We are adding back in the Shuguang Treasure KT88-Z black bottle tubes in Aug 2013 to meet customers’ demands for ‘black bottle’ tubes (vs. Psvane Audio’s grey bottle Psvane KT88-TII tubes). With collaboration with Shuguang’s quality control team, we offer ‘Select’ grade tubes with extra screening, matching plus additional 50 hours of burn-in to reduce defect rates and improve on reliability. These tubes are only available from our website and we do NOT offer through any re-sellers to ensure buyers will receive genuine ‘Select’ grade high quality tubes from us.
To make sure buyers not to confuse our ‘Select’ tube offering with the mixed quality KT88-Z tubes sold by Chinese vendors online (those are without our unique quality control process), all our KT88-Z tubes have GF-Select printed on the tube to identify them.
The ‘Select’ grade KT88-Z will be packed in plain kraft carton box with 4 tubes as a matched quad. No Shuguang black gift box included to further identify these tubes with those offered by Chinese vendors with unknown quality.
True “Treasure” as a result of Shuguang’s 50-years’ of expertise in vacuum tube design and production.
High Polymer Compound Carbon (HPCC) coating is for the first time used on vacuum tube production. Compared to traditional carbon spray technology, HPCC coating will allow greater concentration of electrons, enhance and maintain stability of the electron flow, maximize “secondary electron emission surpression” from the glass enclosure, in turn reduce effects of electron swirl which generates internal noises from the vacuum tube itself.
‘Super Alloy’ technology is for the first time used in constructing vacuum tube. ‘Super Alloy’ technology was invented and first used in aviation, aerospace, military and other high-tech area. After 3 years of testing under extreme conditions, Shuguang has successfully adopt such technology in vacuum tube constructing to achieve directional solidification and single crystallization, greatly improving the ability of electron emission and electron current stability.
- Improved vacuuming technology during production process to clear signal background
- Key assembling process is manually completed by a small number of senior technicians with 30+ years of experience.
- 60 extra parts selection and matching processes are adopted to ensure premium quality tubes, compared to the Shuguang generic clear glass tubes.
- Premium Grade matched right out of factory to serve outside of China market
- Interchangable with KT88 family of tubes for output of 10w
- Suggested burn-in time 150-300 hours. Most changes happen in the first 150 hours.
Reviewer Nel Ferre says: “Beyond good… these are great!” “I found that I preferred the Treasure Series 6CA7 to the regular grade Shuguang KT-88 in my system for their extended highs and midrange beauty. I appreciated the Treasure Series’ bass texture, but I found myself wishing for more authority. That is where the Treasure KT88’s extra bass grunt came into play. I found these to be my favorite of the lot, by a big margin. I found them to be the most balanced of the tubes I have on hand top to bottom, with incredible detail. Dynamics, both micro and macro… check. The Treasure Series KT88 really has it all — just like a Black and Tan. Keep in mind, I am not slighting the Treasure Series 6CA7 — I still preferred them to my usual tubes. This is high praise”.
“Shuguang’s Treasure Series 6CA7-Z and KT-88Z tubes are both stellar performers. ….While the Treasure Series 6CA7 is the only EL34 type tube that I have ever heard that I could easily live with long term, their KT88s (to my ears and taste) are even better yet. Though I prefer the KT88s both models are very highly recommended”.
Read the full review here.