Audible Illusions M3 vs M3A -- Worth the extra ?

I've used an M3 for over a year now, with phono cartridge Dyna 10X4 HO MC, and it is very impressive. It easily can handle the lower ouptput of this cartridge. Bought the AI M3 used for a bargain price. It is very impressive but for the used price you see now its spectacular. Let there be no doubt, it sounds only as good as the 4 6922 tubes inside and it eats the wrong tubes. Don't just put any NOS tubes inside because they will likely blow quickly--hours sometimes. To find the right tubes, go to someone knowledgeable and reputable as Kevin Deal at Upscale Audio.

I've owned late model M3, early M3a and late model M3a. The M3a's are definitely cut from the same sonic cloth - which I feel is extremely good, detailed and natural - but in a direct comparison, the M3a has better bass control, more liquid, more extended high's and overall a bit more neutral. M3 is a little more classic tubey. I like all of these but prefer the M3a over the M3, even given the price difference. Be careful though of the volume control: units with the stepped volume may or may not work well in your system, in that the steps are sonicly very large. I found that with the stepped unit I was not able to fine tune the volume adequately.

Regarding the comparison with the CJ PF-R, it is interesting that it seems to be worth more on the used market that the M3. It seems to me that the going price on the used market is often an indication of relative sound quality.
I'd be interested in other's comments on this point.

Billimbriale....It has been my observation over the years that the used market price is more relative to supply and demand than sonics. Demand is not always based on sound quality, but rather what is currently popular. Of course there are many factors that lead to popularity and as you well know what is popular to today may be out of vogue tomorrow regardless of how good it may actually be. This is a fickle hobbie to say the least. One of the reasons I believe you can get such low prices on the Audible Illusions is due to the fact that there are so many of them out there. This is one very successful preamp design. If the supply exceeds the demand the prices go down. Most people do not have a lot of patience when it comes to selling and will often take less just to move something fast so they can move on to what's currently popular. CJ is best known for its tube designs, not so much for solid state. There are far fewer PFRs out there on the used market and that combined with CJs reputation probably has more to due with the used price than the sonics. That said, these are both really good products, but as I stated earlier there is a very good reason why Audible Illusions has sold so many preamps over the years and why they have always had such great reviews. It's because they have been, and continue to be, one of the best designs out there regardless of price.

I have enjoyed the 3A with Gold stage for the last 4 years using both SS and tube amps to drive Logans (CLS/Aerius), Celestion (Model 300 Black) and most recently 10Ts. The Ruby and lately the Koetsu cartridges bring out a wider and deeper soundstage and excellent warmth with strings.

My only hesistation is the outboard power supply "hum". I have resolved it by turning it upside down.

For service, I recommend the Analog Room in San Jose, CA.