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Quick guide: First: I must tell you that. how is this headphone amplifier design. Actually it's...

Little bear P2-1 GOLD color HiFi valve tube headphone amplifier amp preamp

Rating:
2.75/5,
  • Quick guide:
    First: I must tell you that. how is this headphone amplifier design. Actually it's tube buffer + amplifier work model.both function is alone, the music input to 6J1 tube buffer preamp and output to daul NE5532(TI)(each chip for each channel) amplifier part, after music output to your headphone. else ,In back of the P2-1. you will find a OUT interface. that the 6J1 buffer preamp pure output.you can use it as a buffer preamp for your other power amplifier, that's interface music isn't through the headphone amplifier part.so. it's very helpful for install it in your home audio system too. get more warm sound.
    Secondly: this P2-1 powered by 12VAC, and this list included a transformer already. with both voltage for choice. 110V or 220V,i will sent correct one to you by your order address. Outside shell is made by aluminum, good quality. P2-1 support power to 12~200ohm headphone. so. make sure your headphone is in this ohm range.About the tube.. each tube for each channel. and the tube will light up when turn ON.because there is a LED under the tube. about the tube itself. inside the tube. also will light up. but just weak light. that's normal.don't worry about that.There are 2 headphone interfaces, there are 6.35 and 3.5,Both interface are in parallel connect.so. if you want to get best sound. don't plug 2 headphones in them at same time.



    Parameters :
    Model number : P2-1
    input voltage :AC12V
    frequency response:20 HZ - 20 KHZ
    input sensitivity 300 mv
    SNR: 96 db
    Total harmonic distortion

Recent Reviews

  1. msknight
    Avoid at all costs
    Written by msknight
    Published Aug 15, 2016
    0.5/5,
    Pros - Price
    Cons - Liable to blow caps, missing components and left/right miswired
    It all started with the detection of a bit of noise, which I thought was just some ground/earthing issue, so I continued using it. Also threw away some GE valves because I thought that they were at fault.
     
    Later on, I wanted to test it out a bit further, so ran my test tracks, one of which is the start of a Status Quo track which plays, "There's nothing left," on the right side, followed by, "There's nothing right," on the left side... and back and forth a little. Well, guess what... the P2-1 was wired the wrong way!
     
    On taking it apart to see what I could do, it turned out that two of the 35v 470uF caps had popped. Now, the thing was supplied with an 18v AC/AC transformer, despite the back saying 12v AC. The maker actually said, "
    18V is better for the tube. the heater and other option. make sound more clear." ... Errr..... OK... I'd switched to another 18V AC/AC transformer with a UK plug, rather than using the supplied with the shonky travel adaptor.​

     
    I got in touch with the maker and a replacement came. The left-right issue had been, "sorted," by cutting the tracks and soldering bits of cable across. Ooookkkaaayyyy..... did the job I suppose.
     
    This one too, also blew its caps.
     
    I tried replacing, and re-running... and one of the caps REALLY blew. And I mean it went with a bang and left brown hairy stuff all over the place.
     
    By this time, even after replacing with 50v caps, (and having to cut the cases to pieces to get them in) I was just too scared to run the units. I enlisted the help of a friend who knows her electronics. She was more confident in dealing with the units and straight up, there were components missing! A big resister, and also a capacitor from between the valve sockets. At that point, I gave up on ever getting these working. I've just lost complete trust in the Little Bear range, and what they're doing to the boards.
     
    My boards... (note the larger, 50v caps and missing components)

     
     
     
    E-bay picture... note the extra components...

      B9Scrambler, taffy2207 and ezekiel77 like this.
    1. View previous replies...
    2. MadSounds
      The child who build this one likely was likely too tired or hungry to notice their mistake.
      MadSounds, Aug 15, 2016
    3. thatonenoob
      ohh dearrr.  Thanks for sharing though.
      thatonenoob, Aug 15, 2016
    4. senorx12562
      Thanks for your efforts, and that sucks.
      senorx12562, Aug 16, 2016
  2. bigx5murf
    Shockingly good
    Written by bigx5murf
    Published Jan 15, 2016
    5.0/5,
    Pros - Low noise floor, gets hearing damaging loud, easy to roll tubes ef95/6ak5, feels sturdy, 1/8 & 1/4 jacks.
    Cons - Preamp function only has 1/8" output, AC-AC adapter not easy to find an upgrade, gets warm easily
    These things show up on ebay for a starting price of $0.99 all the time, with like $16 shipping. I managed to pick up my unit for $27 shipped. Shipping was fairly quick as well, 13 days. It came packaged exactly like my little bear p5, but unlike the p5 didn't need any assembly. The specs list a 12v AC psu, but I actually received a 18v AC, same as the p5, but the wallwart was just slightly smaller. This unit doesn't suffer from cellphone/wifi router interference as noticeably as the p5 does, which drove me crazy until I figured out the source of interference. The only headphones I currently own are the AKG k240, and audio technica ath-ad700x, neither are exactly difficult to drive. But the audio technica's have noticeably more gain at the same volume setting. Both sound really great on this amp. I'm feeding the amp with the headphone output of a smsl sd-192 pro dac. I don't have a lot of headphone dac/amp experience though. I mostly prefer to listen through speakers. It definitely sounds better than the headphone amp on my EMU 0404 usb though, especially with vocals. The background is quiet, and there really aren't any real nasties. It works, and works surprisingly good. I have not tried using it as a preamp. This unit also has two NE5532 op-amps, and I may try rolling those in the future.
     
    The cost of this unit is more than worth it. Rolling tubes makes an appreciable difference, and many tubes are available for cheap on ebay. Definitely a fun little device, but with limited utility, it's sized to be a portable amp. But requires AC power, and the tubes stick out. It's a fun toy, especially for rolling tubes and op-amps.
     
    I didn't bother trying the tubes it came with. They're the same as the ones that came with my p5, and those sounded terrible. The tubes from my collection I've tried so far and the slyvania black plates, zenith, and rca chrome plates. Right now I'm really liking the slyvanias for flac, and tidal. But prefer the rca for my needledrops, or turntable. The RCA's do create a really low hum when the gain is turned all the way up. They do that on my p5 as well. I've still got 3 other pairs of tubes I'd like to try. But the ones I've tried so far have been satisfying.
      leobigfield likes this.
    1. leobigfield
      Got one in the same situation as you. I just tried the stock tubes since this is my first tube amp and they did a great job of pushing my Denon D2000! They do warm up and smooth nicely the sometimes cold and piercing denons. I used the D2000 first with an fiio e10 (nice synergy) and now with a fiio q1 that didn't pair up very well so i looked for this amp. I've also bought some voskhod tubes and some lm4562 opamps but they didn't arrive yet. Can't wait to try them!
      leobigfield, Apr 8, 2016

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