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
Drop Panda Frequency Response
EARS coupler + SBAF compensation (perceptual neutral approximately straight vertical line across)
The Jotunheim R was amp created mostly for the RAAL Requisite SR1a Ear monitors. RAAL Requisite is an outfit which has made boutique pro gear. The idea behind the SR1a was for a portable pro mixing or mastering platform. The SR1a requires a converter box for use with speaker amplifiers. Without getting too deep into the details, there are a bunch of resistors and coils inside the box so that speaker amps can drive the RAAL ribbon, which is in essence a short circuit. The ribbon is just a piece of metal tape bathed in a magnetic field. Those who have DIY'd speakers using RAAL ribbon drivers know that they come with a big massive box behind them. Inside this box is a transformer that allows power amps used to driving 8-ohms, 4-ohms, maybe even slightly lower, to feed the 0.2-ohms of the ribbon (or something close to that, but you guys get the idea). What the Jotunheim R does is offer a direct drive to the ribbon, without anything in between (more on this next paragraph).
The iFi Micro iDSD BL could be the finest transportable all-in-one amp/DAC unit I have heard. It might be interesting to compare to the Chord Hugo 2 under more controlled circumstances (blind and in a home setting) however; but that may need to wait. Or maybe not, since the Hugo 2 at $2500 is meant for people who's parents in a totally different wealth bracket. For what it's worth, I didn't care for the Hugo 2. However to be fair, I may have judged it based on performance to cost, or I could have had the the wrong filter settings that did not suit my preferences.
Last year we were super selective. There were few winners. Not much gear really got the senior members excited as many nominations were veto'd for an award. This year however is totally different. Lots of great stuff worthy of GS awards. It can even be argued that the DS gear deserved GS awards. I almost feel bad about giving out so many awards because the award is supposed to be selective - not everybody is supposed to be a winner. But the fact is, lots of great stuff this year, and some quite affordable too.
I picked one of these up for cheap, thinking it would be be Class D based on its light weight. (I'm still looking for a class D amp that I find satisfying). Looks like I could have gotten fooled (explains why I actually thought this thing sounded too damn good for class D?). I realized that only the Crown DriveCore stuff or DSi series are officially stated to be class D. Crown's lineup is extremely confusing. I'm not sure that even their reps can explain. I don't know if the CDi (non DriveCore) is class AB? Crown is very coy about a lot of shit these days.
Not all digital transports are created equal. Bits aren’t bits. We’ve seen this through the evolution of CD players as well as USB as an audio interface. The quality of the transport matters, even with modern computer-based digital audio solutions that claim to have vanishingly low jitter.
Many are eagerly anticipating the launch of Unison USB for Schiit’s upgradable DACs, wondering “does it really beat SPDIF?”, “is it better than AES”? I’ve had a Unison USB Beta board in my Yggdrasil A2 for over a year now and have been extremely impressed with it from the start. It has handily beaten any other USB implementation I’ve heard (granted I’ve never heard the TOTL stuff like the Berkeley Alpha USB or the dCS Network Bridge).
Before we even say another word about this, we need to start here: https://www.superbestaudiofriends.o...vc-fd01-a-new-contender-for-best-dd-iem.6500/
@james444 is always digging up random IEMs and modding them with impressive results. He posted a few before and after measurements of the mods, and before long, we purchased a JVC HA-FD01 from a Japan to send along on our loaner program. Most of the folks who heard the loaner, at least those earlier in line, should be aware that I had only implemented a quick and dirty version of the mods. The "authentic" @james444 mods were much more intricate. I think @zerodeefex can tell you guys what a pain in the ass it was for him to do it right. I hindsight, I guess I could have paid my kids (with their smaller fingers) to do the proper mod for me. Anyway, the point I wanted to make is that the proper mods result in better bass quality compared to the quick and dirty version.
According to the Wood Database, this wood is as hard (3,260 janka lbf) and dense (75 lbs/ft3) as African Blackwood: https://www.wood-database.com/desert-ironwood/
(harder and denser than Cocobolo)
FR measurement (not Jude's but Zach's) looks interesting too. Not sure about which pads were on each. @zach915m may chime in.
I've spent a fair amount of time with this "Shortest Way" amp. I still have some comparison testing to do, especially with the ZDT Jr. but have enough thoughts to get started.
So, what is this thing?
- Single-ended, Triode, using 6Z51P tubes
- Output transformers (two types of steel to improve performance at a smaller size, would have to use regular, larger transformers if more are produced)
- Class A
- No capacitors in signal path. Really just a pot and a few resistors, that I can see, plus tubes and OPTs.
- "No feedback except natural communication through the cathode resistor"
- Short signal path