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    Building, troubleshooting and testing of these amplifiers should only be
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6e2 Magic eye datasheet

Hi

Does anyone have a data sheet for a 6e2 aka Magic Eye tube? I'm trying to work out how to increase the visual dynamic range of the magic eye tube on this 6H30 preamp I recently purchased off ebay from HK. It's wired in like a "VU Meter" so the bars dance around as the music plays - way cool!

At steady state (no input signal) the bars are already 50% lit up.

I've looked for a data sheet at the usual suspects (Duncan Amps, Google etc) with no avail.

I have the schematic but it was too big to attach here - if anyone wants a copy just PM me.

Great sounding preamp by the way (buckets of drive and dynamics) and inexpensive to make. Board off ebay was about $100US delivered. Transformer and stepped attenuator added about another $150US and I have current recycled an old box for the chassis ;)
 
Silver Stealth said:
Thanks for the very useful links - I never realised there was such a variety! :bigeyes:

My 6e2 looks quite similar to the EM840 type having the two vertical bars one above the other.

Is it normal to have the bars 50% lit with no signal? I would have thought not.


If you are talking about Lite Audio LS32 I have the same preamp and it behaves the same way.
Do you find that the tubes tend to be microphonic? Mine are Sovtek 6H30 .... and seem to be terribly microphonic.

Cheers

Andrea
 
Here is the schematic:

I'm also a bit dubious about the output cap, that seems quite small...

Cheers

Andrea
 

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johnmarkp said:
Two questions on this preamp. How big should the caps be for the output? Also can the gain be lowered easily?

Depending on the input impedance ot the following amplifier you might have to increase theri value.
I used 2* 2.2 uF MKL that I had handy.
I'd say use the best capacitors in a 1-5uF range that you have (with the correct voltage rating)

To lower the gain you can remove the cathode bypass capacitor.

Regards

Andrea