[mogi]

Anyone switch to the original TI OPA2836? Is it the same as the fake OPA2836 used on DX50? And has anyone tried AD8620BRZ or AD8610ARZ??? Which setup is better guys?
 
Setup 1:
Differential Amp: ADA4897-2
HO: ADA4897-2
 
Setup 2:
Differential Amp: ADA4897-2
HO: ADA4896-2
 
Setup 3:
Differential Amp: ADA4897-2
HO: OPA2836

 

[Gourmand]

Please tell me quite clear!
Am I right if exact capacitors scheme in each channel looks like http://postimg.org/image/566fyo3w1 (sorry board engine doesn't allow me insert pic)
Or else??

 

[CoiL]

  Hi All. Here I discovered MAL203854331E3 Vishay 330uF 10V caps were best for replacement. But unfortunately they were... discontinued. I can't find them in any web shop close to me. Anybody had tested more caps? What about Panasonic AM 330uF 10V ECA1AAM331X, NHG series ECA1AHG331? United Chemi-Con EKMG100ELL331MF11D? Nichicon UVZ1A331MED1TD? Jamicon TKR331M1CF11? All of them have size 6.3x11 mm. But what about sound quality?... And Rubicon 10ZLH330MEFC6.3X11? They can fit too. But sound??
 
I wanna replace to 330 uF only for lower frequency filtering.
Looks like replacement of Vishay MAL203854331E3 is MAL214254331E3. But I even can't find them in store.
Did not find 330 uF 10V Vishay, ordering 220uF... :-\  MAL203854221E3 is this right?

 
Please read the thread more carefully, plenty of info here! I have tested Vishay BC 038RSU caps
 

  I tested all those following caps on my DX50 HO (with quick-change breadboard, all had at least 50h "burn-in" before comparing):
 
* Nichicon FG 100uF 10V
* Nichicon FW 220uF 10V 
* Nichicon KW 220uF 10V 
* Panasonic FM 220uF 10V
* Panasonic FC 220uF 10V 
* Panasonic FR 220uF 10V
* VISHAY BC 220uF 10V
* Panasonic AM 330uF 10V
* Nichicon KA 220uF 10V
* Nichicon SW 220uF 6.3V
 
Some pics I took (some are in camera) for short follow-up review I haven`t had time to write yet:


 
This is by memory atm but here is the list from best to worst (my subjective opinion):
1. Panasonic FC
2. Vishay BC 038RSU
3. Nichicon FG  
4. Nichicon FW
5. Panasonic AM
6. Nichicon KA
7. Nichicon KW
8. Jovial TK UTSJ
9. Panasonic FR
10. Nichicon SW
11. Panasonic FM
 
First 3 are almost same good and one should decide by his own taste/gear synergy. Recommend to try out all those three!
Nichicon FW is also solid choice. But I think You can`t go wrong with FC. 
Nichicon KA and Panasonic AM were quite same sounding to me (didn`t bother to find differences since others sounded better). Despite FR, FM and SW had better detail/clarity than Jovial, I thought they lacked in dynamics/musicality(mids?) and soundstage wasn`t also so good.

http://www.head-fi.org/t/720776/ibasso-dx50-mods/210#post_11644662
 
I actually found 220uF Vishay`s slightly better sounding than 330uF.
They sounded basically same as stock caps with SUEX firmware by Dmitry - very good caps imho!
The ones I used for testing were MAL203854221E3 .
I just decided to go with FC`s because they had airier and littlebit larger soundstage.

 

[Gourmand]

CoiL thanx for response. I read entire thread. I'm just checking my choice by manufacturer part number. Is your's Panasonic FC exactly EEUFC1A221S ? Is your's Vishay BC 038RSU exactly MAL203854221E3 ?
 
But I'm slightly frustrated with low capacity value. Most of in-ear headphones have 16 Ohm resistance. In case of 220 uF low frequencies will be cut off below 1/(2*3.1416*(2*220E-6)*16) = 22.6 Hz. This is not pleasant...

This frequency will be twice (-3 dB) lower than normal signal. On 11 Hz level will be already -9 dB or no signal. Ear doesn't hear this sound. But skull bones accept this frequency range - it creates this STUNNING 

bass which all people love. With 220 uF caps and 16 Ohm headphones this bass won't appear (or equalizer must be used). With 220 uF capacitors at least 32 Ohm HPs must be used. But most of them are not portable. Yes there are some in-ear 32 Ohm HPs or even greater - but they are quite expensive.
 
In two words - for 16 Ohm in-ear HPs capacitors with value 330 uF or better 470 uF must be used.

 

[CoiL]

Upgrades I`m currently using:

HO coupling capacitors - Panasonic FC 220uF 10V (EEUFC1A221S)
LO capacitors - Panasonic FC 100uF 10V (EEUFC1A101S)
HO decoupling capacitor - Panasonic POSCAP 220uF 10V (10TPE220MIL)
LO differential amp decoupling capacitor - Panasonic POSCAP 100uF 6.3V (6TPE100MI)
DAC analog power supply decoupling caps - Panasonic POSCAP 100uF 6.3V (6TPE100MI)

 
Quote:

Is your's Vishay BC 038RSU exactly MAL203854221E3

038RSU is name of the cap series, MAL203854221E3 is 038RSU series capacitor.
 

Most of in-ear headphones have 16 Ohm resistance. In case of 220 uF low frequencies will be cut off below 1/(2*3.1416*(2*220E-6)*16) = 22.6 Hz. This is not pleasant...

In theory! In practics I have not experienced any sub-bass cut-offs (EQ off)! None with my 16-32 IEM`s or HP`s.
Atm I`m listening NIN - Hesitation Marks which has crazy deep sub-bass notes in many songs - nothing is missing and everything sounds superb
 

 
In two words - for 16 Ohm in-ear HPs capacitors with value 330 uF or better 470 uF must be used.

Subjective. I do not agree with word "must". I belive in practics, especially in audio world where every little nuance plays role in resulting sound what we hear.
Starting with tips being used, insertion depth, cable impedance etc.

 

[polyrhythm]

got round to doing the extra caps mod, (already done Panasonic FC 220uF 10V)
pretty happy with my DX50!
 
Thanks Coil, Panasonics are a worthy upgrade.
 
Only heart stopping moment was the yellow screen when I booted up!..............turned out I had not pushed the display ribbon back in firmly enough.
 

 

 

[Gourmand]

Originally Posted by CoiL /img/forum/go_quote.gif
 
In theory! In practics I have not experienced any sub-bass cut-offs (EQ off)! None with my 16-32 IEM`s or HP`s.

We cannot hear difference. But we can feel difference not by ear membrane - but by bones and other head parts. Of course frequencies below 20 Hz do not present in each track. Even they are not exist each  second. They appear only in specific cases, like explosions, tiger/lion roar, some engines, some instruments like organs or else. From HD player I expect it will properly play those sounds. But if sound was cut off below 22 Hz - then it is technically impossible.
 
Coil did you make photos of both board sides with ALL capacitors replaced? I don't remember they appeared in theme. Or at least please add quantity of each cap to the list above.

 

[CoiL]

@Gourmand, all the pictures I took are in this thread: Capacitor breadboard testing, installed FC`s, Installed Poscaps etc. ...just read the thread properly and take a look at thread gallery.
Only pic I didn`t took was HO decoupling capacitor ...didn`t bother to open it again for taking pic. Next time when I`m going to upgrade HO opamps.
 
 
 

  got round to doing the extra caps mod, (already done Panasonic FC 220uF 10V)
pretty happy with my DX50!
 
Thanks Coil, Panasonics are a worthy upgrade.
 
Only heart stopping moment was the yellow screen when I booted up!..............turned out I had not pushed the display ribbon back in firmly enough.
 

 

Great job! Good to hear You like the result

 

[Gourmand]

Did anybody try DX50 with Havi B3 after mod with Panasonic FC 220 caps?

 

[nghiacc]

Hi - having had a DX50, and decided to try a mod for it. I mainly use its LO, so will try the LO mod first. After reading through this thread, so what I will need to do is:
 
- replace the diff amp: it could be either LME49721MA or ADA4841-2YRZ (SOIC-8). Pls let me know what is the latest recommendation? I am just new to modding, so would like to try something simple first
- replace the decoupling LO caps: latest recommendation is to replace it with 6TPE220MAZB  (220uF, 6.3V). Since I don't use the HO much, it is necessary to replace this cap? or can I bypass this cap directly?
 
Thanks for your advice!

 

[Gourmand]

I confirm that replacement of HP coupling capacitors drastically changes sound... Panasonic EEUFC1A221S, FC ELEC CAP 220UF 10V are very good.

 

[CoiL]

  I confirm that replacement of HP coupling capacitors drastically changes sound... Panasonic EEUFC1A221S, FC ELEC CAP 220UF 10V are very good.

Glad You like it! Did You try any other caps too?
Another worthwhile upgrade is changing these:

***
HO decoupling cap - # 10TPE220MIL (7343 case)

The original HO decoupling capacitor is a standard 220uF 10V tantalum in a 7343 case

***
DAC differential amp decoupling cap - # 6TPE100MI (7343 case) or # 6TPE100MPB (3528 case)
I ordered both and trying to fit larger with better specs.

The original DAC differential opamp decoupling capacitor is a standard 100uF 6.3V tantalum in a 3528 case

***
 DAC analog power supply decoupling caps - # 6TPE100MI (7343 case) or # 6TPE100MPB (3528 case)
I ordered both and trying to fit larger with better specs.

The original DAC analog power supply decoupling caps are standard 100uF 6.3V tantalum in a 3528 case

Pretty simple to do also 3528 case size is even easier and should give same result.

 

[Gourmand]

 
Did You try any other caps too?

 
Not yet. Here the minimum number of each one type I can order is 5. I do not need so many extra caps... If I will find place to order less number - then I will.
 
So why differential amp decoupling cap is only 1 and HO decoupling cap are 3? Why both are in the odd number? Can anybody show me circuit diagram with these caps?
 
Please show were DAC analog power supply decoupling caps are on the board and how many must be replaced. Do they really improve sound if they are just a power supply decoupling caps?

 

[H20Fidelity]

I gather its a relatively easy job to replace the headphone out and line out jacks?
 
Are the jacks soldered on by only the three solder tabs shown in this photo?
 

 
Anyone know where that part can be purchased, or even the newer jacks used on DX90 and DX80?
 
 
Edit: Could you even bend the contacts on the stock jacks to retighten the connection? Possible maybe with a screwdriver carefully? 

 

[shagrathborgir]

I gather its a relatively easy job to replace the headphone out and line out jacks?

Are the jacks soldered on by only the three solder tabs shown in this photo?




Anyone know where that part can be purchased, or even the newer jacks used on DX90 and DX80?

I can tell you for shure,that jacks from dx90 wont work on dx50!for dx50,you just havr to write an emal to ibasso team,and they will ask you for just 5usd,for the postal taxes.they won't charge those jacks for you.ibasso team is 10+! They charge 10 usd,for fixing a dx50 unit!!!you pay more for postal taxes than repairing a unit!!!!