1. CV181-Z Select (pair, equivalent to 6SN7)


We are adding back in the Shuguang Treasure CV181-Z black bottle tubes in Nov 2013 to meet customers’ demands for ‘black bottle’ tubes (vs. Psvane Audio’s grey bottle Psvane CV181-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 CV181-Z tubes sold by Chinese vendors online (those are without our unique quality control process), all our CV181-Z tubes have ‘Select’ printed on the glass to identify its source.

The ‘Select’ grade CV181-Z will be packed in plain kraft carton box with 2 tubes as a matched pair. No Shuguang black gift box included to further identify these tubes with those offered by Chinese vendors with unknown quality.


This tube is a true 6SN7 equivalent and you can use it in place of 6SN7 tubes of various brands. It has identical specification as RCA 6SN7. Do not use it to replace NOS CV181 tube.

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 6SN7 family of tubes
  • Suggested burn-in time 150-300 hours. Most changes happen in the first 150 hours.
  • Note: this tube is taller and fatter than most other 6SN7. The widest part is 2″ diameter, and it is 4″ tall from base (not including the pins) up. Please check your amp to see if the tube will fit before you purchase. The tube base is made of ceramic which is 3.5cm (about 1 3/8″) in diameter slightly larger than an average 6SN7 tube base. 

Download Treasure CV181-Z Spec sheet

Compare spec to RCA 6SN7

” It succeeds in beating the best NOS samples at their own games with the added bonus of new stock reliability and dependability”…. “I have spent many long hours burning-in and auditioning NOS 6SN7 (there’s so many to choose from) and the Shuguang CV181Z beats them all with maybe 50 hours on them and they claim to need 300 hours”

Mark Wheeler – TNT-Audio, Read the full review here.

Please select:

Price: $199.00

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