‘Little Bear’ Moving Coil Step Up Preamplifier T8-1

[Barry]

‘Little Bear’ Moving Coil Step Up Preamplifier T8-1





Prompted by Ali Tait’s mention of this amp, I thought I would take a punt. It arrived today, so I plumbed it into my system. The cartridge is a ‘cooking’ Denon 103 and the headamp feeds the DISC input of a Quad 44 (sensitivity set to 3mV), connected by a pair of 1m RG-223/U-01 cables.



At only £20 I wasn’t expecting too much, but I was very pleasantly surprised by what I heard. Until now I have been using either a Linn LINNK phonostage (actually made for Linn by Naim and based on the circuit of the Naim 323 boards) or either a Mark Levinson ML-25 phonostage or a 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 sublety 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. 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 bloody fantastic!


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.





A single Elna 470uF input coupling capacitor is followed by a shunt 680Ω resistor. The emitter resistor is 1kΩ, bypassed with an Elna 470uF capacitor. 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 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 VFM and is to be commended.


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
(by 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

[Ali Tait]

Good stuff Barry, not got round to trying mine yet, too busy fettling the Denon.

As you say, better caps and maybe resistors too would be worthwhile.

[Box13]

For what one pays for the Little Bear products, they are remarkable.

[Ali Tait]

A better power supply would probably be worthwhile also.

[Barry]

Good stuff Barry, not got round to trying mine yet, too busy fettling the Denon.

As you say, better caps and maybe resistors too would be worthwhile.

I would be interested to learn of your findings. I would expect your Denon to offer superior SQ, but then I expect it cost somewhat more than the Little Bear.

However, you may be pleasantly surprised by what the T8-1 can offer for such little outlay - I was.

[Ali Tait]

I have gone further with the Denon, replacing all the ceramic and tantalum caps also. Best I've heard from my vinyl set up to date. Compared it before doing this at a friend's house to an S & B SUT (costing four figures), with which it was thought to have a little different but equally good sound. Great result given the cost.

Time to check out the Little Bear now.

[Box13]

‘Little Bear’ Moving Coil Step Up Preamplifier T8-1





Prompted by Ali Tait’s mention of this amp, I thought I would take a punt. It arrived today, so I plumbed it into my system. The cartridge is a ‘cooking’ Denon 103 and the headamp feeds the DISC input of a Quad 44 (sensitivity set to 3mV), connected by a pair of 1m RG-223/U-01 cables.



At only £20 I wasn’t expecting too much, but I was very pleasantly surprised by what I heard. Until now I have been using either a Linn LINNK phonostage (actually made for Linn by Naim and based on the circuit of the Naim 323 boards) or either a Mark Levinson ML-25 phonostage or a 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 sublety 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. 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 bloody fantastic!


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.





A single Elna 470uF input coupling capacitor is followed by a shunt 680Ω resistor. The emitter resistor is 1kΩ, bypassed with an Elna 470uF capacitor. 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 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 VFM and is to be commended.


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
(by 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

I have never owned any Quad gear, but those that do seem to be satisfied.
Do they persist with the Fischer-Price look or is yours a vintage unit?

[Gordon Steadman]

I have never owned any Quad gear, but those that do seem to be satisfied.
Do they persist with the Fischer-Price look or is yours a vintage unit?

Best ignored I think.

[mikmas]

I have never owned any Quad gear, but those that do seem to be satisfied.
Do they persist with the Fischer-Price look or is yours a vintage unit?

Unfortunately the coloured buttons were phased out decades ago and replaced by uniform grey units.
The early models are indeed like Marmite but personally I love them - as did the UK Design Council.
(I also love Marmite though ....

[Box13]

Unfortunately the coloured buttons were phased out decades ago and replaced by uniform grey units.
The early models are indeed like Marmite but personally I love them - as did the UK Design Council.
(I also love Marmite though ....

I could live with anything if I liked the sound Mike.
Can you remember when all N.A.D buttons looked like Tootie Fruities?