[bob82274]

Ok Wayne we have all heard the rumbilings of the MENSA DIO now.  We are curious though in how is it different from the smART DIO? Are we talking basic upgrading of parts, extra mods in addition to the smART or is it in a totally different direction?

[Wayne1]

I have been playing with different things with my DI/O to see if I can take it beyond smART status.

The first thing I did was to try the riken-Ohm resistors. I liked what they did to the sound, but I really did not like the price.

After quite a long time of listening, I reluctantly decided they were worth to money, after all.

I have also changed out ALL the capacitors in the analog filters. I replaced the cable connecting the main board with the I/O board with NITRO wire. I also figured out a method to add more capacitance to the op-amp power supplies. This last step has really unleashed the beast.

While the smART DI/O has been noted to have very good dynamics and deep bass, the MENSA update improves upon this.

The riken-Ohm resistors are quite a bit smoother than the Holco/Dale-Vishay combo I have been using.

All in all it is an evolutionary change rather than a completly different direction.

Jay has the first one in the field. I will wait for his feedback before I set any prices or even determine if the MENSA package will be offered :twisted:

Other things I have played with is Cryo treatment of the entire DI/O and Power Supply. Marbles had this done to his, but he hasn't been able to tell me if there was much of a difference

[Jay S]

I will be able to listen to the Mensa after I return home from vacation on Jan 5 (package is at my office).  My MENSA has not been cryo treated but I am looking forward to the improved smoothness from the swap to Riken Ohm resistors.  The extra detail and quietness, improved bass and dynamics that are expected to result as part of the MENSA upgrade will be nice and appreciated but they aren't my priority as my ear is sensitive to smoothness.  Down the road, I'll probably ask Wayne to cryo the MENSA but only after I've fully broken it in and enjoyed it for a couple of months.

[Guan]

I have listened to Jay's smART in my system and it is indeed a feisty beastie. Very dynamic with deep bass and good transparency. I look forward to hearing the new MENSA with relish.
 
A comparo between the MENSA and my new 6021W pencil tube dac w/ DACT, choke regulation and paper-in-oil caps should prove interesting!  

[Jay S]

I got the MENSA and bybee'd power supply today.  Below are some very initial impressions -- I have only had it playing for about 3 hours, but it is clearly quite a bit different from my Cary.  Note that the Cary is plugged direct to the wall; the MENSA's bybee'd power supply is plugged into a cheapo extension strip -- it would be cool to see what clean power (such as through Guan's DeZoral, which he is now breaking in) would do.  

My girlfriend and I both noticed quite easily that the MENSA is more transparent and more detailed than the Cary.  Lyrics (e.g. Pink) are much more intelligible.  The overall sound is cleaner, which allows me to play music even louder without it really sounding loud.  I am hearing more microdynamics (e.g. when listening to the Corrs, I now hear the small changes in the way the bow interacts with the strings of the fiddle).  Bass is deeper and tighter and quicker; the differences in pitch are more distinct and musical; impact is more percussive.  The sound is also much more dynamic.  At first I heard a bit of emphasis in the mid-treble but it seems to be going away rather quickly.  The midrange seems smoother than before I had the smART upgraded to MENSA (this is based on memory, but this was the area where I had previously clearly preferred the Cary to the smART).

I have to let the MENSA fully break in and listen more to get a good sense of the sound, but the initial results are encouraging as overall the MENSA seems to be more fun to listen to than the Cary.  Some songs sound very very nice, but not as relaxed as I would expect from a fully warmed up and broken in unit.  Based on my experience with the smART, the mods need about 250-300 hours to fully burn in.  

By the way, I also received the following Bolder interconnects: a Type 2B (bybee) with bullet plugs, NITRO, M-80 and a prototype of the Dyna.  I have not had a chance at all to hook them up.  I think that the Type 2B will take my system forward; right now both of the ICs in my system are regular Type 2's with Cardas RCA plugs and no bybees.  

Finally, I received a few HALO-9s for the small tubes of my Joule preamp (and also the 300B tube integrated in my bedroom system) and 4 Tenderfoot isolation footers that I'll try on the Cary.  

Lots of stuff to try!  Unfortunately, I will be out of town from a couple of days.  I will leave the MENSA in the system so my girlfriend can use it and help me accumulate hours.

[Wayne1]

Hello Jay,

I am glad you arrived safely back to HK form your holiday. I am also glad you were able to pick up the products I shipped you.

I ran the Mensa for about 4-5 days straight before I shipped it to you.

I was not able to use the power supply at all. I still don't have 240 VAC here

The Bybee in the PS will take a bit more time to break-in. You should notice a bit of a quieter background and the microdynamics will improve even more.

Let us all know what you think of the M-80s and the NITROs vs the Type 2s.

[Jay S]

Wayne,

Thanks for the info on the break-in time.  Looks like the MENSA needs about 150 hours more, and the power supply needs the full 250 hours (assuming the bybee takes as long to break in as a new smART).  I have to say that even within my first 3 hours of listening I heard a nice improvement in the sound -- I played the same tracks at the end of the session as I did at the beginning.  

If I didn't say it before, there is a lot of detail that is now emerging from the quiet background.  I get more of a sense that there are real people playing instruments -- you can hear tiny variations in timing, small nuances that make it seem human as opposed to manufactured.  When we were listening to Norah Jones, my girlfriend commented that it was like she was standing a few feet in front of us.  

I'm looking forward to getting some serious break-in time on the MENSA and power supply.  But, things are looking very promising.  

Anybody have an idea of which universal player (Pio 47Ai?, Yamaha SD2300?) will be as good a transport (for redbook) as my Cary 303/100?

[Jay S]

Here's a quick update.... I've been using the MENSA for 2 weeks now.  During that time it has been powered up continuously, and played close to 100 hours of music.  

I have noticed improved ease and liquidity.  The sound was slightly forward when I first got it but now the front of stage starts at the speakers, same as the Cary.  The mid-treble emphasis is gone.  I'd say that the tonal balance is very even from mid-bass all the way through the treble region.  On some tracks the low bass can be a bit strong but it could smooth out with further burn in (especially since the power supply and its power cord have less than 100 hours of playing on them).  This something that I will watch.  The highest treble on my system can be a little deemphasized but I am using Type 2 interconnects and other comparisons (such as vs the NITRO) have pointed out that the top-end of these cables could be more extended.  I have other interconnects to try (NITRO, M-80, Type 2B) and will see what happens.  

I have also noticed that the power supply further benefits from being plugged into a good power filter.  Not too surprising - often power improvements are somewhat additive.  You can see my comments on the long thread on the DeZoral filter (I tried my MENSA last night with an entry level DeZoral, the LF-P1 that was kindly lent to me by Guan).  

I am enjoying the MENSA and look forward to the time when it is fully broken in.