Hi Guys,
First off, thanks Tyson for your remarks. I have to give you props for being so objective and fair to us in the past, which I can't say for everybody here.
There are a few issues in this thread which I like to address:
1. I agree with your assessment of your dual mono. For one, when you sold it to James and we've had it back on the bench, we found that the bias was 2 mV off. With a higher than 120 V voltage(which you probably had), this can indeed make for some anomalies in the sound. Call it grain or whatever, (also "warmer than normal") it will be there. The biasing is not so much an issue with Mosfet based amps, but it's very important in bipolar designs, especially with the immediate impact on the offset of the amps. In addition, the unit had the older transformers and internal wiring, which also makes a difference. This is part of what you hear at Mike's.
2. Mike's improvements in the parts bin are actually part of the "full Gary" mod. Coupled with all the Sonicraft's etc. the black gates make a very nice improvement indeed. I've tried them on the regular amps, and while I thought it's better, the improvements didn't justify the cost to me. After all, it has to make sense for the price / performance issue and the overall value of the amps.
3. Break - in. Again and again and again. Just as Mike said before, after over 6 months, the amps still improve. I wouldn't go that far, and have to put a more reasonable timing down, but yes, the longer the better. Where does the unit stop improving ??? Beats me. Lot of it is not so much the oh so often discussed "getting used to the sound" of the amp, but probably more the fact that the body's involvement in music changes from day to day, that the Ac quality is better at some days / times than others, etc. Nevertheless, you all know that I get ridiculed by the same people over and over again in regards to the long break in time. Just because these people have never experienced it and / or have other issues doesn't mean that it doesn't exist. There's no rational explanation, and I can't offer one either for this phenomenon. All I know is that nearly everyone of my customers experiences the same, and that I've had this experience over and over again in 15 years of dealing with SL amps. All you have to do is listen to a new amp, a 2 weeks old and a 2 month old amp side by side, (which I did !!!) and hear the difference. As for any jerks out there that want to argue that no 2 amps are identical, well, ask Mike. He measured a few of ours and can tell you about the ultra tight tolerances in the spec division of the amps.
Andrebiasing the amp / checking the bias after a few months of operation can really help. Not always, but sometimes.
4. Anybody interested in any additional individual upgrades, of course I'll do that for you guys. AND I do that for the usual $ 20. / hour rate plus parts and shipping. However, like I said before, I'm somewhat on the fence on this one.
5. As for anyone doing this by themselves: no, it doesn't void the warranty, but I can NOT be responsible for any damage or bodily harm, of course.
6. Other than that, I also have to say that the Stratos / Vandersteen match is a great one, and that should be considered as well. (but so is the Stratos / VMPS combo). Have I ever mentioned synergy????
Late,
Klaus
