What AMPs or DAC-AMPs with 4.4 Pentaconn can you personally recommend?
I’m looking to get one but am not sure which one to pick for my GL2000 as the RME is no longer in question for me. I dont really mind the price as long as we are not speaking in solid gold.
The two I own are the ifi Zen Can and the Topping A90
If you want more portability and have a lot of offline files, I can recommend a DAP. Most DAPs have superb 4.4 implementation and is becoming a standard. One bonus with a DAP is that you know it is a machine that is built solely to play music.
I originally thought DAPs were silly and sort of a glorified phone until I got more into IEMs and wanted the portability and having offline files.
I have the Zen DAC…which is a misnomer as it has a built in amp with both 6.5mm SE and 4.4 Pentacon Balanced output.
if you like a warm sound, the Zen is the way to go…as I think the A90 is more neutral / cool.
Well I dont ever listen to headphones on the go, because I’m mostly driving where I have a stereo already, or at work where I have a tube amp and 58X currently. I bought the Mini-I Pro 3 now, and will report back on how good it sounds. Zeos seems to be quite happy with it, hope I will be too ^^
Just get a different cable. XLR is everywhere.
There are also some affordable adapters as well. I personally use an XLR to 4.4, but I know they make one going the other way too.
True, XRL indeed is a good and widely spread option… BUT 4.4 seems to be supported more and more and to me looks like a promising new standard for balanced audio connectors. So a DAC/AMP with 4.4 already built in may be a thing some people like me will look out for specifially. You know? The future 
I’ve been having a great time with mine. The sound out of it is tremendous; it’s punchy, detailed, spacious, “full”, but not lacking for any resolution… great stuff.
I keep trying to A/B other amps or headphones to figure out if this output impedance thing is an issue, but I can’t really hear anything. Bass doesn’t go wild, detail seems to be totally retained, treble isn’t grainy. Even running the 4.4 bal out on v low impedance headphones (5XX @ 18 ohm), it sounds fine. Suffice to say im not super concerned at this point…
Don’t have it but maybe the topping a50s ($200) is what you’re looking for. I got a schiit magnius with a 4.4 to 4xlr adapter instead, which I do recommend.
I just bought the CFA Cascades and they came with a bonus 4.4mm cable.
A) They sound Great out of my Sony DAP (NW-ZX300) via 4.4mm.
B) I bought a 4.4mm to XLR adapter on Amazon. I think it was $40.00.
Now I am covered. 
I have an A90 that has 4.4mm, but prefer XLR because cables are more standard and my LP only has XLR. You can get adapters from 2.5mm & 4.4mm balanced to XLR easy enough. I got my 2.5mm to XLR adapter from Drop, the 4.4mm to XLR from Aliexpress (took about 2 months to show up, so I found a comparable product on Ebay instead). I don’t think balanced really makes a difference except for amps designed to be run balanced.