Super Best Audio Friends

Standard Prologue
If you are unfamiliar with audio measurements please use a search engine with the query:
"audio measurements" or "audio measurement handbook"
Look for publications by Richard C. Cabot and also by Bob Metzler, both from Audio Precision. There are other useful publications as well. These will provide basic knowledge.
Interpretation of the following measurements is beyond the scope of technical measurements posts.

Notable highlights:
First, well done Doug and CeeTee! This is an incredible headphone amplifier.
Nearly perfect gain linearity spanning over 110 dB range in balanced input operation
± 1 dB gain linearity over 120 dB range in balanced input operation
SNR greater than 123 dB in balanced input operation
Excellent square wave response
Bandwidth: DC to greater than 168 KHz
Clarity and tube magic yet no tubes

Twelve years ago (and I can't believe it's been that long), a lot of headphones sounded like shit. To be precise, many had horrible treble peaks or irregularities that hurt my ears (and the ears of @Hands, @rhythmdevils, etc.). My reference back then were speakers that I had built that met a neutral target (neutral on-axis / B&K AES 1970 target at listening position), so many headphones left me scratching my head. Why the fuck is the treble so rough and peak I was thinking! I was avid Head-Fi poster back then trying to convince to fellow Head-Fiers what I heard was real. My approach ended up as this: https://www.head-fi.org/threads/headphone-csd-waterfall-plots.566929/

Finally get to properly A/B test my Lawton Chambers...

Wild Ziricote
Wild Ziricote by Hilton, on Flickr

Wild Chechen
Wild Chechen by Hilton, on Flickr

So I bought one of those new Rega ‘Reference’ belts for my old Planar 3. But even if you’re not one of the handful of Rega owners among SBAF, you might like to keep reading as this is mostly about measuring and visualizing wow & flutter, and evaluating different measurement techniques, than about the belt itself (especially the first two 2-3 posts). Conversely, if you DGAF about the details of the measurements and are mostly interested in the new belt, you can focus on the third 4th post.

TLDR: Using the Wow and Flutter Visualiser plug-in for Audacity in conjunction with the WFGUI software wow & flutter meter is more informative and probably more accurate than using phone-based apps, and almost as easy (but not as portable). And yes, the Rega Reference belt is pretty good, but it runs slower than some others - which might be fine if you're not using a PSU, as uncontrolled Regas usually run fast; or can be compensated for if you're using the speed-adjustable Neo PSU.

What with the development and release of high-end audio music servers (not referring to streamers or network bridges here, but the actual computer system that serves up music files) e.g. Taiko Extreme, Pink Faun, and Grimm, etc.,
I just purchased an Intel NUC i7 in an Akasa case with Roon ROCK installed from a local seller in Palo Alto for only $350.

I've dubbed the Akasa NUC "Alita, Battle Angel"

This thread will start with a series of posts describing the set-up and with photos depicting the implementation so that it's easy to follow along.

It's in a fanless Akasa case which is dead quiet and keeps the computer cool.


The purpose of this project was to compare my current 2012 Mac Mini-based Roon Core, which my hypothesis was would be "noisier" as it's powered by a SMPS, has an internal fan, and quite bit of unnecessary "overhead" of componentry and functionality. Eventually, I'll likely be powering the Akasa NUC with a quiet linear power supply, but right now, just powering it with a laptop-style 19V/3.6A SMPS.

First of all, I need to apologize to @VinylSavor because I put myself on the waitlist but had to change my mind at the last minute. Thomas had notified me that 300Bs were ready the very next day a friend asked me if I wanted to buy a used pair of Elrog 300B! (I still may order a new pair of Elrog 300B, just not now because of the economic uncertainty of the WGA strike).

Also, what's the rush? I've been in his hobby long enough to know that the most important thing to do is to enjoy the music RIGHT NOW instead of fussing and worrying about optimizing (listening to tubes instead of music). This process of optimizing eventually comes anyway and is best done at a deliberate (slow) pace. The sad fact is that 80% of people (thanks to HF FOTM mentality) usually trade away a critical component of their system before optimizing it to anywhere over to 90% of the system capability, thus needing to start over again. An audio system tailored toward one's sonic vision rules over any individual component.



tl;dr: The Elrog 300B is the best 300B ever period.

eXperience innovation!

The Diablo-X is the first DAC/amp on the market to support the revolutionary xMEMS‘ solid state monolithic speaker technology.

This unique technology features:

• Ultra-fast mechanical response (~15µsec; 150x faster than a typical dynamic driver)
• Flat 2° phase response for more accurate sound reproduction
• +/- 1° phase matching (part-to-part) for more accurate spatial sound
• Silicon speaker diaphragm (95x more stiff/rigid than plastic) for reduce speaker break-up (less muddy mids/highs)

Brian Lucey, 8-time Grammy Winning Mastery Engineer, calls it “truly disruptive’ with “phase performance unlike no other speaker technology”. Discover why in 3 minutes.

Hello north TX friends,



LSA (self-billed as "the Woodstock of high-end audio shows" lol) will be going on from Friday, June 2 to Sunday, June 4 this year.

• It will be held at the Embassy Suites Dallas Galleria in Dallas, TX.
• There is no price of admission for attendees.
• Here's the schedule for the weekend, which starts at 10am and ends at 6pm each day.
• If you're thinking about exhibiting your system, here's the registration form for a room.

Would be good to get a nod from each of the folks who are planning on attending, and we can also post impressions and pics here as well!

About a year ago, someone on Reddit asked me to help them navigate the morass or products out there, to write a guide. To do this comprehensively would be difficult if not impossible, but as I thought more about this, I came up with some ideas. I will eventually write a Newbies Guides to the Galaxy of Personal Audio, but not today.

Somewhat related to this, I felt it may be a good idea to discuss what I am personally using (members please chime in). I've slipped hints to readers here and there: the secret to knowing what is good is not necessarily what reviewers say is good, but to ask the reviews what they actually use themselves. Case in point: we all know Amir has some pretty awesome shit in his house that isn't Topping.

BTW, it's frustrated me that so few people have asked me what I actually use (keeping in mind that I have stuff at various price points lying around the house). What it comes down to is that most people see something shiny and new - and want confirmation that they made the correct choice. Whatever people want, I will oblige.

Over five years ago, I wrote a review for the Massdrop x Input Club K-Type keyboard. I definitely don't count myself as a mechanical keyboard geek, but I certainly do appreciate nice things. This keyboard was pretty good for it's day. The only thing that sucked about the K-type was the included stabilizers, which I wrote a guide on replacing them in the article. Fast forward five years later, I got another chance to examine keyboards again, mainly because my son wanted one. I got him a Drop ENTR which is a decent base (much better than the discontinued K-Type here as it should be). However the switches that came with it, the Halo True, didn't work well for his purposes. They lacked feel and required too much pressure to depress. They were horrible for gaming. In addition, several of the keycap stems broke. And they weren't on the WASD keys mostly used in gaming, more like the J key. My son said screw this and decided to build his own keyboard from scratch with a Glorious base and Cherry MX red switches, but that is another story.

When I moved to Texas a few years ago, my K-Type got damaged in shipping. I had no idea how this happened because the keyboard was stored in its original box which did not look damaged. I mean this is supposed to be a solid piece of aluminum right? How the heck was this even possible?

I recently finished restoring an early model HH Scott 222d integrated amp, which is actually the circuit from the 222c, just with a different face plate. Along the way I decided to add the biasing circuit from the 299b. It turned out great and unseated my Ragnarok 2, not on technicalities, but on musical enjoyment. I've come to accept that I just like vintage stuff and I like tubes and I'm ok with that. Then I came across a cheap Scott LK-48 for sale locally and grabbed it. It's the same circuit as the 222c, but again with a different face plate, and uses 7199 tubes for the phase inverter instead of the 6UB tubes in the 222c/d I restored already, although some 222c's did use the 7199. Anyway I'm starting to restore/mod the LK-48 and will keep a log here.

I forgot to take before pictures, but the first order of business was to clean off the dust/grime and remove the output transformers and power transformer bell cap for a repaint. They looked similar, but a little worse, to the condition of the transformers on the 222c, which I failed repaint and will do later. Here's the unpainted transformers on the 222c/d

LK-48 with transformers and bell cap removed:

*Considering that every single ETA thread for some reason is drawing drama, this will act as the official thread for loaner impressions and conducive discussion.

ETA O2 Impressions


If you have had the chance to listen to a good unit of the old pre-fazor Audezes and wondered what it would sound like as a dynamic, look no further. The ETA O2 is in many ways a similar headphone: a rather interpretive listen, one that is somewhat unhinged and wholeheartedly unrefined energy (especially in the highs) but not in ways that are necessarily negative. If the Utopia (when driven by synergistic amps) is a posh, stuffy, properly-mannered suited up guy, the O2 is the borderline gangster who wore backwards hats back in the early 2000s and rode a skateboard while carrying around a boombox. There's room for both.