New SE With Triode Mode KT120/150

[Cressy Snr]

Aye, valves can be contrary b’stards.
These Brimar EF80s however, sound very good in triode mode. They are smooth and detailed, nicely complementing the 807 output stage.

[steve s]

When I 1st bought a few boxes of valves back in the 90s there always seemed to be loads of ef80's, so I used to throw them out ! At the time probably 30 or 40 of them
And that was on good advice from a valve dealer friend too..

[steve s]

when I triode various ef86s I found them slightly bass light, it will be interesting to hear your findings Steve with the ef80, maybe I chucked the wrong valves..

[Cressy Snr]

when I triode various ef86s I found them slightly bass light, it will be interesting to hear your findings Steve with the ef80, maybe I chucked the wrong valves..

Hi Steve,
The EF80s don’t seem to have curtailed the bass end; not in my system at any rate. It’s a nice, clean, wide-range sound.

[Greg]

It’s worth remembering that the ECF80 has always performed (apart from voltage fluctuation) admirably in the WAD/WD KeL84.

[ed]

I was just trying to reaquaint myself with this valve malarky...
but I'm struggling with the comparison of ef80 and ecf80
according to my brimar manual the pentode side of ecf80 doesn't match the ef80

am I missing something fundamental?

[Nick]

No, they are different valves.

[Mike H]

Maybe only from the point of view that they're both radio IF pentodes? Yet can work well for audio.

[steve s]

Hi Steve,
The EF80s don’t seem to have curtailed the bass end; not in my system at any rate. It’s a nice, clean, wide-range sound.

Thats good news Steve, looks like I dumped the wrong valves..

[Cressy Snr]

Hi Steve,
The EF80s don’t seem to have curtailed the bass end; not in my system at any rate. It’s a nice, clean, wide-range sound.

Thats good news Steve, looks like I dumped the wrong valves..

Sorry about that Steve.

[Cressy Snr]

I know I said it was a wrap when I last posted the circuits, but today I’ve been on quite a big simplification mission.

To be honest, I don’t think an overkill twin power supply setup is justified in this particular 2W instance, so I’ve emptied the inside of a 6V heater transformer and the outside, of a 200VA, toroidal mains transformer. The mains switching has been redone and a general clean-up was carried out.
The preamp stage gets the benefit of the power stage smoothing, so the SNR is improved over the twin PSUs. It all sounds perfectly fine.

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[Cressy Snr]

Managed to find a few more EF80s in another of my boxes. I’m pretty well set up for them now. Just need to get hold of a couple more 807s. Both of these valve types are pretty cheap to buy at the moment.
Every once in a while you stumble across a combination that works way too well, considering what it is made of. I guess that’s what’s happened here.

[Cressy Snr]

And round we go again, circling back to the start of all this valve malarkey in 2005.
So I've once again ended up going back to triode mode EL34s. It would seem that the EL34 is my favourite valve of all time, trumping everything else I've ever tried. It is the best sounding, indirectly heated output valve on the planet: for me at least it is. I can't keep denying it. I love the bloody thing. It provides me with what I want out of a valve amplifier and it's my ears and those of the missus, I have to please, nobody else's.

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As soon as the first bars of 'Last Train Home' by Pat Metheny struck up, the missus said, 'that's it, that's lovely, and we both relaxed and let the music flow.
With the triode strapped STC/Brimar EF80s driving them, the TAD EL34B-STRs sound the best I've heard them. Compared to KT66, KT77, 807, KT120, 7581A, 6550, there's no contest. Those beam pentode valves are just not in the same league. I couldn't give a fook what anyone else says. There must be a reason why I always come back to the EL34 and I'm done with trying to be intellectualise it. EL34s speak to me on a level that nothing else does, and for this listener, there's nothing that even comes close. Bugger it. I've done with the rest of the power valves. It is what it is.
Last schematic and I really do mean it:

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.

[Greg]

Now you’ll have to dig the garden

[steve s]

Looks great Steve.. who would have thought you be back to el34's... not me !