I’ve just pulled the trigger on the Gjallarhorn and an XLR banana plug cable from Aliexpress.
@MindBreak can i connect the amp to my Fiio R7 using RCA cables or does it need to be connected to a dac amp (i’ve got an iFi Zen Dac v2) via balanced?
If its the latter then i need some advice on what cable i will need because the Gjallarhorn requires a mono XLR jack whereas the Zen can only be connected via a 4.4mm pentacon jack.
think the mono is for if you use 2 for monoblocks not a single unit
rca out from r7 or zen to the rca gjal would be fine
I think adapting the 4.4 out of the zen to rca would also be fine
With the R7, which headphone output are you using? I think the balanced output is really good but, IIRC, the unbalanced is not the best.
@SemperMalum i have got usb output from R7 to the Zen Dac. I have also got an XLR to RCA output which currently is hooked up to my Little Dot Mkii tube amp. So ive got a bit of choice although the LD Mkii is definitely not an option for the Horizons.
Currently, i have got the Horizon plugged straight into the R7 via balanced XLR. Just about enough power to drive the headphones at full volume on Ultra Gain. But i can feel these headphones need more oomph to get the most out of them.
Btw, i have been back-to-back listening to Talk Talk’s ‘Spirit of Eden’ and ‘Laughing Stock’ albums via the R7. I am loving the sound profile of the headphones, they have got excellent timbre. These albums contain a lot of subtle musical passages which are excellently conveyed through the Horizons. I dont feel like i’m listening through a pair of headphones, they are really quite unique in that respect. I am not hearing anything that derives any negative impact to the experience, its all positive. So i really can’t wait to hear what they’ll be like hooked up to the Gjallarhorn’s!
I’ve currently got the Horizons hooked up to my Astell&Kern PA10 amp, which is connected via balanced lineout to my Fiio M15s DAP. They sound even more awesome, even with the PA10 running at full pelt to drive the headphones. The music sounds so sweet and pure. The PA10s are very linear and clean, great match with the Horizons. I am really enjoying these headphones, i am definitely happy i made this purchase.
Just one thing to add. After you get everything hooked up and powered on, make sure you have your volume set to zero before connecting the headphones. Then play a test track, and slowly turn up the volume until you reach your desired level. Depending on the preamp used you won’t have a lot of play in the knob, but make sure you are in low gain or that will be reduced further.
I still have a hunch that the Mjolnir 3 might be able to power Horizon. Granted it took a lot of burn in to get it to the point of sounding good with my Starry Night V1. Right now I have it set to Push/Pull, High Gain, and the volume is at around 10 o’clock. I am not using the stock cable, but instead using a Corpse Cable Gravedigger XLR cable. I have a few 2 x 3.5mm headphones so it was worth the investment for me.
Edit: don’t get me wrong, the Gjallarhorn still has more slam and deeper bass notes when powering the Starry Night V1. 
It’s cool that SJY has provided a variety of options for the external grills. Given the differences in material and geometry, I can’t help but wonder if there are measurable/audible effects depending on which option you choose.
The thin mesh behind the driver may lessen this to an extent but it shouldn’t entirely eliminate the differences in airflow and reflection.
I’m loving all the info and pictures so far
Welcome to Hifi Guides! Glad you are enjoying the SJY Audio discussion.
Edit: If you haven’t noticed yet we are a crazy bunch, but enjoy talking about the hobby!
Thanks for the warm welcome. You guys come across and level-headed in my estimation. 
The HF thread is a bit of a poisoned well at the moment (due to posts from another manufacturer) so this seems to be the best place to participate.
I don’t own an SJY yet but I do have a Flux FA-10 Pro that may be able to handle them. From what has been described thus far, people who own some of those compact SMSL/Topping/THX amps that seem to be current limited at the output should be cautious and expect a lean presentation.
I am also on that HF thread by the way. Same handle as this one
In regard to Topping/SMSL amps, I did give the Topping L70 a shot to see if it would work out for me as a secondary setup, but the only headphone I could stand on it was the HD660s. Let alone the power issues as well as an issue I found with the preamp outs when connecting it to my Gjallarhorns. So…, yeah… I would stay away from the low to mid level amps. The Asgard 3 sounded better than the L70. For slightly more than the price of the L70 you can purchase a Jotunheim 2 and have a more capable amp. If you haven’t noticed I am very Schiit Centric! 
Schiit is a reasonably priced option for US domestic customers for sure. I’ve heard some reports about noise issues from their new little power amps which is kind of shame but maybe it can be sorted.
Flux Audio Labs’ relatively cheap class AB amps probably have enough power but my Pro variant is tuned to be neutral-bright as it turns out so maybe the standard model or the Volot would be better.
Kevin Gilmore’s designs like the Dynahi, CF3, or uberamp would probably work very well with the Horizon.
Time to pull the trigger on that Topping A70 Pro purchase 
. 17W of power here I come.
I will stick with my 2 watts of class A thank you, but I see that the power of Topping compels you. 
Sometimes, mo-powah is the answer.
I see your 17 watts and raise you 30 watts of class AB! 2 x Gjallarhorns FTW! 
got my Horizon today spent a bit of time just plugging them into everything I currently have set up, been surprised so far how many things seemed to run them well.
Been using the Horizon on my Archel 3 Pro - while I do have to go to 3-4’o clock, it’s been a great combination. Horizon so far has exceeded how I felt about the Umi. Jeffrey knocked it out of the park.
Also, can we talk about how satisfying the magnetic pads are?? Damn. I can’t wait to see what future pads do for the tuning.