- Posted by Jogi (A) on June 11, 2008 at 04:18:49
In Reply to: RE: parallel 6SL7 with CCS ? posted by troporobo on June 10, 2008 at 18:27:42
The changes with CCs are not subtle for me, somehow the sound has more flesh and blood, especially in complex passages there is more control and separation.
And at the same time smoother and with more attack , less distortion as it seems.Voices are sweeter and more natural and with less effort.
I compared it with a heavy car, say a nice big Benz with the engine of a VW. Then you replace it with a 8 cylinder, and compare again...
Its interesting that I prefer now CD over my very good turntable, with Mu stage it was just the opposite; maybe the driver was not able to deal with the dynamics from the CD and compressed, now its very nice.
But, as always, this is my experience, it can be different for someone else.
For the circuit:
In fact is is more simple than Mu, when you use the boards from Machmat (link below)as I did.
On his page are more facts about CCs and reports of his customers.
They are set to 2mA, B+ is 400V through changing the 62K resistor at the PS board, in my case it is 14K, but it is dependent also on your rectifier tube. And then I played a little with the catode resistor and finally settled to 230V at the anode; 1K2 / 47µF catode which results in 2,8 Volt.
Higher voltage at the anode results in brighter, more controlled sound, and less voltage it becomes softer.
I have the grid choke as well, no problems with that.
I recommend to give it a try, its simple and not expensive and its very nice.
There must be a reason Brian offers it now as upgrade instead the Mu driver...
Ah, if you are a customer of DIYsupply you can ask Brian for the circuit he uses, its almost the same except there is another transistor and no board as such is used.
Cheers,
Juergen
