[wirefriend]

I inspected AMP2 today.

It's gonna take a while until I finish circuit inspection, draw up alternate opamp design and upgrade AMP2 module with my own design. Initial impressions of AMP2 gives fuller and smoother sound but also less quiet and has worse transparency as well. I'm not sure how much modding can improve with AMP2 module since AMP1 seems to have lower noise and cleaner sound from design.

Regards,
Keetakawee

Could you compare AMP1 modded to AMP2?
Is AMP2 fuller and smoother than AMP1 modded?

 

[WindowsX]

Could you compare AMP1 modded to AMP2?
Is AMP2 fuller and smoother than AMP1 modded?

I'll leave that to other users in Thailand to give impressions.

 

[WindowsX]

Today I detected advanced ROM user having unusual download activity. I've flagged that account in blacklist for future update. I hope I won't see him again.

Regards,
Keetakawee

 

[WindowsX]

Finished modding AMP2 today using design based on Emm Labs DCC2 SE. Here's my finding.

2x470uF Aluminum caps
22 tantalum caps
2 balanced to unbalanced converter opamp
2 output drive opamp
2 current feedback buffer

I hope this information will help fellow DIYers.

Regards,
Keetakawee

 

[wirefriend]

I believe I can since I am in same city as him. Just wait headphone shop import amp2 module and WindowX came back after Munich event.

Did you have a chance to listen to both modded AMP1 and the original AMP2 ?

 

[artpiggo]

Not yet my friend. Will appoint him soon.

 

[WindowsX]

I've finished a new mod today. This time I by-passed soft mute protection circuit completely for better sound. It will route from output stage directly to lineout/headphone/bal jacks. This makes DX200 sounding much more vivid and live. You will hear short burst sound when amp module starts but it will work fine afterward. I also changed capacitor to single big cap for solid full sound.

Oh, artpiggo also listened to this recent mod yesterday saying it sounds great with his Oriveti IEM with Brimar cable.

Regards,
Keetakawee

 

[wirefriend]

Is the mute-bypass a part of standard (public) or the premium software mod?
Or is it a part of the hardware mod?

 

[WindowsX]

Is the mute-bypass a part of standard (public) or the premium software mod?
Or is it a part of the hardware mod?

By-passing soft mute circuit is hardware mod on amp module with similar approach to famous AK by-pass mod. But instead of by-passing resistor output, we by-passed actual soft mute circuit that actually degrade sound quality to avoid burst spike during amp initialization stage. Since the burst length was very short for 3-6V in acceptable volume, it won't damage any headphone similar to burst in older DX50 design.

This is quite complexed tweak and it took us two whole days to by-pass this soft mute circuit directly to lineout/headphone/bal outputs properly. We also added that highend grade of orange tantalum caps on lineout jack to properly by-pass the signal without interference to headphone output. It's worth the effort and I can understand why iBasso put this protection on. Some end users may not appreciate small burst on during power on like old school stereo systems.

Regards,
Keetakawee

 

[pkersamsam]

will you be updating the custom fw with the newly version from factory?

 

[WindowsX]

will you be updating the custom fw with the newly version from factory?

Sure. I've just got my DX200 back today after leaving it at technician's place to repair damaged AMP1 module unit during DX200 ultimate modification experiment. I'll start cooking 2.3 ROM and publish update soon in this week.

Regards,
Keetakawee

 

[WindowsX]

Sad news today. My DX200 is now bricked because power outtage during firmware update. I'm having another unit working on ultimate modification project so I'll be able to finish 2.3 update after the operation is over.

I've been helping myself with Gin Tonic right now to cure my broken heart. And it was getting onto the good parts for awesome ROM updates.

Regards,
Keetakawee

 

[Lurker0]

RockChip SoC based devices can't be bricked by interrupted firmware update, because they have bootloader in masked ROM. iBasso DAPs have power button connected via power controller, so pressing and holding power button for 5-10 sec (depends on device) always turns power off. Then FactoryTool should be able to flash it again, as usual.

If you didn't physically damage the SoC, of course, by other means...

 

[jamato8]

RockChip SoC based devices can't be bricked by interrupted firmware update, because they have bootloader in masked ROM. iBasso DAPs have power button connected via power controller, so pressing and holding power button for 5-10 sec (depends on device) always turns power off. Then FactoryTool should be able to flash it again, as usual.

If you didn't physically damage the SoC, of course, by other means...

That is what I thought also. I have read that they can't be bricked and having the BT is a great thing to have around.

 

[WindowsX]

RockChip SoC based devices can't be bricked by interrupted firmware update, because they have bootloader in masked ROM. iBasso DAPs have power button connected via power controller, so pressing and holding power button for 5-10 sec (depends on device) always turns power off. Then FactoryTool should be able to flash it again, as usual.

If you didn't physically damage the SoC, of course, by other means...

Thank you for trying to help but I've been holding power button for a few seconds or even a minute again and again for a few hours. It didn't work even though it was just fully charged from battery. I suspect unit being malfunction too as flashmode started to have reliability issues recently.

Regards,
Keetakawee