[MIKELAP]

  That akward moment when your portable tube amp has a wider soundstage than your solid state as well as having an overall better performance....

Been debating getting the usb charging model or the $60.00 power supply model would use it with 16 ohm buds The main question is ,.is this amp worth buying in your opinion ,hows the build quality.Whats the battery life like on this amp 2-3 hours or more 

 

[AudioNewbi3]

  Thanks.  That's odd that it lists max load of 200 ohms.  On Amazon they list 16-400 ohms, but yeah on ali and taobao they list 16-200 ohms.  Power output is listed at 450mW, but doesn't specify the load they are using to achieve that.  
 
If you ever get a chance to test with the Seahf 320's let me know! I'm very interested.

 
Will do.

  Been debating getting the usb charging model or the $60.00 power supply model would use it with 16 ohm buds The main question is ,.is this amp worth buying in your opinion ,hows the build quality.Whats the battery life like on this amp 2-3 hours or more 

Build quality is solid. At least my B4 is. If I were you I would get the DC charging version as the noise floor is significantly reduced due to the simplified PSU.
 
As for battery life for my B4,  official Taobao store quoted an operating time of 3~4Hours. Tube will get warm but not hot.

 

[gwompki]

use this with Seahf LD3.0 400 Ohm, normal

Golov, how is the performance of B4 with high impedance ear buds. I am interested in Zen 2 and Seahf 320 ohm.

 

[AudioNewbi3]

Golov, how is the performance of B4 with high impedance ear buds. I am interested in Zen 2 and Seahf 320 ohm.

Think he is double amping, using one amp for power whilst the B4 mainly for sound change.

 

[golov17]

in fact, it has enough power to run nearly 400 Ohm at maximum volume

 

[AudioNewbi3]

  Thanks.  That's odd that it lists max load of 200 ohms.  On Amazon they list 16-400 ohms, but yeah on ali and taobao they list 16-200 ohms.  Power output is listed at 450mW, but doesn't specify the load they are using to achieve that.  
 
If you ever get a chance to test with the Seahf 320's let me know! I'm very interested.

 
So I tried it with my SeaHF V1 320Ohm today and I must say, the amp did struggle to drive them on my normal Xuduoo X3 settings (RB'ed).
My normal LO volume is -25db and with this the volume knob of the b4 had to be turned to 12 oclock to drive the 320Ohms
Switching the LO volume to -15~-10db solved the issue and the volume pot can comfortably sit at 10 o'clock to drive the 320Ohms. 
 
Maybe due to placebo effect, I did think the lower end sounded a wee bit "muddied"

in fact, it has enough power to run nearly 400 Ohm at maximum volume

Your's is the b3 whilst mine is the b4 so I think there maybe some difference mate!

 

[gwompki]

Thanks for the impressions!  They are much appreciated.  It sounds like even though it might not be ideal, overall the amp will probably meet my needs.  Great news.  I think I will order today.

 

[AudioNewbi3]

  Thanks for the impressions!  They are much appreciated.  It sounds like even though it might not be ideal, overall the amp will probably meet my needs.  Great news.  I think I will order today.

No problem mate

 

[Maxx134]

Got my Little Bear B4 today. I am positively surprised. Its quite good actually, after a few minutes warm up. I consider it an update to the stock X3 amp with a quite likeable, warmer sound signature, even with the default opamp. It is not getting hot either, so no problem handling it.

Edit: woops sorry I have B3 unit:

I have updated my B3 opamp and noted improvement.
Although it is not as powerful as my O2 amp, I still like the sound better.
The O2 need to have it's op-amps rolled to sound optimal.

Although I love the B3, I like to test the newer units so anyone like the B3 PM me.
Edit the B3 has the USB charging ,
While the B4 has normal charging.
B5 look nice but obviously weaker.

Also, I believe all these units can have their opamps swapped for more sonic options.

 

[MIKELAP]

  Regarding the B4 any distortion issues if over driven 
Pros: Transparency, build quality, portability, use with iOS (special cable required), DAC resolution, sound quality, aesthetic appeal
Cons: Valves distort if over driven (line in source needs to be variable), low powered for higher impedance cans, no way to turn off USB charging.

 

                                                                                                                                                                                                                                                                                                                                   

 

[gwompki]

I ordered the B4 yesterday. Now the 2-3 week wait begins. Looking forward to experimenting with it. Looking forward to opamp rolling and building a module to make tube swaps easy(ish).

 

[bzfrank]

Yep, matches my experience:
 
B4 Pros:  
 
- Sound is good (for low impedance headphones/IEMs and moderate levels)
- Amps can be easily rolled
- Price
- Nice glow
 
B4 Cons: 
 
- Click noise when turning on/off
- Limited RF resistance (mobile phone transmissions are audible when stacked)
- Limited Power (cannot drive high impedance headphones), distortion when over driven, variable source needed
- Need separate 12V charger

 

[gwompki]

My B4 arrived today. Initial impressions are really good. Much smaller than anticipated. Packaging is very minimal, but who cares.


After 2 hours of use here is what I can say confidently.

-much smaller and lighter than I expected
-powering 320 ohm ear buds (Zen 2.0) with authority
-unit is slightly warm after an hour but definitely not hot
-rf interference is minimal. I have my phone back to back with the the b4 right now and do hear some noise between tracks but not much. Move it slightly and it's gone entirely
-battery life seems good so far but only 2 hours in.

I am impressed so far. Can't wait to roll op amps and listen more.

 

[MIKELAP]

My B4 arrived today. Initial impressions are really good. Much smaller than anticipated. Packaging is very minimal, but who cares.


After 2 hours of use here is what I can say confidently.

-much smaller and lighter than I expected
-powering 320 ohm ear buds (Zen 2.0) with authority
-unit is slightly warm after an hour but definitely not hot
-rf interference is minimal. I have my phone back to back with the the b4 right now and do hear some noise between tracks but not much. Move it slightly and it's gone entirely
-battery life seems good so far but only 2 hours in.

I am impressed so far. Can't wait to roll op amps and listen more.

Any distortion if overdriven ? 

 

[gwompki]

Any distortion if overdriven ? 

So far my phone has not been able to make them clip at max volume. Im guessing if I had a real dap with more power I would be getting some clipping.

On the opamp front so far I have tried two others than stock:

LM4562 - made everything waaay too warm but pretty good sounding regardless. I feel like some of the dynamics might have been lost.

Opa2107 - slightly warmer than stock. Better overall dynamics. Both lows and highs sound much better. Highs not as shrill. Really like this one.

I plan to try a muse02 and opa2134 soon, but letting my ears adjust to opa2107 first