[povidlo]

Folks, I wrote a straight-forward review for Little Bear B4-X's popular simple mod with silicone o-rings and Burson V6 Vivid opamps.

Enjoy the read: https://www.head-fi.org/showcase/little-bear-b4-x.25234/reviews

 

[cpu235]

Just upgraded mine with Burson V5i and the soundstage is significantly wider! IMO the upgrade is worth it, the only thing I hope to improve is the clarity but for the price and portability it is nice.

 

[triggrhaapi]

Just upgraded mine with Burson V5i and the soundstage is significantly wider! IMO the upgrade is worth it, the only thing I hope to improve is the clarity but for the price and portability it is nice.

What's your source? I am using my LG G7 and I don't have a significant change to clarity between this exact setup and my Monolith AAA dac/amp.

 

[cpu235]

What's your source? I am using my LG G7 and I don't have a significant change to clarity between this exact setup and my Monolith AAA dac/amp.

I usually just pair it with my iPhone 11 or with my Fostex HPA4BL and it sounds a bit less clear but overall not huge change to clarity. But the soundstage improvement is great.

 

[rprodrigues]

@DBaldock9
Have you used the mini tube sockets you bought some time ago?

 

[DBaldock9]

@DBaldock9
Have you used the mini tube sockets you bought some time ago?

No. I've been working on other projects.

 

[sfrsfr]

I would like to share with You with my last foundling. Zishan is famous from good cheap portable DAPs. He create also super compact and ultra cheap tube amplifier AD3.

Device is not a perfect from factor but with little attention can be really impressive.



- Removed blocking output caps (big improvement)
- USB-C port with fast charging
- OPAMP replaced to OPA1612

So I got the AD3 as well and it looks quite different inside. I wonder if replacing these caps improves the sound much as well...

 

[Setmagic]

So I got the AD3 as well and it looks quite different inside. I wonder if replacing these caps improves the sound much as well...

This is a version from 2021 it has a little better amount of capacity for tube filtering and probably better design.
There is no space as well for bigger caps, so it is hard to modify.
To bad, It's still microUSB for charging.

 

[sfrsfr]

This is a version from 2021 it has a little better amount of capacity for tube filtering and probably better design.
There is no space as well for bigger caps, so it is hard to modify.
To bad, It's still microUSB for charging.

Yeah, not much space left. Maybe replacing the blue caps with gold Nichicon would have some positive effect?
The first pic is already with replaced opamp - Muses 02.

 

[Setmagic]

Yeah, not much space left. Maybe replacing the blue caps with gold Nichicon would have some positive effect?
The first pic is already with replaced opamp - Muses 02.

You don't have space to replace for Nichicon Fine Gold (FG) series who is higher grade than (FW). I don't think this Panasonic is worse than generic Nichicon (FW). Main problem of previous 19/20 y versions was too small power capacitance in 30V rail for tube. For opamp you need 25v for tube at least 50V better caps are bigger and can't fit.
If you really want to try to improve filtering you can place smaller caps in parallel of this ones. Just buy Nichicon FW 2x 47uF 50V and 2x 100uF 25V. If they don't fit just make space by removing little bit of this foam from battery.
Watch out for shortcuts and polarity of caps becouse I'm sure they can explode.

 

[sfrsfr]

You don't have space to replace for Nichicon Fine Gold (FG) series who is higher grade than (FW). I don't think this Panasonic is worse than generic Nichicon (FW). Main problem of previous 19/20 y versions was too small power capacitance in 30V rail for tube. For opamp you need 25v for tube at least 50V better caps are bigger and can't fit.
If you really want to try to improve filtering you can place smaller caps in parallel of this ones. Just buy Nichicon FW 2x 47uF 50V and 2x 100uF 25V. If they don't fit just make space by removing little bit of this foam from battery.
Watch out for shortcuts and polarity of caps becouse I'm sure they can explode.

What about the green Nichicon MUSE ES? Would they be a good replacement?

 

[Light - Man]

Just upgraded mine with Burson V5i and the soundstage is significantly wider! IMO the upgrade is worth it, the only thing I hope to improve is the clarity but for the price and portability it is nice.

Hey guys, is there a consensus that Burson V5i is the best option that fits inside the case of the Little Bear B4?

Is the upgrade really worth the cost, delivery time and the hassle to change over the stock op-amp?

BTW, I clearly preferred the basic B4 over the B4X, when I compared both directly, but only compared them during single ended use. I also noticed that the B4X was clearly noisier.

 

[Setmagic]

What about the green Nichicon MUSE ES? Would they be a good replacement?

They are Bi-Polar type of electrolytic capacitor, and it's useless for that kind of application.
They just contain 2 polarized (+/-) capacitors inside one housing. Too big for a reasonable capacitance in that case.

 

[Mouseman]

Hey guys, is there a consensus that Burson V5i is the best option that fits inside the case of the Little Bear B4?

Is the upgrade really worth the cost, delivery time and the hassle to change over the stock op-amp?

BTW, I clearly preferred the basic B4 over the B4X, when I compared both directly, but only compared them during single ended use. I also noticed that the B4X was clearly noisier.

Yes, I think it's worth the cost if you can swing it. It's not really much hassle to install at all. SQ is definitely improved over the stock units.

 

[sfrsfr]

Grade of quality and amount of uF in rail.
Most differences causes change this white caps on the top (left corner) to red WIMA 5% and capacity(right side) for Tube supply.
2 x220uF 63V paired with stock 100nF V50
Stock Capacitors Vs Nichicon Fine Gold.
Muses was for opamp supply just in case but do not give any improvements.


Final project ready to close in case.
Nichicon Fine Gold 50V 147uF (100+47)

Any advice on replacing the original white caps for red WIMA 5%? Would you have a link with more info for the red WIMA 5%?
I wonder if these caps are the same in the 2021 version...