Little bear tube phono preamp - anyone has it?

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This is the one I have. Very Quiet, and I like the sound very much. Just look for "6N3 Tube Preamp" on eBay.
 

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Hey guys

i saw this little guy online:

Little Bear Tube Valve Stereo Phono Turntable RIAA Preamp Preamplifier Amplifier | eBay

and was wondering if anyone tried it yet.. i guess ill order it anyway and give my input on it later, but i hoped some one allready tried it.

what do you think?

Hi Tankpopper,

Mine just arrived last week.
It had the bottom perspex plate kind of cracked probably due to mechanical stress during shipping.
The seller seems very kind and promised to send another one.
Do not expect a schematic inside. There is none. He sent me by email a pdf but it's full of mistakes. I manually extracted the schematic and will post it soon.
It sounds pretty good for the money. I don't have professional equipment to test the RIAA curve response.
The one and only thing that you MUST do is SHIELDING!
I covered all the electronics and the first tube in aluminum foil and now I can turn my 100W amplifier to max with Little-Bear phono preamp connected and it's (almost) dead silent :). I'll post a photo soon.
 
Hello Tanktopper,

Just received the Little Bear tube phono preamp. Assembly was fairly easy based on the pics, however not sure if I have the blue/black wires in the right connectors. Overall it sounds pretty good but I'm getting slight hum (with ground connected). Do you have schematic you could forward, post or send to me? Also, I tried loading your shielded pic above, it just hangs. Would love to see and or hear any tweaks you did on this unit. Thanks!
 
I don't know what the deal is with hum with preamp tube circuits. I built tube type electronic crossover and just couldn't get the hum problem whipped. I altered the circuit to take JFETs instead of tubes. No more hum and it sounded better. I understand the fascination with tubes and one can be forgiven for thinking that tubes are ALWAYS better, but I have found JFETs do a better job with the low-level audio. Tubes are noisy. The signal coming from a turntable is tiny. It is going to be problematic to say the least amplifying that tiny signal without tube noise being audible. JFETs would do the job much better, have more gain, sound like tubes anyway, and have WAY less noise.
 
trying to set up this new version of the bear and am getting no music, just a bit of hum and it seems the little gz4 tube is not lit up. the other three 12ax7's are lit....any ideas?

Check rectifier pins 3 & 4 for voltage. If you get a voltage reading, then most likely the tube is a dud, if it's not lighting up.

I don't know what the deal is with hum with preamp tube circuits.

This particular design is very prone to hum, which is well documented in the AK thread.

jeff
 
I didn't receive any schematics either, and haven't heard back from the seller yet either.
The transformer printing reads both red leads are primarys.
One has a white tape marker attached, with no printing on it.
Does it matter which wire goes to the circuit board clamps labelled 220v or 110v?
Every picture I've found show one red lead going to each . Not sure if it matters on the 2.6 version, with the toroidal transformer.
Thanks anyone, for help!
I don't want to let any smoke out.
 
Start Me up

Thanks for the advice, Little Bear is now Running Bear.
Wasn't sure I wanted to return to tubes, last year I went back to solid state amps.
It's a really nice preamp: rounded as in 3D sound, solid imaging, even-handed at resolving details at all frequencies I can hear.
Haven't tried it with the stock tubes, I had some reissue Mullards, NOS RCA, and JJ 12AX7 trios at hand.
Sounds best all around in my setup with a Nagaoka ML110 cartridge.
A bit less "hifi" sounding than my 551P, and Sumo Athena, maybe a little more natural than either.
 
if you search there is the little bear with tube screens and toroidal transformer also needs smoothing circuit after the transformer as well
400982973467

Can you provide a link please?
I noticed there was some hum; it went away when I moved the unit up about 8 inches from my preamp.
I wonder too, if I'd hear any benefit from moving the transformer out of the case, further away from the tubes.
I'm using a 35 year old turntable, when one of the channels quit, it was just a bad plug.
I took the time to replace the not bad looking leads with shielded mic cable , almost zero hum now, and my Sumo preamp has plenty of gain in active mode!
 
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