Raal Ribbon Headphones - SRH1A
Mar 1, 2019 at 6:07 PM Post #256 of 7,847
are these the cartridges you talking about"? :wink:

714008790.jpg
 
Mar 1, 2019 at 6:10 PM Post #257 of 7,847
@RAAL requisite Alex

This is great to hear! We need more innovators like you and your team. And this is the right direction that your team has taken for this hobby and industry!
 
Mar 1, 2019 at 7:11 PM Post #261 of 7,847
Hmmmm...
I could bet that this much impact as you described in previous and this post, is from the caps in the amp's PSU, if the amp hasn't been turned on for a while.
While ribbons need only a few minutes of some juicy R&B track to settle the resonant frequency, which still isn't as audible as much as described, PSU caps need about 2-3 days being turned on, no need to play anything. Bass is getting larger and deeper within one day, while midrange gets sweeter, smoother and clearer (loosing the shrill and grit) after 2-3 days...
Maybe I'm dead wrong, but what you say is exactly what happens when electrolytic caps get some voltage and temperature.

The Bryston power amp I have should be thoroughly burned in, as I got it used, though only put around 50-60 hours on it before connecting the SR1a. Could the adapter box be a candidate regarding burn-in? But yea, the change was really quite rapid and pretty big. Pretty interesting...

Have you managed to find the right fit/comfort?

I have, thanks. I flexed the headphone housings inward once or twice and it's a good fit now.
 
Mar 1, 2019 at 7:44 PM Post #262 of 7,847
@llamaluv
What I meant was if the amp was sitting for a while, not turned on, regardless of being already burnt-in?
I'm asking because I've been changing the caps in several Krell, Classe and Pass amps to observe the same kind of changes on all of them. Not turned on for a while VS. letting them powered up for a couple of days, as well as new caps VS. burned-in, exhibit mostly the same behavior, except that very old caps (10+ yrs) will sound significantly worse and never get there.

Adapter box, very unlikely to make that big of a change. Very minor changes, at best. It is basically a one gapped-core inductor far below it's saturation (it's not a transformer) and a bunch of fairly mildly heated wirewound resistors. IME, both of those are not susceptible to significant changes with ageing/burning-in.
Ribbon, possibly in bass, but will not make any audible changes above 100hz. You'll get low-end extension by burning-in, but not gain anything in quantity of it. Mid-high will stay unaffected.
 
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Mar 1, 2019 at 8:16 PM Post #263 of 7,847
What I meant was if the amp was sitting for a while, not turned on, regardless of being already burnt-in?
I see. I have been using the amp every day since I got it late last last week. Yesterday evening when I received the headphones, I turned the amp on for the first time that day, so it was definitely just warming up at the same time I was running the headphones for the first time. I confess I haven't paid attention to how long it's taken for the amp to get fully warmed up and sound its best. So if what I was perceiving as "burn in" was in large part just typical amp warm-up instead, I think I'd have to feel a little embarrassed. :D
 
Mar 1, 2019 at 9:07 PM Post #264 of 7,847
Nah, I'd do the same thing and report what I heard!
Furthermore, you may be completely right about the headphones! My opinion about it shouldn't sway your findings, as I was only briefly paying attention to burn-in, as to me it never seemed to take long or significantly alter their presentation. Though, I had to pay attention to many different things at once during development listening sessions.
Anyway, you'll know what's what because you can repeat the cycle the next day and see if it's really the amp warm-up period or not (and to what degree).
 
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Mar 2, 2019 at 3:06 PM Post #265 of 7,847
I've been thoroughly enjoying my evening -- with these guys:

One thing I will say, however, is that I'm continuously fighting the temptation to turn up the volume past where I would normally allow myself to. One, because I like how they're sounding turned up (duh). But two, because of what's described in "Observation 1" on this page of the 6moons review, which I thought was a pretty perceptive point.

.

Completely concur with this statement - I have no idea really how loud I'm listening with this headphone. Part of me now thinks now I may be setting volume too low to overcompensate. With my Sierra 2 speakers (they have a Raal tweeter) I can listen very happily in near field at very low volumes, and get a massive soundstage.. One quick impression - I've been using this headphone with my digital piano and Ivory 2.5 samples, and it is providing by far the best sound quality of any headphone, for this purpose, that I've ever tried - completely even frequency response across the entire keyboard, no weird resonances, such amazing speed and detail - I can really get into it. Now recordings, this where things get especially interesting, I'll have a comprehensive review in a bit.
 
Mar 3, 2019 at 5:26 PM Post #266 of 7,847
INCREASING THE DE-EMPHASIS ON RAAL-REQUISITE SR1A HEADPHONES

How it works?

Due to open-baffle mode of operation of SR1a headphones, the baffle size determines the acoustical cancellation cut-off frequency. The Carbon Fiber shell size correspond to a 2.5kHz cut-off frequency. Below this point, measured from far-field, the response will be a 6dB/oct. high-pass below 2.5kHz.

In operation, the listener's ear is very near-field and this will counteract the acoustical cancellation due to proximity effect, but not completely. Also, the response will almost flatten below 200hz due to acoustical resistance setup which is used to control the ribbon excursion.

In essence, the response will look like gently rising slope from 200Hz to ~2.5k, at which point it will flatten into a plateau. The difference between 200Hz and 2.5khz will be 4-4.5dB.

To completely compensate for this, a De-emphasis circuit is used inside the Amplifier Interface Box which loads the amplifier.

That is done with the following De-emphasis response:

SR1a de-emphasis curve original.JPG


and this is the impedance:

SR1a impedance original.JPG



Increasing the original De-emphasis



Approximatelly half (or most) of the headphone users will find the tone-balance of SR1a sounding “too open”, “tilted upwards”, “too-hot on top” etc.

Aside from bass response below 200Hz, the tone balance can be easily modified by increasing the amount of De-emphasis used. That will further bring down the raw-response plateau of the open-baffle.

In speaker design, when the speaker voicing is leaning towards sounding “too open” (and yet, the response measures flat), the best approach is to gently start bringing down the response from 1.5kHz. towards highs.

Usually, from 1.5kHz to 5kHz resides the “crossover region” for speakers and it is quite easy to attenuate the tweeter and create a gentle slope between 1kHz and 5kHz. The total amount of attenuation used depends on speaker's directivity pattern, the sound signature of midrange and high frequency drivers used, the room treatment, but when ribbon tweeters are used, a good measure is around 1.5 dB +/- 1dB, depeending on taste, acquired listening habits and so on.

In my trials with ribbon headphones, “softening the bite” of a flat response seems to want a little more of bringing down the plateau. It is not my preferred choice to use them like that, but in my rich speaker designing and listening experience, I can make a very good guess of what is a good measure of departure from flat.

In the following steps, I will show you how to increase the De-emhasis by the “correct” amount of a little more than 2dB, but I will show the results first.

Increasing the De-emphasis resistor value, which is easy to do, will create this response of the circuit:

SR1a de-emphasis curve modded.JPG


This is the impedance that will load the amplifier

SR1a impedance modded.JPG


And this is the difference from the original:

SR1a de-emphasis curve modded vs.JPG


The “pivot point” is a little under 1.4kHz, under which almost nothing happens. This is a good thing, in my experience. If it were lower, the vocals would start loosing size and power. It is gently falling towards 7k, which is also good, smoothly connecting the midrange and highs.

For my system and my ear/brain combo (a nice term coined by Srajan Ebaen) , the sound is a little too melow, but I can see the appeal of this with more forward sounding DACs and amps (which are the majority these days), and especially, being used more to general headphone sound than a “fast whipping” speaker sound. The change was significantly less noticeable with excellent and the least compressed recordings and it made lesser stuff sounding much more acceptable. I think I could get used to it after a while, but I don't think it will be the best option for producing, mixing and mastering music.

How to make the modification:

Place your SR1a Amplifier Interface Box on a table bottom up and remove the bottom cover, unscrewing 4 screws. That will expose the resistors in their frames and their connections.

Now, use the wire-cutters and cut two connecting solid-core naked wires here:

20190303_100854.jpg


And here:

20190303_100838.jpg


The frames that hold the resistors are in tension, so you have bend the wires a little after cutting, so they wouldn't get connected by leaning onto one another as the frame springs back to its natural position, like so:

20190303_141508.jpg


This will disconnect one half of 8 paralleled resistors effectively doubling the De-emphasis resistance.

The remaing 4 resistors will get increased dissipation by 47% each. They won't double the heating, as now the resistance is increased in the circuit, so the current drops. This increse is nothing significan for them. They are already the cool ones in the circuit, as they start conducting only above 1.4kHz and there's not much of sustained power up there in music.

For trials, I have tried diconnecting less than 4 resistors, but I don't think that it was enough to satisfy the audience. However, if you find loosing 4 is a bit too much, unsolder only two and see. Just connect the cut wires back and unsolder one leg of the resistors from the frame.

To easily go back and forth during trials, I have soldered on a couple of switches that I could toggle in a second:

20190303_110737.jpg


So, if you find the tone balance of your SR1a too forward or too hot, this will do the trick!

You will not void the warranty and there's nothing to break, so feel free to try this mod and see how it works for you!

Please contact us back with reports, questions, needing advice or anything else you'd like to ask!

Sincerely yours,

Aleksandar Radisavljevic and Danny McKinney
 
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Mar 3, 2019 at 8:34 PM Post #267 of 7,847
For fun, I briefly tried the 25-watt First Watt J2 while I still have the chance (shameless for-sale plug, link in my sig, k thx!). It sounded very good and sounded familiarly like itself: well defined image placement, solid un-thin imaging, smooth treble, and I'd hate to say "analog-like", but something along those lines. Also, nothing unexpected about the resulting tonality or bass quantity, and bass didn't seem uncontrolled or anything. Also, it was playing fine at loud volumes. Because I like the J2 very much, for the first few minutes, I was like, "Hmm, can I get away with just sticking with this amp and calling it a day?" However, when I tried a nice and percussive dynamic track like this one, it was readily apparent that the J2 lacked the dynamic swing to make the song sound as it really should, and the experiment ended. My takeaway was that it or something similar could be quite sufficient for "casual" listening.

Unrelated: A nice ambient, percussive plankton-fest for the SR1a... Eli Keszler - Stadium
 
Mar 3, 2019 at 9:20 PM Post #268 of 7,847
@RAAL requisite Alex Thanks for the guide! I think that this will address a lot of the comments I get from older generation vinyl guys about the treble on these.

Personally, I find the treble 100% fine on these and I don't run EQ on them either. It's neutral and extremely faithful to the recording, and I run my pair with a Spectral amp to get the maximum transient speed out of them - so I'm not going to personally do the mod, although I appreciate that you guys took the time to figure out the option.
 
Mar 3, 2019 at 9:21 PM Post #269 of 7,847
TL; DR: The finest headphone I have ever heard for well-recorded music


Equipment used for this review:

Luxman 505u integrated amp (100 watts into 8 ohms)
Qobuz / Tidal streaming through a mac
Chord Hugo Mscaler and Qutest
VPI Classic 1 turntable with Nagoaka MP300 cartridge
Schiit phono premap
PS Audio P5

Albums referenced in this review:

Gillian Welch: The Harrow & The Harvest (LP)
Protomartyr: The Agent Intellect
Father John Misty: I Love You Honeybear
Danny Brown: Old
Run the Jewels: RTJ3
Hiro Kurosaki / Linda Nicholson: Beethoven sonatas for violin and piano
Waxahatchee: Ivy Tripp
La Gaia Scienza: Fur meine Clara
La Gaia Scienza: Haydn in London
Everything But the Girl: Idlewild
Alban Berg: Brahms - String Quartets
Fleetwood Mac: Fleetwood Mac
Frank Ocean: Blonde
Kepler Quartet: Ben Johnston, String Quartets 6,7 and 8
Wilco: Yankee Hotel Foxtrot
Tinariwen: Elwan
Alina Ibragimova and Cedric Tiberghien: Beethoven’s Violin Sonatas
Dr. John: Gris-gris
Doric String Quartet: Korngold
Joanna Newsom: Divers
The White Stripes: Elephant
Laurence Equilbey: Mozart, Coronation Mass & Vespers

My background and what I value in musical reproduction

I got into the world of hifi shortly after starting my first decently paying job, deciding to spend what seemed like an extraordinary amount on a Hifiman HE500 and Lyr 2. I plugged the headphone in, clicked play on my obsession at the time, I think it was Martha (DIY band) and started to smile, an entirely new mode of experience opening up for me. And ever since then, I’ve been hooked. I quickly scaled up, buying TOTL headphones, trading up amps, finding out what I liked and didn’t. And what I liked most was a huge soundstage. I remember experimenting with some decent in-ear Shures, they were around $500 new, and realizing immediately that this method of music reproduction had no appeal for me.

Soundstage is more important to me than anything else -- more than an accurate frequency response, more than detail retrieval, more than transparency. It’s why I like the HD800 most out of all headphones, even though I hear more detail with the Utopia, and better transparency with the HE1000. The other thing I look for in my equipment is recreation of a certain roundness or wetness in music - it’s tough to describe exactly what I mean, but when I see a string quartet play Haydn live, the music has this quality of roundness that I’m hyper aware of - the quality of a true analog signal, like in well-recorded, analog vinyl, something like the White Stripe’s Elephant. So when I use “roundness” here I’m talking about an impression of being as close to an analog experience as possible.

My foray into speakers and introduction to SR1a

About six months ago, a revelation came to me: what I had been seeking this entire time couldn’t be found with headphones - I had to move to speakers. I had purchased Ascend Acoustics’ Sierra 2 speakers (which has very similar tweeters to the SR1a that are also made by Raal) the year before, and had been listening to them occasionally, about 10 feet away, in a medium sized room. I liked them a lot. And then one day I experimented, bringing them within about 5 feet, then 4, then 3, then 2. Each reduction in distance actually widened the soundstage and revealed more detail - of course what I was doing was eliminating effects of the room. I found I could listen to hours, enjoying this massive soundstage, getting totally immersed in the music, and no longer feeling the impulse to click around in Roon from song to song; I had reached what was for me musical perfection. I now listen at any point between about a foot and 2.5 feet from my speakers depending on volume, desired soundstage, and imaging. When everything is dialed in and I’m listening in the right spot, I almost visualize the musicians playing in front of me.

I had resorted to my HD800 for those times when I couldn’t listen to speakers in my small apartment. And then I tried @Zhanming057 ‘s SR1a over at @llamaluv’s place - I knew instantly this was the headphone for me. @llamaluv and I both decided on the spot we had to have these. The SR1a does things that I’ve never heard from any other headphone, and in many ways reminds me of the virtues of my Sierra 2 speakers in nearfield - extreme speed, immersive soundstage, pinpoint detail. Compared to other TOTL headphones, I find it most resembles the Utopia, but corrects several of that headphone’s flaws (tiny, close soundstage).

Classical

I feel that the SR1a works well with nearly every classical recording of one or two instruments. Something like La Gaia Scienza’s Fur Meine Clara (fortepiano music of Schumann) just sounds so transparent, detailed, and lifelike; I’ve never heard better through any headphone. I can enjoy an album like this as much through the SR1a as I can with my Sierra 2 speakers. Similarly Bach’s solo music for cello, keyboard, or violin - it doesn’t matter who’s performing, nearly everything I put on sounds fantastic.

With recordings of more than two performers, it gets complicated. Back when I had a Chord Dave, Blue, Utopia and HE1000 I categorized my classical albums in Roon into those that sounded best with the Utopia and those that sounded best with the HE1000 - nearly always there was a definite, clear improvement with one headphone versus the other. Initially I thought that the SR1a didn’t sound so great with string quartets or orchestral music -- but it turned out I had mostly been listening to those albums that were synergistic with the HE1000, not the Utopia. When I filtered Roon to select just those albums I had marked as “Utopia” and tried the SR1a, I found the SR1a often sounded fantastic. For example, albums by Doric String Quartet, such as their recording of Korngold, sounded best to me with the Utopia, and sure enough with the SR1a this recording shines. Same thing with Gaia Scienza’s Haydn in London. Recordings of many instruments, for instance something like Laurence Equilbey’s recording of Mozart’s Coronation Mass & Vespers sounded best with the Utopia, and also the SR1a. The wrinkle here is that I tended to find a substantial portion of my orchestral music sounding best with the HE1000. So - do I think the SR1a works for string quartets and orchestral music? Absolutely, and some of the best I've ever heard with headphones, but it’s recording-dependent, and I do still prefer speakers over any headphone for string quartets or orchestral music.. Other chamber music that I thought sounded good with the SR1a were Hiro Kurosaki / Linda Nicholson’s Beethoven sonatas for violin and piano, Kepler Quartet’s recordings of Ben Johnston’s string quartets, and Beethoven’s Violin Sonatas by Alina Ibragimova and Cedric Tiberghien.

Hip Hop

I gave it a shot listening to Danny Brown and Run the Jewels and determined that there just was not enough low-end slam with the SR1a to listen to this genre with headphones -- I needed speakers. Then I toyed with the setup of the drivers. I closed the fins as closely as I could, and placed the drivers directly on my earlobes. There was a ton more bass - it actually become somewhat visceral, and I got into a few songs. When I tried this setup with acoustic music, though, the sound was a little dense - acoustic music can't have the fins closed all the way in.

Pop and Indie

A range of results with pop and indie music, from unlistenable to fantastic depending on quality of the recording. I’ve always been impressed by the sound quality of Everything But the Girl’s albums online - fidelity is very close to my vinyl, and when comparing the two formats I often can’t tell which I prefer. Listening their 1987 Idlewild I’m loving this clarity, roundness, and immersive soundstage. This works with the SR1a. I love the music of Fleetwood Mac and think their high-res albums on Quobuz sound great. WIth the SR1a I’m completely absorbed in their eponymous 1975 album. This is working too. I never really appreciated The Velvet Underground until I heard Raal’s drivers. The Velvet Underground’s 192/24 albums on Quobuz sound amazing - here again I get a sense of roundness and clarity that’s just so appealing. Frank Ocean’s Blonde is underrated - basically this is an album that requires hi-fi equipment to enjoy - you can imagine Frank noodling in his studio for hours, getting the sound just right on his pro equipment -- not surprising that for most listeners this album didn’t really connect, but with the SR1a, whew, it’s a winner. Another great album with the SR1a that maybe isn’t much of a surprise: Wilco’s Yankee Hotel Foxtrot.

Here’s something that’s not working for me: Waxahatchee’s Ivy Tripp: super compressed, harsh, no sense of roundness with the SR1a - I don’t listen for long - this will require speakers. Something that sort of works is Father John Misty’s I Love You, Honeybear. One of my favorite artists but not music that I think is recorded especially well. On the SR1a, this is certainly listenable but I’m missing something - this too sounds better on speakers.

World

Don’t listen to that much world, but here I had fantastic results with Tinariwen’s Elwan - bass went deep, super deep, I heard such clarity, great roundness and an expansive soundstage.

My Kawai VPC1 Digital Piano with Ivory 2.5 Studio Grands

I often need to use headphones with my digital piano, and have never been very happy with the sound until now. Each TOTL headphone I’ve used in the past has produced strange effects. The HE1000 was too bassy, the Utopia was too closed in. With the SR1a I’m getting a completely flat frequency response across the keyboard, including strong bass. The level of detail that this headphone picks up is phenomenal. Ivory 2.5 comes with many settings where previously I wasn’t able to tell much of a difference, but now the contrasts are much sharper. When I play with the SR1a, all the equipment seems to fade away and I’m left deeply connected to the sound of the keyboard - it’s the most realistic thing I’ve ever heard from digital, and the first time I’ve ever been satisfied with a non-acoustic piano. In a hypothetical where I didn’t like the SR1a for recorded music, I would nevertheless absolutely keep it for the sole purpose of playing with my keyboard.

Vinyl

The SR1a will reveal definitively for you which of your albums were recorded well and which not. I played Gillian Welch’s Harrow & Harvest (well recorded folk) and immediately noticed that sense of roundness that I love, that pure analog goodness. And then I played Protomartyr’s The Agent Intellect (post-punk) and was overwhelmed by the flatness of the sound, compression, and excess treble. I actually like this album with my Sierra 2s quite a lot - perhaps it’s the impact of the woofer which makes it listenable with speakers. Like with my digital music, I am getting a lot of variation in terms of recordings that are synergistic with the SR1a. Joanna Newsom’s Divers sounds great through my speakers; through the SR1a, a bit trebly and little depth. Meanwhile with H.C. McEntire’s Lionheart - imaging, soundstage, depth, frequency response - it’s all clicking.

Other Notes

I was using an ifi ican pro as a preamp into my Luxman 505u - everything sounded thin and too trebly, and then I went directly into the Luxman - so much better! It’s also possible I don’t have the right amp for this headphone, maybe with more power additional string quartets and orchestral music will come alive for me. All of the 192k/24 bit recordings on Quobuz have been sounding amazing with this headphone. Check out Dr. John’s Gris-gris, for example - never liked it with any other headphone. I haven’t found any album from the 60s that I don’t like with the SR1a.

Conclusion

Although I still prefer speakers, this is the best headphone I have ever heard. My comparison set is HD800, HE1000, Utopia, and Abyss TC. The SR1a’s virtues are really apparent when listening to well-recorded music, and the technology and sound are so radically different from what most are used to, I suspect this will be a polarizing headphone. If I were to get any other headphone to supplement this it would be an Abyss. You probably won’t want to listen to much hip-hop with this headphone, but find some excellent classical or pop recordings and you’ll be in heaven.
 
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Mar 3, 2019 at 9:34 PM Post #270 of 7,847
@WilliamWykeham Thanks for the review! I'll create a head gear item for the SR1A's soon and when I do, I'll PM you about posting the review there. One thing I do want to say is that the particular issue with hip hop might be the 505u not being capable of delivering enough bass energy fast enough - that's something I noticed with underpowered amps and the SR1A. If you have a chance, try something with 200+ watts into 8 ohms, and the bass performance might surprise you.

I do think that the Raal has enough bass as it is, and to me that signature is more pleasing than the Abyss Phi which has a hint of indecisiveness in the lower mid range because of the bass energy. The Mysphere 3.2 is my go-to complement for some color in the midrange, when I feel like I need something for less well-processed tracks.

@llamaluv I've noticed this issue with solid state amps all the way up to 75wpc at 4 ohms, but I probably listen to music at 5-10 db louder than you do. 75-80 wpc tube amps are however completely fine (KT88/150 setups), and I do wonder if tube amps have higher current allowing them to be more efficient with the SR1A's at a given volume. Alternatively, it could just be that tubes are slower, and the bass problems don't expose themselves at slower bass attack speeds.
 

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