MkIII  X-Over Sound
Initial Hook up
Sugden A21a amp (Neutral sounding class A SS) and matching CD21 player, Project RPM9 with Goldring 1042 and Graham Slee MM Phono stage, Used in unmodified original Cheviot cabinet. My comments on sound are based on using my equipment in my smallish size room and with my choice of x-over parts - YRMV.
1st Track - Poor very thin sound! Have I connected things properly?
By 3rd track - That’s more like it, starting to come through.
By 3rd CD - Bass is deeper and has more slam than original x-over.
By 8th CD - Improvements have slowed now but detail is finer than before. Notes and voices have layers and texture not obvious before.
Piano and Sax have a more convincing Bottom/Top than before, but on both of these instruments there is something not quite right about the middle. Timing is confusing and notes seem to merge.

Folks on the forums recommend 200/400 hrs burn in for the Sonicaps
. I’m not sure how much I believe in long run in periods for caps, but if I didn’t do it, it would always be at the back of my mind when listening criticaly.


By  90hrs - Things starting to sound much better, big difference in the last 24hrs. Bass on Level 42's World Machine brought a smile to my face,
things starting to gel. Bowies voice on Space Oddity is sounding more as I would expect, (Big Bowie fan), cymbals on that track much better than standard x-over. Overall sound now quite acceptable and better than original, midrange timing shows only slight improvement.

By 180hrs - Things sounding good, showing up the deficiencys in my vinyl system though. Never thought I would say it, but the modern CD's I have been using during the burn in sound pretty good. I initialy questioned the changes Hans Hilberink recommended on the Tannoy user group, but as things are settling I can now appreciate the voicing he has aimed for. It's very much aimed at acoustic music and for artists like Tracey Chapman or Miles Davis (Kind of Blue) I was floored by the sound with an almost holographic sound stage. Put some Led Zepp II or Black Sabbath on and it was a different story. Robert Plant and Ozzy's voices were so polite and tamed, guitars had no edge. I removed the 2ohm resistor in the LF section and things sounded completely different Plant and Ozzy now had presence and electric guitars played with some emotion. Trouble is It lost some of the magic in the mids.

By 300hrs - Very little change after 180hrs, I think 95% of the changes had taken place by then, after that any changes are very very subtle.
Overall impression is that the 2ohm resistor has to be left out, sorry Hans but in my set up I find it smears the notes. Piano has terrible timing with percussive passages just merging together, you lose the tune and tempo. I tried 2, 1, and 0.5 ohm. Any resistor here causes problems with timing.

Well I think a different approach may be needed so on to a MKIV version...............