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

@sfpeloton glad you're liking the upgrade. I haven't talked myself into upgrading my level 2 preamp. Another hobby has been using up my money.

 

I've tried a number of 12AT7 tubes. My favorite is the Telefunken ECC801S and my second favorite is the Siemans ECC801S. I tried a number of others and some were horrible.  

 

I've also tried several NOS 12SN7 and 6SN7 tubes. Sylvania, Raytheon, GE, RCA.  I think I'm using Sylvania 6SN7WGT Gold Brand, but I couldn't swear to it.  I can't remember. 

@larsman Very funny! Yes, one of my speakers was making hideous pops. I was actually worried it might have done damage at first, but everything still sounds okay. Quite disappointed in that experience. Good to know that you landed on the right combination of tubes for your system. 
 

@sls883 Yep. The ECC801S are what I liked as well. Maybe I will eventually try some more 6SN7’s, but I don’t feel I am missing much at that moment. And my condolences that you have another expensive hobby. I can relate :)

I am using Telefunken ECC81s and went with Ken Rad VT-231s. The combination is working well in my Level 3.

I received my level 3 upgraded preamp with Ray tube 6sn7 Reserve and 12AT7 Select and have been listening to it non stop for few days now. I agree with findings that other users commented here as well as from professional reviews. To me though, the biggest change is that L3 sounds clearer than L2 by wide margin. Vocals are well separated from instruments and delicate passages or decay can be heard easily. This pre packs with musical energy in that I mean compared to L2, the upgrade has brought more enjoyment listening to rock or electric guitar materials; L3 has a great dynamic control (clear delineation between loud and softness when all happen at the same time) such that music sounds more 3D. Overall, I am pretty happy with the upgrade. At this point, I really wonder how much my system can get better at this point (but I am sure it can 😅). This experience reminded me that Preamp is the heart of any HIFI setup. I highly recommend. 

 

I upgraded my LTA preamp to level 2 about a year ago. I have been following this thread with curiosity to gauge general reactions to the level 3 upgrade. Based on all the positive responses, I will plan on upgrading over the next couple of months. I’m using the LTA preamp with the Qualiton P200 tube amp with KT150 tubes and it’s really a wonderful combination with my QLN Prestige 3 speakers. 

The reviews on the Rays Reserves seem mixed, so I’ll probably stick with the NOS tubes originally included with the unit. 

Looking forward to reporting back my own impressions on the upgrade in the near future.