Need actual listening opinion between DX90 & DX50. Does DX90 sound significant better than DX50 in term of soundstage, separation, clarity and bass?

What about if I were mixed one Sylvania 408A and one Philips 408A? Some headfiers claimed both are equivalent. Any comment?

Has anyone tried to mix the different brand/maker but same family tubes ?   For example, is it ok to mix one WE 408A tube and one GE 408A tube in LDI+?

Are there any different in term of soundstage and separation between them?

Has anyone rolled Op Amp AD8397? AD8397 is used as Op Amp in Hifiman HM-901.

What is the sound characteristic of  OpAmp  LT1364CN8?

May I know your actual listening experience for the same song when playing with both DX50 & DX90?   Between the, which one sounds wider sound stage with more 3D imaging, better separation & layering, smooth & detail treble (high), great mid and extended faster bass?

Between Schiit Vali and Little Dot I+, which is a better choice for low impedance cans like AKG K550 & Beyer DT880 (32 Ohm) ? Which one has a wider sound stage, better separation, more detail ?   Does Vali allow tube rolling ? If yes, what are the recommended tubes for better sound stage and...

Where did the noise come from? Is it humming sound from its transformer? Is your LDI+ a new unit?

May I know if there is any different among these OpAmps:   MC33078 (stock OpAmp in Little Dot 1+) MC33078P MC33078N   Because when searching on eBay, I only can find either MC33078P or MC33078N.

What is the major improvement in sound signature can you notice from DX50 to DX90 ? I'm very interested to know about the sound stage/3D imaging, vocal/instrument separation and bass impact between DX50 to DX90. Thanks.

Does Little Dot, I+ work well with low impedance 32 Ohm headphone like AKG K550?   What kind of tube is good upgrade  for Little Dot, I+ ?

Are you saying the tube amps is not good for driving low impedance cans like AKG K550 or Beyer DT880 (32 ohm)? Any recommendation for tube amp to be used with low impedance cans?

I'm new to Tube Amp. May I know if Cans like AKG K550 and BeyerDT880(32ohm) work well with MKIV or IVSE? I worry about the annoying noise from this Amp? Have you experienced with hum noise from its transformer?

Between Aune T1and Kasso YJ-01, which one has a clearer sound, wider soundstage, good separation, rich and detail, and deep extended bass. Which is one has better match with iBasso DX50?

Between the Aune T1and Kasso YJ-01, which one is a better choice if I want a wider soundstage, good separation, clarity, deep and solid extended bass?

Does DX90 is an upgrade for DX100?

Any sound comparison between iBasso DX50 vs Fiio X5? Which one has wider soundstage, separation, and detail?

Can you explain more how T1 improve the sound of DX50?

+ 1

+1   I totally agreed with you. :)

Can you elaborate about the sound stage and separation and imaging/depth between D12 vs PB2?

It works. Thanks. :)   Some people said f/w1.1.6 has a better SQ than 1.2. Thus, I dare not to switch. :)

How did you go to "setting" page when your screen is freezing?

Has anyone encountered screen freezed problem in DX50? Even if you removed the battery, the problem is still there. How to solve this problem? The firmware is 1.1.6.