Difference between Siemens CCa & 7308

I'd opine that in most systems a good 6922 or 7308 will suffice. To fully appreciate the nuances of Cca, the other system components must be a very high level.

I use a pair of Cca in what many users would call a reference phono stage. Yes, and as Grant says, the presentation is more refined and the imaging is better but there is a price to pay for this.

I think most users would be totally satisfied with a high quality Amperex 6922 or Siemens 7308.

YMMV

Not all Cca are created equal.

There are both great and poor examples available. Not to mention the counterfeits.

IMO, the probability of finding a great 7308 is better than finding a great Cca.

>>Audiofeil, how do you spot a great quality CCa by virture of its sound?<<

That's like asking what spinach tastes like.

To my ears the great Cca are very airy, detailed, and impart a "dimensional" aspect to the presentation. You have to listen for yourself and decide; therein lies the rub. You could put 10 experienced listeners with a series of 6922/7308/Cca tubes and more than likely there would not be clear "winner"

That being said, unless your system is up to the task, it makes little sense to spend money on Cca. I would seek out some lesser priced tubes from the same family; they will give you 98% of a top Cca at a much lower cost. I love the mid 60's Amperex Bugle Boy 6922 for example. Andy at Vintage Tube Service sells high quality products at fair prices.

Know your tube vendor. There is a plethora of counterfeit and junk tubes on the market.

>>11-05-07: Anacrusis
A food critic can tell me what spinach tastes like. Sound has much more definable characteristics. Airy, detailed, dimensional says it nicely.<<

Those are nice words. Unfortunately, there are no universal and accepted meanings for them. I suspect most listeners have their own personal definition of them based on the equipment they've heard.

I hope that helps and BTW, eat your spinach.