Tube choice for yaqin cd3 buffer

[acer89]

Novice here from the UK

I need 2x tubes for my new Yaqin cd3 tube buffer. These are to replace the Chinese stock tubes

According to the Yaqin website:

,Tube Buffer,SD-CD3 - Tube Buffer
SD-CD3 - Tube Buffer

Specifications:

●Vacuum Tube:6N8P × 2

It has 6SN7 / 6H8C / 6N8P written on the plate were the tube sits. What are the best and long lasting ?

I particularly enjoy a warm sound. I'm thinking RCA "red base" but you may recommend better.

I'm a novice so need to know if 5691 and 5692 have the same pin fitting and will the 5691 work in the buffer?

Thank you

 

[tubeman813]

Hi acer 89,

The 5691 is equal to the 6SL7GT, same pin layout.

The 5692 is equal to the 6SN7GT, also same pin layout.

But you need the 6SN7 GT for your use in you CD tube buffer.

So, the 5692 can fit, too.

Also the 6H8C / 6N8P is equal to 6SN7 GT.

I found out, if you replace the 6SN7 GT with 6N8P, I had more hum issue.

 

[acer89]

Thank you for the reply... So assume the RCA 5691's are a no go but the 5692 are OK?

If I'm correct I'll face hum problems if I use 5691's but not if I use 5692's?

Damn ...these RCA red cap tubes are pricey!

I like a warm but full bodied sound. I listen a lot on Grado RS1 headphones so I don't want anything which will cause listening fatigue.

Any other tube you can recommend?

I'd also like to upgrade the caps but again not sure which to choose to achieve the sound I like.

 

[kevinkr]

I am a fan of the Sylvania 6SN7GTB and prefer it to any 5692 I have yet encountered. My favorite 6SN7. YMMV of course.

WWII vintage RCA grey or black glass 6SN7GT are also quite nice, but are advisable only if the plate voltage is not much over 300V. You will find these pretty pricey.

The Brimar 6SN7 is also quite good if a bit rare these days.

 

[acer89]

Thanks for the reply. As mentioned I'm a novice and have no idea what you mean by "My favorite 6SN7. YMMV of course."

Please explain

 

[tubeman813]

Hi acer89,

Yes, you have to use the 6SN7 GT type, tube for your tube buffer.

I write to you, that the Russian style 6H8C or 6N8P tubes can make hum problems.

There are many many different 6SN7 GT tubes out there.

Take a look her for example: 6SN7GT, Tube 6SN7GT; Röhre 6SN7GT ID5084, Double Triode

If you like warm sound, you should buy different type of 6SN7 GT and listen to them.

 

[tazzo]

Hi acer, I've seen your post in another audio forum, and just to echo what I wrote there;


I bought this, upgraded it last year with Mundorf evo in oil capacitors and Shuguang CV181-Z 50th anniversary treasure tubes - premium grade. One reviewer said they beat his Sylvanias. Probably the best out there for the type of tube you are looking for and will set you back around £125. Psvane, however the group that designed tubes for Shuguang have started making their own tubes, and the update to the treasure tube is looked upon as the Psvane CV181-Z TII. Below is a link to a very reputable supplier.

Psvane & Shuguang Treasure Audio Tubes, Caps and Amps | Manufacturer Authorized Worldwide 5A Standard Re-seller

Useful link;

http://www.diyaudio.com/forums/tubes-valves/183529-yaqin-sd-cd3-tube-buffer-upgrading-caps.html

Its a small world mate.