Linear Tube Audio - Micro ZOTL - version -3 Update on upgrades


 

Having just received the Micro-Z OTL  version 2 in Feb  and seeing a much better upgrade was available . I had to do it to help complete my quest to get everything in my audio system as good as possible, and for 6 months the 30% off the upgrade stands  . Where the older model had 4 circuit boards ,now just one very high quality Ceramic board ,with  a small sister  board , Gold over thick Copper traces. To start  with an additional 80k uf  in filter capacitance over 200k in total ,more then most amplifiers,pretty much Everything is name brand parts . I have the Top of the line Lundahl input transformers  from Sweden .

having many years in Audio  and having had many audio pieces modded , this preamp is Loaded with top of the line in parts quality using worlds best Belleson low noise regulators , Nichicon GOLD capacitors ,from Japan ,AMTRAN BEST - Golden SQ  also Japan .EPCOS from Germany.Clarity-CMR -U.k  all top notch capacitors 

With balanced inputs , and the David Berning design Micro -Z-OTL output stage and Mark and engineering team . The interior is vastly upgraded, now a. Nice large toggle switch to choose  between the 6 v - 6sn7 tubes and 12v. 12sn7 , the whole tube socket area is a nice thick platform no flexing  and having just 1 Big main board not only more robust but much lower noise floor is Very apparent.   Sonically  the New version -3  is a major step up. To start I used just the stock tubes in the Version 3 to test  vs  an audio friends with the version 2 with much better Rays select 6sn7 tubes and  same Telefunken 12au7 tubes that I bought . TheNew Version is better  with ease !  Image depth is better and a deeper larger soundstage , Bass-MidBass has even better dynamics and slam, even quieter blacker back grounds, With excellent control ,and is just more tuneful, fast, and articulate.  When I decided Now it’s time to. Put in my top Rays select 6sn7 tubes And  12AU7 Telefunken Red tip medical grade  tubes . It was at minimum another  5 % Better still !! This was a substantial upgrade even with stock tubes   .I go to several audio gatherings,  the ones who have heard this all have $50k+ audio systems and stated you would have to spend well over $12k  to just to come close to this preamplifier performance music just is seamless and coherent which I totally agree !! It has the best of what tubes do best in a Big open soundstage stage , with lots of Air and separation around the instruments ,with excellent Solid state like imaging Big dynamics and ultra fast Tight Bass, much more so now in the version 3 . Listening ,to classic Beatles to Pink Floyd interactions in the micro details that before we’re barely audible now come out of the shadows and  are clear and defined , this alone to me is special .I have not found a preamp even  close in the $10k+ range that can better this SS or vacuum Tubes,  Great Job 👏 To  all at LTA Audio 👍🎶👍.

 

audioman58

One thing that I forgot to mention that for me was a significant improvement over the level 2 was the change in the grounding scheme.   I live in Michigan and I have forced air heating, and carpeted floors in my basement listening room and this results in a very dry environment that is very conducive to static.  Yes, I have a humidifier on my less than one year old high efficiency furnace.

Before the upgrade, I would get zapped whenever I initially touched the LTA preamp and other components connected to it.  The static discharge was so bad that it fried the display control board twice resulting in me having to send it back to LTA each time for a control board replacement under warranty.  In talking to Mark Schneider, he told me that the level 3 preamp outer chassis is entirely grounded.  Since getting the upgrade, I’ve noticed that I no longer get zapped at all when touching the preamp or any components connected to the preamp.

Maybe I’m the only user that experienced this problem but I know the folks at LTA have experienced this issue and perhaps that is why they changed the grounding scheme.  I also think the grounding change not only eliminated the issue I was having but also contributes in a small way to the sound quality improvement.

@smatsui I had that problem this winter.  I had a couple of pretty good sparks on a couple of occasions.  Fortunately, nothing got fried

I've gotten into the habit of touching the metal posts of my audio cabinet before I touch my LTA preamp.. 

@sls883 I’m glad to know that I’m not the only one to have the issue.  I actually did the same thing, touching the metal post of my rack before touching the preamp.   I had the issue 100% of the time only when initially touching the preamp.  If I touched the preamp a 2nd time, I would not get zapped after getting zapped the first time.  The issue was so annoying that I put a ground strap at my rack with a pin to the ground pin of an outlet.  I could feel a tingle whenever I initially touched the ground strap.  This issue has been completely eliminated with the level 3 upgrade.

@lancelock I am looking forward to your comparisons of the two preamps. The Rhumba Extreme 1.4 was my second choice, although I was never able to compare the LTA MicroZOTL Level 2 with it in my system. I went with the LTA ultimately based on price, then decided it met my needs, until the Level 3 upgrade became available.

@sls883 @smatsui I have never had a grounding/shock issue with any of my equipment, but then again my rack is solid wood.

Found this thread very informative and timely. LTA has had my preamp for the Level 3 upgrade for about three weeks. Anticipating an email anytime now that it’s being shipped.  Very excited to get it after reading this post!