pkcpga
1000+ Head-Fier
When I use the m15, I have the pendant on a night stand by my bed, cable is long enough to have the m15 in bed. When the pendant is at my desk it’s connected to a regular dac.
FiiO M15 Audio Player | Dual AK4499EQ | 7490 mAh Battery | 64 GB ROM | $1299.99
- Thread starter xenoVa
- Start date
hmscott
1000+ Head-Fier
I wonder which JJ tube they sent for the 12AU7 position, the ECC82 or ECC802s?
For the Xduoo TA-20 I found the JJ ECC802s Gold Pins was quieter and had a wider sound stage with more enjoyable dynamic sound. And, after a few days the JJ ECC82 Gold Pins pair (brand new) started to HISS, which was very surprising. I returned the JJ ECC82's, but still very much enjoy the JJ ECC802s.
Curiosity - hoping for hiss free tubes - led me to try the Tubedepot "Cryogenically Treated" JJ ECC82 "Black Sable", and I was surprised to find I didn't like how the JJ ECC82 Black Sable sounded compared to the regular non-treated JJ ECC82 (before it got hissy), and even more surprising was that the Black Sable JJ ECC82 pair I had were even more hissy than the un-treated pair - so I returned the Black Sable JJ ECC82's as well.
I should mention once again that when using regular headphones there was no hint of noise or hiss from the Black Sable or untreated JJ ECC82's, it was only when using sensitive IEM's show hiss.
Listening on hissy tubes the KZ ASX or NICEHCK NX7 MK3 show so much hiss that they are unusable even at higher volumes. The KZ ZAX is a bit more usable - you can hear the hiss, but much reduced, and even less hiss comes through on the BQEYZ Spring 2, TinHifi T2 Plus, Blon BL-03.
I haven't tried all of my IEMs for hiss sensitivity as I am really enjoying my new headphones on the Xduoo TA-20, and even though I am culling any tubes that show hiss on my IEM tests, I am mostly spending my time listening to the Hifiman HE6SE V2 and Hifiman Ananda, with a bit of time on the Sennheiser HD660s.
I really enjoy the JJ ECC802s - modeled after the Tesla / Telefunken ECC802s. You can easily spend many times the cost of the headphone amp filling it with rare NOS tubes, fortunately there are new tubes being made that are recreations of the past gems, like the Telefunken Black Diamond reissued ECC802s.
pkcpga
1000+ Head-Fier
Stock JJ tubes on the pendant I received with my vintage set was:
JJ ECC82 definitely looks like a very short plate compared to my vintage tubes
JJ EZ81
Pair of JJ EL84s
hmscott
1000+ Head-Fier
Yes, that is the physical difference that suggests the sound difference - the ECC82 is a short plate and the ECC802s is a long plate. The short plate can sound amazing, but the long plate to me (many?) sounds better with a wider sound stage and greater dynamics and "tubeiness".
In general Long Plates to me sound best, Black / Grey have differing tonality, whichever is your preference may tune your search for new (NOS) tubes.
But, this isn't always a 100% sure thing. I've got a pair of supposed golden tubes that I don't enjoy - the sound is too clinical / "flat", but I think that is enjoyed by some - and I forced myself to keep them in for about a week, and in the end I had a sigh of relief when I switched in a favorite. To put a short tail on it, the Clinical Tubes sound like my Topping A90 - with a smaller sound stage, while the Tubeiness brings in a much wider /taller sound stage and that sweet tube sound.
Clinical: RCA 12AU7 Long Black Plate Matched Pair Top Tilted Getter 1955 - Unknown life %, but Zero IEM noise, I bought on visual queues and price.
Tubeiness: 2 Strong Matched RCA Long Black Plate TRUE D Getter 12AU7 / ECC82 Tubes - 108%/116%, 104%/94%, and no noise on IEM's.
And yes, they are both RCA 12AU7's from RCA, both with Long Black Plates, and the only difference? The getter is different...if I look at them side by side there are build differences. This may be why people are fixated on the manufacturing location and dates of manufacture in their searches to recreate their favorite sound - as tubes only last so long so when you find your golden set, buy a couple of duplicates.
I buy Life % of 95% or higher for price/life, and for noiselessness I am now looking for measurements over 100%, like the Tubeiness example above. When I find a high % pair within a triple or quad, then I ask to split out the good pair, or purchase the set for the golden pair, and hope the lower reading tubes are good as backups.
When I search studiously for my particular tube parameters and stick to my requirements I've found there are still good deals out there without spending a wad of cash.
Last edited:
pkcpga
1000+ Head-Fier
I personally have not liked any new production tubes that I’ve tried so far. I have a pretty good sized collection of nos/vintage tubes. I personally like Mazda 12au7 triple mica silver plate. Also like a Mazda 12au7 with long silver plates military old stock. And Amperex 6201 with gold pins. Never could get into the Mullard (too warm, not dynamic enough) or Telefunken (not enough bass, thinner vocals) tubes. Siemens chrome long plate I also really like. But the Mazda triple mica silver plate spends the most time in the amp with the Amperex el84 pair and Siemens ez81. Between 12a*7 whether u,t or x, I have 11 to swap between (seem to make the most significant sound change) and 4 pairs of el84’s and 3 ez81’s (very little difference besides the JJ which has some low hmm sound when no music is playing). I wish I could find a few more Mazda 12au7 triple mica silver plate, but they seem to be impossible to find. Or even the Mazda 12au7 or 12at7 long silver plate. They seem much harder to find. If anyone has any leads?Yes, that is the physical difference that suggests the sound difference - the ECC82 is a short plate and the ECC802s is a long plate. The short plate can sound amazing, but the long plate to me (many?) sounds better with a wider sound stage and greater dynamics and "tubeiness".
In general Long Plates to me sound best, Black / Grey have differing tonality, whichever is your preference may tune your search for new (NOS) tubes.
But, this isn't always a 100% sure thing. I've got a pair of supposed golden tubes that I don't enjoy - the sound is too clinical / "flat", but I think that is enjoyed by some - and I forced myself to keep them in for about a week, and in the end I had a sigh of relief when I switched in a favorite. To put a short tail on it, the Clinical Tubes sound like my Topping A90 - with a smaller sound stage, while the Tubeiness brings in a much wider /taller sound stage and that sweet tube sound.
Clinical: RCA 12AU7 Long Black Plate Matched Pair Top Tilted Getter 1955 - Unknown life %, but Zero IEM noise, I bought on visual queues and price.
Tubeiness: 2 Strong Matched RCA Long Black Plate TRUE D Getter 12AU7 / ECC82 Tubes - 108%/116%, 104%/94%, and no noise on IEM's.
And yes, they are both RCA 12AU7's from RCA, both with Long Black Plates, and the only difference? The getter is different...if I look at them side by side there are build differences. This may be why people are fixated on the manufacturing location and dates of manufacture in their searches to recreate their favorite sound - as tubes only last so long so when you find your golden set, buy a couple of duplicates.
I buy Life % of 95% or higher for price/life, and for noiselessness I am now looking for measurements over 100%, like the Tubeiness example above. When I find a high % pair within a triple or quad, then I ask to split out the good pair, or purchase the set for the golden pair, and hope the lower reading tubes are good as backups.
When I search studiously for my particular tube parameters and stick to my requirements I've found there are still good deals out there without spending a wad of cash.
hmscott
1000+ Head-Fier
Great list of tube experience, far beyond mine, I'm still new at this. Most of those you mention are on my list to acquire when the price is attractive. Right now I'm branching out a bit, selecting 12AX7, 12AT7, 12AX7WA tubes with triple mica with 100%+ measurements and a matching triple mica 12AU7 that I can use to test the Xduoo TA-20 ability to take other than 12AU7's as shipped.
When I test my M15 feeding the Xduoo TA-20 / A90 via 3.5mm cable I'll post my results here...along with other M15 related info
Perhaps we should move the tube talk to an appropriate on topic thread, either Pendant SE or Xduoo?
Last edited:
I’ve heard some people say that the m15 sounds better after a little while from burn in? I also bought a Verite Cable which I feel as it does make and audible difference from my Hart Audio Cable.
Last edited:
LightBlue77
500+ Head-Fier
or it is just brain adjustment it sounds very well though with good recordings and good headphones.
Be prepared tough to be annoyed by software and reaching unbearable levels of temperature, especially when using balanced output.
it sounds very well though with good recordings and good headphones.Be prepared tough to be annoyed by software and reaching unbearable levels of temperature, especially when using balanced output.
Me personally, I also believe burn-in is just or more so brain adjustment more then everything setting in like with burn-in with headphones and cables. But that’s just me.or it is just brain adjustment
Be prepared tough to be annoyed by software and reaching unbearable levels of temperature, especially when using balanced output.
Maybe because I’m used to Gaming Laptops that run hot, I’m not really noticing much heat at least not as hot as im used to.
Does anyone know if the M15 supports MQA over USB Dac mode?
LightBlue77
500+ Head-Fier
I guess it depends on the software sending the bits to m15.
The M15 does not support MQA when it is using as USB DAC. But we will try to add the MQA support in our new DAC products.
Best regards
hmscott
1000+ Head-Fier
It would also be nice to create a "mode-less" interface which allows for interaction with Android while in what is called "USB DAC Mode", "Bluetooth Receiving Mode", and even "Pure Music Mode" - if possible.
Hopefully, the main CPU will be strong enough this time to allow multi-tasking operation of the "mode"/app/service along with interactive Android use.
Users who are viewing this thread
