Well there are a couple of projects I've been working on this week. I've been fairly interested in the au999 every since I read about a few over at ak who prefer it over the au9500. So one came available at a decent price so I decided to scoop it up to see for myself. It would also be a good opportunity to hone in on my restore skills.
Well be blunt and short, imo, it does not(at least in stock form). It does have a more neutral tonal balance which is surprising since the 9500 is the new replacement. It also have just a bit more clarity and a tad bit more engaging. But that's where the advantages end. The 9500(at least from memory) is much more refined, smoother, more detailed, more 3d, and have more transparency. So at this point I was wondering if it was even worth doing a restore. But I began to investigate this marvelously built amp further. Well there's a person who discovered the preamp have some issues. It was severely holding the amp part back. He noticed that it clipped way to early, and the 999 would barely even make rated power of 50wpc, which is outside the norm of most of amps/receivers of this era being under rated. So he came up with a mod known as the kevzep mod that not only removed the bottleneck of clipping way too early, but also allowed the preamp to accept up to a 10v signal(not that anyone would ever need it).
So the end result was much more headroom, a larger, more defined soundstage, more bass impact, and he was now able to get a clean 72wpc before any clipping. Well after doing the mod, I have to agree. It's a much better sounding amp after the preamp mod. The mod also lowed the noise floor a bit. My w3000 have a pretty black background now. So while still no au9500, it's not embarrassed by it anymore either. So I decided to go ahead and restore it which i completed earlier today.
Well, this thing is now good enough that if it was my only amp, I would be happy. It's much more refined, airy, smooth, and now have mids to die for. As of right now, it beats an au9500(stock) pretty easily. I wouldn't hesitate putting it up against an sx1280. It's doesn't quiet beat an sx1250, but it's close. And of couse, it still can't quiet match my fave(g9000). But given these go for 300-400.00 on ebay I can easily recommend it providing someone has the skills to at least do the preamp mod. And even at the current prices I would say it's work it to have it fully restored. Before doing anything, it could get my he6 to play at moderate levels at around 2:00 on the knob. It would clip at 2:30.
Now I can get them to moderately loud levels at 2:30 and it doesn't clip until around 3:30 on the knob. But the bass is a little thin sounding. So it's not the best pairing. The w3000 on the other hand sounds stellar! My w3000 has thunderous amounts of bass(not a phrase you will hear a lot when it comes to the w3000). They sound sooo buttery smooth and effortless with a nice deep out of your head soundstage. But unfortunately, this amp doesn't beat out neither the 500c nor my mac(that's just too much to ask) so it won't be a keeper. But it was a fun project, and I'm glad I got to experience what this amp is capable of.
On a side note, I just couldn't resist pulling the trigger on a parts/ repair au9500 that I"m also working on. I'm waiting on some signal resistors to arrive. There's only one working channel right now. But it should be an interesting comparison once I get it completely restored. Pics to follow soon.