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Lawrence001
03-03-2018, 21:34
I don't really know anything about this except that it is a diy job, it has a very heavy chunky walwart PSU (French plug) and it takes an ECC83 valve. The attenuator is notched but I think it is a standard potentiometer rather than a stepped one. There is a 2 way switch at the front to change the gain, I'm not sure if that is variable gain or feedback. I'd like to think it's not a switched mode PSU given the size and weight but again have no idea, it has a switch that lights up when it's switched on.

I've used it on and off for several years both as a pre amp in my second system and a "buffer" in my main and headphone systems by setting the gain at unity. It gives the music a definite valve flavour. The gain switch seems to make it sound more full bodied and weighty at the high setting but that could just be me not accurately changing the volume level accurately to compensate. At the high setting the unity gain is around 10 o'clock whereas it's nearer 12 at the low setting, so it's quite high gain (as you'd expect with a 12AX7).

No idea what it's worth, so say £35 plus postage with a Chinese valve (not the Mazda valve shown in the photos). https://uploads.tapatalk-cdn.com/20180303/5c80c4779bd6ae3466421f2ce90e1e84.jpghttps://uploads.tapatalk-cdn.com/20180303/56790cbfda734312f53f9f99ed917703.jpghttps://uploads.tapatalk-cdn.com/20180303/3d4d6f6c441cf39f596e97aa59ea05d7.jpg

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donmarrese
03-03-2018, 22:00
I'll take it Lawrence..

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Lawrence001
03-03-2018, 22:03
No problem Don would you like me to post it (probably small parcel RM tbc) or would you prefer to collect?

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montesquieu
03-03-2018, 22:50
Bummer I was just about to post a WTB for one of these for use with my phono re-equaliser :(
farflungstar
03-03-2018, 23:01
Bummer I was just about to post a WTB for one of these for use with my phono re-equaliser :(Ditto
Lawrence001
03-03-2018, 23:14
How about those Chinese ones that go for about £40 you can't go much wrong with them with some better valves (which I may have in my collection of spares).
montesquieu
03-03-2018, 23:17
Just looked - yes a few options there. Used to be nothing for under £100 or so. Under £40 is reasonable for an experiment :)
walpurgis
03-03-2018, 23:27
The Chinese valve buffers tend to be 'clones' of the original Musical fidelity X-10D. Which I actually like a lot. It works very well in the right situation.
ovlov854
04-03-2018, 01:38
The Chinese valve buffers tend to be 'clones' of the original Musical fidelity X-10D. Which I actually like a lot. It works very well in the right situation.

I would have suggested the X-can.....should be inexpensive now
Lawrence001
04-03-2018, 08:10
I would have suggested the X-can.....should be inexpensive now

That's the headphone amp version of the x10d buffer so not designed for this task. Though it could be used at a push with a jack to rca cable.
donmarrese
07-03-2018, 19:26
Hi Lawrence
Just plugged the little beast in, wacked a Mullard ECC83 Yellow on it ...and I must say, It sounds a hell of a lot better than those Little Bear buffers.
Over the last year, I've steered away from valve kit, embracing Transistor/Mosfet pre/amps... but little thing has re kindled my flame for valves...
Excellent buy, well pleased. Thank you.
Lawrence001
07-03-2018, 21:20
Glad you like it, looking inside and seeing just a few resistors connected to the valve reminded me of the circuit of my old croft micro so not surprised you like it. If you can live with the relatively high gain of the ECC83 then you can't really go wrong.