ZOTL40 Reference+ Upgrade Program

Two years after releasing the award-winning ZOTL40 Reference power amp, LTA is proud to announce the next generation of our flagship amp, the ZOTL40 Reference+.

After trying over two dozen component combinations, and countless hours of listening tests and comparisons, the new ZOTL40 Reference+ upgrade improves the tone and texture across all frequencies, and there is more detail and clarity around the performers.

These sonic upgrades are achieved through adding a massive 100,000µF of additional capacitor storage and changing resistors at key points in the audio path to non-magnetic Audio Note Tantalums, each value specifically chosen for their location.

Free shipping is included in all Reference+ upgrades for US customers.

Listening Notes from LTA’s Director of Sonic Quality

Yes, that is a real job title - some people have all the luck - and along with a cadre of test listeners, it’s their job to make sure the sound of the Reference+ upgrades keeps the LTA sound our customers love while raising the bar in the right areas.

Whether you are Sunday morning classical, late night jazz, or sweaty rock club listeners, everything comes out sounding sweet and immersive with the Reference+ version. There is tonal sheen, midrange elegance, and startling, controlled dynamics like never before. The Reference+ upgrades reveal more emotion in the music.

We’ve found that with the Reference+ update, listening fatigue is a footnote of the past, no matter the source. Even the most challenging torture tracks become immediately palatable and better yet, unskippable. When pushing to "live sound" decibels, instruments and vocals stay in place and simply get more vivid and real instead of breaking up or becoming shouty (suggesting the listener be more reasonable with the volume control.)

Whatever your preference, you'll find new appreciation for your all time favorites and fall in love with the latest new releases.

Upgrade your ZOTL40 MkII or ZOTL40 Reference power amp

The Reference+ Upgrade can be applied to all existing ZOTL40 Mk II and ZOTL40 Reference power amplifiers.

Note to ZOTL40 MkII owners: The Reference+ Upgrade does not include the Mullard EL34 tube upgrade or the upgrade to the Fern & Roby Case. You can purchase each of these separately at the Amp Upgrades page.

How It Works

1. Place your upgrade order

2. LTA will send you a return shipping label

3. Pack your amp securely in its original box and packaging (if you don’t have the original packaging, let us know), affix the label, and take it to your closest UPS Store

4. When we receive your amp, we’ll do the upgrades and ship it back to you ASAP after a couple days of play-testing and burn-in. We will have your amp for about a week, give or take, once it’s received.

5. Enjoy!

Z40 Integrated Owners

Yes, we are working on implementing the Reference+ upgrades into the Z40 Integrated. Due to the added complexity of the integrated version, these will be released in the coming months and will be available from this page.