all wrong so I just followed my two-place rule—only put that remote in one of two places.

USB thumb drive w/Windows drivers, Wadia remote, and external switching power supply

But doesn't digital volume mess with the bits making them less than perfect? Wadia explains their use of digital volume control in the 121 manual as follows:

Other functions offered via remote include input selection, mute, phase (the 121 inverts absolute phase in the digital domain), headphone output sensitivity (low and high), and display brightness (two settings - really bright or not quite as bright). The basic replay function buttons (play, pause, stop, next/back, and eject) work when using a matching Wadia CD transport for those old-school disc types. To fill out our functional picture, the 121's face also includes six LEDs indicating the source selection and six more that indicate the incoming sample rate (44.1, 48, 96, 176.4, 192kHz).

Early production 121 units included two headphone jacks, 1/8" and 1/4" (as I write this the Music Direct website is still showing this version) but that 1/8" jack was replaced with a power indicator LED. The reason for this change from 1/8" headphone jack to always-on blue LED was also explained by John Schaffer of Wadia:

As it turns out, not all 1/8 " headphone plugs are the same. We learned that if the barrel of the plug was molded a certain way then the plug would not seat properly into the jack. A customer might experience an intermittent connection when using their headphones with the 1/8" headphone output on the 121. Consequently we made the decision to remove the 1/8" headphone jack in order to ensure that we would not create a less than positive experience for any customer.
I'll have to rib Wadia for this decision to replace that 1/8" jack with a power indicating LED since you cannot turn the 121Decoding Computer off without unplugging it. Which kind of relegates that LED to permanent no kidding status (I swear I think it winked at me once or twice) especially seeing as the volume level LEDs also stay lit. That's correct, there is no on/off switch to be found on the 121 and Wadia explains that the 121 sounds better when left on. Thermal stability is their explanation for this phenomena and Wadia offers this additional powerful advice in the 121 manual, "A new unit will undergo more dramatic changes when power is applied for the first time. If you turn off your Wadia 121Decoding Computer for more than an hour, you will find that the unit will undergo a similar, but less dramatic improvement once power is reapplied."

I find the look and feel of the 121 and the included aluminum IR remote to be solid and reassuringly well-made even considering the 121's near-feather weight. And the main reason its so lite is because Wadia uses an external switching power supply in the 121Decoding Computer. Gasp! Upgrade! The horror! I did not try any after-market power supply upgrades with the Wadia 121 mainly because I didn't feel the need to and to my mind things like power cord swapping and power supply 'upgrades' are largely system setting dependent. But this certainly puts the no power switch decision into finer focus.

Trickle Down Works
Even though the 121Decoding Computer is the relative babe in Wadia's line of decoding computers, it performs like its all grown up. This is another instance where I pretty much fell under the 121's spell from the first few sweet notes it sang. The 121 passed every test I threw at it with flying colors including the did-I-sing-along test (yes), the did-I-feel-sad test (yes), the ever-embarrassing to admit did-I-dance test (yes), and the most important of all the did-I-play test (Oh yea). And I would not highlight a particular aspect of the 121's sound for all of this testing success as it strikes me as exceedingly well-balanced.

I'm going to break a few of my unwritten rules in one shot and share that there's a CD/rip I use repeatedly as a test track and have for years. There I said it. Actually there are many of these but this particular one is odd in that I only really enjoy listening to this one track. The rest of the CD leaves me with a touch of saccharine-overdose. Even this one track, Percy Grainger's arrangement of Ravel's "La Vallee des cloches" from In A Nutshell [EMI 7243 5 56412 2 9] has its ups and downs. But overall, I find it to be a lovely piece/place and the bells in the title ring out in all manner of voice, shape, and size and are even laid out in space (as in a valley). This song's presentation can suffer any number of digital deaths including ring-castration, edge enhancement, foreshortening, timbral sameness and on and on. The 121 threw everything encoded in the associated bits of "La Vallee des cloches" out into my listening room making it feel at once vast and imbued with, wet with, emotion. Stunning, really.

This ability to turn test track into emotional experience is ideally what I want from every piece of hi-fi. If I stick and stay stuck in test mode something is wrong. In terms of methodology, I listen over weeks and if possible longer for many hours each day to help avoid the variances and fluctuations within me and my listening moods. Kinda like a switching power supply, I like to leave my listening on over extended periods. And the 121 never disappointed, never revealed a sonic edge that stuck out to distract me from listening for pleasure. I was never jerked back into test mode (I hate when that happens). To put it as simply as possible, the 121Decoding Computer makes digital files sound like sweet, natural music and that is a conversion process to write home about.

Some of you may be wondering about the 121's bass response since there's this notion that a piece of hi-fi gear has to have some size and heft to it in order to reproduce bass convincingly = big power supplies, big iron. The tuba theory. Did you ever notice in those wonderful old doo-wop groups that the dude handling the deepest nearly inhuman-sounding subterranean notes was typically rail-thin? Rest assured the 121 can plumb the depths even without an anaconda-proportioned power cord and what's more bass is controlled, dimensional and presented as part of the whole. This is also partly responsible for the 121's dynamic snap appeal. Nothing lags or gets bloated or slow. Music moves.

I also took the headphone output of the 121 for a spin with my Audio-Technica ATH-W1000s and when music was not playing things were silent (as expected) and depending on the musical selection things were more and less silent (as expected). I have to admit my preference for listening in-room and part of the 121's strengths is how convincingly it presents music in-room which is to say its physical, solid if a tad tightly packed and missing an iota of air among and around musicians (where this kind of thing exists), and dare I say muscular.

A Musical Contender
To my way of listening, the Wadia 121Decoding Computer jumps right onto my short list of recommended components. It strikes me as being at once refined yet not overly resolute, with a voice that sounds like music. Sweet music. I enjoyed every listening minute spent regardless of the recording or its associated quality. That said, well-recorded music can be especially stunning through the 121 so whether you like to stroll through the valley of the bells, swing with Ella and Louis, sway with Bob Marley and the Wailers, sing along with Tom Waits (as bad as me), sink into a sweet sullen state with Schubert, Sinatra or Syd Barrett, or raze the roof with Einstürzende Neubauten or John Lee Hooker, the Wadia 121Decoding Computer may very well have your ticket to ride.

Footnote 1. If you search around the internet you'll find references to (and a video of the insides of the 121 without the stickers from a Wadia dealer) the manufacturer of the USB Receiver chip used in the Wadia 121. One dealer claims this USB receiver chip is from XMOS and while this seems likely I could not get verification from Wadia who'd I imagine feels this level of detail is practically irrelevant. And for most intents and purposes I'd have to agree. The notable exception being reverse engineers (and good luck with that).

Footnote 2. The DAC chip used in the 121 is reported to be from the SABRE32 Reference line. This information also comes via a dealer comment on a forum so you can take it for what its worth. See footnote 1 for more.

Associated Equipment

Also on hand and in use during the Audiophile Desktop review: Mytek Stereo192-DSD DAC, Schiit Bitfrost DAC, AudioQuest DragonFly USB DAC.

Pablo's picture

Looks like a nice unit but why didn't you compare with the other dacs you had "on hand", that would provide a much more insightful review specially for those who have them.

Oh and when are you going to review the so long awaited Mytek 192 DSD ?


Michael Lavorgna's picture

If you've noticed, I do not typically include comparisons mainly because I find them to be irrelevant. I may say more on this at some point in time but this notion that comparative differences add value to a review is something I do not necessarily agree with.


Sooner than later.

Jitterjabber's picture


I was curious about Wadia's manufacturing. Are the 121'a designed and made in the USA? I only ask because the price seems more affordable than I would expect-based on Wadia's legacy products.

I would be interested to know how the Wadia 121 sounded next to the Benchmark DAC-1.

This would be a valuable comparison considering the price point is nearly identical. Yes they use different upsampling methods, but this is what I would like to compare. The power supply on the DAC-1 was very carefully deisgned,but the switching power supply of the Wadia is DC power, think Empirical Audio. 

Gosh, I imagine these kind of comparisons are hard to publish, but would be very worthwhile.


Michael Lavorgna's picture

is "Designed and Assembled" in USA according to the sticker on the bottom of the unit.


This is one of the issues with comparisons - the number of relevant ones is nearly equal to the number of people interested in one.

btw - I do not have the Benchmark DAC-1


As I said, I have my doubts as to the usefulness of comparisons for a number of reasons but they are too involved to get into here.

Jitterjabber's picture

I've tested DACs - including Benchmark, Crane Song, Antelope, and Lavry - the progression of this technology is very interesting.

Each manufacturer approaches it a little differently.

I am not listening to a DAC for "a" sound. but rather listening for the decay of reverb tails, evenness in frequency response, impact, low level resolution, stereo separation, and localization of sound sources. I expect the DAC to translate all the sonic information of the recording. Example: If a recording artist uses a tape machine or tube electronics for the recording, I want to be able to hear that through the DAC.

Having used various DACs, and clocks (yes, very accurate ones) - I can certainly say that obvious differences exist if you use your ears. Audiophiles often look for a certain sound for a specific system they are setting up. A DAC should never be a color source. Rather, use a tube pre amp if you want added harmonic color, or choose an amp that sounds musically satisfying to you. Seriously.

Expressing how well various DACs actually/truthfully reproduce music in the analog domain is important to share. I educate my young friends about these differences, and they are more interested in HiFi because they feel like they can understand and hear what I am talking about. I guess most of my friends are nerds like me, and most people just want a simple answer.

I have friends who are designers, and work with engineering, and the arts. They all really enjoy the "experience" of life. This includes visual and sonic intricacies.

That being said..I think your reviews are excellent and very detailed.

this is for audiophiles, right? or is the AudioStream demographic larger?


Michael Lavorgna's picture

You raise a number of interesting issues and I’ll address a few.

A number of years ago I was in a Hi-Fi store. Two guys came in to audition speakers and they used a CD-R they’d brought. It turned out one of them was the mastering engineer for this recording and the other one of the performers. They compared two speakers and the engineer preferred one and the performer the other.

From my way of thinking, the best hi-fi is the one that is used and enjoyed most often. And in my experience this has nothing to with anything you’ve mentioned here.

If you were to round up 25 of the staunchest objectivist audiophiles you could find, compared their hi-fi’s, and discovered they all owned the exact same equipment from end to end including the cables, I may begin to see the relevance of the objectivist approach to hi-fi.


“Computer Audio For Everyone” Is what it says directly under AudioStream. That said, I’d say the site if for anyone who is interested in the quality of the experience of listening to music on the hi-fi.

And in my experience, the term audiophile is about as useful as the term biped when trying to gauge someone's interest in hi-fi and music.

Pablo's picture

I fail to see how direct comparisinons are irrevelent. Techincal info aside one could copy past the review to a great number of dacs and wouldn't feel out of place.

For me and my hi.fi enthusiastic friends that's when a review really offer some real insight because there we can have a common ground if we already listened to said piece and where we can understand the improvements and downfalls. Without them we are stuck with the "it sounds nice" but compared to what? 

So could you explain your view  as I'm obciously missing?

Michael Lavorgna's picture


This is an excellent point. I try to be careful about what I say and how I say it within the context of what I’ve said in other reviews. So from my point of view, you couldn’t cut and paste this review into “a great number of dacs” that I’ve reviewed.


The best example I can give in this instance is if I had compared the Wadia DAC to something you and your friends have never heard. I get a lot of emails asking me to compare one DAC to another and there is no rhyme or reason to these comparisons other than what the person sending the email is interested in.

Jitterjabber's picture

I agree, that individuals have preferences. I just consider a DAC a source. It is just my opinion - i don't look for colored sources. But, if you are interested in messing with the original signal before it even gets amplified, have at it.

Mastering engineers will surely have a different opinions on neutral..ha... I've used the full range Lipinski speakers, Dunlavy, and others. They sounded fantastic, but too neutral for most "audio enthusiasts."

I agree about the term "Audiophile." In fact, I only use it when refering to old school hifi enthusiasts...hahaha. 

nobody I know uses the exact same equipment, but they all use similar technologies (i.e. DACs with upsampling and jitter reduction) So, in short, yes comparing these similarly priced DACs would be beneficial to customers. My friends use the HiFi everyday, but doesn't this market depend on people upgrading?

wish it could happen,


Michael Lavorgna's picture


You seem to move between ideas and realities and perhaps you are confusing the two. First off, the notion of “colored” versus not-colored is your paradigm, not mine. I think you’ll agree that there’s no such thing as the perfect uncolored source that will suit everyone. In reality, DACs, Media Players (Pure Music, Amarra, Audirvana, J River…._), turntables, disc players, all deviate from perfection to a degree. So we can have two DACs that measure very well yet sound different. And this difference and someone’s preference for one over another is for me the more pertinent and interesting reality.


I suppose it has become a common form of discussion to present your own dichotomy and then assume since someone does not agree with it to throw them into your self-defined lessor category. I have not said I’m interested in “messing with the original signal” but seeing as you are familiar with the recording and mastering process, I’d assume you’d agree that some sources are better than others. So someone who listens to mostly 16/44.1 source material versus someone who listens to mostly HD source material have different requirements in terms of a DAC, for one example.

… but doesn't this market depend on people upgrading?

This is not something that concerns me.

Jitterjabber's picture

From what I read, and what other people post on their own blogs indicates that people do want comparisons.

We audio enthusiasts love listening to improvements and differences in sound reproduction. Pure music lovers will not care as much, but I thought that (based on the gear you review) audio HiFi enthusiasts would really enjoy understanding the sonic differences b/t DACs.

Maybe this is not the place for that,


Michael Lavorgna's picture


My experience suggests that comparative listening often confuses difference with improvement. This is why I stress the importance of listening over time and why I also often talk about the importance of listening for yourself.


My point with comparisons is they need to be relevant and not provided simply for the sake of noting difference.

How many DACs are there? And how would you determine what a relevant comparison is? Here's a list right off the top of my head of the most popular kinds of comparisons:

1. What I happen to have here at the moment comparison
2. Compared to my Reference comparison
3. Like-priced unit comparison
4. Similar technology (e.g. same DAC chip) regardless of price comparison
5. What a reader owns compared to what I review comparison
6. The Giant-Killer comparison
7. Similar functionality comparison (e.g. DAC/Preamps comparison or USB DAC comparison)
8. The Big RoundUp comparison by price, technology, functionality...
9. The most popular in their class comparison
10. The recommended component comparison
11. The budget component comparison
12. The Cost-No-Object comparison
13. The Digital to Analog comparison

Do you have a favorite?

Maybe this is not the place for that

May be.

Jitterjabber's picture

I'm investigating other possible ways to examine DAC differences.

Thanks for your review. 



Stephen Scharf's picture


Good review on the Wadia 121. You've describe the attributes of the 121 accurately. One thing I would take exception to is your comment, "...if a tad tightly packed and missing an iota of air among and around musicians...."

Give the Wadia another month or so of run-in and see what you think. I've had mine for almost three months now, and I think that the Wadia is pretty exceptional in this regard.

Michael Lavorgna's picture

Another issue for reviews is time. The Wadia is already packed up and ready for return.

deckeda's picture

Long version:

Comparison reviews eventually made me cranky. I understand the desire. I've usually wanted the comparisons. This month, Best. Next month, New Shiny=Best. Wait, improvements come that quickly to audio? With seeming regularity?

Car reviews, camera reviews and more are almost all like this.

I'd much rather read a descriptive experience that attempts to talk in a holistic manner, not an absolute expression that might be stale (and irrelevant) when the next competitor comes around.

When I first began reading reviews years ago I always thought "audition it for yourself" was the biggest copout --- here these guys were, with equipment, rooms, music and experience I could likely NEVER attain, and "therefore" more qualified to simply and reliably prescribe.

Yeah I don't think that way anymore.

That said, if a reviewer notices a distinct possibility that last month's darling is still better/has "become worse" relative to the New Shiny please let us know. Everyone wants a shortcut to the buying process when possible. Even if they really should still audition at home.

Short version:

Thanks again ML for stating a clear philosophy clearly.


Sticky Stickers=Provenance Protectors!

Advice to buyers:

After you buy an item, stop shopping ... and for a minimum of 6 months. I've heard that sane people actually wait longer.

Michael Lavorgna's picture

And thank you for sharing your long version.

Frank's picture

Interesting approach in handling all of the comparison banter - good on you for not giving in. 

It appreared pretty clear and apparent to me that Mr. Lavorgna liked what the Wadia was presenting to him in his review as he clearly stated "the 121 never disappointed, never revealed a sonic edge that stuck out to distract me from listening for pleasure".

If that is not validation of a postitive review, then I truly missed something.

attilahun's picture

Thanks for a great review.

I love the idea of getting Wadia tech at a more reasonable price. 

Computer time has eclipsed my big rig time and I'm anxious to upgrade my USB dac. 

The 121 has a great feature set and is a prime candidate for me. 


newby11's picture

After belatedly reading ML’s review and then JI’s review of the NAD M51 dac/pre, I must also register my disappointment, though on slightly different grounds than expressed here already. As a consumer, it appears to me that we are in the midst of a possibly revolutionary change in fundamental system architecture as digital audio continues its rapid evolution. The familiar source>preamp>amp(s) paradigm is being challenged with products like the Wadia and NAD that argue for a server/source>dac/pre>amp (or even just a 1-box dac/pre/amp) set-up. (For us moderately engaged audiophiles, it seems to me that the Benchmark dac/pre was a watershed moment.)

A while back I read (in a competing rag) a review of the Marantz 7005 pre/pro and Parasound multichannel preamp as 2-ch preamps, in a SOTA stereo system.  The conclusion was that both gave up some very small ground to SOTA 2-ch preamps, but overall both were very close in overall performance in terms of musical realism and enjoyment. Given the affordable prices and the built-in ability to incorporate into a single HT/music system (stereo or multich), these immediately went onto my radar and challenged my notion that I’d need 2 separate systems.  Fast forward:  Lo and behold, I notice JI’s reference system uses a…Marantz 7005 multichannel pre/pro (pure direct mode) as the stereo preamp. 

Here’s the crux of my argument:  We’ve all learned that today’s best reasonably priced DACs represent major advances in musical realism at prices a fraction of what similar quality would have cost even 5 years ago.  If building a system from scratch and budget matters, then the latest crop of dac/preamps could represent a major shift in system architecture iff their preamp functions were similarly advanced (i.e., save on preamp and interconnects). Yet both ML and JI (and others) completely ignored the preamp function in their reviews!

My plea:  Please do a follow-up (ML? EL? JI?) with the Wadia and NAD and comment on their sound as DACs vs. as DAC+Preamps, which can then give some context to whether the no-preamp-needed paradigm is ready for audiophile primetime.  Further, it would be good editorial practice to not ignore included preamp functions in future reviews. This is of burning interest to me and anyone else on a budget—particularly those of us building out systems in this new all-digital golden age. (Sorry, I don’t own a single vinyl record).

Michael Lavorgna's picture

The Wadia 121 offers several digital inputs and a digital volume control and I've seen them refer to it as a "digital" preamp which makes sense. So while it obviously does not take the place of a traditional analog preamp, for those who only need digital inputs, it can fit the bill.

The practical aspect of your question boils down to - does the digital volume control of the 121 degrade the sound and my answer is no when used within its recommended range. Here's what Wadia suggests in the manual:

Best performance is obtained when operating the Wadia 121Decoding Computer Volume Control near the top of its range. If needed, the maximum output level of your Wadia 121Decoding Computer can be adjusted to match the overall sensitivity of your system so that critical listening will take place with the volume control operating near the top of its range. Critical listening should be done when the 4th or higher LED is lit.

Unfortunately the Wadia is shipping out today so a follow up is not possible.

Frank's picture

I would say generally speaking, audio reviews are pretty subjective and rely more on style of the reviewer rather than a particular process or a specific checklist that might help one to compare a product to other similar products.

It could well be that audio gear has so many variables that it is hard to do this.  With the addition or subtraction of connective cables, relying on other associated gear, speakers and so on, it could be a rather daunting testing process and maybe this is the reason why Consumer Reports does not test high end audio gear.

At the same time, maybe this opens the door for a reviewer to set up a more orderly way to review gear where it is less subjective and more objective, but I am not sure there is enough in it for the review writer to even begin to compile and compose such a standardized method of review.

My process in reading audio reviews has always been to try and get to know your reviewer and glean what I think is their personality in the reivew and how that relates to what one takes away from it.  At the end of the day a review is only as good as the reader interperting what the reviewer has written or in some cases seemingly left out, but that is about expectation and not about what is actually missing.