Super Best Audio Friends

The evolution of the original irreverent and irrelevant and non-authoritative site for headphone measurements, i.e. frequency response graphs, CSD waterfall plots, subjective gear reviews. Too objective for subjectivists; too subjective for objectivists

Animation of the previous three measurements Again, observe how CF is nearly the same for all three but considerably different amounts of NFB are utilized for each amplifier design.

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Several key points to remember:
1. THD+N masks differentiating distortion components
2. Each amp has different D2 / D3 sweep signatures
3. THD+N @ 1 KHz is 0.00216% for Heresy and 0.00252% for Magni – very similar – yet sweeps demonstrate clear differences between them
4. 4+HD+N is nearly identical for all three amps in the range of interest

20220529 Poll Results to date:
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Between these measurements and the SBAF poll one might infer a preference exists for amplifiers with lower NFB needed to achieve a particular CF distortion performance.
Well, there's been a lot of buzz about this cute little box, but surprisingly enough, I don't see a thread on it here. I bought a B-stock unit from Schiit after hearing some trusted SBAFers say a few too many nice things about a product that's about a tenth or a twentieth the cost of a lot of the gear we purchase here, so I thought I would buy one to see what the hype was all about. A few days later, my B-stock unit from Schiit arrived, and I was quite surprised at just how tiny this little thing is...

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Yeah, it's small, especially compared to the Mjolnir. But it packs a good punch. I'm going to discuss the dac here, as all my headphones are higher impedance, and so aren't really a good fit for the amp. According to some others, the amp works great with low impedance phones, though they'll have to verify that with impressions.
I am not new to Chord DACs. I have owned a Mojo1 and a Hugo 2 and have tried the Dave with and without M-Scaler a couple of times in the past. I was once a Chord fan boy, as I was led to believe that other DACs don’t hold a candle to the Chord DACs. But I discovered later that there wasn’t much truth to that statement.

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Depending on where you are coming from, the tone of the Mojo2 will fall anywhere between neutral and neutral-warm. It has an even-handed tone and presentation, with nothing really standing out nor missing. It has a sort of cohesiveness to its sound, which I would say is one of its strengths. An other area, where I am noticing it to be strong is the pace, rhythm and timing, for the lack of better descriptors. Neither slow nor fast. Mojo 2 seems to do these aspects on point. This aspect, combined with the cohesiveness makes for a nice sense of rhythm and flow to the music.
Originally posted at Head-Fi: https://www.head-fi.org/threads/sch...most-improbable-start-up.701900/post-16951998

Texas Audio Roundup
July 22-23
Austin, Texas
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Link: https://www.eventbrite.com/e/texas-audio-roundup-tickets-335542455517

Of course, I'll be there, as well as some other Schiitheads. Hopefully you can come and see us at the first-ever Texas Audio Roundup! All the best, Jason
What I wanted to do next was build out the Frugel-Horns, the XL version that would fit the larger 6" drivers. I'm years late. There are some differences between the FHXL and BK-16. The Frugel-horns have the horn exit towards the back, are of an arguably simpler design, and have a longer section behind the driver with a choke near the exit flare. With respect to use, I gravitated toward the Frugel-Horn because it was designed to be used against the wall, instead of needing to pull them several feet from the walls. The BK-16, especially with the 168ES I sound to be midbassy and murky if not placed at least one to two feet from the wall. Not so with the FHXL where I had them placed against the the wall angled in a bit.

Anyway, I've had always had success with Fostex, particularly their higher-end drivers, so why not? I ended up with the fairly new FE168NS (not ES) but accident because I didn't look carefully while I was on shopping Madisound's site. Oh well, but it turned out to be a happy accident. The NS are based on the limited edition SOL series. I have kept away from Fostex's limited edition series because I never know when one of my kids is going to poke a hole through a driver (boy and girl, but they fight like cats and know stuff over). The last thing I wanted to worry about was to be stuck with one expensive driver with no possibility of replacing the other.

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Snorry NM-1 Impressions. Thanks to @Failed Engineer for loaning these to me! :bow:

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They are probably the best tuned stock ortho I’ve ever heard. Very well balanced from bass to treble, very neutral. Nothing sticks out and there’s no Audeze midrange suck-out. vocals are forward but also there’s no upper mid peak. Bass is nicely layered and textured. They are really meticulously tuned.

They also have the best soundstage of any ortho I’ve ever heard. I don’t know if it’s the driver or the combination of the very deep pads with the very open back or all 3. Instruments are pulled apart and separated with space between them, sometimes even artificially so. Bass lines are easier to follow than Audeze headphones simply because they are separated more from the rest of the spectrum even if the quality isn’t’ as good. Very airy presentation.
The following is a visual guide to amplifier distortion vs amplitude with a schiit Vali 2+ and Ultron 7DJ8 tube as the example.
00 202200510-31 vali 2+ THD+N  4+HD+N vs amp 300R - vol set for 0 dB gain +20 dBu.png
Above is a typical tube or hybrid amp 1 KHz distortion spectrum. This graph will look unusual due to the dual axis delineations. On the y-axis blue is linear in units dBu while yellow is logarithmic in % distortion. Only the log scale is showing. The x-axis also has dual delineations with blue logarithmic in units Hz while yellow is linear in units dBu. This graph has been initialized for a measurement sweep of amplifier % distortion vs level in dBu.

...

Compare and contrast the foregoing extensive amount of data obtained from measurement sweeps against a single observation such as:

0.46% 1KHz THD+N at 2V.

Not only is the level ridiculous as being far above a normal use case, such a simple, single point observation represents a profound reduction of information to evaluate amplifier performance for this attribute.
Today we are taking a look at T+A (Theory and Application) of Germany’s flagship headphones, the Solitaire P. This is a headphone I have been incredibly interested in since its release back in early 2020. Since its release, T+A have also followed up with the Solitaire PSE, which retails at roughly half of the price of the Solitaire P. I hope I can get ears on a pair of those someday as well, as the Solitaire P itself is an incredibly compelling headphone overall.

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The Solitaire P, which for the rest of this review I will refer to as the “SolP” is a planar magnetic headphone, with a sensitivity rating of 101db/mw and 80 ohms impedance rating. Overall, they are quite an easy to drive headphone, and will play well even from lower power source equipment. With that being said, they do seem to enjoy a healthy supply of power behind them, and scale well with an increasing quality of source equipment. The reason I note that they play well from lower output power equipment, is that generally speaking, top of the line planar magnetic headphones have been fairly difficult to drive in the past. There are obviously a few exceptions, but things like the Hifiman Susvara and Abyss 1266TC, are both difficult to drive, the Susvara notoriously so. I was worried the Solitaire P would not play at the level of the very upper echelon of planar magnetic headphones, especially given its $6900USD MSRP ($6200USD at launch.) Thankfully, they absolutely do play at the very top level, and also manage to do some things I have not heard before.
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Finally had time to get my big Moth up and running well. And it is a treat.
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My ZD is really sorted right now and very good with my HD800. Reminding me how good it is. Not a ZD Super, but has had some work by Craig/Marv a few years ago to update it some.

The Moth is better with modded 650. I tried lots of headphones with Moth the other night. I suspect I could roll NOS in place of the new production 6SL7GT driver tubes but it it is already very good! The leading edge transients on Moth are ridiculous, lots of good/quick detail with mids to treble. But with 800 needs some smoothing on top and a bit more bottom end. Elex would be good but bass is missing some control, probably due to needing to adjust internal jumpers for lower impedance. I need to see where the jumpers are at for the speaker impedance inside.

Still some lower level hum with Moth at higher volume levels that might be a ground thing. Using an Isomax though for everything on the table...not as bad as when resistors were bad on regulators. Pulled out the HD600 today. Craig did recommend that exact headphone in the Moth manual...prefer Marv-modded HD650 for cleaner bass.
I can't remember anymore what caused it, but at some point 2-3 months ago, the Dave caught my eye. I don't remember if it was a post somewhere, or a video on Youtube. But something made me pay attention to it. It was then that I started reading more about the Dave and watching some of Rob Watt's presentations. I don't think it's a stretch to say that Chord products don't have a good rep here at SBAF, so I hadn't ever even considered them or paid attention to them or their tech outside of seeing people meme about the tap counts Rob Watts talks about.

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The more I read about the tech inside, the more intrigued I got about the Dave. The things Rob Watts was saying about digital filtering lined up alot more with what I know about digital sampling from my signals and systems classes in school and reading I've done since. (As an aside, Rob Watts has alot of ideas, right or wrong, about why we hear differences in things that we do, his blog on head-fi is an interesting read). I never in a million years thought the Dave would actually be my preferred DAC versus the Wavedream. Based on the other impressions I have read I thought it would turn out to just be soso, and I would sell it off and go about my business, but I was still interested enough to want to hear one, and I wanted to give it a fair shake, postulating that the filtering may take time to appreciate, so I decided to purchase one.
I had planned on getting a Cambridge Audio Azur 851N in for review until COVID messed up the world. Like the Convert 2, the Azure 851N uses the AD1955 part. This is a part that I feel could be one of the best delta sigma chips around, along with the prior generation AKM4399 (used on the Burl B2). I've simply never heard a bad sounding DAC using the AD1955. This is where the ERC-4 comes along. I'm a cheapskate, and I also look for very basic functionality. The Azur 851N is $1500 and has a lot of functionality that I don't need. This is when someone reminded me of Emotiva. Of course! How could I forget them. After all, I've been recommending Emotiva Class AB amps as entry level alternatives to Class D horrors for years now. The Emotiva ERC-4 comes in at $600, which is a bargain. It also can be used as a CD Player (or transport). I know this is extra functionality; but I still have old CDs around and my wife prefers physical media instead of having to mess with Roon.

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The downside is that there is no USB input. The ERC-4 only has coax and optical inputs. If we want USB functionality, grab a cheap used Schiit Eitr (good synergy) or Singxer USB to SPDIF converter. A little bit extra cost, but the ERC-4 at $600 is somewhat of a steal. The sound is closer to that of the well-regarded Convert-2 than the Lavry DA11. The tl;dr version is that the ERC-4 doesn't have the murkiness in the lows of the DA11. It exhibits the clarity, excitement, and sweetness of the Convert-2, and may actually be more resolving...