I had two visits to Definitive in November and December last year (can’t believe it is a year ago ffs). I was demoing dacs at the time. Kevin did, as Kevin does, start playing with the power amps as well.
One of @sjs Model 5 with LV, then WE, then Tak, then mix a bit with different music.
The WE were the pick of the bunch for me. The Taks sounded more “hifi” ( they are most definitely NOT hifi) compared to the WE. That was, however, in direct comparison, in an unfamiliar system, and with personal preference at that time.
All three sounded like something I could definitely live, and be happy, with.
Oh, and I bought a dac in the end having listened to Thievery Corporation!
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Yesterday spent the afternoon and evening listening to a few choons at @Jim’s.
Upsides #1 - the Art Audio Diavolo 300b Shiny Thing was making very pretty, glittery, shiny 300b noises. Of all the amp’s I’ve heard Jim use, this was the most even-handed across mids and uppers, and although slightly bright occasionally, it made for very easy and pleasant listening: verging into superb with certain pieces. It finally lets the big horns sound something like they ought to. Nice 
Upsides #2 - The Eversolo streamer is a really great-sounding bit of kit, and silly-convenient: I predict in time TT and CDP will be retained solely for decorative purposes! 
Upsides #3 - Ann’s lasagne - NOM! Disappeared too fast for 'photos…
Downsides #1 - that feckin’ sub. Turn it all down Jim! Intrusive. Obvious. No.
To be fair, a tinker with the settings eventually toned it down to a point where it was doing a fair job of integrating with the Gotos, and useully backfilling the low bass…
I suspect what’s needed in that room is DSP-controlled active crossovers for the bass scoops…
Also, this sinister bastard enjoying watching me piss more than is normal -
Downsides #2 - the First Watt J2 sounded shitloads better than all the other stuff we listened to once we’d a) waited nearly an hour for it to warm-up properly from stone cold, left-in-the-truck-outside temps, and b) a spot of faff adjusting horn positions and reducing the gain of the power amp driving the Goto’s bass bins. It sounded so good I thought about changing my speakers for horns - but sadly £££££ says “NO!”, as does Sam… 
What was rather odd was with the J2 driving just the mids and uppers, the bass improved significantly: so much so we were able to switch the sub off altogther for a while, before dialling it in low to extend the low bass. I’ve a theory that there’s some phase-cancellation effect between the mid-upper and bass amplification, which has been robbing the system of bass output and integration. The J2 is non-phase inverting, which IME is quite uncommon.
The downside is Jim didn’t actually really like any of this. 
Strange old business this hifi malarkey, but we all have different tastes 
Downsides #3 - Jim has obtained a listening chair that allows his farting to reach the atmosphere faster, easier, and presumably with fewer friction burns to his balloon-knot:
…a fact he demonstrated with his customary virtuoso trumpet solos… 
Fun day - thanks for hosting mate!
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Realistically I’d give that chair a week, two tops. It lacks the structural integrity needed to withstand the kind of continuous bombardment it’s going to experience. I don’t care how loose a weave it has. Energy cannot be created or destroyed.
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I just hope it’s not his ‘fishing’ chair 
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And then
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It’s a kevlar weave…
…7 months later update. 
Now AN M7 pre. Art Audio Diavolo with Border Patrol PSU fitted with Takatsuki 300b tubes driving the Goto horn arrays and the ES Labs class D Tripath amp driving the GPA bass cabs. SVS SB16 Ultra sub.
Finally found a solution to the slightly unruly upper mid/treble forwardness and sibilance - a Dave Slagle autoformer just in front of the treble horn. (suggested by @coco ) Currently using the -5db tap. This has completely cured the aforementioned toppyness and sibilance.
The system is now sounding far more even and balanced across the entire frequency range. So much so in fact, that it has now enabled me to have the horn arrays pointing more towards the listening position (rather than crossing over in front, as I had it previously)
This has resulted in a further opening up of the midrange which is now sounding even better.
After 18 months of fucking about, it’s now sounding pretty fucking great, yay! 
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Result!
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I have these arriving on Monday with 4 Takatsukis installed. Aurorasound PADA 300B.
Be interesting to see what they’re like and also how the Takatsukis are in my own SET amp.
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Will look forward to your thoughts Guy.
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The croc clips were noted.
Is this going to lead to permanent crossover changes?
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Great result Jim - time for another bakeoff
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Croc clips and no fancy case work, good effort!!
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Are you doing a north east of England dealership tour soon?
Levelling up and all that??
Right on the coast, good fish and chip shop nearby!!!
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Thing is, I do not have the knowledge or expertise to make changes to the crossover. A number of folk have said that to attenuate the upper mid/treble, “it would just need a different resistor in the L pad” 
I wouldn’t know what an L pad looked like so I asked Kevin at Definitive about it. He said the xovers do not have L pads. “They’re far more sophisticated than that” he said. He also said in that call that he would contact the previous owner to see if the xover circuit diagrams were available. Not heard back from him yet.
However, the autoformers are actually a good solution. They enable adjustable attenuation (via the various taps) without any discernable loss of audio quality, and can be used by an electronics numpty like me. (that’s probably why Pete suggested them )
So to answer your question Stephen, the only permanent change will likely be to move the autoformers into the xover boxes and tidy up the wiring.
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I think John Sheerin designed the crossovers for a previous version of them, might be worth dropping him an email to see if he will give you the circuit design or any advice
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Thanks for that Chris. I’ve reached out to John Sheerin directly to see if he can help with the xover diagrams.
If all else fails it should be possible to reverse engineer them
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Just received a very long and detailed response from John Sheerin, with circuit diagrams, parts list and specific suggestions for modifying the Goto’s xovers! Good man! 
I’ve just asked him if he’s OK with it being posted on here.
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