Strange. But I'm glad you were able to solve that problem.

  I'm using that kind of stuff while I work on equipment at work (voltages up to 1000V), but I don't see a reason why you need that for the T1. Normally you wouldn't need that unless there is something very wrong with your inhouse wiring. 

  Looks really nice. Unfortunately the price is a little too steep for me right now. But I have oscilloscopes at work that can do stuff like that and more, so maybe I will do some measurements at work.

@sandab   Thanks for the post! I always wanted to do such a measurement but my oscilloscope unfortunately doesn't have a FFT function. I would love to do this on my amp I've built.

  Theoretically it should be possible if the pinout is the same. Of course you have to check the datasheets. Soldering a socket is quite tricky because you don't have any holes for them. I personally don't think it will be worth it.   BTW, i bought two RTC E188CC. Can't wait.  

  I also think that they look like russian tubes. And the Sovtek is really looking similar.   http://www.ebay.com/itm/Pair-SOVTEK-6922-Pre-Ampr-Tube-E88CC-ECC88-CCa-6DJ8-/321141640917

  Thanks. No, it is based on this design here: http://diyaudioprojects.com/Tubes/6DJ8-Tube-Headphone-Amp/   I just made some slight modifications to the power supply. For example the heater voltage on my unit is variable (I set it to 6,3V) instead of a fixed 6V. Technically I could change it...

I finally got my amp together and working. I've been waiting for the parts for about 2 months now. The little T1 is only used as a DAC now. I'm using two Siemens E88CC tubes in my amp for now until I can verify that the amp is working properly. But everything seems to be fine for now after 1...

  He's talking about the capacitors. I agree, the upgrade is worth it. 

  You mean these one?       They are quite nice. I was able to get them for a lot less money than they are normally being selled on eBay.   The sound of these are great. If you can get them for a reasonable price I would recommend it. I'm saving these two tubes for my future amp that I'm...

  Current draw from the heaters is not that relevant. Sure, it shouldn't draw a massive amount of current, but the problem with other tube types is that they have other characteristics. Different capacitances, different curves.   I tried some ECC85 from Siemens with no luck. 3 of them were...

You need to open the cable and then cut the wire.     Or you can drill through the USB A header until the pin for the 5V supply is gone.

  One tube has two triodes inside. One triode per channel. This is enough for a tube buffer. For a full fledged amplifier you need more because you have a more complicated circuit like cathode followers or paraphase amplifiers.

CoiL did help me with identifying the caps. Changing the caps wasn't that difficult because I know how to solder. If you don't have any expirience soldering then take an old piece of hardware and try. If you want to go through with it shoot me a PN and I can give you more information.

Just changed the last caps in my T1. I replaced the really bad Lelon main power caps with Panasonic FR 3300µF 25V caps. They also were bigger than the old ones. I didn't think that I could fit them all inside the case but I managed to do it. Everything is in place and the T1 still works.  ...

I only have old Logitech speakers that doesn't really work anymore. Sometimes they work and sometimes not. You have to jiggle the wires around...I thought why not invest in some good headphone equipment than rather buy new speakers.   Since I bought the new hardware I'm listening to music...

  I already have my eyes on red Valvo E88CC but thanks for the link!

Well, the tube also does look nice! 

Allright, just got my Valvo E288CC.     You can read the review in my review post: http://www.head-fi.org/t/633006/aune-t1-usb-tube-dac-amp-discussion-thread-see-first-post-for-faq/4770#post_10326536   You can also read about changing the caps in the T1 and also what effect this does!

  I think it will improve the sound. The DAC in the Aune is just superb. The DACs on the mainboards I had were always a little shallow and they also had a lot of noise from the EMI inside the case. Getting an external DAC is always better in my opinion. But be careful with the gain setting and...

The Aune has far too little power to drive normal speakers without any amplifier. You need a power amp for that. You then can connect your power amp to the T1 using the RCA outs on the back. I can't really give any recommendation on this topic because I solely use headphones.   I personally...

Allright, I couldn't wait. I just switched the caps I had the replacement for. The rest will have to wait until tomorrow.   Here are some pictures of the process.   I changed the headphone coupling caps first (right ones). ELNA Silmic II 47µF 50V. You have to bend them like that otherwise...

Just got my ELNA SILMIC II. I'm picking up Panasic FR capacitors tomorrow and then I'm going to change the caps inside my Aune T1. I hope I'm not going to break it.   

  Based on your experience and the fact that other people use tubes with a heater current up to 800mA without any damages on the Aune T1 I bought myself a Valvo E288CC for a very reasonable price of €35. They go for much higher prices on eBay. I'm excited. Should be here in the next few days...

  I did use a plastic piece that is 1mm thick. I used my Aune for several hours and the piece of plastic is still in the same shape as before.  I just used some scissors to shape the piece of plastic. Somehow I managed to make a perfect fit. It stays in there if I want it or not.   I have to...