[hdtv00]

Yep 100% correct Amperex Orange Globe for sure. With varying sound slightly by the different getter types. But yep that's where you want to start for sure.

 

[CoiL]

Our friend Coil has done _tons_ of research on this (and other) topics. Maybe do a little digging in the archives. There is so much that goes in to sound perceptions, such as "warm".

I did a lot of research into this a few years ago, too. If I recall, the short answer is that lots of people prefer vintage Amperex Orange Globes. I bought a pair and agreed they were the "warmest" and most holographic to my ears.

Yep 100% correct Amperex Orange Globe for sure. With varying sound slightly by the different getter types. But yep that's where you want to start for sure.

Agree with above. Start (end) with Amperex OG because it is quite easily available as NOS or used (which is fine in T1 buffer implementation) and really is great tube match for Aune T1 hardware.
There are some very similar sounding(even better) tubes but they are hard to find and probably cost a lot.
Green label JAN Sylvania 6922 is also nice and quite easily available but rather towards V-shaped in FR compared to OG.
When you decide to get OG - prefer version that is made in Heerlen Holland factory (delta sign) and has single leg supported dimpled disc getter.

Good luck!

If You have opportunity or skills for hardware modding, then I highly recommend to upgrade capacitors - it makes a lot difference and is cheap upgrade.

 

[wgkwgk]

When I had my T1 I did a lot of rolling and narrowed it down to four tube "keepers", one of which is the OG. I have that in the A-frame version and three others (CCa Seimans 1968, Mullard CV2492 gold pins, Telefunken E88CC1) just sitting in their boxes. All NOS (late 60's early 70's). I never got around to posting them for sale. PM me if interested.

 

[GS1874]

I'll leave this here in case it helps someone. After about 5 years my Aune T1 recently failed, which of course bummed me out. I spent several days troubleshooting the problem and was able to recover it for not too much money.

One of big input electrolytic caps had failed and was leaking goo. These filter the main +/- 18VAC power input and turn it into +/-23VDC rails. I could actually hear it sputtering when the oil was leaking out of the caps. Caps were 3300uF, 25V (C35 and C36). The size, especially the height is important so they fit in the case. Replacement caps I found in stock that fit the space were Nichion UBY1E332MHL1TN.

Unfortunately during this event an onboard switching regulator that steps down to 5V also failed. This is marked U9. Good news is these are available on ebay. Search for KIS-3R33S - DC DC converter 7-24V in, 5V, 3A out. You may have to buy it as part of a PCB and desolder it. It might have a plastic case around it. Be a little careful as there are several similar little DC DC converters sold under the same PN that are obviously a completely different footprint. Also, even though the footprint was the same I had to add a 10k pulldown resistor to the DC DC converter adjust pin to make it put out 5V. There is nothing tricky going on with that supply, it just steps 24V down to 5V. So if you can't get one, really any step down DC DC converter with appropriate rating could work.

U11 which is a -15V LDO also failed. I noted another post where someone had this part fail too. This turns the -23V rail into -15V. It was passing -23V to the output instead of regulating to -15V. There is a +15V LDO right next to it. It's an ON Semi part labeled 79M15G. I could not find this anywhere and struggled to even find an ON datasheet for it. I replaced it with MC79M15CDTG, which is also a DPak size and 500mA.

Finally I also had to replace the tube, one side somehow got messed up during that event and was distorting the signal. Interestingly, the tube is in a common anode configuration with the output taken off the cathode. The gain is basically 1, the signal passes through the tube but is not amplified at all. Also the heater voltage is only 5.0V but Electro-Harmonix gives possible range as 6.0 to 6.6V. I have no idea how this affects the sound.

 

[CoiL]

Caps were 3300uF, 25V (C35 and C36). The size, especially the height is important so they fit in the case. Replacement caps I found in stock that fit the space were Nichion UBY1E332MHL1TN.

Panasonic FR caps have very good specs, are widely available and cheap for that replacement. Other caps, use Panasonic FC if want cheap and great sound, SilmicII or Cerafine if have more money and want "the best".

 

[Cheesedoodle]

Anyone familiar with Aune's new version — the T1s 4th Gen? Looks like it might be a nice upgrade. I only see it online in a few places, and very little info online about it generally. Currently looks a lot more expensive than its predecessor (around $500).

 

[CoiL]

Anyone familiar with Aune's new version — the T1s 4th Gen? Looks like it might be a nice upgrade. I only see it online in a few places, and very little info online about it generally. Currently looks a lot more expensive than its predecessor (around $500).

Very interesting indeed! Though, with such price I`m afraid it won`t sell and might bring T1 to end. Hope they lower price noticeably.

Btw, anyone can recommend cheap tablet with android which is able to connect Aune T1 (1st gen) as DAC via USB (ALSA) ?
I have one old tablet which is totally fine for music player on desk or shelf but it doesn`t identify T1 as android version is too old and CPU doesn`t support external DAC (currently using it for iMM-6 IEM measurements).

 

[Old Deaf Donkey]

Just got a Schiit Vali 2, using the Aune T1 as DAC only. So far the quality of the sound is great. Seems to have more depth than the Anne's onboard amp, despite years of faithful service. I'm going to do some AB testing to see if I'm correct about the improvement.

That's my endgame. Gorgeous sound with AKG K702. various tubes, currently twin single triodes Sylvania VT-192 in aune T1, and Ken-Rad black glass VT-231 in Vali 2.

I also use another setup that sounds great: aune t1 Mk3 with Koss E90 and ESP-95X.

 

[CoiL]

That's my endgame. Gorgeous sound with AKG K702. various tubes, currently twin single triodes Sylvania VT-192 in aune T1, and Ken-Rad black glass VT-231 in Vali 2.

I also use another setup that sounds great: aune t1 Mk3 with Koss E90 and ESP-95X.

Get rid of those crappy stock capacitors in Aune T1 too
I stopped tube-rolling after about 80+ tubes... especially after getting rare 5x Siemens-Halske E88CC golpins and finging some "same sounding" cheap alternative family tubes, + Amperex OGs and some other great rarities (Miniwatt, Ultron, Pinnacle).
But "ENDGAME" sound quality came after upgrading DAC differential opamp (OPA1692IDR) and HO opamp (OPA2228). I wasn`t hoping wonders from opamp-rolling and thought in the end would still have to buy separate amp... but luckily no

 

[Old Deaf Donkey]

Get rid of those crappy stock capacitors in Aune T1 too
I stopped tube-rolling after about 80+ tubes... especially after getting rare 5x Siemens-Halske E88CC golpins and finging some "same sounding" cheap alternative family tubes, + Amperex OGs and some other great rarities (Miniwatt, Ultron, Pinnacle).
But "ENDGAME" sound quality came after upgrading DAC differential opamp (OPA1692IDR) and HO opamp (OPA2228). I wasn`t hoping wonders from opamp-rolling and thought in the end would still have to buy separate amp... but luckily no

Thank you for the suggestions. Unfortunately, I do not have soldering skills. So, changing capacitors and opamps is beyond my options. Aune t1 Mk3 DAC sounds quite good already as is, would improvements be noticeable? I am only using the DAC.

 

[Cheesedoodle]

The new 4th gen T1 apparently has upgraded capacitors (and DAC chip), so that might be an option to consider if you want upgrades but can’t solder. I’m definitely eyeing it.

 

[CoiL]

The new 4th gen T1 apparently has upgraded capacitors (and DAC chip), so that might be an option to consider if you want upgrades but can’t solder. I’m definitely eyeing it.

Old one also uses WIMA caps in certain places. Seems those bi-polar caps would be "improvement" but no mention about 1st and 2nd stage power filtering caps, which are very important.
4th gen T1 main improvement probably comes from DAC chip over older versions - ES9038Q2M vs. DSD1793.
Also, seems MK4 doesn`t have any gain swithing option anymore (not sure though) but additional feature is AptX BT5.0.
https://www.auneaudio-europe.com/in...ver-4th-gen-headphone-tube-amplifier-dac.html

 

[Cheesedoodle]

That's helpful, thanks.

It does seem the gain switch is still there. Quoting from the page you linked to:

Gain switch 0dB

10dB
16dB
​

Bluetooth addition is kind of a bummer, in my opinion. I guess they have to add it these days to make it "future proof," but it adds to the cost and is probably a feature many audiophiles won't use.

Old one also uses WIMA caps in certain places. Seems those bi-polar caps would be "improvement" but no mention about 1st and 2nd stage power filtering caps, which are very important.
4th gen T1 main improvement probably comes from DAC chip over older versions - ES9038Q2M vs. DSD1793.
Also, seems MK4 doesn`t have any gain swithing option anymore (not sure though) but additional feature is AptX BT5.0.
https://www.auneaudio-europe.com/in...ver-4th-gen-headphone-tube-amplifier-dac.html

 

[CoiL]

Aaaah yeah, sorry, didn`t notice gain lvls.

 

[exSpire]

Hey guys. I'm having noises coming from the right channel on my Aune T1.
Yesterday I took it apart, cleaned it up inside and somehow it worked. I figured that the problem was solved. However today the issue is back. Any ideas of what it could be?
I've taken some pictures of the boards.
Thanks in advance.

https://imgur.com/a/bP2Quvu

I can take better pictures of certain area if needed, just let me know.