Derkoli

Not sure where you get this idea - there is nothing wrong with using an audio interface as a DAC. In fact, some of them have really, really good DACs in them. The line outs in the RME ADI-2 are good enough to push the limits of modern audio analyzers. 
 
Also, the chip used is only one small piece of the puzzle. A good implementation of an AK4490 is far better than a bad AK4499 implementation. Furthermore, since AKM still hasn't gotten their act together, you may be looking at hardware using TI, AD, ESS or Cirrus Logic chips in it.
 
The Scarlett 2i2 has a very good DAC in it. I measured the line outs on mine to have a THD+N of about 0.0007%. While there are certainly more linear DACs out there, the differences won't be very audible.  The MOTU M2 performs a tiny bit better but seems to be pretty difficult to find.
 
I'm generally quite happy with the Scarlett. It's about as good as anything in that price range. The headphone amp in it is pretty weak (distortion and output impedance are fine, but it's pretty limited in power), and I'd like to see a bit more gain in the mic preamp, but the converters and USB interface in it are solid.
 
Since most audio interfaces have mediocre mic preamps, spend the extra $100 or $150 and get a decent headphone amp to go with it. I quite like the way Schiit designs their headphone amps. The newer Magni amps are linear enough and powerful enough to be more or less transparent. I don't care for how they design their tube amps though - I'd look elsewhere for tube gear.
 
 

They even tell you it's a scam.
 
If you're still not sure, I have a bridge in London I'd like to sell to you.

Are you really suggesting someone spend money on boutique film caps for a sub-$1k speaker? Really? 
 
Even in a $10,000 speaker build, I would call those caps a complete waste of money. At this price? You're spending more on capacitors than on the speakers themselves, when those caps make zero improvement over a generic polypropylene of the same value in this application.
 

Some people seem to miss the point of measurements.
 
The point of measurements is reducing expensive and very time consuming trial-and-error. Whether your preferences are for objectively ideal equipment (flat FR, low distortion, etc) or some other variation isn't really relevant here - the measurements are useful either way.
 
For example, if you know that you really like the characteristics of the Yamaha NS-10 (hint: not for pleasure listening), a careful look at the Yamaha NS-10 frequency response and distortion characteristics can give one a pretty good idea of why they sound the way they do. This can then be used to identify other speakers that may be good candidates for demo. Yes, this does require a bit more of an understanding of how audio equipment works, but it's a much more practical way to buy speakers, especially as it gets increasingly difficult to find places where one can hear a system before making  a purchase.
 
The value of measurements when it comes to amplifiers is a little different, and it's mostly for weeding out equipment with issues. Class AB amplifiers with bias issues (and bias drift issues!), tube amps with unacceptable noise floors, amplifiers that can't actually meet their power specs (this seems to be increasingly common in consumer spaces), class D amplifiers with strong load dependence, crosstalk issues, etc. These are all things that are nearly impossible to glean from a listening test. Something may not sound right (or may not sound right under certain circumstances), but quantifying exactly what's going on is really difficult. 
 
 

I've refined my system down to;
 
Chord DAVE -> McIntosh C53 -> McIntosh MEN220 -> McIntosh MC1.25kW -> MBL 101 x-treme
 
Each of the speakers has a powered sub to go along with it, hence the MEN220 for a crossover. The mid/high towers are passive.
 
Just to add on;
 
If I'm only just sat at my computer watching youtube, I feed a pair of JBL LSR308 MkII's with a Behringer Xenyx1204 USB, which is in turn fed with an SSL 2+ interface.

Obviously, everyone who can hear cares about audio quality. Everyone has a threshold where, below a certain quality level, they'll return a product. The difference between the average consumer and an audiophile is the degree to which they care.
 
What are you trying to ask about?

I haven't read that part of the proposal but let's say that "professional use" is exempt from this law.
So what? Apple might argue that the iPhone is a device for "professional use", but they are not the ones ruling whether or not it is. An EU court is. It's not enough that Apple just says "we don't have to follow this law because X", a court has to agree with them.

Generally it's better to oversize an amplifier than it is to undersize an amplifier. It's much easier to damage a speaker with distorted power from a small amp than it is with clean power from a big amp.
 
I estimate the speakers I use in my office to be about the equivalent of an "80 W" rating (they're my own design). I'm running a Crest 3301 right now (about 450 W into 4 ohms) and for a while I was running an MC1250, which will do almost 1300 W into 4 ohms. Nothing wrong with that, and there are some big amplifiers that sound fantastic (that MC2 and Crest being examples of this).
 
The main issue crops up when you take an undersized amplifier, that isn't rated for 4 ohm loads, then push it really hard into a 4 ohm load. That is asking the amplifier to source more current than it was designed to, which can push the output devices outside their SOA. It's even worse with a heavily reactive load, since that's the worse possible case scenario for output device SOA.
 
 
 
I'd probably ditch the receiver, then drive power amps directly from a DAC or audio interface.

Only if absolutely necessary, and then you spend as much on it as you can afford. The $10 - $20 variant off Amazon is a bad idea. 
 
These are audio transformers, and designing a good audio transformer is neither easy nor cheap. A good one, like those by Jensen will be $50 for just the transformer alone. If it's a Lundahl, double that. Linear, wideband isolation is expensive, no way around it. I've been searching for an economical way to do linear isolation with good bandwidth for years, and so far have turned up nothing. Cheap transformers aren't very linear, and even the expensive ones aren't as ideal as one might hope. Isolation amps aren't great either, and you'll pay through the nose for them.
 
Really cheap transformers will tend to create a lot of low frequency distortion, and in some cases a fair bit of HF attenuation (and definitely HF phase shift). That low frequency distortion can be a good thing (think Neve 1073), but this isn't where you want that.

My stance is that unless you plan to shell out the money to do it properly, don't isolate. Most of the time, you can go unbalanced to balanced without any significant issues. If you look at the schematics for a balanced input on things like those monitors, tying pin 3 to pin 1 basically turns it into an unbalanced input. It's still noisier than an ideal unbalanced input due to the thermal noise from a couple additional resistors, but this is of no consequence in any well-designed gear. 
 
 
The answer is you start with none, and only add them if you absolutely need to. They are a problem solver, but unless you spend a good $200 - $300 on them, they'll come at a performance cost.

Really not the case. I don't have any strong preference here. While I've heard the T5V, I don't own any active monitors in this price range. I thought the T5V was voiced bright, but with an HF shelf it was pretty tolerable. I really have no opinions on the Mackies. The brand preferences I do have are all way outside the OP's budget, so they don't factor in.
 
 
I do, however, take issue with people posting bad measurement data and using it as a point of argument. 

That FR plot is garbage. Notice how both speakers have the same bizarre characteristics? That's a measurement issue. Given where the garbage is, it's almost certainly a room issue.
 

I read frequency response plots on a pretty regular basis. There is, in fact, an industry-standard test environment, and that's an anechoic chamber. Alternatively, there's the Klippel system that mathematically compensates for the room the speaker is being measured in. There are a few online reviewers who have them, and Klippel does measure loudspeakers for a fairly reasonable price ($100 IIRC).
 
There are also ways to get a quasi-anechoic response using DIY measurements. I'm not going to go into too much detail on this, mostly because there are several really good online resources on the subject. 
 
Yes, the sort of data you posted is common - because there's a lot of garbage speaker data out there. The data you posted tells us almost nothing about the two speakers, other than that their characteristics aren't grossly different. The effects of the room are a good 10 dB larger than the differences between the speakers.
 
Essentially, because the room effects are so large, the scaled needs to be a ridiculously coarse 10 dB/div, by which point it's difficult to see the effects of the speakers themselves.
 
 

Just nab a pair of Adam T5V's.

Just nab a pair of Adam T5V's.

Most vinyl has a bandwidth of about 18kHz. Fresh, quality-pressed vinyl also has a dynamic range of about 70dB, which equates to roughly 12 bits. Thereby, there's scientifically no point in archiving above 44.1/16 unless you're using an insane amount of post-processing, in which case 24 bits might suffice.
 
This is an unpopular opinion (despite being accurate) but people who store lossy formats like vinyl in high sample rate / high bit-depth lossless digital containers are a bit goofy.

Did absolutely nothing.  No change in the noise in dB or subjective profile.
 

 
-20dB change in the noise floor.  -70dB is mostly inaudible without having the gain cranked to absurdly loud levels.  The sound profile is still buzz-y (maybe 60Hz hum?) but it lost a lot of the "data" fluctuation sounds and is a lot more consistent.
 

 
Basically completely fixes the noise.  I can split hairs and say that -84dB isn't complete silence but I barely hear it with the gain maxed out and have to have my ear next to the speaker.
 
With a Monoprice USB power adapter providing external power (there's a switch on it to change internal vs. external power)...no difference it is still -84dB.
 

 
This only does anything when it has external power, it changes the hum to a slightly higher pitch than the "Compact Hum Eliminator" and similarly filters out the data fluctuation sounds.  This thing cost like $60 though sooooo.....nope.
 

 
OK what if you completely change to a different USB interface?  Well...exact same noise outcome of -50dB, same sound profile.
 
Conclusion:
 
Nobsound really won this thing.  I don't what it's doing but whatever it is by far worked the best at cleaning up the sound.  And for only $25 which is cheap compared to a lot of the other "solutions".  I'm not going to sit here and say it'll fix every audio issue because god only knows how many things can create noise in an audio path, but  at least from what I observe it really cleaned up USB based noise.

That shouldn't destroy speakers.
 
Turning speakers on last is an extremely good idea. You should turn your source on first, then anything between the speakers on, then the speakers. This is extremely common practice and is how you should turn your kit on. Everyone in live events does this, and you should be doing it in your studio.

1: For the best "sounding" I'd go with the Adam T5V if you're using a subwoofer, or Adam T7V if you aren't using one. The tweeters sound incredibly natural and have extremely good transient response.
 
2: See above.
 
3: For the use case, then yes. They are worth it. For the price they have decent low end response, and are very flat.
 
4: No. KRK stuff is notorious for reliability issues, and I personally think other options exist at every single price point that are superior.
 
Given all the factors, I'd go for the Kali LP6. They have good DSP built in (that can compensate for being close to a back wall), are front ported, very flat for the price and have good low end response. In this case, they make the most sense.
 
If you had a subwoofer to use in conjunction with the monitors, I'd look into the Genelec 8010 AP.
 
Eventually, I'd highly recommend investing in Sonarworks, or learning how to use REW. Using a measurement mic and DSP to flatten out your monitors will improve things in essentially all situations.

1: For the best "sounding" I'd go with the Adam T5V if you're using a subwoofer, or Adam T7V if you aren't using one. The tweeters sound incredibly natural and have extremely good transient response.
 
2: See above.
 
3: For the use case, then yes. They are worth it. For the price they have decent low end response, and are very flat.
 
4: No. KRK stuff is notorious for reliability issues, and I personally think other options exist at every single price point that are superior.
 
Given all the factors, I'd go for the Kali LP6. They have good DSP built in (that can compensate for being close to a back wall), are front ported, very flat for the price and have good low end response. In this case, they make the most sense.
 
If you had a subwoofer to use in conjunction with the monitors, I'd look into the Genelec 8010 AP.
 
Eventually, I'd highly recommend investing in Sonarworks, or learning how to use REW. Using a measurement mic and DSP to flatten out your monitors will improve things in essentially all situations.

I went to lttstore.com
 
I laid my eyes on the LTT Case shirt. I legit thought at first glance, that it was a shirt promoting Renault Motors
 
I found that really strange
 
 

Got some new shoes

I can totally understand your view point. I mostly think like this aswell.
 
The vast majority of my clothing is Patagonia. I've only bought this item as it'll fit excellently with an outfit I have in mind. I tried to find something else for cheaper, but this is the exact look I'm going for. The brand hasn't influenced me at all.
 
As much as I don't want to support Amazon, this is fair I think. But I think I prefer to pay 2-3 pounds for each delivery from smaller companies based in the UK. It just makes me feel better.

Part 10495 of switching up my wardrobe.
 

 
7 quid for delivery. Borderline criminal.

imagine paying 350 pounds for a sweater that costs 15 to make...
 
 
whats criminal is that your buying stuff like that, doesnt matter if your rich or your poor, buying something for a word written on it is kinda sad tbh.

Part 10495 of switching up my wardrobe.
 

 
7 quid for delivery. Borderline criminal.