Whaleman wrote:
Thanks Lorne, what kind of new characteristic did the sound take? My CS-99As sound quite dull, so anything will be an improvement.
Three separate cases. You should keep in mind some alterations that I made to the circuits in two of them:
Tannoy IIILZ (a sealed box, bookshelf design) with a 10 inch, Monitor Gold dual concentric driver: The original sound was pleasant and even articulate, but it lacked punch and bottom end. They sounded better when driven hard, and I knew that one side was dragging its feet. The gain and energy switches did not seem to provide any solutions in their operation. So, I replaced all the original electrolytics with common 5% Marcon polyester film caps. I had to wire them in parallel to produce exact replacement values. What I took to be the "polite British sound" of apocryphal reputation vanished. They were still euphonic and pleasant, but they now had a more distinct, dynamic range. They became more useful for a greater range of musical genres. The bottom end did not extend very much, but what was there blossomed. Low level, near-field listening became a late night pleasure. There was a whole world of detail that was not there before. I deleted the gain circuits, and I wired the network for 'flat'.
Pioneer CS-655 — a very nice Japanese, domestic, 3-way speaker model using coniferous ply, sealed boxes. I used the Mitsubishi Mylar or polyester film caps and made a piggyback circuit board for them. I deleted the gain pots (I wish I had left them in). Then I substituted R's for the pots as they would have been seen in 'flat' setting. The results were not as dramatic as in the case of the Tannoys. Perhaps the original caps were not as tired. But then, unlike your CS-99a’s and my old Tannoys, there was NOTHING dull about them to start with. Nevertheless, after recapping there was a bit more detail, and a bit richer bottom end — a worthwhile effort and worth the peace of mind.
Sansui SP-G88 — Three way using carbon fibre woofs and mids with a titanium driver. Astonishing improvement. Before recapping, this speaker was very impressive at extremely loud levels — I mean realistic night club dance mix wake up the neighbours dog howling antisocial mayhem — something I rarely do, and only when “she who must be obeyed” is outta town. That being said, they were otherwise boring and OK for running the family TV/DVD complex. Then one day I decided to recap them in stages. As I progressively changed out each cap, the sound got better and better. Now they are powerful and yet delicate. Detail has blossomed. I now hear tonal textures that were not obvious before — tonal texture such as the sound of a resined bow on strings, or the character of a Spanish guitar string. The human voice has become much more intimate. The bottom end has filled out and extended. Percussion has gained in tonal character. (I hate hearing just wacks and thuds). The sound stage has improved a lot too. These speakers have transformed into convincing and realistic musical instruments. There is so much more tonal character that I am experiencing the artistic intent in the music that was not available before. Very exciting. Except for a mixture of Mylar and polypropylene substitute, replacement caps, these speakers remain absolutely stock. Obviously, there was a LOT of speaker tech in there before I started.
In each exercise, I have gained something for no sustained losses.
