Just about to pull the trigger on Pontus 15th ...

@lanx0003 yeah I understood your question & concerns but I ended up babbling on about my situation. My experience with impedance matching has only been with preamps & amps as far as close calls & definite issues from mismatches. I have a 10k input & a 12k input amps. I've been as close as an 8x's difference between the 2 & didn't notice any meaningful issues. I've had preamps in that 5k range & probably higher depending on frequency where noise & brightness occurs. Stuff like my old PAS preamps caused issues with all my modern day solid state amp. 

I've run my MTK kit preamp which can be as High as 1800ohms sound quite nice with my 10k amp. Not exactly the same situation between dac & preamp though. Maybe someone else will chime in with something similar to your exact question. 

Wow, no apparent issue from 10k to 12k! Maybe I, along with many others, have been overly concerned. But here’s my experience: I used a preamp with a 5k output impedance into an amp with a 20k input impedance, and the sound felt restrained. However, this particular preamp was well received by some, if not the majority. I tend to attribute this to a matching issue.

I had been eyeing Denafrips for a long time, but its high output impedance was always a hurdle that kept me from pulling the trigger. Then the Harmony DAC had the same design—until this micro DAC came along, seemingly designed to address matching concerns. I don’t know. I guess I’ll never know until I try, right?

Yeah my 2 lowest impedance amps are an Arcam PA240 at 10k & a Rotel RB-1582mkii at 12k..this is their single ended inputs. Not an issue with solid state but I favor tube preamps. When I bought the Arcam I was unaware of its input. I had a Arcam SA30 & liked the amplification of it so much when I saw a deal on the PA240 I grabbed it. At the time it was an issue for my favorite preamps & I regretted buying it. It was very disheartening. 

With preamps you can compensate a little by upping the value on the output caps which most tube preamps have. But when the match is really bad it's like you said..less drive/gain. I'd have rolled off bass & hot treble. If the match was really bad it will add noise into the system. Also a lot of times what the manufacturer specs isn't always legit. It could be a 1k output at 1khz with the volume full blast..with the impedance actually being much higher at other frequency's & volume levels. 

My kit amp that is 1600ohms at its highest & that I said paired well with the 10k Arcam was actually rated at 800ohms by the designer..which he measured at 1 frequency. 

In your situation without knowing for sure how the Pontus would match I would probably try something like the micro first. Then if maybe you don't care for the micro you could go for the 15th. Personally I'd like to hear your thoughts & opinions on the Harmony model. I'm going to give the Pontus a lot more time but I'm not really impressed with it thus far. I've been strictly using my Icon preamp & Fritz REV7 SE speakers but switching amps every couple days. I work from home & listen to music 6 or 7 hours a day..with at least an hour of it sitting between the speakers. I listen to a lot of music. When I'm not playing music I have the TV going thru the dac. It still hasn't even been a week though so I'll pump the breaks on criticizing it more than I already have. 

I think that Harmony uDac looks pretty cool. I like that one has the choice to use their own power supply. The guys at Vinshine think it's a great value piece..which is usually the stuff I'm always interested in. It's getting good reviews but then all these R2R's seem to get that..but this unit is under $1k before tax. No impedance issues either. 

@mattw73  According to Wave Theory, the new Denafrips 15th leans toward the bright side of neutral, in contrast to the warmer sound signature of the original Pontus or Pontus II. The treble resolution is enhanced, but it lacks the rich mids and powerful low-end slam of the Schiit BF II.  When streaming high-resolution OS files, its sound quality might be on par with the Laiv DAC. However, when the Laiv DAC streams high-resolution OS files, the gap becomes more apparent.  In short, system pairing—including the amplifier and/or preamp—is critical. If your system is already bright, the Denafrips 15th might not be the best fit.

@lanx0003 I think I saw that review...headphone guy? 

My experiences have no issues or noticed any brightness. First few days some dullness & maybe some hardness on top but never bright or fatiguing. With my Bel Canto pre & Hypex Nilai amp I feel like I can get a feel for whatever the source or dac has to offer. There is no added thickness to the notes from the 15th..which maybe someone might construe as "lean" but I think it's just relaying what the streamer/source is giving it. 

I played around with it quite a bit this weekend. It might not have the most punchy slam but the bass is accurate. It's tight, detailed, & nuanced. It's kind of weird, it doesn't sound like it's super deep or expressive but I can hear/feel it in the walls behind the couch..different from my prior dac. The 15th also puts the vocalists in it's natural position where my other dac put it a little out front of the speakers no matter the track. 

Using my Ultravalve or SET amp I do get more "meat on the bones" & some extended spatial cues. Maybe a hint more than my sabre dac. I certainly don't feel like it's pulling out any more information or more resolving than a sabre dac. But I can detect the slight smoothness or lack of hardness on the top end in comparison. That is probably the biggest difference. But then I feel you are losing some of the clean edges of the notes in space & perception. There is more depth to the soundstage but without those etched lines separating everything. There is separation..but not as pinpoint focused. 

My wife & daughter went prom dress shopping this weekend. A buddy of mine that owns the regular pontus  came over for the day & brought his Sopra N1 bookshelves. He does feel that there is a level of clarity to the 15th that the original doesn't have. Neither of us mentioned anything of brightness with the 15th & the  Focal's..though his tweeters have more extension & sparkle than my Scan-Speaks. His also produce some serious bass & were too close to the front wall on my set up. He was very impressed with the vocals on my Fritz & was amazed with the Class D Nilai amp..I let him take it home. He thinks if I give the 15th more time it will shift into better focus. He said after a couple weeks his original Pontus just fell into place. He says I'm over critical & if I want better I'm going to have to spend more & to get some bass treatment behind the speakers. 

So yeah, I'm probably a bit over critical..but I already know that when I bring something new or different into the house. The 15th is a good dac..but when these "reviewers" build it up like it's the best thing in its price class I'm going to be honest with myself if I feel it doesn't do all things better than something cheaper. But I have to remember that everything in audio equipment is usually a compromise. A mixture of something great & something ok. There is definitely not that hint of glare or hardness with the R2R that I've experienced with chip dacs. That alone should be worth the price of admission..but I can't help picking something apart when I'm evaluating. But once I decide on something I have the ability to enjoy it for what it's worth. At the end of the day I  love music. I can appreciate a pair of cheap earbuds when I just want to hear some tunes.