Need advice on Unico 12AU7 tube rolling


Dear all,

I am using a Unico CD Player which uses 2 X 12AU7 (ECC82/5814) tubes. Somehow the stock tubes seem to be quite dull and lifeless. I wanted to try changing the tubes. I prefer to have more detailed sound with more clarity. Can anyone please advise on :

- What type of tubes can I try to get more lively and detailed sound ?

- Also, how can I change the tubes in Unico CD player (any procedure to follow ?). I am totally new to tubes.

- Can I get some links to where I can find some beginner info/guidance on tube rolling ?

I will highly appreciate any experiences with tube rolling with any Unico Amp/Pre or CD since most of the Unico products are using the same ECC82 tubes.

Kindly advise.

Thanks in advance.
wilfredt
When I owned a Unico the tubes I liked the best were Telefunken. Radiotechnique might work for you. The addition of Herbie's HAL-O tube dampers made them more refined and focused and is recommended.

Check out this Search link on AudioAsylum.com for posts regarding the Unico and tubes: http://db.audioasylum.com/cgi/search.mpl?forum=tubes&searchtext=unico

Good luck.
Sorry, but I overlooked an important detail of your question. I thought you were referring to the Unico integrated amp, not the CD player of which I unfortunately have no experience. The information I posted may or may not apply to the CD player. In an Audio Note CD2 CD player my favorite tube is the Amperex 7316 although both the Telefunkens and Radiotechniques are also good choices. Perhaps a Unico CD player owner will weigh in with a more informed recommendation.
I like the sound of Brimar 13D5 tubes in my Unico. They are a 12AU7 type tube and are NOS, which stands for New Old Stock. You can find them on ebay, but a more reliable source might be Tubemonger.
As noted by another poster, "NOS" stands for "New Old Stock." These are tubes manufactured years ago by well regarded companies, many who are no longer in the tube business. Some people regard these old tubes as superior. In fact, there is a dirty little secret in that some dishonest people are actually relabeling modern tubes with old labels such as GE, Mullard, Telefunken and so on. Buy NOS tubes only from a reliable source.

(Tubes have zero deterioration in storage as long as they are not physically damaged. A 50 year old tube that has never been used is as good as the day it was made.)

Many well known manufacturers of tube got out of the business years ago and almost all modern tubes are now made in Russia, China, Slovakia and the Czech Republic. There are a very few American made tubes but they tend to be specialty, broadcast or military items.
I also own this cd player. If you want detail and clarity I highly recommend Radiotechnique and RFT tubes. In terms of transparency and detail I haven't found a better tube than the Radiotechnique in my system. It may sound a little lean in your system though depending on your other components. If you want a little more body to the sound with most of the transparency of the RT & RFT then try a pair of Amperex Bugle Boys. Have fun, this player is very responsive to tube rolling.