Maybe this would be fixed with a different potentiometer? Could be really easy and cheap to fix, talk to the manufacturer.
It doesn’t use a potentiometer but uses photo cells. Changing this means you might as well get a different pre.
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Plenty of scope for tube faff…
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Decware are where I’m headed!
Fingers crossed.
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There’s more than a few good ideas involving tube power plus preamps with, including but not exclusively, 300Bs etc. Lots of choice in this space in the market too - Mayer, SJS, Thoress, Aurorasound and many more.
Different tubes, different circuits etc so I imagine they might also sound quite different to each other which makes choosing one a tricky process because you’ll never be able to audition all of them with your speakers.
I do know how the Preda sounds though and if the Pada 300b are anywhere near as good that would be very promising indeed - @murrayjohnson did you ever get a pair in to listen to yourself and is the rrp about £16k for the pair?
Personally, I think these SIT amps could be perfect: DIY - SIT amps
For most speakers, the high Zout means the bass can be a bit loose (like most 300B amps). With AG’s this is a non-issue due to the active bass.
They are low gain and should be very quiet (my similar one was, which @Wayward has now for his mid horns).
It won’t sound like a 300B amp (less rose tinted) but that may be preferable.
The downside is it’s not a shiny blingy box 
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I looked at those earlier when thinking about SIT amps.
Only if you define high end by price. That has £3-400 in just the components and many a jfet. A retail product would be £££
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It’s impossible to say for certain, but maybe Rob would let you try them? You’d probably want a pre with a bit of gain as the power amps will have very little.
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I suspect they would tick a lot of the boxes in the description above
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That’s what I meant!
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I borrowed them from Rob just didn’t have enough for the primes. They are bloody heavy though I warn you.
Yes, not surprised with the Primes, they need a higher damping factor, hence the one I built for @pmac (and @chelseadave, which is a hybrid version) which has transformer coupling to get the output impedance down and a gain stage to compensate for the loss of gain. Paul did find the same as you with the original one I built which is similar to Robster’s versions.
But AGs are active in the bass so this is not an issue.
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Quirky and very nice.
I hope you find satisfaction which involves keeping that. An interesting chap Hervé Delétraz,
he has great taste in speakers.
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Cymer Southern Stars 35 se Power amps.
https://6moons.com/audioreviews/cymer/1.html
I have a pair in the bedroom. Nice.
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Well with much thanks to @RobsterD @thebiglebowski and @octh the SIT amps should be winging their way to me next week 
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Shit I’d better dust ‘em off !
Just plumbed them in - I still like them
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I think he’s broadened his demo range but yes he likes Redhekos
A few years ago on a wild wet night I went half way across Glasgow to buy a Yamaha B-2 VFET amp to be greeted by Robert who said I just plumbed it in and you know I still like it. The cunt changed his mind and refused to sell me the amp. I’m still angry.
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