4 years later... Its working. But it has really audible high pitched distortion and noise. That's when powered straight from my desktop, or trough my powered USB hub. Dunno if it's coming from the GrubDAC itself or added later on by the v3 amp. Ah well. At least I can shelf this project in...

  You read my signature wrong. I don't have the 1440.

Done! Just waiting on Joneeboi to tell me how to wire the amplifier to the DAC and I can fire this puppy up! I'm crossing my fingers this version actually works.  

Well poop. My phone can't stream audio trough the USB OTG cable. How lame.   So yeah, I'm not coming to the meet as I have no setup to bring.

I'm a sad kitten. =(   I bought the Android cable for my Momentums, but it's not compatible with my Moto G. So I think it's time I upgrade my phone. Any of you have an iPhone or a Samsung Galaxy I could try my remotes with, confirm that they work? The box of the Android cable says it's...

Well that's sad.   I own a Motorola Moto G with Android 5.1   The stock, apple certified cable only allows for play and pause. I cant take call or hang up using the remote, and the microphone does not work. Volume up and down does not work either.   So I bought the RCG M2 cable from...

Ugh, my USB OTG cable was lost in the mail. I just ordered another one. Hopefully it gets here soon enough so I can confirm that I have a setup to bring or not.

  That's great! Thanks!   I'll wait to receive my USB OTG cable and confirm I can use my smartphone as source. Otherwise there's no much reason in me attending.

Wow!!    These scale surprisingly well! Listening to them right now out of my Audio-gd NFB-12 and they SHINE. With electronic music they are by far the best headphone I own. That bass is so perfect.

Is anything in this pile of junk of any interest to you peeps? I would not want to carry all that out of the island through bus transit just to have it sit in a corner in need of love.      I sadly don't have a laptop anymore, so I just ordered a USB OTG cable. I'll try to hook my DAC to my...

I bought a new, larger purse to carry these around with me at all time. I think that speaks for itself.   

Seems reasonable. At least you know where you're going with the design.   I have a bunch of op-amps I got over the years, some sent as free samples and others given by friends to try out. Sadly I never had the chance to try them out as all my gear is using discreet circuitry. I could use one...

Interesting design. Quite simple.   Can you explain why you decided to go from a 3 channel design to a 2 channel one? Isn't it a step backward in accuracy?

  It's simple, and to be done with any tube amp: Only plug the headphones in once the amplifier has warmed up and unplug them before powering it down.

So my scanner proved to be unable to take pictures of PCBs, so I went on and bought a DSLR. Here's what I could do with it. You can download the originals and zoom in all you want.        

  Nothing happened to my caps when I first powered the amplifier up. I doubt 1.9 V is enough to kill them... but anyways. You think I should try to power the board without the caps in, see what happens?   I'll take my scanner out and scan the bottom of the board. Pictures later today.

  Moves around 2 K ohms.    I measured just about everything I could think of but didn't find any short.

Alright so I reversed the caps, but I still only get 1.9 V out of the LDO. What's more, I only get 1.9 V at the input of the LDO. I'm guessing it's shorted and pulls the DCP into over current protection. Pulling the LDO out and the DCP outputs 24 V.   Interesting to note is the polarity of...

Holy smokes! I never realized those capacitors had a polarity! Nice find! I'll switch them the right side tomorrow. Thanks a lot! :D Hopefully my ldo is not fried and will still work after that...

  OK I'll go digging trough some data sheets tomorrow.   If there's no way to have more than a guess-timate on how much current my headphones draw, I'll just take my amp meter out and test them. That should work, right?

  Ok noob questions: How do I calculate the quiescent currents and the current of the load?   I'm guessing if I can find the output RMS voltage at normal volume, and the impedance of the headphone, I can calculate the load current. But how do I find the RMS output voltage?   I'm clueless...

  Lol. If you see a big mushroom cloud East of your place, and that I never report back, you'll know the experiment will have failed.    No but seriously. If I don't get more data on the specifications of the Carrie I won't fool around and order the 750L10. It's just twice the price.

Ok I give up. Plan B: Is it safe to replace the 750L10 with a 78L10? The later has a current capability of 100 mA compared to 150 mA for the 750L10. I searched the thread but can't find a consensus on how much current the Carrie draws.

  That's what I figured... But I felt obliged to clarify things in case he was using the same mod but on a 12AU7 build. 

Anyone has got one or two TL750L10CLPR to spare? I don't feel like paying 20$ of shipping for a 0.82$ part. =/