Tube advice

[nubbins]

I have a Yaqin Integrated Valve amp that uses a pair of EL34's for each channel and what looks like a 6N8P and 12AX7 combo in the pre-amp stage.



Currently I have some Chinese tubes in there apart from the EL34's which are Ei Yugo's.


I am looking to improve the sound of the amp and as such have just won a pair of Mullard ECC83/12AX7 (GB) valves but want to replace the rest.


I've heard that the 6N8P can be replaced with a 6SN7. For that I was looking at a pair of Electro-Harmonix gold pin valves.


For the EL34 power stage it's a toss up between the JJ Tesla's E34L or the Electro-Harmonix 6CA7 (Fat bottle EL34).



Considering the amp is integrated and will be using the Mullard ECC83's, what advice can you give me on which tubes to use/avoid.



Thanks for any help.



P.S The codes on the Mullard ECC83's are L63BOD3 and L61B2J4...good/bad?

[G]

Originally posted by nubbins
I have a Yaqin Integrated Valve amp that uses a pair of EL34's for each channel and what looks like a 6N8P and 12AX7 combo in the pre-amp stage.



Currently I have some Chinese tubes in there apart from the EL34's which are Ei Yugo's.


I am looking to improve the sound of the amp and as such have just won a pair of Mullard ECC83/12AX7 (GB) valves but want to replace the rest.


I've heard that the 6N8P can be replaced with a 6SN7. For that I was looking at a pair of Electro-Harmonix gold pin valves.


For the EL34 power stage it's a toss up between the JJ Tesla's E34L or the Electro-Harmonix 6CA7 (Fat bottle EL34).



Considering the amp is integrated and will be using the Mullard ECC83's, what advice can you give me on which tubes to use/avoid.



Thanks for any help.



P.S The codes on the Mullard ECC83's are L63BOD3 and L61B2J4...good/bad?

I would try the SED EL34s before I tried anything else. I use the EH 6CA7s with my SS preamp but I had some friends come over the other night with a Foreplay preamp and the SEDs sounded very nice in my SE EL34 amp. The EH 6CA7s are more laid back which is what you need with a SS preamp but with a tube gain stage I would try the SEDs. Make sure to get SEDs and not the new Svetlana tubes as the new Svetlana tubes are Sovteks. Svetlana is now called SED. Hope that helps.

[nubbins]

Are those SED's you mention the ones made in St. Petersburg, Russia with a brown base?

[anatech]

I'm now using 6CA7 Electroharmonix in my Eico HF-87a. Best I've heard yet. Replaced the other tubes (6SN7 & 12AX7A) and the sound just kept getting better. I've played with just about everything from the USA and Europe. Selected Philips too. There's nothing wrong with giving Electroharmonix a try at normal prices. Depends on the amp maybe.
-Chris