I heard of this little headamp through mention on an audio forum, so I thought I would take a punt and try it out. Packaged in a very neat black extruded aluminium case, the headamp sports RCA phono connectors for the input and output on one side of the case and on the opposite side, an on-off switch, indicator LED and socket for connection to the 12VAC ‘wall wart’.
The cartridge used was an unmodified Denon 103 and the Little Bear headamp fed the DISC input of a Quad 44 preamp (sensitivity set to 3mV), connected by a pair of 1m length RG-223/U-01 cables.
At only £20 I wasn’t expecting too much, but I have to say I was very pleasantly surprised by what I heard. Until now I have been using a Linn LINNK phonostage (actually made for Linn by Naim Audio and based on the circuit of the Naim 323 boards) or either a Mark Levinson ML-25 phonostage or a Mark Levinson ML-10A preamp. All of the latter are considerably more expensive than the Little Bear T8-1!
OK, the Little Bear doesn’t trounce any of the above devices, nor would I expect it to, but it does sound very good indeed and for the price astonishing. I played Dire Strait’s eponymous LP: all the subtlety I associate with this album as well as the tight, driving, rhythm were there. Next up was Linda Ronstadt’s ‘Hand Sown, Home Grown’, a good test for treble control, as Ronstadt’s voice can sound hard and edgy if there are problems in the replay chain. The Little Bear sailed through this hurdle easily. The sound stage is not as deep as that with either the Linn or the Levinson designs, and the treble can at times, ‘shout’. But for £20 it’s a fantastic bargain!
A Closer Look – Under the Hood
Being an inquisitive person I just had to take a peek inside, to see what £20 bought you. Not surprisingly the circuit is simple – dead simple: just a single transistor (marked as K184 (a BC184 perhaps?)) per channel, drawing a collector current of ~2mA.
The input to the base of the transistor is via a single Elna 470uF coupling capacitor, followed by a shunt 680Ω resistor. The emitter resistor is 1kΩ, bypassed with an Elna 470uF capacitor and the output is taken directly from the collector.
Raw 12V AC from a ‘wall wart’ is rectified by a bridge rectifier and then smoothed by a 200uF electrolytic, itself bypassed with a 100nF capacitor. This in turn feeds a linear voltage regulator using a 12V Zener diode reference. Hum and noise is commendably low, but of course, not as good as with either the Linn or the Levinson amps. Switch spikes are not as well suppressed as they are with either Levinson product (which appear to be totally immune to switch spikes) – in fact they are quite bad (but then so too is the Linn LINNK in this respect).
Such a simple circuit has no right to sound as good as this. With a little fettling, such as perhaps upgrading the input capacitors in the signal path, and replacing the Chinese sourced 200uF caps in the power supply, the performance could well be further improved. However, as it stands, this little device represents excellent value for money and is to be commended.
So if you want to try out a moving coil cartridge but your amplifier is only equipped with a fixed-coil input, the Little Bear T8-1 headamp can be recommended to get you started.
Source of review item – End User Purchase
Retail Cost £20 + P&P
Manufacturer – Little Bear Audio http://stores.ebay.co.uk/littlebearaudio
Mr. GuangWei Xie
|Street Address:||futian block.bi hao garden b-402|
The published specification for the Little Bear T8-1 head-amp is as follows:
Step up ratio: 1:10 (i.e. 20dB)
MC input support: Moving coil cartridges 0.3 – 0.8mV, impedance 20 – 100Ω
(this I take it to mean the amp will be suitable for those MC cartridges requiring a loading of 20 – 100Ω)
Output: 3 – 8mV, impedance 47KΩ
(i.e. the RIAA equalised input of the preamp will have an input impedance of 47kΩ)
Frequency range: 20 – 20,000Hz +/- 0.5dB
Distortion: < 0.1%, 1kHz
Power: 12 – 18VAC, 100mA
© Text Copyright and all photos 2015 Barry Hunt, except album sleeves. Copyright there, belongs with the named party.
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