[w357]

Here you can find a link to the lay-file, to register for download. ctrl + f - 1886.zip.

 

[Cryok95]

Nope. But i am determined to do this. Thanks a lot w357. I suppose you yourself have done this mod

 

[Hardcorist]

I apologize for the Google translator, but my own English is too weak
 
Quote:

I see, kk plan foiled lol.


Anyway forgive me for asking but i dont really understand this part. Could you care to explain?

after the publication of FAQ, I changed the connection method. Now all the contacts of the operational amplifier mounted on the motherboard again. signal paths on the board, leading the signal from the LPF should be cut. 1,2,4 and 5 contacts of the volume control removed from the motherboard and are only connected to the wire. it is possible to reduce noise and interference from the motherboard to the amplifier. Besides re-enabled feedback to filter the DAC.
 
at the moment, the amplification factor = 3. if you replace resistor 1K for a longer (up to 10K), then you can raise the gain up to 12. in such a player can easily play with headphones with impedance up to 600 ohms.
 
from today I think the project completed. No more changes, I do not want to make.
 
Today, my Ultimate mod unique in the world. I hope my achievements will help many enthusiasts and the number of good-sounding T51 will only increase.

 

[glassmoon]

from today I think the project completed. No more changes, I do not want to make.

Today, my Ultimate mod unique in the world. I hope my achievements will help many enthusiasts and the number of good-sounding T51 will only increase.

respect. wish I could hear/buy one

 

[Cryok95]

Quote:

I apologize for the Google translator, but my own English is too weak
 


after the publication of FAQ, I changed the connection method. Now all the contacts of the operational amplifier mounted on the motherboard again. signal paths on the board, leading the signal from the LPF should be cut. 1,2,4 and 5 contacts of the volume control removed from the motherboard and are only connected to the wire. it is possible to reduce noise and interference from the motherboard to the amplifier. Besides re-enabled feedback to filter the DAC.
 
at the moment, the amplification factor = 3. if you replace resistor 1K for a longer (up to 10K), then you can raise the gain up to 12. in such a player can easily play with headphones with impedance up to 600 ohms.
 
from today I think the project completed. No more changes, I do not want to make.
 
Today, my Ultimate mod unique in the world. I hope my achievements will help many enthusiasts and the number of good-sounding T51 will only increase.

Thanks a lot Hardcorist. Almost have all the info i need for a successful mod. However, one last question. How and where do i mod to cut the signal from the LPF as underlined above?
 
I'm not very technically competent

 

[Hardcorist]

http://img577.imageshack.us/img577/815/13546.jpg

 

[Cryok95]

Still have to solder wire directly from pins 1 and 2 of op-amp to pins 1 and 2 of volume control right? Guess i will have to use a sharp knife to cut the signal paths

 

[Hardcorist]

rightly
 
Quote:

Still have to solder wire directly from pins 1 and 2 of op-amp to pins 1 and 2 of volume control right? Guess i will have to use a sharp knife to cut the signal paths

op-amp contacts are soldered to the board to implement the feedback. then the signal goes through the wires to the volume control. conductors of the motherboard are not involved in this.

 

[Cryok95]

I understand. Many thanks. Will let post some pics and impressions after the mod. Thanks again. Especially to hardcorist and w357!!!

 

[Hardcorist]

dealt the finishing touch to give exclusivity
http://player.ru/showthread.php?t=67244&page=455&p=954753&viewfull=1#post954753
 
for some reason I can not attach a picture

 

[AlexRoma]

Teclast T51 mod done..
 
Stock OPA2604 line-out opamp repalced with LM6172 opamp.
Stock defective invertors were replaced with good ones. 
 
The results are not dramatic, but their main goal has been achieved - no more distortion on every EQ preset. 
 
You can see the T51 RMAA result, before and after right here : rmaa.hostei.com
 
Some more comments on sound changes..
 
The signature became less analytical but still far away from analogical type of sound (hello Wolfson). The bright and digital treble presentation is still there but the bass gained more quantity (about 3~4 db more). The mids, I think, were also brought a little upfront (+ 1~2 db). Now, the signature is more pleasant then before, and I can use Normal EQ, with my VSonic GR07 (which are also analytic studio earphones). There are no other substantial quality improvements in the sound. The bass is still kind of mellow, soft, flabby (I suppose it's an internal amp issue), the mids sound great, trebles are still digital and synthetic. 
 
If you ask me is the mod worth the effort, the answer is definitely Yes. No more distortion, and far bigger amplification reserve + even better synergy with armature earphones (more bass quantity). 

 

[glassmoon]

Quote:

Teclast T51 mod done..
 
Stock OPA2604 line-out opamp repalced with LM6170 opamp.
Stock defective invertors were replaced with good ones. 
 
The results are not dramatic, but their main goal has been achieved - no more distortion on every EQ preset. 
 
You can see the T51 RMAA result, before and after right here : rmaa.hostei.com
 
Some more comments on sound changes..
 
The signature became less analytical but still far away from analogical type of sound (hello Wolfson). The bright and digital treble presentation is still there but the bass gained more quantity (about 3~4 db more). The mids, I think, were also brought a little upfront (+ 1~2 db). Now, the signature is more pleasant then before, and I can use Normal EQ, with my VSonic GR07 (which are also analytic studio earphones). There are no other substantial quality improvements in the sound. The bass is still kind of mellow, soft, flabby (I suppose it's an internal amp issue), the mids sound great, trebles are still digital and synthetic. 
 
If you ask me is the mod worth the effort, the answer is definitely Yes. No more distortion, and far bigger amplification reserve + even better synergy with armature earphones (more bass quantity). 

great to hear/read that... since it is far less complicated then the "spaghetti master yoda mod" and the distortion is my highest concern i might try it. the rmaa also looks very promising. thx for the sharing Alex.
 

 

[w357]

Good work!

 

[AlexRoma]

I am sorry for a small mistake : Stock OPA2604 line-out opamp repalced with LM6172 opamp.

 

[TheMaestro335]

This thing is the biggest piece of CRAP!!!!! 2nd unit, stopped working after a month. CHEAP CHEAP! Save your $