[osocan]

The best combo I heard so far, which makes one wonder: should I have gone for the AP bundle or this is already good enough for an old man.

 

[bmichels]

LOL! You ask too much I know it isn't night/day...but it is zero difference. So...1. I'd like to know if I have a defective unit. 2. I'd like to help others determine if they do as well.

Cayin C9 it is noticeable, N8ii, Hiby RS8, same.

With all the little issues we all have, I just don't want something that we all assume to "normal" to be missed.

Argh, I can look & listen to this all day.

This DAP has sort of revitalized the hobby for me and my overall enjoyment of spending hours listening to music. I went through a phase of only having short 20-30 minute sessions while I was making my early morning breakfast or perhaps during dinner. The N30 makes me want to spend hours listening to music rather than being glued to the TV when I have free time at home watching whatever I can to pass the time. I have missed this feeling.

Very encouraging for someone like me waiting for delivery. May I ask which HP/IEM you use with your N30 ?

 

[davidmolliere]

The best combo I heard so far, which makes one wonder: should I have gone for the AP bundle or this is already good enough for an old man.

Is that the Orpheus?

No hissing with that cable ?

 

[Andykong]

A brief 24-hour update after our announcement regarding the hissing issue of N30LE.

We have continued our study on the hissing problem. According to our working theory by the end of day 1, the problem is related to specific capacitive loading characteristics that show up in unit variance occasionally. It only exhibits in Class A and Hyper mode, so we focused on the working current of the discrete headphone amplification circuit.

After numerous tests and auditions, we managed to eliminate the hissing problem on the returned N30LE by adjusting the bias setting of the discrete headphone amplifier circuit. For those who are unfamiliar with the discrete circuit of N30LE, please refer to our explanation in Post #195, in which I quote the most relevant paragraph below for your reference:

In addition, we must control the static current so that the discrete components will remain perfectly stable operation in saturation mode, therefore adjustments is needed to compensate for the deviation caused by discrete components. As illustrated in the PCB photo below, there are FOUR adjustable resistors in place. We’ll fine-tune each assembled PCB manually to match our reference design. All these procedures involve extra resources and are very time-consuming, that’s why discrete Class A is an expensive option, especially on compact devices such as portable DAP.

We have noticed that by re-biasing the circuit to a new parameter, the hissing problem is eliminated completely, and if we adjust the bias setting back to previous parameters, the hissing problem will reoccur, so we are pretty sure that this will solve the problem from our Engineering point of view. The bias setting will affect both Class A and Class AB playback, the change to audio performance is minimal and inaudible.

However, we need some time to verify our solution. As of today, we have received 3 hissing complaints from China (including Hong Kong) out of the 120+ units we delivered. We have only received one returned unit and that’s the base of our problem-solving exercises. We’ll pick three N30LE from our inventory, adjust the operation bias to our new reference parameters, go through the QA process again, and send out these DAPs to the dealers of the three users who reported the hissing problem. Assuming the new batch of DAP can pass the hissing test with the IEM/headphone/cable that they had trouble with previously, we’ll send out another batch of N30LE to our overseas dealers immediately, and they can replace the hissing N30LE of their client. We believe this arrangement will minimize the delay of our users from sending out their N30LE DAP to receiving an N30LE replacement.

 

[RonaldS86]

Is that the Orpheus?

No hissing with that cable ?

I think that's Deep of the Universe, the stock cable of UM Multi Mentor.

 

[aaf evo]

Very encouraging for someone like me waiting for delivery. May I ask which HP/IEM you use with your N30 ?

Mostly FF Grand Maestro.

 

[RonaldS86]

A brief 24-hour update after our announcement regarding the hissing issue of N30LE.

We have continued our study on the hissing problem. According to our working theory by the end of day 1, the problem is related to specific capacitive loading characteristics that show up in unit variance occasionally. It only exhibits in Class A and Hyper mode, so we focused on the working current of the discrete headphone amplification circuit.

After numerous tests and auditions, we managed to eliminate the hissing problem on the returned N30LE by adjusting the bias setting of the discrete headphone amplifier circuit. For those who are unfamiliar with the discrete circuit of N30LE, please refer to our explanation in Post #195, in which I quote the most relevant paragraph below for your reference:




We have noticed that by re-biasing the circuit to a new parameter, the hissing problem is eliminated completely, and if we adjust the bias setting back to previous parameters, the hissing problem will reoccur, so we are pretty sure that this will solve the problem from our Engineering point of view. The bias setting will affect both Class A and Class AB playback, the change to audio performance is minimal and inaudible.

However, we need some time to verify our solution. As of today, we have received 3 hissing complaints from China (including Hong Kong) out of the 120+ units we delivered. We have only received one returned unit and that’s the base of our problem-solving exercises. We’ll pick three N30LE from our inventory, adjust the operation bias to our new reference parameters, go through the QA process again, and send out these DAPs to the dealers of the three users who reported the hissing problem. Assuming the new batch of DAP can pass the hissing test with the IEM/headphone/cable that they had trouble with previously, we’ll send out another batch of N30LE to our overseas dealers immediately, and they can replace the hissing N30LE of their client. We believe this arrangement will minimize the delay of our users from sending out their N30LE DAP to receiving an N30LE replacement.

Thank you Andy for the update. I'm glad with the progress and I hope that is really the root of hissing problem.

 

[osocan]

Is that the Orpheus?

No hissing with that cable ?

Multiverse Mentor with stock cable. No hiss.

 

[ClubQ]

How on earth is our dealer supposed to confirm the problem when you can’t even confirm the problem reliably? Are we supposed to also ship our dealer the exact headphones and cable that cause the problem?

I sold my other DAPs to fund this purchase. I would be much more comfortable if you worked with dealers to get replacements shipped out to them /before/ we ship our units back. I really don’t want to sit here without a DAP for weeks.

Just an update. I also sold Susvara headphones & other equipment to fund this purchase Plus paid £7,000 in cash. Cayin have today agreed to replace the Amber Pearl DAP. But I’m being told by the dealer that I have to return my unit before the new N30LE will be dispatched from the factory. This leaves me with nothing. Surely they could send the new unit before I have to return the existing unit. This is annoying to say the least. I have trouble with my vision so the only enjoyment I get is from my music. Now I have nothing for at least a week. Not happy.

 

[Damz87]

The best combo I heard so far, which makes one wonder: should I have gone for the AP bundle or this is already good enough for an old man.

This is the exact same thought I’m wrestling with. Mentor sounds awesome with N30 so I’m now thinking about Amber Pearl

 

[Torq]

It only exhibits in Class A and Hyper mode, so we focused on the working current of the discrete headphone amplification circuit.

That might be true for the "common" hissing issue.

Be interesting to see what you find when my unit is back in your engineer's hands. As it was hissing (loud, waterfall/white-noise hissing) regardless of mode. And it only occurred after getting hot - which would affect impedances and physical tolerances - so it could be the same issue and just have been "on the edge" in terms of bias settings ... and getting warm pushed it "over" into a problematic region.

The intermittent static that accompanied the hissing was also a factor ... though I expect that is a different issue - maybe marginal NuTubes (as, despite their differences from normal tubes, the static sounded just like that you get from noisy signal tubes in regular tube amplifiers).

Should have my replacement unit today ... fingers crossed ...

 

[aaf evo]

That might be true for the "common" hissing issue.

Be interesting to see what you find when my unit is back in your engineer's hands. As it was hissing (loud, waterfall/white-noise hissing) regardless of mode. And it only occurred after getting hot - which would affect impedances and physical tolerances - so it could be the same issue and just have been "on the edge" in terms of bias settings ... and getting warm pushed it "over" into a problematic region.

The intermittent static that accompanied the hissing was also a factor ... though I expect that is a different issue - maybe marginal NuTubes (as, despite their differences from normal tubes, the static sounded just like that you get from noisy signal tubes in regular tube amplifiers).

Should have my replacement unit today ... fingers crossed ...

Hope your unit is okay this time around

 

[osocan]

This is the exact same thought I’m wrestling with. Mentor sounds awesome with N30 so I’m now thinking about Amber Pearl

Hope UM release a standard version of the Amber Pearl

 

[Allears79]

A brief 24-hour update after our announcement regarding the hissing issue of N30LE.

We have continued our study on the hissing problem. According to our working theory by the end of day 1, the problem is related to specific capacitive loading characteristics that show up in unit variance occasionally. It only exhibits in Class A and Hyper mode, so we focused on the working current of the discrete headphone amplification circuit.

After numerous tests and auditions, we managed to eliminate the hissing problem on the returned N30LE by adjusting the bias setting of the discrete headphone amplifier circuit. For those who are unfamiliar with the discrete circuit of N30LE, please refer to our explanation in Post #195, in which I quote the most relevant paragraph below for your reference:




We have noticed that by re-biasing the circuit to a new parameter, the hissing problem is eliminated completely, and if we adjust the bias setting back to previous parameters, the hissing problem will reoccur, so we are pretty sure that this will solve the problem from our Engineering point of view. The bias setting will affect both Class A and Class AB playback, the change to audio performance is minimal and inaudible.

However, we need some time to verify our solution. As of today, we have received 3 hissing complaints from China (including Hong Kong) out of the 120+ units we delivered. We have only received one returned unit and that’s the base of our problem-solving exercises. We’ll pick three N30LE from our inventory, adjust the operation bias to our new reference parameters, go through the QA process again, and send out these DAPs to the dealers of the three users who reported the hissing problem. Assuming the new batch of DAP can pass the hissing test with the IEM/headphone/cable that they had trouble with previously, we’ll send out another batch of N30LE to our overseas dealers immediately, and they can replace the hissing N30LE of their client. We believe this arrangement will minimize the delay of our users from sending out their N30LE DAP to receiving an N30LE replacement.

Given that the problem was identified and there will be a new reference parameter applied which seems to be more correct than the current one for the delivered units, wouldn’t that be the case for a recall? What if most users who still didn’t come across this issue (because they don’t use the specific incompatible cable or IEM at the moment) start having the issue in the future?

 

[Allears79]

Hope UM release a standard version of the Amber Pearl

I’ve tested a few IEMs and cables and despite not having heard the Amber Peral I REALLY struggle to understand how anything can be possibly more contagious, energetic and lifelike as the Orpheus +Aroma Jewel combo with the N30LE. It is just insane