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Best 845 tube out there?

I am running a pair of Cary CAD-211AE monoblocks with the standard no-name Chinese tubes shipped by Cary. Whilst I am happy with the sound, I think I should buy a pair of 845's to keep as backup in case something happens to these tubes.

Because I will need to buy FOUR of them, this rules out any tube that sells for stupid money (e.g. vintage RCA 845 tubes).

The only current production 845's I am aware of are:

- Shuguang 845 "standard"
- Shuguang 845B
- Shuguang 845C
- Shuguang PSVANE 845
- KR Audio 845

I have found reviews of the Shuguang 845B and 845C, but there is virtually no information out there on the new Shuguang "psvane" 845. Has anybody heard this valve, and is it a noticable improvement over the 845B and C? Also, what do people think of the KR?
amfibius
brf
1,715 posts
 
The PSVANE 845T is suppose to be a premium tube at 4 to 5 times the price of the standard 845, therefore, how do tubes with misaligned internal elements pass Quality Control? Why would a manufacture allow these tubes into the retail channel when they are trying to establish a premium brand? Why would a distributor allow this?

I was considering a pair of PSVANE 845T, but I have lost faith in the quality control and will adopt a wait and see attitude.
goldeneraguy
442 posts
 
Hifi223 , Are you sure the new TJ Full Music 845 are speced to match the Shuguang 845.I couldn't find any info on this.
In the past the TJ Full Music was close to the KR 845 tubes which couldn't be used in many amps.
Looking forward to your thoughts on the TJ tubes.
From which seller did you purchase them
brf
1,715 posts
 
Te standard FullMusic 845 (not the carbon plate) have similar specs to the Amperex/RCA 845 standard.

TJ FullMusic 845 Specs

Plate voltage 1000 1000 1250 V
Grid voltage -145 -155 -209 V
Load resistance 6 9 16 kohms
Plate current 90 65 52 mA
Signal voltage(pk) 110 145 V
Plate resistance 1.7 1.9 2.1 kohms
Output powe 24 21 24 W
goldeneraguy
442 posts
 
Brf, Thank you for the info.Do you know the filiment current for the TJ standard and the carbon plate 845 ??
brf
1,715 posts
 
TJ Full Music Carbon Plate 845 MKII is rated with 'nominal filament current - 0.6A at 10V' while the original RCA 845 tube was rated "filament current - 3.25A at 10V'. According to TJ Full Music's tube designer, for 845 tubes made with carbonized Thoriated Tungsten such as the RCA NOS 845 tube, filament current of 3.25A is required to generate sufficient electron emission for the tube to work properly. However, TJ Full Music's 845 MKII uses oxide coated filament which doesn't request as high as 3.25A filament current to generate sufficient electron emission.

TJ Full Music now makes a carbon plate 845 Mk3 (just released) that conforms to the Amperex/RCA standard. I have not heard this version.
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