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

Showing 9 responses by smatsui

I can 2nd the recommendation of the Pass Labs XA25.  I have 3 different speakers that are in rotation with this combination: (1) Devore Gibbon Super Nines, (2) Klipsch Cornwall IVs, and Sterling Broadcast LS3/6.  The XA25 drives each one with ease and sounds transparent and 3 dimensional.

@audioman58, thanks for posting about your experience with the upgrade.  My level 2 will be upgraded next week.  I ordered the upgrade over a month ago and I’ve been waiting for them to let me know when they’re ready for it.  Jacob asked me to send it in today.  I’m also getting the Ray Reserve 6SN7.  I’ve had my level 2 for about a year.  It’s great that LTA is offering the upgrade to current customers.

Does the upgrade sound good right out of the box or did it require some additional burn-in beyond what LTA does?

Two days ago you gave a rave impression of the level 3 upgrade and now you want  to sell it?  Hmm …. that gives me the impression that you’re hyping it just sell it.   Not a good look imo. I hope my impression of your post is wrong and that the upgrade is really all that you say it is.  I ordered the upgrade well before you started this thread so your impressions didn’t factor into my decision to upgrade.  I’ll find out in a few weeks how good the upgrade is for myself.

This thread has more u-turns than 500 laps at Daytona.  I’m taking the comments here with a big grain of salt.

The upgraded level 3 preamp arrived yesterday just in time for my wife’s Mother’s Day present. devilThis upgrade is a major improvement in 3 dimensionality, dynamics, bass and imaging.  The upgrade is like getting a new preamp that is better in every aspect of sound quality.  If you’re on the fence regarding this upgrade, I highly recommend just going ahead and doing it.  I couldn’t be happier the improvement in sound quality.

I’ve had my level 3 upgrade for the past 9 days and I continue to be impressed with the sound quality improvement.   The improvement in speed and detail while remaining musical isn’t subtle.  Before the upgrade, I couldn’t use the LTA preamp with my First Watt F7 because the sound was slow and somewhat soft.  By contrast, it seemed fine with my Pass Labs XA-25.  After the level 3 upgrade, the speed and detail improvements with the F7 are startling.  

I’m also very much into headphones (see my headphone system in my profile).  I think this preamp was very good with ZMF dynamic headphones (300 ohm impedance) before the upgrade.  After the upgrade, driving the ZMF Verite Open headphones, it’s even better.   I have a lot of high end headphones but the ZMF VO with the LTA level 3 preamp/headphone amp is about as good as it gets imo.  The Verite Open can be had on the used market for $1500-1700 which is still expensive but a bargain in comparison to some $4K-8K headphones.  This preamp is excellent with efficient headphones but don’t expect it to drive a power hungry Susvara or DCA Expanse well.

@sls883, same tubes in my level 3 that I had in my level 2.  I have about 200 hours on my level 3 in addition to the 1 week of burn-in at LTA.  I think it’s improved from the time I first received it.  I have not tried it with my XA-25 yet.  I’m using Sylvania 6SN7 from the late 50’s/early 60’s and Mullard 4024 (12AT7).  I like those tubes better than the stock tubes.  I also purchased the Ray Reserve 6SN7 but I haven’t tried them yet.

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.

@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.