[monsieurfromag3]

I hate to say it, but this reminds me of RF interference in vacuum tubes. When I listen to Pendant, if I forget and leave my phone too close, I can hear when I’m about to get a text. It sounds like the interference described here in this thread, and it comes from the radio in my phone downloading the data.

This same combination of tubes + streaming digital data = noise concerns me. I wonder whether the nutube is similarly susceptible to RF interference as the tubes in my Pendant, and could the WiFi radio in the SP2KT be causing the noise in the NuTube?

This sounds astute sadly since people have noticed the noise stops when Wifi is turned off.

 

[Palpatine79]

But buzzing from tube does not stops when wifi is off. Thats the bigest problem.

 

[RagnarL]

Hmmm... Why I have no buzzing with my sp2t when I listen Qobuz and Tidal over wifi 2.5 and 5??? May be something wrong with my dap?

 

[madFloyd]

This product sure is getting lots of buzz!

 

[SpeleoFool]

Hmmm... Why I have no buzzing with my sp2t when I listen Qobuz and Tidal over wifi 2.5 and 5??? May be something wrong with my dap?

I'd rather it's something wrong with my theory.... Counter examples like this are good feedback. I assume this is true (no buzzing) on Tube / Hybrid mode and not just OP mode? Does seem like the NuTube is part of the equation, based on other reports.

FWIW, I can also get RF interference on my Hiby R6 Pro (same as with Pendant--quiet digital noise from my phone when it's too close and transferring data), but I've never had that issue on any of my A&K players. I've always assumed that's due to shielding; R6 Pro is all stainless (well, mine is), so maybe something getting in through the screen? Anyway, I've always had a dead silent noise floor with my A&K DAPs.

I suppose I'm bringing up the Hiby, because it's possible that external RF interference (not internal, from the SP2KT radio) is the culprit? That could explain some units not buzzing or buzzing not always being present. Might also be something that affects some units and not others.

 

[nycdoi]

Anybody notice the slight hiss? I noticed this when i was listening at 3am in my bedroom.

 

[Skullar]

Anybody notice the slight hiss? I noticed this when i was listening at 3am in my bedroom.

Did you turn off the light in the kitchen?

 

[rlw6534]

This product sure is getting lots of buzz!

Yeah, the more buzz the better... saves me money...

 

[jaydoc1]

I'd rather it's something wrong with my theory.... Counter examples like this are good feedback. I assume this is true (no buzzing) on Tube / Hybrid mode and not just OP mode? Does seem like the NuTube is part of the equation, based on other reports.

FWIW, I can also get RF interference on my Hiby R6 Pro (same as with Pendant--quiet digital noise from my phone when it's too close and transferring data), but I've never had that issue on any of my A&K players. I've always assumed that's due to shielding; R6 Pro is all stainless (well, mine is), so maybe something getting in through the screen? Anyway, I've always had a dead silent noise floor with my A&K DAPs.

I suppose I'm bringing up the Hiby, because it's possible that external RF interference (not internal, from the SP2KT radio) is the culprit? That could explain some units not buzzing or buzzing not always being present. Might also be something that affects some units and not others.

Just to add to the feedback on buzzing - I demo’d an SP2KT at a local Melbourne dealer (Addicted to Audio) - music via Tidal, with 64Audio Fourte’s & stock 3.5mm cable and no buzzing that I could detect. Listened for about 20 min in a quiet area within the store, tried tube only, hybrid, etc then A/B’d the same setup, same songs on my own SP2K and couldn’t detect any errant noise.
I actually found the 2KT to have a lovely warm sound (in tube mode) vs a more clinical sound from the 2K to my ears and a very quiet background.
Am now considering getting the 2KT as I prefer it’s sound signature, so am interested in how the buzzing issue turns out - intermittent production issue (?), & what might be AK’s response.
JD

 

[RagnarL]

As I understood after reading this thread some people have buzzing issue with their sp2t, some not (mine have no buzzing). So it looks like lotterie and it would be better to check your sp2t before buying if you have that opportunity.

 

[RagnarL]

And yes, I agree with you, sp2t really sounds better to my taste than SP2. SP2T has an edge over sp2 on vocals and percussion, and moreover, it has a warmer and more emotional, more engaging presentation.

 

[Skullar]

And yes, I agree with you, sp2t really sounds better to my taste than SP2. SP2T has an edge over sp2 on vocals and percussion, and moreover, it has a warmer and more emotional, more engaging presentation.

Interesting. I did not find it that way at all. Even in tube mode it felt dryer sounding with sharper mids. Will need to try it out again.

How does the battery life compare?

 

[RagnarL]

Interesting. I did not find it that way at all. Even in tube mode it felt dryer sounding with sharper mids. Will need to try it out again.

How does the battery life compare?

The battery life is a bit longer compared to my ex sp1000m but significantly shorter compared to my Shanling m8 with my Ca Solaris SE and Andromeda 2020 iems (they don't need much power to drive). Somewhere about 8 hours of work offline and shorter with wifi streaming. What about sp2 don't know about its battery, took it from a friend for a couple of hours for comparison.

 

[RagnarL]

Interesting. I did not find it that way at all. Even in tube mode it felt dryer sounding with sharper mids. Will need to try it out again.

How does the battery life compare?

And by the way may be you found the sound of sp2t dryer because of your EE and IMR iems? More than two years ago I had ibasso dx220 and sony ier m7 iem and they required more power to drive than CA iems, so with amp9 (korg tubes) I had dry and thin sound with sony ier m7 and with amp8 I had lush and thick sound.

 

[JasonNYC]

The engineering, hardware, software and QA teams are continuing to test. Hope to have additional info soon. I pulled a new retail unit from the warehouse last week to test myself.

By no means is my testing and results necessarily the issue and I defer to the technical teams at AK who are troubleshooting the issues, but this is my experience:

I have two Internet connections at home, my main is a 1000Mbps/1000Mbps fiber to home connection and my backup connection is s a 200Mbps/10Mbps cable Internet connection. To test, I have disabled my mesh network for my fiber connection and am using the default modem/router provided by each Internet provider and have tested both on 2.4Ghz and 5Ghz separately.

With the 1000Mbps/1000Mbps fiber connection, all streaming when using tube mode or hybrid mode is dead silent. No buzzing, noise or interference with any headphone or IEM that I use or with any of the hi-res streaming services I've used - Qobuz, Tidal, Apple Music, Amazon Music.

When I switch over to the 200Mbps/10Mbps connections, noticeable buzzing/noise for the first few seconds of playback with any of the streaming services, especially when using IEMs in tube or hybrid mode. The noise disappears after a few seconds, once the track buffers.

I've spoken to a few people who all seem to have the same experience as me. Those with faster Internet connections and better mesh networks tend to not hear any noise when streaming in tube or hybrid mode. Those with Internet connections less than 500Mbps tend to hear the noise for the first few seconds of a song while streaming. Others with slower connections have also told me it is less noticeable as they move closer to their Wi-Fi access points and more noticeable as they move away.

All have not heard any noise in tube or hybrid mode when playing tracks stored in internal memory or microSD card. This is consistent with what I have experienced.

My assumption is the additional buffering required for slower connections is what is causing the issue, especially as people who experience the issue report the noise disappears a few seconds after the track begins playing.

Again, this is not official from AK, just my personal experience. I have about 40 hours of playback time on the tube alone and close to 40 hours on the op-amp alone, so about 80 hours between the two.

I'd be curious to know if those not experiencing the noise have faster Internet connections. I do not want to clog up the thread with that info, please feel free to PM me if you'd like.